| 2021 | The Consumption of Energy Drinks Induces Blood-Brain Barrier Dysfunction in Wild-Type Mice. | Front Nutr | Energy drinks containing significant quantities of caffeine and sugar are increasingly consumed, particularly by adolescents and young adults. Chronic ingestion of energy drinks may potentially regulate vascular risk factors. This study investigated the effects of chronic ingestion of energy drinks on blood-brain barrier (BBB) integrity and neuroinflammation. Male C57BL/6J mice were maintained on water (control), Mother (ED), sugar-free Mother (sfED), or Coca Cola soft drink (SD) for 13 weeks. The BBB integrity and neuroinflammation were analyzed with semi-quantitative immunofluorescent microscopy. Blood pressure, plasma inflammatory cytokine levels and blood glucose were also considered. Following 13 weeks of intervention, mice treated with ED, sfED, and SD showed significant disruption of BBB. However, marked neuroinflammation was observed only in sfED group mice. The consumption of ED and sfED significantly altered the blood pressure and plasma concentrations of inflammatory cytokines, TNF-a, IL-4, IL-6, and IL-10, and both increased plasma glucose. Correlation analyses showed significant associations between BBB dysfunction and hypotension, hyperglycaemia and cytokine dyshomeostasis. The intake of energy drink, particularly the sugar free formulation, may compromise the integrity of BBB and induce neuroinflammation via hypotension, hyperglycaemia and inflammatory pathways. |
| 2021 | [Effects of dexmedetomidine doses on postoperative cognitive dysfunction and serum β- amyloid and cytokine levels in elderly patients after spine surgery: a randomized controlled trial]. | Nan Fang Yi Ke Da Xue Xue Bao | To explore the immunomodulatory mechanism and optimal dose of dexmedetomidine (DEX) for preventing postoperative cognitive dysfunction (POCD) in elderly patients undergoing spinal surgery.A total of 120 elderly patients undergoing elective spinal surgery with general anesthesia were randomized into 4 groups to receive a loading dose of 0.3 μg/kg DEX for 10 min before anesthesia induction followed by maintenance doses of 0.2, 0.5, and 0.8 μg · kg·h (low-, medium-, and high-dose DEX groups, respectively) or an equal volume of normal saline (control group). DEX and saline was discontinued 40 min before the end of the surgery. Before induction (D) and on day 1 (D), day 3 (D) and day 7 (D) after the operation, the cognitive function of the patients was assessed using the MMSE scale and their serum levels of β-amyloid (Aβ), TNF-α, IL-1β and IL-6 were measured. The occurrence of adverse effects including bradycardia and hypotension and the recovery time of the patients were recorded.Compared with those on D, serum levels of Aβ, IL-1β, IL-6, and TNF-α on D were markedly increased in all the groups ( < 0.05); the levels of Aβ decreased to the baseline level on D in medium- and high-dose DEX groups ( > 0.05) but remained high in the other two groups. On D, TNF-α, L-1β and IL-6 recovered their baseline levels in medium- and high-dose DEX groups ( > 0.05) but remained elevated in the other two groups. The incidences of POCD in medium- and high-dose DEX groups were comparable but significantly lower than that in the control group ( < 0.05). The incidences of hypotension and bradycardia were the highest in high-dose DEX group ( < 0.01), which also had longer recovery time than the other 3 groups ( < 0.05).With a loading dose of 0.3 μg/kg followed by a maintenance doses of 0.5 μg · kg·h, DEX can effectively reduce the incidence of POCD in elderly patients undergoing spinal surgery by inhibiting the production of Aβ and pro-inflammatory cytokines. |
| 2021 | Effects of high-flux hemodialysis combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition of elderly patients on maintenance hemodialysis. | Ann Palliat Med | This study was to investigate the effect of high-flux hemodialysis (HD) combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition in elderly patients on maintenance HD (MHD).75 MHD elderly patients admitted to hospital between 1st September 2017 and 31st August 2019 were selected as the study subjects. They were randomly divided by digital table into three groups: low-flux group (n=25), high-flux group (n=25) and joint group (n=25). In the low-flux group, dialyzer had an ultrafiltration coefficient 12 mL/(h·mmHg) and effective surface area of 1.4 m2 compared with 59 mL/(h·mmHg) and 1.8 m2 in the high-flux group. After treatment, the calcification of blood vessels was examined by lateral X-ray, pelvic plain film and bilateral positive position. For patients in all groups, the concentrations of parathyroid hormone (PTH) and β 2-microglobulin (β 2-MG) in serum were measured by automatic chemiluminescence; levels of interleukin-6, C-reactive protein (CRP), and tumor necrosis factor alpha (TNF-α) were measured by ELISA before and after treatment; and the level of hepcidin was measured by ELISA. Before and 12 weeks after the treatment, the nutritional status of the patients was evaluated by modified quantitative subjective global assessment (MQSGA), hemoglobin (Hb) and red blood cell count (RBC). Complications in the three groups were recorded, including nausea, chest pain, hypotension, hypertension, pruritus, dry heat, muscle spasm, arrhythmia, and restless legs.Vascular calcification in the joint group was better than the low-flux and high-flux groups (P<0.05). After treatment, the serum PTH and β 2-mg concentrations in the joint group were lower than those in the other two groups (P<0.05), and the levels of IL-6, CRP, TNF-α and hepcidin in the joint group were significantly lower than those before treatment (P<0.05). After treatment, the MQSGA scores in the joint group were lower than those in the low-flux and high-flux groups (P<0.05), and Hb and RBC were higher (P<0.05).The combination of high-flux HD and levocarnitine in elderly patients on MHD can increase the clearance of medium and large molecular toxins, effectively correct malnutrition, alleviate microinflammation, delay the progress of vascular calcification, and is safe. |
| 2020 | Trimetazidine Increases Plasma MicroRNA-24 and MicroRNA-126 Levels and Improves Dyslipidemia, Inflammation and Hypotension in Diabetic Rats. | Iran J Pharm Res | Trimetazidine (TMZ) improves endothelial dysfunction. However, its beneficial effect on endothelial miRNAs is unexplored in diabetes. The aim of the present study was to evaluate the effects of TMZ on plasma miRNA-24 and miRNA-126, dyslipidemia, inflammation, and blood pressure in the diabetic rats. Adult male Sprague-Dawley rats were randomly assigned into four groups (250 ± 20 g, n = 8): a control (C), an untreated diabetic (D), a diabetic group administrated with TMZ at 10 mg/kg (T10), and a diabetic group administrated with TMZ at 30 mg/kg (T30) for eight weeks. Diabetes was induced by injection of alloxan (120 mg/kg). The plasma levels of miR-24, miR-126, lipid profile, malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), blood glucose, body weight and systolic blood pressure were measured. The diabetic rats showed decreased plasma miR-24, HDL-c ( < 0.05), miR-126 ( < 0.01), body weight changes percent, body weight, and systolic blood pressure ( < 0.001) and increased triglycerides (TG), VLDL-c ( < 0.05), TNF-α, total cholesterol (TC) ( < 0.01) glucose, MDA and IL-6 ( < 0.001). Interestingly, all these changes were significantly improved by TMZ treatment. Our findings propose that TMZ has protective effects on decreased plasma miR-24 and miR-126 levels, inflammation, dyslipidemia and hypotension, and it may participate in endothelial dysfunction and atherosclerosis. |
| 2021 | Pro-inflammatory cytokines as potential predictors for intradialytic hypotension. | Ren Fail | Intradialytic hypotension (IDH) is a common complication in maintaining hemodialysis (MHD) patients. Immune activation might be part of the mechanisms. However, the association between pro-inflammatory cytokines and blood pressure (BP) has not been deeply explored. So we aim to evaluate the potential role of pro-inflammatory cytokines in IDH.MHD patients starting hemodialysis before January 2016 were enrolled in our retrospective study. Patients' characteristics, laboratory results, and intradialytic BP were collected. IDH was defined as nadir systolic BP ≤ 90 mmHg during hemodialysis. The definition of IDH group was that those who suffered from more than one hypotensive event during one month after the enrollment (10% of dialysis treatments). Spearman correlation analysis and logistic regression were employed to explore the relationship between pro-inflammatory cytokines and IDH.Among 390 patients, 72 were identified with IDH (18.5%). High levels of serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were observed in the IDH group ( < 0.001). Both TNF-α and IL-1β positively correlated with predialysis BP ( < 0.01). Receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic accuracy of serum IL-1β and TNF-α for IDH. The area under the curve of IL-1β was 0.772 (95% CI: 0.708-0.836, < 0.01), and that of TNF-α was 0.701 (95% CI: 0.620-0.781, < 0.01). After adjusting for patients' characteristics, biochemical parameters, comorbid conditions, predialysis BP, and medications, elevated TNF-α and IL-1β were still risk factors for IDH.Pro-inflammatory cytokines (TNF-α and IL-1β) could be potential predictors for IDH. |
| 2021 | Expressions and related mechanisms of miR-212 and KLF4 in rats with acute kidney injury. | Mol Cell Biochem | Acute kidney injury (AKI) occurs in 30%-70% of critically ill patients. Multiple organ failure (MOF), which is most often secondary to hypotension and septicemia, is a global public health problem. The prognosis of patients is poor. Currently, there is no specific therapeutic method. Finding new therapeutic targets is significant to improve the prognosis of AKI patients. This study explores expressions and related mechanisms of miR-212 and Kruppel-like factor 4 (KLF4) in rats with AKI. Sixty Wistar rats were randomly divided into 6 groups: Control group, sham operation group, model group, miR-212-agomir group, miR-212-antagomir group, miR-212-agomir+APTO-253 (joint group), n = 10. The expressions of miR-212, KLF4, inflammatory factors [tumor necrosis factor α (TNF-α), interleukin 6 (IL-6)], oxidative stress factors [superoxide dismutase (SOD), malondialdehyde (MDA)], and apoptosis-related proteins (bax, bcl-2) in renal tissue of rats were detected, and the relationship between miR-212 and KLF4 and the severity of AKI in rats were analyzed. The expression level of miR-212 increased (P < 0.05) and the expression level of KLF4 decreased (P < 0.05) in renal tissue of rats with AKI. miR-212 was negatively correlated with KLF4 expression (P < 0.05). MiR-212 was positively correlated with expressions of TNF-α, IL-6, MDA, and bax (P < 0.05), negatively correlated with expressions of SOD and bcl-2 (P < 0.05), KLF4 was negatively correlated with expressions of TNF-α, IL-6, MDA and bax (P < 0.05), and positively correlated with expressions of SOD and bcl-2 (P < 0.05). MiR-212 mimics can inhibit the luciferase activity of Wt-KLF4 (P < 0.05), and miR-212 inhibitor can promote the luciferase activity of Wt-KLF4 (P < 0.05). Down-regulation of miR-212 plays a protective role by targeting up-regulation of KLF4 to inhibit renal tissue inflammation, oxidative stress, and apoptosis in rats with AKI, which may be a potential target for clinical treatment of AKI in the future. |
| 2020 | Angiopoietin-2 is released during anaphylactic hypotension in anesthetized and unanesthetized rats. | PLoS One | Angiopoietin (Angpt)-2, a permeability-increasing growth factor, is involved in vascular leakage of sepsis and acute lung injury, and could be released from endothelium in response to anaphylaxis-related secretagogues such as histamine and leukotrienes, or cytokines. However, roles of Angpt-2 in the hyperpermeability during systemic anaphylaxis are not known. Thus, we determined plasma levels of Angpt-2 and cytokines and vascular permeability during anaphylactic hypotension in unanesthetized rats. Anaphylaxis was induced by an intravenous injection of ovalbumin antigen. Mean arterial blood pressure (MBP) was measured, and hematocrit (Hct) and plasma levels of Angpt-2 and cytokines were assessed for 24 h after antigen injection. Separately, vascular permeability was measured in various organs using the Evans blue dye method, and Angpt-2 mRNA expression in liver was measured. After antigen injection, MBP decreased to the nadir at 6 min, and returned to baseline at 45 min, and Hct peaked at 20 min and thereafter progressively declined, suggesting that vascular leak and hypotension occurred within 20 min. Plasma Angpt-2 levels began to increase significantly at 1 h after antigen, reaching the peak 2.7-fold baseline at 6 h with a return to baseline at 24 h. Detected cytokines of IL-1α, IL-1β, IL-6, IL-10, and TNF-α peaked 1 or 2 h after antigen. Angpt-2 mRNA increased at 2 h and showed an increasing tendency at 6 h. Vascular permeability in bronchus, trachea, intestines, mesentery and skeletal muscle was increased at 10 min but not at 6 h after antigen. In addition, we confirmed using anesthetized rat anaphylaxis models that plasma Angpt-2 levels increased at 1 h after antigen. In conclusion, plasma Angpt-2 is elevated presumably due to increased cytokines and enhanced gene transcription during anaphylaxis in anesthetized and unanesthetized rats. |
| 2020 | Profound Hypotension before Aortic Clamping Can Exacerbate Spinal Cord Ischemic Injury after Aortic Surgery in Rats. | J Clin Med | Spinal cord ischemia is one of the most serious complications of aortic repair in patients with acute aortic syndrome. However, the effect of hypotension before aortic clamping on spinal cord injury has not been documented. A total of 48 male Sprague-Dawley rats were randomly divided into four groups: the sham group; control group (mean arterial pressure (MAP) < 90% of baseline value before aortic clamping); mild hypotension group (MAP < 80%); and profound hypotension group (MAP < 60%). Spinal cord ischemia was induced using a balloon-tipped catheter placed in the descending thoracic aorta. Neurological function of the hind limbs was evaluated for seven days after reperfusion and recorded using a motor deficit index (MDI). The spinal cord was then harvested for histopathological examination and evaluation of oxidative stress and inflammation. The profound hypotension group demonstrated a significantly higher MDI 48 h post-reperfusion and lower number of normal motor neurons than the other groups ( < 0.001). The levels of tissue malondialdehyde and tumor necrosis factor-α (TNF-α) were also significantly increased in the profound hypotension group compared with other groups. Profound hypotension before aortic clamping can aggravate neurologic outcomes after aortic surgery by exacerbating neurologic injury and reducing the number of normal motor neurons. |
| Coronavirus-19 (SARS-CoV-2) induces acute severe lung inflammation via IL-1 causing cytokine storm in COVID-19: a promising inhibitory strategy. | J Biol Regul Homeost Agents | SARS-Cov-2 infection causes local and systemic inflammation mediated by pro-inflammatory cytokines and COX-2 eicosanoid products with metabolic dysfunction and tissue damage that can lead to patient death. These effects are primarily induced by IL-1 cytokines, which are involved in the elevation of hepatic acute phase proteins and fever. IL-1 has a broad spectrum of biological activities and participates in both innate and acquired immunity. In infections, IL-1 induces gene expression and synthesis of several cytokines/chemokines in both macrophages and mast cells (MCs). The activation of MCs triggers the secretion of mediators stored in the granules, and the de novo synthesis of pro-inflammatory cytokines. In microorganism infections, the release of IL-1 macrophage acts on adhesion molecules and endothelial cells leading to hypotension and septic shock syndrome. IL-1 activated by SARS-CoV-2 stimulates the secretion of TNF, IL-6 and other cytokines, a pro-inflammatory complex that can lead to cytokine storm and be deleterious in both lung and systemically. In SARS-CoV-2 septic shock, severe metabolic cellular abnormalities occur which can lead to death. Here, we report that SARS-CoV-2 induces IL-1 in macrophages and MCs causing the induction of gene expression and activation of other pro-inflammatory cytokines. Since IL-1 is toxic, its production from ubiquitous MCs and macrophages activated by SARS-CoV-2 can also provokes both gastrointestinal and brain disorders. Furthermore, in these immune cells, IL-1 also elevates nitric oxide, and the release of inflammatory arachidonic acid products such as prostaglndins and thromboxane A2. All together these effects can generate cytokine storm and be the primary cause of severe inflammation with respiratory distress and death. Although, IL-1 administered in low doses may be protective; when it is produced in high doses in infectious diseases can be detrimental, therefore, IL-1 blockade has been studied in many human diseases including sepsis, resulting that blocking it is absolutely necessary. This definitely nurtures hope for a new effective therapeutic treatment. Recently, two interesting anti-IL-1 cytokines have been widely described: IL-37 and IL-1Ra. IL-37, by blocking IL-1, has been observed to have anti-inflammatory action in rodents in vivo and in transfected cells. It has been reported that IL-37 is a very powerful protein which inhibits inflammation and its inhibition can be a valid therapeutic strategy. IL-37 is a natural suppressor of inflammation that is generated through a caspase-1 that cleaves pro-IL-37 into mature IL-37 which translocates to the nucleus and inhibits the transcription of pro-inflammatory genes; while IL-1Ra inhibits inflammation by binding IL-1 to its IL-1R (receptor). We firmly believe that blocking IL-1 with an anti-inflammatory cytokine such as IL-37 and/or IL-1Ra is an effective valid therapy in a wide spectrum of inflammatory disorders including SARS-CoV-2-induced COVID-19. Here, we propose for the first time that IL-37, by blocking IL-1, may have an important role in the therapy of COVID-19. |
| IL-1 induces throboxane-A2 (TxA2) in COVID-19 causing inflammation and micro-thrombi: inhibitory effect of the IL-1 receptor antagonist (IL-1Ra). | J Biol Regul Homeost Agents | IL-1 induces a significant number of metabolic and hematological changes. In experimental animals, IL-1 treatments cause hypotension due to rapid reduction of systemic blood pressure, reduced vascular resistance, increased heart rate and leukocyte aggregations. IL-1 causes endothelial dysfunction, the triggering factor of which may be of a different nature including pathogen infection. This dysfunction, which includes macrophage intervention and increased protein permeability, can be mediated by several factors including cytokines and arachidonic acid products. These effects are caused by the induction of IL-1 in various pathologies, including those caused by pathogenic viral infections, including SARS-CoV-2 which provokes COVID-19. Activation of macrophages by coronavirus-19 leads to the release of pro-inflammatory cytokines, metalloproteinases and other proteolytic enzymes that can cause thrombi formation and severe respiratory dysfunction. Patients with COVID-19, seriously ill and hospitalized in intensive care, present systemic inflammation, intravascular coagulopathy with high risk of thrombotic complications, and venous thromboembolism, effects mostly mediated by IL-1. In these patients the lungs are the most critical target organ as it can present an increase in the degradation products of fibrin, fibrinogen and D-dimer, with organ lesions and respiratory failure. It is well known that IL-1 induces itself and another very important pro-inflammatory cytokine, TNF, which also participates in hemodynamic states, including shock syndrome in COVID-19. Both IL-1 and TNF cause pulmonary edema, thrombosis and bleeding. In addition to hypotension and resistance of systemic blood pressure, IL-1 causes leukopenia and thrombocytopenia. The formation of thrombi is the main complication of the circulatory system and functionality of the organ, and represents an important cause of morbidity and mortality. IL-1 causes platelet vascular thrombogenicity also on non-endothelial cells by stimulating the formation of thromboxane A2 which is released into the inflamed environment. IL-1 is the most important immune molecule in inducing fever, since it is involved in the metabolism of arachidonic acid which increases from vascular endothelial organs of the hypothalamus. The pathogenesis of thrombosis, vascular inflammation and angigenesis involves the mediation of the activation of the prostanoid thromboxane A2 receptor. In 1986, in an interesting article (), we reported for the first time that IL-1 induces thromboxane B2 (TxB2) releases in activated neutrophils and macrophages. An increase in thromboxane can induce leukocyte aggregation and systemic inflammation, which would account for the dramatic thrombi formation and organ dysfunction. Hence, IL-1 stimulates endothelial cell-leukocyte adhesion, and TxB2 production. All these events are supported by the large increase in neutrophils that adhere to the lung and the decrease in lymphocytes. Therefore, ecosanoids such as TxA2 (detected as TxB2) have a powerful action on vascular inflammation and platelet aggregation, mediating the formation of thrombi. The thrombogenesis that occurs in COVID-19 includes platelet and cell aggregation with clotting abnormalities, and anti-clotting inhibitor agents are used in the prevention and therapy of thrombotic diseases. Prevention of or induction of TxA2 avoids thrombi formation induced by IL-1. However, in some serious vascular events where TxA2 increases significantly, it is difficult to inhibit, therefore, it would be much better to prevent its induction and generation by blocking its inductors including IL-1. The inhibition or lack of formation of IL-1 avoids all the above pathological events which can lead to death of the patient. The treatment of innate immune cells producing IL-1 with IL-1 receptor antagonist (IL-1Ra) can avoid hemodynamic changes, septic shock and organ inflammation by carrying out a new therapeutic efficacy on COVID-19 induced by SARS-CoV-2. |
| 2020 | Pediatric Crohn Disease and Multisystem Inflammatory Syndrome in Children (MIS-C) and COVID-19 Treated With Infliximab. | J Pediatr Gastroenterol Nutr | Coronavirus disease 2019 (COVID-19) may lead to a severe inflammatory response referred to as a cytokine storm. We describe a case of severe COVID-19 infection in a recently diagnosed pediatric Crohn disease patient successfully treated with tumor necrosis factor-alpha (TNF-α) blockade. The patient presented with 5 days of fever, an erythematous maculopapular facial rash, and abdominal pain without respiratory symptoms. SARS-CoV-2 polymerase chain reaction was positive. Despite inpatient treatment for COVID-19 and a perianal abscess, the patient acutely decompensated, with worsening fever, tachycardia, fluid-refractory hypotension, elevation of liver enzymes, and transformation of the rash into purpura extending from the face to the trunk, upper and lower extremities, including the palmar and plantar surfaces of the hands and feet. Cytokine profile revealed rising levels of interleukin (IL)-6, IL-8, and TNF-α, higher than those described in either inflammatory bowel disease or severe COVID-19 alone. The patient was treated with infliximab for TNF-α blockade to address both moderately to severely active Crohn disease and multisystem inflammatory syndrome in children temporally related to COVID-19. Within hours of infliximab treatment, fever, tachycardia, and hypotension resolved. Cytokine profile improved with normalization of TNF-α, a decrease in IL-6, and IL-8 concentrations. This case supports a role for blockade of TNF-α in the treatment of COVID-19 inflammatory cascade. The role of anti-TNF agents in patients with multisystem inflammatory syndrome in children temporally related to COVID-19 requires further investigation. |
| 2020 | Reevaluation of Lung Injury in TNF-Induced Shock: The Role of the Acid Sphingomyelinase. | Mediators Inflamm | Tumor necrosis factor (TNF) is a well-known mediator of sepsis. In many cases, sepsis results in multiple organ injury including the lung with acute respiratory distress syndrome (ARDS). More than 20-year-old studies have suggested that TNF may be directly responsible for organ injury during sepsis. However, these old studies are inconclusive, because they relied on human rather than conspecific TNF, which was contaminated with endotoxin in most studies. In this study, we characterized the direct effects of intravenous murine endotoxin-free TNF on cardiovascular functions and organ injury in mice with a particular focus on the lungs. Because of the relevance of the acid sphingomyelinase in sepsis, ARDS, and caspase-independent cell death, we also included acid sphingomyelinase-deficient (ASM) mice. ASM and wild-type (WT) mice received 50 g endotoxin-free murine TNF intravenously alone or in combination with the pan-caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (zVAD) and were ventilated at low tidal volume while lung mechanics were followed. Blood pressure was stabilized by intra-arterial fluid support, and body temperature was kept at 37°C to delay lethal shock and to allow investigation of blood gases, lung histopathology, proinflammatory mediators, and microvascular permeability 6 hours after TNF application. Besides the lungs, also the kidneys and liver were examined. TNF elicited the release of inflammatory mediators and a high mortality rate, but failed to injure the lungs, kidneys, or liver of healthy mice significantly within 6 hours. Mortality in WT mice was most likely due to sepsis-like shock, as indicated by metabolic acidosis, high procalcitonin levels, and cardiovascular failure. ASM mice were protected from TNF-induced hypotension and reflex tachycardia and also from mortality. In WT mice, intravenous exogenous TNF does not cause organ injury but induces a systemic inflammatory response with cardiovascular failure, in which the ASM plays a role. |
| 2020 | Dexmedetomidine with sufentanil in intravenous patient-controlled analgesia for relief from postoperative pain, inflammation and delirium after esophageal cancer surgery. | Biosci Rep | Postoperative pain can cause serious adverse reactions that severely affect postoperative outcome. The present study evaluated the effect of dexmedetomidine (DEX) added to sufentanil in intravenous patient-controlled analgesia (PCA) on the relief of pain and inflammatory responses during postoperative recovery of patients undergoing a combined thoracoscopic-laparoscopic esophagectomy (TLE).Sixty patients undergoing TLE were randomly allocated to receive 1 μg/ml of sufentanil alone (Group S) or 1 μg/ml of sufentanil plus 2.5 μg/ml of DEX (Group D) for postoperative intravenous (IV) PCA. Postoperative pain relief, cumulative PCA requirements, inflammatory marker levels, delirium and recovery were assessed.A joint DEX and sufentanil regimen significantly reduced the area under the curve of numerical rating scores for pain at rest (NRSR) and coughing (NRSC) at 1-48 h postoperatively (P = 0.000) that were associated with lower PCA-delivered cumulative sufentanil consumption and less PCA frequency until 48 h postoperatively (P < 0.05 and P < 0.0001, respectively). The simultaneous administration of DEX and sufentanil significantly reduced plasma IL-6 and TNF-α concentrations and increased IL-10 level (P < 0.0001, P = 0.0003 and P = 0.0345, respectively), accompanied by better postoperative delirium categories and health statuses of patients (P = 0.024 and P < 0.05, respectively). There was no hypotension, bradycardia, respiratory depression or oversedation in Group D.Patients receiving DEX in addition to IV PCA sufentanil for TLE exhibited better postoperative analgesia, fewer inflammatory responses and lower postoperative delirium categories and better health statuses. |
| 2020 | Central angiotensin-(1-7) attenuates systemic inflammation via activation of sympathetic signaling in endotoxemic rats. | Brain Behav Immun | Angiotensin-(1-7) [Ang-(1-7)] is an angiotensin-derived neuropeptide with potential anti-hypertensive and anti-inflammatory properties. However, a possible action of Ang-(1-7) in neuroimmune interactions to regulate inflammatory response has not been explored. Thus, the aim of this study was to determine whether the intracerebroventricular (i.c.v.) administration of Ang-(1-7) can modulate systemic inflammation via sympathetic efferent circuits. Wistar male rats received systemic administration of lipopolysaccharide (LPS) (1.5 mg/Kg). Ang-(1-7) (0.3 nmol in 2 µL) promoted the release of splenic norepinephrine and attenuated tumor necrosis factor (TNF) and nitric oxide (NO), but increased interleukin-10 (IL-10), levels in the serum, spleen, and liver in endotoxemic rats. Furthermore, 6-hydroxydopamine-induced chemical sympathectomy (100 mg/Kg, intravenous) or i.c.v. administration of Mas receptor antagonist A779 (3 nmol in 2 µL) abolished the anti-inflammatory effects of central Ang-(1-7) injection. Moreover, this treatment did not alter the plasmatic LPS-induced corticosterone and vasopressin. The administration of Ang-(1-7) reverted the low resistance in response to catecholamines of rings of thoracic aorta isolated from endotoxemic rats, treated or not, with this peptide by a mechanism dependent on the regulation of NO released from perivascular adipose tissue. Together, our results indicate that Ang-(1-7) regulates systemic inflammation and vascular hyporesponsiveness in endotoxemia via activation of a central Mas receptors/sympathetic circuits/norepinephrine axis and provide novel mechanistic insights into the anti-inflammatory Ang-(1-7) properties. |
| 2020 | Tumor necrosis factor inhibition attenuates white matter gliosis after systemic inflammation in preterm fetal sheep. | J Neuroinflammation | Increased circulating levels of tumor necrosis factor (TNF) are associated with greater risk of impaired neurodevelopment after preterm birth. In this study, we tested the hypothesis that systemic TNF inhibition, using the soluble TNF receptor Etanercept, would attenuate neuroinflammation in preterm fetal sheep exposed to lipopolysaccharide (LPS).Chronically instrumented preterm fetal sheep at 0.7 of gestation were randomly assigned to receive saline (control; n = 7), LPS infusion (100 ng/kg i.v. over 24 h then 250 ng/kg/24 h for 96 h plus 1 μg LPS boluses at 48, 72, and 96 h, to induce inflammation; n = 8) or LPS plus two i.v. infusions of Etanercept (2 doses, 5 mg/kg infused over 30 min, 48 h apart) started immediately before LPS-exposure (n = 8). Sheep were killed 10 days after starting infusions, for histology.LPS boluses were associated with increased circulating TNF, interleukin (IL)-6 and IL-10, electroencephalogram (EEG) suppression, hypotension, tachycardia, and increased carotid artery perfusion (P < 0.05 vs. control). In the periventricular and intragyral white matter, LPS exposure increased gliosis, TNF-positive cells, total oligodendrocytes, and cell proliferation (P < 0.05 vs control), but did not affect myelin expression or numbers of neurons in the cortex and subcortical regions. Etanercept delayed the rise in circulating IL-6, prolonged the increase in IL-10 (P < 0.05 vs. LPS), and attenuated EEG suppression, hypotension, and tachycardia after LPS boluses. Histologically, Etanercept normalized LPS-induced gliosis, and increase in TNF-positive cells, proliferation, and total oligodendrocytes.TNF inhibition markedly attenuated white matter gliosis but did not affect mature oligodendrocytes after prolonged systemic inflammation in preterm fetal sheep. Further studies of long-term brain maturation are now needed. |
| 2020 | Parecoxib exhibits anti-inflammatory and neuroprotective effects in a rat model of transient global cerebral ischemia. | J Toxicol Environ Health A | Transient global cerebral ischemia (tGCI) induces inflammation leading to secondary brain injury. Data suggested that cyclooxygenase-2 (COX-2) is involved in the occurrence and development of inflammatory reaction after reperfusion; however, the effectiveness of a highly selective COX-2 inhibitor, parecoxib, to counteract tGCI remains to be determined. Thus, the aim of this study was to investigate the potential protective actions of parecoxib in a rat model of tGCI and the role inflammation plays in this disorder. Adult male Sprague-Dawley rats were administered parecoxib 10 or 20 mg/kg intraperitoneally (ip) at 5 min, 24 or 48 hr after tGCI. Control rats received an equal volume of 0.9% saline. The rat model of tGCI was established using the method of bilateral common carotid artery occlusion combined with arterial hypotension. The following parameters were measured: Neurological Severity Score, morphological changes in the hippocampal region, Evans blue (, brain water content, levels of matrix metalloproteinase-9 (MMP-9), zonula occludens-1 (ZO-1), neuronal apoptosis, the protein expression of Bcl-2, Bax, COX-2, prostaglandin E2 (), interleukin-1β (-1β), and tumor necrosis factor-α (-α). Parecoxib treatment significantly improved neurological function and morphological defects in the hippocampal region, reduced levels of COX-2, -1β, and -α. In addition, parecoxib attenuated brain edema and BBB destruction as evidenced by increased ZO-1 expression and decreased MMP-9 expression. Further, parecoxib reduced neuronal apoptosis via diminished protein expression of Bax and enhanced expression of Bcl-2. |
| 2019 | Acute Increase in -GlcNAc Improves Survival in Mice With LPS-Induced Systemic Inflammatory Response Syndrome. | Front Physiol | Sepsis is a systemic inflammatory response syndrome (SIRS) resulting from a severe infection that is characterized by immune dysregulation, cardiovascular derangements, and end-organ dysfunction. The modification of proteins by -linked N-acetylglucosamine (-GlcNAcylation) influences many of the key processes that are altered during sepsis, including the production of inflammatory mediators and vascular contractility. Here, we investigated whether -GlcNAc affects the inflammatory response and cardiovascular dysfunction associated with sepsis. Mice received an intraperitoneal injection of lipopolysaccharide (LPS, 20 mg/Kg) to induce endotoxic shock and systemic inflammation, resembling sepsis-induced SIRS. The effects of an acute increase in -GlcNAcylation, by treatment of mice with glucosamine (GlcN, 300 mg/Kg, i.v.) or thiamet-G (ThG, 150 μg/Kg, i.v.), on LPS-associated mortality, production and release of cytokines by macrophages and vascular cells, vascular responsiveness to constrictors and blood pressure were then determined. Mice under LPS-induced SIRS exhibited a systemic and local inflammatory response with increased levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor (TNF-α), as well as severe hypotension and vascular hyporesponsiveness, characterized by reduced vasoconstriction to phenylephrine. In addition, LPS increased neutrophil infiltration in lungs and produced significant lethality. Treatment with GlcN and ThG reduced systemic inflammation and attenuated hypotension and the vascular refractoriness to phenylephrine, improving survival. GlcN and ThG also decreased LPS-induced production of inflammatory cytokines by bone marrow-derived macrophages and nuclear transcription factor-kappa B (NF-κB) activation in RAW 264.7 NF-κB promoter macrophages. Treatment of mice with ThG increased -glycosylation of NF-κB p65 subunit in mesenteric arteries, which was associated with reduced Ser phosphorylation of NF-κB p65. Finally, GlcN also increased survival rates in mice submitted to cecal ligation and puncture (CLP), a sepsis model. In conclusion, increased -GlcNAc reduces systemic inflammation and cardiovascular disfunction in experimental sepsis models, pointing this pathway as a potential target for therapeutic intervention. |
| 2019 | Bioinformatics Analysis of Gene Expression Profiles for Risk Prediction in Patients with Septic Shock. | Med Sci Monit | BACKGROUND Septic shock occurs when sepsis is associated with critically low blood pressure, and has a high mortality rate. This study aimed to undertake a bioinformatics analysis of gene expression profiles for risk prediction in septic shock. MATERIAL AND METHODS Two good quality datasets associated with septic shock were downloaded from the Gene Expression Omnibus (GEO) database, GSE64457 and GSE57065. Patients with septic shock had both sepsis and hypotension, and a normal control group was included. The differentially expressed genes (DEGs) were identified using OmicShare tools based on R. Functional enrichment of DEGs was analyzed using DAVID. The protein-protein interaction (PPI) network was established using STRING. Survival curves of key genes were constructed using GraphPad Prism version 7.0. Each putative central gene was analyzed by receiver operating characteristic (ROC) curves using MedCalc statistical software. RESULTS GSE64457 and GSE57065 included 130 RNA samples derived from whole blood from 97 patients with septic shock and 33 healthy volunteers to obtain 975 DEGs, 455 of which were significantly down-regulated and 520 were significantly upregulated (P<0.05). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identified significantly enriched DEGs in four signaling pathways, MAPK, TNF, HIF-1, and insulin. Six genes, WDR82, ASH1L, NCOA1, TPR, SF1, and CREBBP in the center of the PPI network were associated with septic shock, according to survival curve and ROC analysis. CONCLUSIONS Bioinformatics analysis of gene expression profiles identified four signaling pathways and six genes, potentially representing molecular mechanisms for the occurrence, progression, and risk prediction in septic shock. |
| 2019 | Anti-inflammatory effect of mushrooms in dengue-infected human monocytes. | Trop Biomed | Pathogenesis of dengue fever has been associated with the activation of the cytokine cascade that triggered inflammatory responses. The inflammatory reactions in dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS) are the main cause of haemorrhagic manifestations, coagulation disorders, vascular permeability, hypotension and shock which could exacerbate the condition of the disease. In an earlier study, extracts belonging to Lignosus rhinocerotis, Pleurotus giganteus, Hericium erinaceus, Schizophyllum commune and Ganoderma lucidium mushrooms were screened for antidengue virus activities. We found that hot aqueous extract (HAE) and aqueous soluble separated from ethanol extract (ASE) exhibited their potential to reduce dengue viral load which were observed in plaque reduction assay and real-time RT-PCR. In continuation of our previous findings, this study was initiated to further investigate the other aspect; the anti-inflammatory activities of HAE and ASE of L. rhinocerotis, P. giganteus, H. erinaceus, S. commune and G. lucidium on human monocytes infected with dengue virus-2 (DENV-2) New guinea C strain. Human monocytes infected with DENV-2 were treated with mushroom extracts for 48 hours. The cytokine profile coincides with dengue infection, i.e. IFN-γ, TNF-α, IL-1β, IL-6, IL-8, and IL-10 were measured by BD OptEIATM Elisa Kit. The expression of these cytokines was significantly elevated in untreated infected cells two days after infection. However, after treated with mushroom extracts prominent anti-inflammatory effect were detected towards IFN-γ, IL-10, TNF-α, IL-6, and IL-1β. The most significant anti-inflammatory effects were detected in HAE of G. lucidium, S. commune, P. giganteus and ASE of L. rhinocerotis and the effects were comparable with dexamethasone, the reference inhibitor. These results demonstrated that mushroom HAE or ASE could successfully have suppressed cytokine production in dengue-infected monocytes and has a great potential to develop an antiinflammatory agent from mushroom extract for the treatment of dengue infection. |
| GALLIC ACID IMPROVES OXIDATIVE STRESS AND INFLAMMATION THROUGH REGULATING MICRORNAS EXPRESSIONS IN THE BLOOD OF DIABETIC RATS. | Acta Endocrinol (Buchar) | Endothelial dysfunction and diabetic cardiomyopathy are critical complications of diabetes. Gallic acid (GA) plays a significant role in cardiovascular disorders resulted from diabetes. In addition, increased plasma miR-24, miR-126 associated with endothelial dysfunction.The current study was designed to assess the effects of GA on plasma miR-24, miR-126 levels in the diabetic rats.Adult male Sprague-Dawley rats were divided into three groups (n=8): control (C), diabetic (D) and diabetic group treated with GA (D+G, 25 mg/kg, by gavage) for eight weeks. The blood glucose level, body weight, lipid profile, blood pressure, plasma miR-24 and miR-126 levels, antioxidant and inflammatory biomarkers were measured.The plasma levels of miR-24, miR-126, body weight, high-density lipoprotein cholesterol (HDL-c), total anti-oxidant capacity (TAC) and the systolic blood pressure significantly reduced and blood glucose, total cholesterol (TC), triglycerides (TG), very low-density lipoprotein cholesterol (VLDL-c), malondialdehyde (MDA), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and low-density lipoprotein cholesterol (LDL-c) significantly elevated among the diabetic rats compared with the control group. However, GA restored body weight, blood pressure, TC, TG, VLDL-c, TNF-α, miR-126, blood glucose, HDL-c, MDA, TAC, miR-24 and IL-6 among the GA treated rats compared with the diabetic group.GA improves inflammation, oxidative stress and hypotension result from diabetes. These protective effects are probably mediated via increasing plasma miR-24 and miR-126 levels. |
| 2019 | Pathophysiologic Characterization of a Novel Rabbit Model of Biliary Tract Infection-Derived Sepsis. | Sci Rep | Biliary tract infection (BTI)-derived sepsis remains a serious problem with significant morbidity and mortality in the modern era of critical care management. Current animal models of BTI have relied mostly on injecting purified bacteria or their toxins into the biliary tract. These models do not fully reflect pathophysiology or disease processes of clinical cholangitis or cholecystitis. In the current study, we developed a novel model of BTI by performing cholecystocolonic anastomosis (CCA) in rabbits and characterized pathophysiologic changes in this model. This model is intended to mimic the clinical process of cholecystocolonic fistula with reflux cholangitis, a severe form of BTI. Adult male rabbits were subjected to BTI-derived sepsis through an anastomosis of the gall bladder to the colon (i.e., CCA). The animals were monitored for 7 days to record survival. In additional groups of animals, various bacterial, hemodynamic, histological and biochemical parameters were measured at 12, 24, 48 and 72 h after CCA. The anastomosis between the gallbladder and the colon required about 5-8 min to finish. The median survival time for rabbits after CCA was 96 h. The positive rates of bacterial culture at 72 h after CCA were 83.3% and 100% in the blood and liver, respectively. The most common microorganism was Escherichia coli followed by Enterococcus. Plasma Tumor Necrosis Factor-α (TNF-α), Lnterleukin-10 (IL-10), Lnterleukin-6 (IL-6), and High-mobility group box 1 protein (HMGB-1) levels were greatly elevated after CCA. The cardiac index and heart rate increased slightly at 12 h after CCA and then continued to decrease. Systemic hypotension developed 48 h after CCA. Histological studies showed reflux cholangitis with acute lung and kidney injury. Cholecystocolonic anastomosis produces polymicrobial sepsis in rabbits, which mimics many aspects of human BTI-derived sepsis. It is reproducible and easy to perform and may serve as an excellent model for future sepsis research. |
| 2019 | Infliximab Induced Cardiac Tamponade | Ir Med J | AimTo report the first case of cardiac tamponade related to Infliximab induction therapy in an Ulcerative Colitis patient.MethodsReview of published case reports.ResultsThis complication was likely due to a type 3 hypersensitivity immune-complex reaction resulting in a reactive pericardial effusionDiscussionThough rare, this case demonstrates how autoimmune reaction to anti-TNF𝛼 therapy can initially mimic infection, as our patient presented with tachycardia, hypotension, raised inflammatory and infective markers and fever. |
| 2019 | Cytokine clearance with CytoSorb® during cardiac surgery: a pilot randomized controlled trial. | Crit Care | Cardiopulmonary bypass (CPB) is often associated with degrees of complex inflammatory response mediated by various cytokines. This response can, in severe cases, lead to systemic hypotension and organ dysfunction. Cytokine removal might therefore improve outcomes of patients undergoing cardiac surgery. CytoSorb® (Cytosorbents, NJ, USA) is a recent device designed to remove cytokine from the blood using haemoadsorption (HA). This trial aims to evaluate the potential of CytoSorb® to decrease peri-operative cytokine levels in cardiac surgery.We have conducted a single-centre pilot randomized controlled trial in 30 patients undergoing elective cardiac surgery and deemed at risk of complications. Patients were randomly allocated to either standard of care (n = 15) or CytoSorb® HA (n = 15) during cardiopulmonary bypass (CPB). Our primary outcome was the difference between the two groups in cytokines levels (IL-1a, IL-1b, IL-2, IL-4, IL-5, IL-6, IL-10, TNF-α, IFN-γ, MCP-1) measured at anaesthesia induction, at the end of CPB, as well as 6 and 24 h post-CPB initiation. In a consecutive subgroup of patients (10 in HA group, 11 in control group), we performed cross-adsorber as well as serial measurements of coagulation factors' activity (antithrombin, von Willebrand factor, factor II, V, VIII, IX, XI, and XII).Both groups were similar in terms of baseline and peri-operative characteristics. CytoSorb® HA during CPB was not associated with an increased incidence of adverse event. The procedure did not result in significant coagulation factors' adsorption but only some signs of coagulation activation. However, the intervention was associated neither with a decrease in pro- or anti-inflammatory cytokine levels nor with any improvement in relevant clinical outcomes.CytoSorb® HA during CPB was not associated with a decrease in pro- or anti-inflammatory cytokines nor with an improvement in relevant clinical outcomes. The procedure was feasible and safe. Further studies should evaluate the efficacy of CytoSorb® HA in other clinical contexts.ClinicalTrials.gov NCT02775123 . Registered 17 May 2016. |
| 2019 | Transcriptional Suppression of CPI-17 Gene Expression in Vascular Smooth Muscle Cells by Tumor Necrosis Factor, Krüppel-Like Factor 4, and Sp1 Is Associated with Lipopolysaccharide-Induced Vascular Hypocontractility, Hypotension, and Mortality. | Mol Cell Biol | Vasodilatory shock in sepsis is caused by the failure of the vasculature to respond to vasopressors, which results in hypotension, multiorgan failure, and ultimately patient death. Recently, it was reported that CPI-17, a key player in the regulation of smooth muscle contraction, was downregulated by lipopolysaccharide (LPS) in mesenteric arteries concordant with vascular hypocontractilty. While Sp1 has been shown to activate CPI-17 transcription, it is unknown whether Sp1 is involved in LPS-induced smooth muscle CPI-17 downregulation. Here we report that tumor necrosis factor (TNF) was critical for LPS-induced smooth muscle CPI-17 downregulation. Mechanistically, we identified two GC boxes as a key TNF response element in the CPI-17 promoter and demonstrated that KLF4 was upregulated by TNF, competed with Sp1 for the binding to the GC boxes in the CPI-17 promoter, and repressed CPI-17 transcription through histone deacetylases (HDACs). Moreover, genetic deletion of TNF or pharmacological inhibition of HDACs protected mice from LPS-induced smooth muscle CPI-17 downregulation, vascular hypocontractility, hypotension, and mortality. In summary, these data provide a novel mechanism of the transcriptional control of CPI-17 in vascular smooth muscle cells under inflammatory conditions and suggest a new potential therapeutic strategy for the treatment of vasodilatory shock in sepsis. |
| 2019 | Central serotonin prevents hypotension and hypothermia and reduces plasma and spleen cytokine levels during systemic inflammation. | Brain Behav Immun | An exceptionally high mortality rate is observed in sepsis and septic shock. Systemic administration of lipopolysaccharide (LPS) has been used as an experimental model for sepsis resulting in an exacerbated immune response, brain neurochemistry adjustments, hypotension, and hypothermia followed by fever. Central serotonergic pathways not only modulate systemic inflammation (SI) but also are affected by SI, including in the anteroventral region of the hypothalamus (AVPO), which is the hierarchically most important region for body temperature (Tb) control. In this study, we sought to determine if central serotonin (5-HT) plays a role in SI induced by intravenous administration of LPS (1.5 mg/kg) in male Wistar rats (280-350 g) by assessing 5-HT levels in the AVPO, mean arterial pressure, heart rate, and Tb up to 300 min after LPS administration, as well as assessing plasma and spleen cytokine levels, nitric oxide (NO) plasma levels, and prostaglandin (PG) E levels in the AVPO at 75 min and 300 min after LPS administration. We observed reduced AVPO 5-HT levels, hypotension, tachycardia, hypothermia followed by fever, as well as observing increased plasma NO, plasma and spleen cytokines and AVPO PGE levels in SI. Intracerebroventricular (icv) administration of 5-HT 30 min before LPS administration prevented hypotension and hypothermia, which were accompanied by reduced plasma NO, as well as plasma TNF-α, IL-1β, IL-6, and IL-10 and spleen TNF-α and IL-10 levels. We suggest that SI reduced 5-HT levels in the AVPO favor an increased pro-inflammatory status both centrally and peripherally that converge to hypotension and hypothermia. Moreover, our results are consistent with the notion that exogenous 5-HT given icv prevents hypotension and hypothermia probably activating the splenic anti-inflammatory pathway. |
| 2019 | Genetic variability of inflammation and oxidative stress genes does not play a major role in the occurrence of adverse events of dopaminergic treatment in Parkinson's disease. | J Neuroinflammation | Inflammation and oxidative stress are recognized as important contributors to Parkinson's disease pathogenesis. As such, genetic variability in these pathways could have a role in susceptibility for the disease as well as in the treatment outcome. Dopaminergic treatment is effective in management of motor symptoms, but poses a risk for motor and non-motor adverse events. Our aim was to evaluate the impact of selected single-nucleotide polymorphisms in genes involved in inflammation and oxidative stress on Parkinson's disease susceptibility and the occurrence of adverse events of dopaminergic treatment.In total, 224 patients were enrolled, and their demographic and clinical data on the disease course were collected. Furthermore, a control group of 146 healthy Slovenian blood donors were included for Parkinson's disease' risk evaluation. Peripheral blood was obtained for DNA isolation. Genotyping was performed for NLRP3 rs35829419, CARD8 rs2043211, IL1β rs16944, IL1β rs1143623, IL6 rs1800795, CAT rs1001179, CAT rs10836235, SOD2 rs4880, NOS1 rs2293054, NOS1 rs2682826, TNF-α rs1800629, and GPX1 rs1050450. Logistic regression was used for analysis of possible associations.We observed a nominally significant association of the IL1β rs1143623 C allele with the risk for Parkinson's disease (OR = 0.59; 95%CI = 0.38-0.92, p = 0.021). CAT rs1001179 A allele was significantly associated with peripheral edema (OR = 0.32; 95%CI = 0.15-0.68; p = 0.003). Other associations observed were only nominally significant after adjustments: NOS1 rs2682826 A allele and excessive daytime sleepiness and sleep attacks (OR = 1.75; 95%CI = 1.00-3.06, p = 0.048), SOD2 rs4880 T allele and nausea/vomiting (OR = 0.49, 95%CI = 0.25-0.94; p = 0.031), IL1β rs1143623 C allele and orthostatic hypotension (OR = 0.57, 95%CI = 0.32-1.00, p = 0.050), and NOS1 rs2682826 A allele and impulse control disorders (OR = 2.59; 95%CI = 1.09-6.19; p = 0.032). We did not find any associations between selected polymorphisms and motor adverse events.Apart from some nominally significant associations, one significant association between CAT genetic variability and peripheral edema was observed as well. Therefore, the results of our study suggest some links between genetic variability in inflammation- and oxidative stress-related pathways and non-motor adverse events of dopaminergic treatment. However, the investigated polymorphisms do not play a major role in the occurrence of the disease and the adverse events of dopaminergic treatment. |
| 2019 | Intravenous injection of post-hemorrhagic shock mesenteric lymph induces multiple organ injury in rats. | Exp Ther Med | Post-hemorrhagic shock mesenteric lymph (PHSML) has an important role in the multiple organ injuries caused by severe shock. The current study investigated whether intravenous injection of PHSML induces organ injury in normal rats. Following the establishment of hemorrhagic shock in donor rats (40±2 mmHg, 3 h), PHSML was drained during hypotension at 1-3 h and then injected to normal rats through the femoral vein within 30 min. The mean arterial pressure (MAP) was measured, and samples were obtained for analysis of histology and biochemical indices at 2.5 h post-PHSML administration. PHSML administration resulted in a significant decrease in MAP at the early and late stage of the experiment. Structural damage of the lung, kidney, heart and liver was also observed, and the levels of urea, creatinine, aspartate aminotransferase, total bile acid and creatine kinase MB isoenzyme were increased in the plasma. Additionally, PHSML injection significantly increased the levels of trypsin, tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 and receptor of advanced glycation end-products in the plasma, malondialdehyde in the lung and myocardium, and TNF-α in the lung, kidney, myocardium and liver. Intravenous injection of PHSML induced multiple organ injury in normal rats via increases in trypsin activity, inflammatory factors and free radical production. The findings indicate that PHSML return is an important contributor to organ damage following hemorrhagic shock. |
| 2018 | Preventive Leptin Administration Protects Against Sepsis Through Improving Hypotension, Tachycardia, Oxidative Stress Burst, Multiple Organ Dysfunction, and Increasing Survival. | Front Physiol | Sepsis syndrome is the most important cause of mortality in critically ill patients admitted to intensive care units (ICUs). However, current therapies for its prevention and treatment are still unsatisfactory, and the mortality rate is still high. Non-septic ICU patients are vulnerable to acquire sepsis syndrome. Thus, a preventive treatment for this population is needed. During sepsis syndrome and endotoxemia, severe hypotension, tachycardia, oxidative and immune response increase, multiple organ dysfunction syndrome (MODS) and decreased survival are observed. Leptin administration protects against negative effects of sepsis syndrome and endotoxemia. Furthermore, it is has been reported that leptin elevates blood pressure mediated by sympathetic nervous system activation. However, whether leptin administration before sepsis induction mediates its protective effects during sepsis through blood pressure regulation is not known. Therefore, we investigated whether pre-treatment of leptin improves blood pressure and MODS, resulting in survival increase during endotoxemia. The results showed that leptin administration before endotoxemia induction reduced both the hypotension and tachycardia characteristically observed during endotoxemia. Notably, this protective effect was observed early and late in the course of endotoxemia. Endotoxemia-induced MODS decreased in leptin-treated rats, which was reflected in normal values for liver and kidney function, inhibition of muscle mass wasting and maintenance of glycemia. Furthermore, leptin pre-treatment decreased the oxidative stress burst in blood and blunted the increased pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 observed during endotoxemia. Remarkably, according to the leptin-induced increase in survival, leptin pre-administration decreased the risk for death associated with sepsis syndrome at early and late times after endotoxemia induction. These results show a potential preventive therapy against sepsis syndrome and endotoxemia in vulnerable patients, based in the beneficial actions of leptin. |
| 2018 | A novel blood pressure modulator C1q/TNF-α-related protein 1 (CTRP1). | BMB Rep | C1q/TNF-α-Related Protein 1 (CTRP1) has recently been shown to act as a blood pressure regulator, as it induces vasoconstriction. In the aorta, CTRP1 facilitates recruitment of angiotensin II receptor 1 (AT1R) to plasma membrane, through activation of the AKT/AS160 signaling pathway. This leads to activation of the Ras homolog gene family (Rho)/Rho kinase (ROCK) signaling pathway, resulting in vasoconstriction. Accordingly, mice overexpressing Ctrp1 have hypertensive phenotype. Patients with hypertension also display higher circulating CTRP1 levels, compared to healthy individuals, indicating that excessive CTRP1 may affect development of hypertension. Conversely, CTRP1 is regarded as an 'innate blood pressure modulator' because CTRP1 increases blood pressure under dehydration to prevent hypotension. Mice lacking Ctrp1 fail to maintain normotension under dehydration conditions, resulting in hypotension, suggesting that CTRP1 is an essential protein for maintaining blood pressure homeostasis. In conclusion, CTRP1 is a novel, anti-hypotensive vasoconstrictor that increases blood pressure during dehydrationinduced hypotension. [BMB Reports 2018; 51(12): 611-612]. |
| 2018 | A Case of Generalized, Superinfected Dermatitis and Inguinal Mycobacterium Lymphadenitis - TB or not TB? | Acta Dermatovenerol Croat | Dear Editor, Eczema is an inflammatory dermatitis mediated by cellular immunity, with an etiology in which environmental, immunological, and genetic factors are involved. Skin inflammation through proinflammatory cytokines creates a favorable environment for microbial antigens and optimal conditions for infection (1). In case of underlying immunosuppression, inflammatory features of dermatitis and superimposed infections are more severe. The presence of minor trauma of the skin in the form of fissures can favor both easier inoculation of some bacterial germs, leading to a dermatitis superinfection, and/or the transcutaneous inoculation of atypical mycobacteria, with a possibility of developing localized types of tuberculous lymphadenitis (TLA). TLA, the localized type of systemic tuberculosis (TB) infection, is the most common form of extra-pulmonary TB in developing countries (2), while lymphadenitis due to atypical mycobacteria is a localized disease, more frequently seen in developed countries (3,4). In tuberculosis, the transmission of Mycobacterium tuberculosis is airborne, while in atypical mycobacterium lymphadenitis transmission can be both airborne or by ingestion or inoculation (5). In both forms of TB, lymphadenopathy evolves towards abscess and presents fibrotic scars or calcifications upon healing (6). A positive diagnosis involves a clinical and epidemiological investigation, a purified protein derivative (PPD) skin test, ultrasound, and CT / MRI of lymph node masses. A lymph node biopsy is used to confirm the diagnosis of TB and PCR, while positive culture confirms the etiology of TB lymphadenitis. The differential diagnosis of TLA is difficult: neoplastic, bacterial, or viral and fungal infections, sarcoidosis, Castleman's disease, drug reactions, etc. (5). TB-induced immunosuppression may favor the development of fungal and bacterial infections, sometimes severe and poorly responsive to treatment. On the other hand, immunosuppressive conditions increase the risk of extra-pulmonary TB (2). A 40-year old woman who had experienced recurrent episodes of dermatitis over the previous 7 years was hospitalized with fever, malaise, and a disseminated erythematous and crusted, exudative, and flexural itching rash (Figure 1). There were fetid, purulent secretions at the conjunctival, auricular, genital, and umbilical areas. The clinical exam also revealed lymphadenopathy syndrome (large, painful submandibular, cervical, and axillar bilateral lymph nodes; an indurated, painful, and adherent left inguinal lymph node of 5-6 cm). Microbial cultures isolated multiple multi-drug-resistant bacteria (SAH-MRSA, Acinetobacter baumannii, Enterococcus faecalis, E. coli, Enterobacter) and Candida albicans in the oral cavity and conjunctival, auricular, nasal, umbilical, and genital areas. The skin biopsy confirmed the diagnosis of dermatitis. PPD skin test was 21 mm. Other tests (HIV and syphilis serology, blood culture, chest X-ray) were negative. Systemic treatment with vancomycin, metronidazole, fluconazole, local antiseptic compresses, and topical corticosteroid ointments was initiated. 2 days after starting the treatment with vancomycin, Redman syndrome occurred (headache, dyspnea, colicky pains, myalgia, rush, fever (39 °C), hypotension (80/40 mmHg), and tachycardia (100 bpm)). This syndrome resolved upon discontinuation of Vancomycin. Further treatment with imipenem/cilastatinand linezolid for 14 days lead to a favorable response with amelioration of the symptoms. Biopsy of the submandibular lymph node raised the suspicion of Castleman's disease; however, due to the overall incomplete clinical picture (no night sweats, no weight reduction, lack of hepatosplenomegaly and peripheral neuropathy), we decided to perform a biopsy of an inguinal lymph node. The histopathological aspect suggested TLA (lymphoid hyperplasia predominantly diffuse, reactive, presenting tuberculous follicles with central caseous necrosis) (Figure 2). A combination of specific antituberculous drugs (isoniazid, rifampicin, pyrazinamide, and ethambutol) for 6 months resolved the lymphadenopathy syndrome with no further recurrence of eczema and skin infections. Certain delayed hypersensitivity mechanisms are involved both in dermatitis and in TB. CD4 lymphocytes are the primary mediators of anti-TB immunity, while proinflammatory cytokines mediate the activation of macrophages involved in controlling bacillary growth (1). In cases of superinfected dermatitis, microbial exotoxins penetrate the skin barrier more easily due to inflammation. Released cytokines (IL-1, TNF, and IL12) favor the expression of E-selectin on endothelial vascular growth factor and on skin lymphocyte antigen expression, with amplification of initial skin inflammation and creating favorable conditions for microbial colonization and infection (7). The common denominator in dermatitis and TB are the circulating immune complexes (up to 56% of TB cases), which are formed by the interaction between an antibody and bacterial antigen (8), which was in this case evidenced by increased levels of IgA and IgG. In our case, the frequent recurrences of infected dermatitis with multiple multi-drug-resistant germs that were poorly responsive to treatment and displayed a severe evolution towards generalization as well as the lymphadenopathy and the persistence of a biological inflammatory syndrome indicated that another immunosuppressive cause could be involved. Isolated bacterial and fungal germs changed the immune status of the patient. The risk of mycobacterium infection was increased by the environment they created and the patient's underlying skin inflammation. The diagnosis of TB lymphadenitis was established by the histopathologist, but in the absence of PCR we could not determine whether the TB infection was caused by Mycobacterium tuberculosis or by atypical mycobacteria. Given that there was no evidence of other sites of TB infection, we conjectured that inoculation of mycobacterium took place at the skin lesion and that an atypical mycobacterium might have contributed to the etiology of the TLA. In our case, the anti-tuberculous drugs and skin infection treatment with follow-up of the side-effects led to complete remission of mycobacterium lymphadenitis, dermatitis, and infectious processes, without relapses. In conclusion, in the present case chronic dermatitis alongside infection with multi-drug-resistant germs led to an immunosuppressive status which, when associated with the presence of multiple skin ports of entry, allowed a mycobacterial infection at the inguinal lymph node level. Inguinal TLA induced severe dermatitis and difficulties in diagnosis and treatment. |
| 2019 | Molecular hydrogen potentiates hypothermia and prevents hypotension and fever in LPS-induced systemic inflammation. | Brain Behav Immun | Molecular hydrogen (H) exerts anti-oxidative, anti-apoptotic, and anti-inflammatory effects. Here we tested the hypothesis that H modulates cardiovascular, inflammatory, and thermoregulatory changes in systemic inflammation (SI) induced by lipopolysaccharide (LPS) at different doses (0.1 or 1.5 mg/kg, intravenously, to induce mild or severe SI) in male Wistar rats (250-300 g). LPS or saline was injected immediately before the beginning of 360-minute inhalation of H (2% H, 21% O, balanced with nitrogen) or room air (21% O, balanced with nitrogen). Deep body temperature (Tb) was measured by dataloggers pre-implanted in the peritoneal cavity. H caused no change in cardiovascular, inflammatory parameters, and Tb of control rats (treated with saline). During mild SI, H reduced plasma surges of proinflammatory cytokines (TNF-α and IL-6) while caused an increase in plasma IL-10 (anti-inflammatory cytokine) and prevented fever. During severe SI, H potentiated hypothermia, and prevented fever and hypotension, which coincided with reduced plasma nitric oxide (NO) production. Moreover, H caused a reduction in surges of proinflammatory cytokines (plasma TNF-α and IL-1β) and prostaglandin E [(PGE), in plasma and hypothalamus], and an increase in plasma IL-10. These data are consistent with the notion that H blunts fever in mild SI, and during severe SI potentiates hypothermia, prevents hypotension reducing plasma NO production, and exerts anti-inflammatory effects strong enough to prevent fever by altering febrigenic signaling and ultimately down-modulating hypothalamic PGE production. |
| 2018 | Streptococcal M1 protein induces hyporesponsiveness and cytokine release from human arteries in a fibrinogen-dependent manner: a translational study. | Scand J Trauma Resusc Emerg Med | Streptococcus pyogenes is a Gram positive bacterial species commonly involved in sepsis. Invasive strains express virulence factors such as the M1 protein. M1 protein forms complexes with fibrinogen leading to a cytokine storm in plasma contributing to the development of septic shock and organ failure. In experimental animals M1 protein causes vascular nitric oxide production and hyporesponsiveness to pressors, but it is not known whether it affects the human vascular wall.Human omental arteries obtained during surgery were incubated in vitro with M1 protein or lipopolysaccharide (LPS) as positive control, with or without plasma. After 48 h, contractile response to noradrenaline was measured, and levels of nitrite/nitrate and the cytokines interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α in the incubation medium were measured. A second set of arteries were incubated with or without main components of plasma (immunoglobulin G, albumin or fibrinogen), in the presence of M1 protein followed by cytokine measurement.Artery segments incubated with M1 protein and plasma contracted weaker in response to noradrenaline, and levels of IL-6 and IL-8 were significantly higher compared to after incubation with M1 protein alone. Incubation with M1 protein and fibrinogen resulted in elevated levels of IL-6 and IL-8, while incubation with M1 protein and albumin or immunoglobulin G did not affect the levels. Neither any of the other cytokines nor nitrite/nitrate was detected in the medium in any of the incubation conditions.The study shows that M1 protein of Streptococcus pyogenes has a direct effect on the human vascular wall in the presence of plasma, demonstrated both as a diminished contractile response to noradrenaline and increased cytokine production. The effect of plasma was attributed to fibrinogen. The findings suggest that M1 protein contributes to the development of septic shock through impairment of the contractility of the vascular wall. |
| 2018 | C1q/TNF-α-Related Protein 1 (CTRP1) Maintains Blood Pressure Under Dehydration Conditions. | Circ Res | Circulating CTRP1 (C1q/TNF-α [tumor necrosis factor-α]-related protein 1) levels are increased in hypertensive patients compared with those in healthy subjects. Nonetheless, little is known about the molecular and physiological function of CTRP1 in blood pressure (BP) regulation.To investigate the physiological/pathophysiological role of CTRP1 in BP regulation.CTRP1 production was increased to maintain normotension under dehydration conditions, and this function was impaired in inducible CTRP1 KO (knockout) mice (CTRP1 ). The increase in CTRP1 under dehydration conditions was mediated by glucocorticoids, and the antagonist mifepristone prevented the increase in CTRP1 and attenuated BP recovery. Treatment with a synthetic glucocorticoid increased the transcription, translation, and secretion of CTRP1 from skeletal muscle cells. Functionally, CTRP1 increases BP through the stimulation of the AT1R (Ang II [angiotensin II] receptor 1)-Rho (Ras homolog gene family)/ROCK (Rho kinase)-signaling pathway to induce vasoconstriction. CTRP1 promoted AT1R plasma membrane trafficking through phosphorylation of AKT and AKT substrate of 160 kDa (AS160). In addition, the administration of an AT1R blocker, losartan, recovered the hypertensive phenotype of CTRP1 TG (transgenic) mice.For the first time, we provide evidence that CTRP1 contributes to the regulation of BP homeostasis by preventing dehydration-induced hypotension. |
| 2018 | Additive counteraction by α7 and α4β2-nAChRs of the hypotension and cardiac sympathovagal imbalance evoked by endotoxemia in male rats. | Eur J Pharmacol | The cholinergic antiinflammatory pathway favorably influences end organ damage induced by inflammatory conditions. Here, we hypothesized that α7 and/or α4β2-nicotinic acetylcholine receptors (nAChRs) protect against cardiovascular and autonomic imbalances induced by endotoxemia in rats. We assessed dose-effect relationships of i.v. nicotine (25, 50, or 100 μg/kg), PHA-543613 (α7-nAChR agonist; 0.2 or 2.0 mg/kg), or 5-iodo-A-85380 (5IA, α4β2-nAChRs agonist; 0.01 or 0.1 mg/kg) on cardiovascular and inflammatory responses elicited by lipopolysaccharide (LPS, 10 mg/kg i.v.). The two lower doses of nicotine caused dose-dependent attenuation of hypotensive and tachycardic responses of LPS. Nicotine also reversed LPS-evoked reductions in time-domain indices of heart rate variability (HRV) and spectral measure of cardiac sympathovagal balance. Alternatively, hypotensive and tachycardic effects of LPS were (i) partly and dose-dependently reversed after selective activation of α7 (PHA) or α4β2-nAChRs (5IA), and (ii) completely eliminated after co-treatment with the smaller doses of the two agonists. Further, PHA or 5IA abolished the reducing effect of LPS on time and spectral measures of HRV. Elevations in serum tumor necrosis factor-α (TNF-α) observed in LPS-treated rats were compromised upon co-administration of nicotine, PHA, or 5IA. In conclusion, monomeric α7 or heteromeric α4β2-nAChRs favorably and additively influence inflammatory and associated cardiovascular anomalies induced by endotoxemia. |
| 2018 | Ephedrine hydrochloride protects mice from -induced peritonitis. | Am J Transl Res | is a Gram-positive (G) bacterium that causes a wide range of diseases in humans and livestock. Therefore, the development of innovative and effective therapies is essential for the treatment of -induced severe infections. Ephedrine hydrochloride (EH) is a compound derived from ephedrine and is widely used for the management of cardiovascular diseases and hypotension. The results of our previous studies demonstrated that EH has anti-inflammatory activity in macrophages and protects against endotoxic shock. However, whether EH regulates the function of dendritic cells (DCs) and the immune response in -induced infection is unknown. In this study, the anti-inflammatory and regulatory activity of EH on DCs was evaluated. EH increased the production of anti-inflammatory cytokine IL-10 and decreased the production of proinflammatory cytokines TNF-α and IL-12 in DCs stimulated with peptidoglycan (PGN), the main cell wall component in G bacteria. The PI3K/Akt and p38 MAPK signaling pathways controlled EH-induced IL-10 expression and EH-inhibited TNF-α expression, respectively. The PGN-induced expression of co-stimulatory molecules CD40, CD80, CD86, and MHC class II molecule Iab was down-regulated in DCs by EH. Furthermore, EH protected the liver and kidney and increased the survival rate of mice with -induced peritonitis. In conclusion, EH helps to keep immune homeostasis and alleviate organ damage during -induced peritonitis. Therefore, EH may be a promising drug candidate in the treatment of -induced severe infections and other invasive G bacterial infections. |
| 2018 | Flurbiprofen axetil attenuates cerebral ischemia/reperfusion injury by reducing inflammation in a rat model of transient global cerebral ischemia/reperfusion. | Biosci Rep | Ischemic stroke has been ranked as the second cause of death in patients worldwide. Inflammation which is activated during cerebral ischemia/reperfusion (I/R) is an important mechanism leading to brain injury. The present study aimed to investigate the effect of flurbiprofen axetil on cerebral I/R injury and the role of inflammation in this process. Rats were subjected to sham operation or global cerebral I/R with or without flurbiprofen axetil (5 or 10 mg/kg). Global cerebral ischemia was achieved by occlusion of bilateral common carotid arteries combined with hypotension for 20 min followed by reperfusion for 72 h. Then the neurological deficit score, hippocampal cell apoptosis, levels of aquaporin (AQP) 4, AQP9, intercellular cell adhesion molecule-1 (ICAM-1), nuclear factor-κB (NF-κB), tumor necrosis factor (TNF-α), interleukin-1 β (IL-1β), thromboxane B2 (TXB2), and 6-keto-PGI1α were assessed. After reperfusion, neurological deficit score was significantly increased accompanied by severe neuronal damage (exacerbated morphological deficit, increased terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL)-positive cells and cleaved caspase-3 protein expression in hippocampal CA1 region). Cerebral I/R injury also enhanced expressions of TNF-α, IL-1β, NF-κB, AQP4 and AQP9 as well as TXB2 and TXB2/6-keto-PGI1α. All these changes were reversed by pretreatment with flurbiprofen axetil. Flurbiprofen axetil protects the brain from cerebral I/R injury through reducing inflammation and brain edema. |
| 2018 | Cytokine release syndrome after radiation therapy: case report and review of the literature. | J Immunother Cancer | Cytokine release syndrome (CRS) has been reported after immunologic manipulations, most often through therapeutic monoclonal antibodies. To our knowledge, CRS after radiation therapy (RT) for cancer has not been reported before. The development of unusual clinical signs and symptoms after RT led us to investigate the possibility of CRS after RT and review the medical literature on this topic.A 65 year-old man with untreated chronic lymphocytic leukemia and recurrent, metastatic Merkel cell carcinoma undergoing anti-programmed death 1 (PD1) immunotherapy was referred for palliative RT to sites of progressing metastases. Within hours of each weekly dose of RT, he experienced fever, tachycardia, hypotension, rash, dyspnea, and rigors. Based on clinical suspicion for CRS, blood cytokine measurements were performed 1 h after the second and third dose of RT and demonstrated tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) levels approximately ten-fold higher than normal. These were near normal immediately prior to the third dose of RT, and resolved to normal levels 3 weeks after RT. He experienced rapid regression of irradiated tumors, with development of new sites of metastases soon thereafter. A literature review revealed no clinical cases of CRS after RT for cancer.RT during anti-PD1 immunotherapy in a patient with underlying immune dysfunction appeared to be the putative mediator of an immune process which yielded significant increases in pro-inflammatory cytokines, and produced the clinical symptoms meeting the definition of grade 3 CRS. This case demonstrates the capability of RT to elicit immune-related adverse events. |
| 2017 | Vitamin D Enhances Efficacy of Oral Nifedipine in Treating Preeclampsia with Severe Features: A Double Blinded, Placebo-Controlled and Randomized Clinical Trial. | Front Pharmacol | Vitamin D (VD) has exhibited immunomodulatory role in the pathogenesis of preeclampsia. We hypothesize VD potentiate nifedipine treatment for preeclampsia by shortened the time to control blood pressure and prolong time before subsequent hypertensive crisis. We conduct a randomized trial of 683 primigravid women with preeclampsia, who were assigned to different treatment groups, either nifedipine+placebo or nifedipine+VD orally, by random after screening. Primary endpoints include time to control hypertension and time before another hypertensive crisis. Maternal adverse effects including nausea, vomiting, chest pain, mild headache, dizziness, maternal tachycardia, hypotension or shortness of breath, and neonatal parameters including birth weight and Apgar scores, as well as the minimum number of dosages needed to control hypertension were defined as secondary endpoints. Serum levels of cytokines tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were also examined. There was a marked reduction of the time required to control hypertension and a significant lengthening ( = 0.013) of the time before a new hypertensive crisis in participants received nifedipine+VD treatments (41.8 ± 18.3 min), in comparison with the nifedipine+placebo controls (61.1 ± 15.9 min). In women treated with nifedipine+VD, the minimum number of dosages needed to control hypertension was also lower. With regard to adverse effects, no statistical difference was observed between the two treatment groups. Moreover, treatment with VD increased IL-10 and reduced TNF-α serum levels. VD possesses the potential of serving as a safe and effective adjuvant to oral nifedipine in treating women with preeclampsia against hypertension, possibly through the upregulation of IL-10 and the downregulation of TNF-α. |
| 2018 | Anti-inflammatory effect of a novel locally acting A receptor agonist in a rat model of oxazolone-induced colitis. | Purinergic Signal | Adenosine represents a powerful modulating factor, which has been shown to orchestrate the scope, duration, and remission of the inflammatory response through the activation of four specific receptors, classified as A, A, A, and A, all being widely expressed in a variety of immune cells. Several selective A receptor agonists have displayed anti-inflammatory effects, through the suppression of IL-12, TNF, and IFN-γ production by monocytes and lymphocytes, in the setting of chronic intestinal inflammation. However, the therapeutic application of A receptor agonists remains hindered by the risk of serious cardiovascular adverse effects arising from the wide systemic distribution of A receptors. The present study focused on evaluating the anti-inflammatory effects of the novel poorly absorbed A receptor agonist PSB-0777 in a rat model of oxazolone-induced colitis as well as to evaluate its cardiovascular adverse effects, paying particular attention to the onset of hypotension, one of the main adverse effects associated with the systemic pharmacological activation of A receptors. Colitis was associated with decreased body weight, an enhanced microscopic damage score and increased levels of colonic myeloperoxidase (MPO). PSB-0777, but not dexamethasone, improved body weight. PSB-0777 and dexamethasone ameliorated microscopic indexes of inflammation and reduced MPO levels. The beneficial effects of PSB-0777 on inflammatory parameters were prevented by the pharmacological blockade of A receptors. No adverse cardiovascular events were observed upon PSB-0777 administration. The novel A receptor agonist PSB-0777 could represent the base for the development of innovative pharmacological entities able to act in an event-specific and site-specific manner. |
| 2018 | The role of Syk/IĸB-α/NF-ĸB pathway activation in the reversal effect of BAY 61-3606, a selective Syk inhibitor, on hypotension and inflammation in a rat model of zymosan-induced non-septic shock. | Clin Exp Pharmacol Physiol | Spleen tyrosine kinase (Syk), a non-receptor tyrosine kinase, plays an important role in allergic diseases and inflammation. Syk triggers several intracellular signalling cascades including Toll-like receptor signalling to activate inflammatory responses following fungal infection but the role of this enzyme in zymosan (ZYM)-induced non-septic shock and its impacts on hypotension and inflammation in rats is not well understood. This study was conducted to determine the effects of Syk inhibition on ZYM-induced alterations in the expression and/or activities of Syk, inhibitor ĸB (IĸB)-α, and nuclear factor-ĸB (NF-ĸB) p65. We also examined the effect of Syk inhibition on inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and tumour necrosis factor (TNF)-α, and activity of myeloperoxidase (MPO) that contribute to hypotension and inflammation. Administration of ZYM (500 mg/kg, ip) to male Wistar rats decreased blood pressure and increased heart rate. These changes were associated with increased expression and/or activities of Syk, NF-κB p65, iNOS and COX-2 and decreased expression of IκB-α with enhanced levels of nitrite, nitrotyrosine, 6-keto-PGF , and TNF-α and activity of MPO in renal, cardiac and vascular tissues. ZYM administration also elevated serum and tissue nitrite levels. The selective Syk inhibitor BAY 61-3606 (3 mg/kg, ip) given 1 hour after ZYM injection reversed all of these changes induced by ZYM. These results suggest that Syk/IĸB-α/NF-ĸB pathway activation contributes to hypotension and inflammation caused by the production of vasodilator and proinflammatory mediators in the zymosan-induced non-septic shock model. |
| 2017 | Elucidating the role of leptin in systemic inflammation: a study targeting physiological leptin levels in rats and their macrophages. | Am J Physiol Regul Integr Comp Physiol | To elucidate the role of leptin in acute systemic inflammation, we investigated how its infusion at low, physiologically relevant doses affects the responses to bacterial lipopolysaccharide (LPS) in rats subjected to 24 h of food deprivation. Leptin was infused subcutaneously (0-20 μg·kg·h) or intracerebroventricularly (0-1 μg·kg·h). Using hypothermia and hypotension as biomarkers of systemic inflammation, we identified the phase extending from 90 to 240 min post-LPS as the most susceptible to modulation by leptin. In this phase, leptin suppressed the rise in plasma TNF-α and accelerated the recoveries from hypothermia and hypotension. Suppression of TNF-α was not accompanied by changes in other cytokines or prostaglandins. Leptin suppressed TNF-α when infused peripherally but not when infused into the brain. Importantly, the leptin dose that suppressed TNF-α corresponded to the lowest dose that limited food consumption; this dose elevated plasma leptin within the physiological range (to 5.9 ng/ml). We then conducted in vitro experiments to investigate whether an action of leptin on macrophages could parallel our in vivo observations. The results revealed that, when sensitized by food deprivation, LPS-stimulated peritoneal macrophages can be inhibited by leptin at concentrations that are lower than those reported to promote cytokine release. It is concluded that physiological levels of leptin do not exert a proinflammatory effect but rather an anti-inflammatory effect involving selective suppression of TNF-α via an action outside the brain. The mechanism of this effect might involve a previously unrecognized, suppressive action of leptin on macrophage subpopulations sensitized by food deprivation, but future studies are warranted. |
| 2017 | Continuous hemoadsorption with a cytokine adsorber during sepsis - a review of the literature. | Int J Artif Organs | Sepsis is a well-recognized healthcare issue worldwide, ultimately resulting in significant mortality, morbidity and resource utilization during and after critical illness. In its most severe form, sepsis causes multi-organ dysfunction that produces a state of critical illness characterized by severe immune dysfunction and catabolism. Sepsis induces the activation of complement factor via 3 pathways and the release of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin-1beta (IL-1β), resulting in a systemic inflammatory response. The inflammatory cytokines and nitric oxide release induced by sepsis decrease systemic vascular resistance, resulting in profound hypotension. The combination of hypotension and microvascular occlusion results in tissue ischemia and ultimately leads to multiple organ failure. Several clinical and experimental studies have reported that treatment using adsorption of cytokines is beneficial during endotoxemia and sepsis. This review article analyzes the efficacy of CytoSorb® adsorber in reducing the inflammatory response during sepsis. The CytoSorb® adsorber is known to have excellent adsorption rates for inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, and TNF-α. Studies have demonstrated that treatment with cytokine adsorbing columns has beneficial effects on the survival rate and inflammatory responses in animal septic models. Additionally, several cases have been reported in which treatment with cytokine adsorbing columns is very effective in hemodynamic stabilization and in preventing organ failure in critically ill patients. Although further investigations and clinical trials are needed, treatment with cytokine adsorbing columns may play an important role in the treatment of sepsis in the near future. |
| 2017 | Sodium azide suppresses LPS-induced expression MCP-1 through regulating IκBζ and STAT1 activities in macrophages. | Cell Immunol | Sodium azide (NaN) is a chemical compound with multiple toxic effects on vascular and neuronal systems, causing hypotension and neurotoxicity, respectively. In order to test its effects on the immune system, human and mouse macrophage-like cell lines were treated with nontoxic doses of NaN and the changes in LPS-induced inflammatory activation was measured. Interestingly, the LPS-induced expression of monocyte chemoattractant protein (MCP)-1 was suppressed by NaN without affecting the expression of IL-8 and TNF-α. Further analysis of cellular signaling mediators involved in the expression of these cytokines revealed that NaN suppressed the LPS-induced activation of signal transducers and activator of transcription (STAT)1 and inhibitor of κB (IκB) ς, which are involved in the LPS-induced expression of MCP-1, while the LPS-induced activation of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) was not affected. The LPS-induced expression of MCP-2 and CXCL10, which are also regulated by STAT1, was suppressed by NaN. Similarly, the LPS-induced expression of IL-6, which is regulated by IκBζ, was suppressed by NaN. These results demonstrate that NaN selectively suppresses the LPS-induced expression of pro-inflammatory mediators through the suppression of STAT1 and IκBζ activation. These new findings about the activity of NaN may contribute to the development of specific regulators of macrophage activity during acute and chronic inflammation. |
| 2017 | Activation of mTOR/IκB-α/NF-κB pathway contributes to LPS-induced hypotension and inflammation in rats. | Eur J Pharmacol | Mammalian target of rapamycin (mTOR), a serine/threonine kinase plays an important role in various pathophysiological processes including cancer, metabolic diseases, and inflammation. Although mTOR participates in Toll-like receptor 4 signalling in different cell types, the role of this enzyme in sepsis pathogenesis and its effects on hypotension and inflammation in endotoxemic rats remains unclear. In this study we investigated the effects of mTOR inhibition on lipopolysaccharide (LPS)-induced changes on expressions and/or activities of ribosomal protein S6 (rpS6), an mTOR substrate, nuclear factor-κB (NF-κB) p65, inhibitor κB (IκB)-α, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 with production of nitric oxide, peroxynitrite, prostacyclin, and tumor necrosis factor (TNF)-α and activity of myeloperoxidase (MPO), which results in hypotension and inflammation. Injection of LPS (10mg/kg, i.p.) to male Wistar rats decreased blood pressure and increased heart rate that were associated with elevated nitrotyrosine, 6-keto-PGF, and TNF-α levels and MPO activity, and increased expressions and/or activities of rpS6, NF-κB p65, iNOS, and COX-2 and decreased expression of IκB-α in renal, cardiac, and vascular tissues. LPS also increased serum and tissue nitrite levels. Rapamycin (1mg/kg, i.p.) given one h after injection of LPS reversed these effects of LPS. These data suggest that the activation of mTOR/IκB-α/NF-κB pathway associated with vasodilator and proinflammatory mediator formation contributes to LPS-induced hypotension and inflammation. |
| 2016 | Successful therapy of Clostridium difficile infection with fecal microbiota transplantation. | J Physiol Pharmacol | Clostridium difficile infection (CDI) is the most common cause of infectious diarrhea and represents an important burden for healthcare worldwide. Symptoms of severe CDI include watery, foul-smelling diarrhea, peripheral leucocytosis, increased C-reactive protein (CRP), acute renal failure, hypotension and pseudomembranous colitis. Recent studies indicate that the main cause of CDI is dysbiosis, an imbalance in the normal gut microbiota. The restoration of a healthy gut microbiota composition via fecal microbiota transplantation (FMT) recently became more popular. The aim of the present study was to assess the effect of FMT on the healing of CDI and to analyze the changes in the level of pro-inflammatory markers (C-reactive protein, fecal calprotectin) and pro-inflammatory cytokines. Eighteen patients with CDI were included in our study (6 males and 12 females) with recurrent and/or severe CDI. The FMT was performed in 17 patients using colonoscopy, including 16 patients receiving a one-time FMT and 1 patient who needed 2 additional FMTs. One patient was treated with a single round of FMT using push-and-pull enteroscopy. In all CDI patients, before and 3 weeks after FMT, the following parameters were analyzed: C-reactive protein, fecal calprotectin, and plasma interleukin (IL)-6, IL-8 and IL-12, and tumor necrosis factor-alpha (TNF-α). In addition, the plasma level of LL-37, a cathelicidine peptide was assessed by fluorescence-activated cell sorting (FACS) before and 3 months after FMT. Finally, in 7 patients a microbiome analysis was performed by sequencing of 16SrRNA in stool probes obtained before and 3 weeks after FMT. The healing rate of CDI was 94%. In all successfully treated patients no recurrent CDI was observed during follow-up (16 months). The serum level of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8 and IL-12) significantly decreased after FMT. Similarly, CRP and fecal calprotectin normalized after FMT. 3 months after FMT a significant increase of LL-37 in the plasma of successfully treated patients was monitored. The sequencing analysis demonstrated an elevated abundance of beneficial bacterial species such as Lactobacillaceae, Ruminococcaceae, Desulfovibrionaceae, Sutterellaceae and Porphyromonodacea after FMT. No serious side effects were observed. We concluded that FMT represented a very effective and safe treatment of recurrent and/or severe CDI and led to favorable shifts in the composition of gut microbiome. |
| 2017 | The Jarisch-Herxheimer Reaction After Antibiotic Treatment of Spirochetal Infections: A Review of Recent Cases and Our Understanding of Pathogenesis. | Am J Trop Med Hyg | Within 24 hours after antibiotic treatment of the spirochetal infections syphilis, Lyme disease, leptospirosis, and relapsing fever (RF), patients experience shaking chills, a rise in temperature, and intensification of skin rashes known as the Jarisch-Herxheimer reaction (JHR) with symptoms resolving a few hours later. Case reports indicate that the JHR can also include uterine contractions in pregnancy, worsening liver and renal function, acute respiratory distress syndrome, myocardial injury, hypotension, meningitis, alterations in consciousness, seizures, and strokes. Experimental evidence indicates it is caused by nonendotoxin pyrogen and spirochetal lipoproteins. Mediation of the JHR in RF by the pro-inflammatory cytokines tumor necrosis factor (TNF), interleukin (IL)-6, and IL-8 has been proposed, consistent with measurements in patients' blood and inhibition by anti-TNF antibodies. Accelerated phagocytosis of spirochetes by polymorphonuclear (PMN) leukocytes before rise in cytokines is responsible for removal of organisms from the blood, suggesting an early inflammatory signal from PMNs. Rarely fatal, except in neonates and in pregnancy for African women whose babies showed high perinatal mortality because of low birth weight, the JHR can be regarded as an adverse effect of antibiotics, necessary for achieving a cure of spirochetal infections. |
| 2017 | Staphylococcus aureus Bacteremia in Patients not Meeting Sepsis Criteria: Clinical Features, Host Immune Response and Outcomes. | J Clin Med Ther | Limitations regarding the sensitivity and specificity of the systemic inflammatory response (SIRS) criteria prompted the recent revision in consensus definitions of sepsis and septic shock. We evaluated patients with bacteremia (SAB) who did not meet SIRS criteria for sepsis (SIRS-negative, SIRS-N) to compare host immune response and outcomes with SIRS-positive (P) patients.A prospective observational study of patients hospitalized for SAB during 2012-2015 was conducted. Pro- (TNFα, IL6, IL8) and anti-inflammatory (IL10) cytokine levels (pg/mL) were compared between SIRS-N and SIRS-P patients. Outcome endpoints were day 4 persistence and 30-day mortality.Of the 353 study patients, 23% were SIRS-N. A similar proportion of SIRS-N and SIRS-P patients had an infection-related admitting diagnosis (70% . 66%, p=0.5946), and both groups received timely antibiotic administration. Less than 1/3 of SIRS-N group had abnormal WBC count, tachycardia, or tachypnea while <15% had fever/hypothermia or hypotension. Initial proand anti-inflammatory cytokine levels were significantly lower and in balance as indicated by IL10/TNF ratio in SIRS-N compared to SIRS-P patients. IL10/TNF ratio increased progressively in patients with increasing sepsis severity and mortality.Clinical management of patients with SAB seemed driven largely by clinician assessment rather than SIRS criteria alone, with one in 4 patients not meeting SIRS criteria. Importantly, the severity of presentation and outcomes of SAB correspond well to the magnitude of underlying imbalance in pro- and anti-inflammatory cytokine levels, supporting the updated sepsis definition as "life-threatening organ dysfunction caused by a dysregulated host response to infection".In a prospective observational study of 353 patients with bacteremia, 23% did not meet SIRS criteria for sepsis. Severity of sepsis and risk of death is supported by a dysregulated host cytokine response with progressively increasing IL10/TNF ratio. |
| 2016 | Online Haemodiafiltration Improves Inflammatory State in Dialysis Patients: A Longitudinal Study. | PLoS One | Patients undergoing conventional hemodialysis (C-HD) present a greater immuno-inflammatory state probably related to uremia, sympathetic nervous system (SNS) activation and /or membrane bioincompatibility, which could improve with a technique-switching to online hemodiafiltration (OL-HD). The antigen-independent pathway activation of this modified immunologic state turns dendritic cells (DC) into an accurate cell model to study these patients. The aim of this study is to further evaluate the immune-inflammatory state of patients in C-HD assessed by DC maturation.31 patients were submitted to C-HD and after 4 months switched to the OL-HD technique. Monocytes-derived DCs from HD patients were cultured in the presence of IL-4/GM-CSF. DC-maturation was evaluated by assessing the maturation phenotype by flow cytometry (FACs). DCs-functional capacity to elicit T-cell alloresponse was studied by mixed leucocyte reaction. Cytokine release was assessed by FACs and SNS was evaluated measuring renalase levels by ELISA.An up-regulation of maturation markers was observed in C-HD DCs which induced two fold more T cells proliferation than OL-HD DCs. Also, C-HD-mDCs presented with over-production of pro-inflammatory cytokines (IL-6, IL-1β, IL-8, IL-10 and TNF-α) compared with OL-HD-mDC (P<0·05). Results were correlated with clinical data. When SNS was evaluated, hypotension events and blood pressure were significantly lower and renalase levels were significantly higher after conversion to OL-HD. Diabetes mellitus type 2 patients also found beneficial reduction of mDC when converted to OL-HD compared to non-diabetics.OL-HD could interfere with immuno-inflammatory state in HD patients with an improvement of renalase levels as potential key mediators in the mechanistic pathway of down-regulation of DC maturation. |
| 2016 | Sepsis modeling in mice: ligation length is a major severity factor in cecal ligation and puncture. | Intensive Care Med Exp | The cecal ligation and puncture (CLP) model, a gold standard in sepsis research, is associated with an important variability in mortality. While the number of punctures and needle size is well described in CLP animal studies, the length of cecal ligation is often not. The relationship between cecal ligation and survival in mice is briefly reported in the literature; therefore, we devised an investigation in mice of the consequences of three standardized cecal ligation lengths on mortality and the severity of the ensued sepsis.Male C57BL/6J mice underwent standardized CLP. The cecum was ligated at 5, 20, or 100 % of its total length and further perforated by a single 20-G puncture. Mortality was analyzed. We assessed blood lactate, serum creatinine levels, and serum cytokines (TNF-α, IL-1β, IL-6, and IL-10) after procedure in a control group and in ligated mice.Mortality was directly related to ligation length: median survival was 24 h for the "100 %" group and 44 h for the "20 %" group. Blood lactate increased proportionally with the ligation length. At 6 h post-procedure, pro-inflammatory cytokines significantly increased in the ligated group with significantly higher serum levels of IL-6 in the 100 % group compared to the other ligated groups. The 20 % group exhibited the characteristics of septic shock with hypotension below 65 mmHg, pro-inflammatory balance, organ dysfunction, and hyperlactatemia.Cecal ligation length appears to be a major limiting factor in the mouse CLP model. Thus, this experimental model should be performed with high consistency in future protocol designs. |
| 2016 | 17-DMAG, an HSP90 Inhibitor, Ameliorates Multiple Organ Dysfunction Syndrome via Induction of HSP70 in Endotoxemic Rats. | PLoS One | Sepsis is a systemic inflammatory disorder, accompanied with elevated oxidative stress, leading to multiple organ dysfunction syndrome (MODS), and disseminated intravascular coagulation. 17-Dimethylaminoethylamino- 17-demethoxygeldanamycin (17-DMAG), a heat shock protein (HSP) 90 inhibitor, has been reported to possess anti-inflammatory effects. In this study, the beneficial effects of 17-DMAG on lipopolysaccharide (LPS) induced MODS and DIC was evaluated in anesthetized rats. 17-DMAG (5 mg/kg, i.p.) was significantly increased survival rate, and prevented hypotension in LPS (30 mg/kg i.v. infused for 4 h) induced endotoxemia. The elevated levels of alanine aminotransferase (ALT), creatine phosphokinase (CPK), lactate dehydrogenase, creatinine, nitric oxide (NO) metabolites, IL-6, and TNF-α in LPS-exposed rat plasma were significantly reduced by 17-DMAG. Moreover, 17-DMAG suppressed LPS-induced superoxide anion production and caspase 3 activation in heart tissues. LPS induced the prolongation of prothrombin time, and a pronounced decrease in platelet count, which were improved by 17-DMAG. 17-DMAG markedly induced HSP70 and heme oxygenase (HO)-1, and suppressed inducible nitric oxide synthase (iNOS) and phosphorylated NF-κB p65 protein expression in organs 6 h after LPS initiation. Pretreatment with high dose of quercetin (300 mg/kg, i.p.), as an HSP70 inhibitor, reversed the beneficial effects of 17-DMAG on survival rate, plasma levels of ALT, CPK, creatinine, IL-6, and NO metabolites, iNOS induction, and caspase-3 activation in LPS-treated rats. In conclusion, 17-DMAG possesses the anti-inflammatory and antioxidant effects that were proved through LPS-induced acute inflammation, which is associated with induction of HSP70 and HO-1, leading to prevent MODS in sepsis. |
| 2016 | Modulation by Central MAPKs/PI3K/sGc of the TNF-α/iNOS-dependent Hypotension and Compromised Cardiac Autonomic Control in Endotoxic Rats. | J Cardiovasc Pharmacol | Reduced blood pressure (BP) and cardiac autonomic activity are early manifestations of endotoxemia. We investigated whether these effects are modulated by central mitogen-activated protein kinases (MAPKs) and related phosphoinositide-3-kinase (PI3K)/soluble guanylate cyclase (sGC) signaling in conscious rats. The effect of pharmacologic inhibition of these molecular substrates on BP, heart rate (HR), and heart rate variability (HRV) responses evoked by intravascular lipopolysaccharide (LPS) (10 mg/kg) were assessed. LPS (1) lowered BP (2) increased HR, (3) reduced time [SD of beat-to-beat intervals (SDNN), and root mean square of successive differences in R-R intervals (rMSSD)], and frequency domain indices of HRV (total power and spectral bands of low and high-frequency), and (4) elevated serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels. The inhibition of TNF-α (pentoxifylline) or inducible nitric oxide synthase (iNOS, aminoguanidine) abolished hemodynamic, HRV, and inflammatory actions of LPS. Intracisternal (i.c.) injection of ODQ (sGC inhibitor), wortmannin (PI3K inhibitor), and SP600125 (MAPKJNK inhibitor) mitigated the hypotensive and tachycardic actions of LPS but failed to affect associated decreases in HRV. MAPKp38 inhibition by i.c. SB203580 produced exactly opposite effects. None of the LPS effects was altered after i.c. PD98059 (MAPKERK1/2 inhibitor). Overall, central MAPKs/PI3K/sGC pathways variably contribute to the TNF-α/iNOS-dependent reductions in BP and HRV seen during endotoxic shock. |
| 2016 | Deep anesthesia worsens outcome of rats with inflammatory responses. | Inflamm Res | We tested the hypothesis that deep anesthesia with sevoflurane, known as a potent immunomodulator, for 4 h would worsen the 24-h outcomes of rats through modulation of the inflammatory responses.Forty-nine male Wistar rats, administered low dose of lipopolysaccharide (0.5 mg/kg) intravenously to elicit moderate inflammatory responses mimicked mild surgical stress, underwent one minimum alveolar concentration (MAC) or 2 MAC sevoflurane anesthesia for 4 h. The 24-h survival rate, arterial blood gases, plasma interleukin (IL)-6 and tumor necrosis factor (TNF)-α concentrations, and rate of T lymphocyte apoptosis in spleen were evaluated. We further examined the effects of hypotension and TNF-α discharge on the survival rate.The survival rate in 2 MAC group was significantly lower accompanied with decreased base excess and increased level of cytokines (IL-6, TNF-α) compared to 1 MAC group. The apoptosis rate did not differ between the two groups. Neither norepinephrine infusion to restore hypotension nor administration of anti-TNF-α antibody improved the outcome in the 2 MAC group.Deep anesthesia with sevoflurane even for a short-term period augments the release of inflammatory cytokines evoked by inflammatory insults like surgical stress, impairs the acid-base balance, and subsequently deteriorates the outcomes. |
| 2016 | Dexmedetomidine Combined with General Anesthesia Provides Similar Intraoperative Stress Response Reduction When Compared with a Combined General and Epidural Anesthetic Technique. | Anesth Analg | Epidural anesthesia may attenuate the sympathetic hyperactivity and stress response from surgery. In this study, we compared the stress response, hemodynamic variables, and recovery profiles of patients undergoing total IV anesthesia (TIVA) and intraoperative dexmedetomidine with those receiving epidural anesthesia and TIVA.Ninety patients undergoing elective open gastrectomy under TIVA were recruited. The dexmedetomidine group (group D, n = 30) received IV dexmedetomidine 0.6 μg/kg before the induction of general anesthesia, followed by dexmedetomidine 0.4 μg/kg/h until peritoneal closure. The control group (group C, n = 30) received volume-matched normal saline infusion as placebo. The epidural group (group E, n = 30) received epidural anesthesia with 0.375% ropivacaine combined with TIVA. The hemodynamic variables and recovery characteristics during emergence were evaluated. Blood samples for norepinephrine (NE), epinephrine (E), cortisol (Cor), and cytokines (tumor necrosis factor-α [TNF-α], interleukin [IL]-6, and IL-10) were obtained before the administration of dexmedetomidine or epidural anesthesia (baseline), immediately after tracheal intubation, upon incision, at the time of celiac exploration, and at tracheal extubation.Compared with group E, there were no differences in the plasma concentration levels of NE, E, Cor, and cytokines (TNF-α, IL-6, and IL-10) in group D at all time points. The levels of NE and E in groups D and E were significantly lower than that in group C, at all time points following induction (all P < 0.0001 except at incision which were P = 0.001 and P = 0.004), and the level of Cor in groups D and E was significantly lower than that in group C at celiac exploration (P = 0.017 and P = 0.019) and immediately after tracheal extubation (P < 0.0001). The levels of TNF-α, IL-6, and IL-10 increased after the celiac exploration in the 3 groups. The levels of plasma TNF-α, IL-6, and IL-6/IL-10 ratio were higher in group C than in groups D and E at celiac exploration and tracheal extubation (all P < 0.0001 except at celiac exploration which were P = 0.005 and P =0.038 for TNF-α and P = 0.049 and P = 0.038 for IL-6/IL-10 ratio). In group D, the heart rate was significantly slower after commencing dexmedetomidine and remained significantly slower throughout the operative course (all P < 0.0001 except at tracheal extubation which was P = 0.032). The number of patients who required intervention because of intraoperative hypotension was significantly higher in group E (36.7%) compared with groups D and C (13.3% and 10.0%) (P = 0.037, P = 0.015). The times to eye opening and tracheal extubation were similar in all groups. There were fewer incidences of agitation in group D (6.7 %) than in group C (26.6%) (P = 0.038).When used in conjunction with TIVA, intraoperative dexmedetomidine blunts surgical stress responses to an extent comparable to combined epidural and general anesthesia without compromising hemodynamic stability and with minimal adverse effects during the intraoperative period. |
| 2016 | If Channel Inhibition With Ivabradine Does Not Improve Cardiac and Vascular Function in Experimental Septic Shock. | Shock | Previous studies have suggested that lowering heart rate (HR) by selective β1-blockers improves sepsis-induced cardiac and vascular dysfunction primarily by decreasing proinflammatory pathways. However, the impact of isolated heart rate reduction (HRR) on hemodynamics and inflammatory pathways remains unknown. The present study was designed to assess the effects of HRR by ivabradine, an If channel inhibitor, on cardiovascular function and inflammatory pathways in peritonitis-induced septic shock in rats.Randomized animal study.University research laboratory.Four hours after cecal ligation and puncture (CLP), Wistar rats were randomly allocated to the following groups: CLP (n = 8) and CLP + ivabradine (n = 8, administered per os 4 h after the surgery). Another eight Wistar male rats underwent sham operation. All rats received a continuous infusion of saline (10 mL kg h), analgesic (nalbuphine: 0.2 mg kg h), and antibiotics (imipenem and cilastatin sodium: 10 mg kg) 4 h after the surgery. Assessment at 18 h included hemodynamics, in vivo cardiac function by echocardiography, and ex vivo vasoreactivity by myography. Circulating cytokine levels (TNF-α, IL-6, and IL-10) were measured by ELISA, whereas cardiac and vascular protein expressions of NF-κB/IκBα/iNOS and Akt/eNOS were assessed by Western blotting.Compared with sham animals, CLP induced tachycardia, hypotension, decreased cardiac output, hyperlactatemia, and vascular hyporesponsiveness to vasopressors. Compared with the CLP group, adjunction of ivabradine decreased the HR without any impact on blood pressure, lactatemia, or vascular responsiveness to vasopressors. Adjunction of ivabradine to CLP rats had no impact on TNF-α, IL-6, and IL-10 cytokines, or on the protein expression levels of phosphorylated forms of NF-κB, Akt, eNOS, and degradation of IκBα in cardiac and vascular tissues.Isolated HRR by ivabradine in an experimental model of septic shock does not appear to be associated with any effect on the tested parameters of cardiac function or on vascular responsiveness to vasopressors. Moreover, in this setting, ivabradine does not alter the circulating levels of selected pro/anti-inflammatory cytokines or cardiac and vascular NF-κB/IκBα protein expression levels. |
| 2016 | Puerarin attenuates the inflammatory response and apoptosis in LPS-stimulated cardiomyocytes. | Exp Ther Med | Patients with septic shock suffer from high mortality rates, particularly when complicated by severe myocardial depression which is characterized by hypotension and a reduction in cardiac output. Inflammation is an important factor involved in the early stages of sepsis. The aim of the present study was to investigate the effect of the Chinese herbal compound puerarin (1, 5, 10, 20 and 40 µM) on cardiomyocyte inflammatory response in a sepsis model using H9c2 cardiomyocytes stimulated with 1 µg/ml lipopolysaccharide (LPS). The mRNA expression levels of tumor necrosis factor (TNF)-α and interleukin (IL)-β were evaluated using reverse transcription-quantitative polymerase chain reaction. In addition, the protein expression levels of various factors were determined using western blot analysis. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was used to evaluate the apoptosis rates in the various groups, and immunocytochemical analysis was employed to determine the effect of puerarin on the nuclear translocation of p65 protein. The present study demonstrated that LPS stimulation increased IL-1β and TNF-α mRNA expression levels, as compared with the controls (P<0.05). Following treatment with various concentrations of puerarin, the expression levels of IL-1β and TNF-α were markedly blunted, particularly in the LPS + 40 µM puerarin group (P<0.05 vs. the LPS group). Furthermore, puerarin administration significantly inhibited LPS-induced apoptosis in H9c2 cardiomyocytes, as determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining (TUNEL positive cells: LPS + 40 µM puerarin group, 5.5% vs. LPS group, 10.5%; P<0.01). In addition, puerarin significantly decreased LPS-induced phosphorylated nuclear factor (p-NF)-κB p65 and Bax expression levels, and increased the expression levels of Bcl-2, as compared with the LPS group (P<0.05). These data indicated that puerarin may serve as a valuable protective agent against cardiovascular inflammatory diseases. |
| 2015 | Sesamol ameliorates hypotension by modulating cytokines and PPAR-gamma in systemic inflammatory response. | EXCLI J | Sepsis is one of the major causes of death reported in intensive care units. Acute kidney injury (AKI) and hypotension are important in the pathogenesis and mortality of systemic inflammatory response (SIR). Sesamol delays mortality in sepsis; however, its effects on AKI and hypotension and the role of peroxisome proliferator-activated receptor-ɣ (PPAR-γ) activation have not been established. We investigated the effect of sesamol on SIR in cecal ligation and puncture (CLP)-induced acute kidney injury and lipopolysaccharide (LPS)-induced hypotension in rats. Sesamol was subcutaneously injected 1 h after SIR. Renal function (BUN and CRE) and proinflammatory mediators interleukin (IL)-1β and IL-6 were increased after CLP. Tumor necrosis factor (TNF)-α, IL-1β, IL-10, and nitrite production were significantly increased 6 h after LPS-induced hypotension (mean arterial pressure was significantly decreased). Sesamol significantly inhibited BUN, CRE, IL-1β, IL-6, and nitrite after CLP-induced acute renal injury. In addition, sesamol increased mean arterial pressure and IL-10, inhibited TNF-α and IL-1β, but did not affect nitrite production in LPS-induced hypotension. Sesamol increased PPAR-γ in the leucocytes and peritoneal macrophages in LPS-induced SIR. We conclude that sesamol regulates leucocyte and macrophage PPAR-γ-associated systemic cytokines expression, thereby ameliorates acute kidney injury and hypotension in rats. |
| 2015 | [Protection of Electro-acupuncture for Gastric Mucosa of Patients Undergoing Endoscopic Sinus Surgery]. | Zhongguo Zhong Xi Yi Jie He Za Zhi | To evaluate the effect of electro-acupuncture (EA) on gastric mucosal oxygenation and systemic inflammatory response in patients undergoing endoscopic sinus surgery with controlled hypotension (CH), and to explore its protective effect on gastric mucosa.Fifty-four patients, 18-65 years old, grade I-II of American Society of Anesthesiology (ASA), who were scheduled for endoscopic sinus surgery were randomly assigned to two groups, group A (general anesthesia group) and group B (general anesthesia combined EA anesthesia group), 27 in each group. Conrolled hypotension was executed during operation, and mean arterial pressure (MAP) was maintained at 55-65 mmHg. After tracheal intubation gastric tesiometer catheter was indwelled through nasal cavity or oral cavity. After successful indwelling, it was connected with gastric mucosa monitoring mode of multifunctional parameters monitor. Patients' MAP and heart rate (HR), pHi, partial pressure of carbon dioxide (PgCO2), arterial partial pressure of carbon dioxide (Pg-aCO2) and endtidal pressure of carbon dioxide (Pg-etCO2) were measured and recorded at T, (immediately before induced hypotension), T, (20 min following induced hypotension to target MAP), T2 (40 min following induced hypotension to target MAP), T3 (20 min after ending induced hypotension), and T4(40 min after ending induced hypotension). Blood samples were intravenously collected, TNF-alpha, IL-1, and IL-6 were detected by ELISA 24 h before operation, during operation (T3), and 24 h after operation.After hypotension was induced, Pg-CO2, Pg-aCO2 and Pg-etCO2 increased significantly (P < 0.01, P < 0.05), while pHi decreased significantly (P < 0.01) in both groups at T1-T4 than those at T0. During T1-T4, PgCO2, Pg-aCO2, and Pg-etCO2 were higher (P < 0.01, P < 0.05), while pHi was lower in group A than in group B (P < 0.01). Furthermore, TNF-alpha, IL-1, and IL-6 increased significantly in both groups during operation and 24 h after operation, when compared with those 24 h before operation (P < 0.01, P < 0.05). TNF-alpha and IL-1 in group A were higher than those in group B (P < 0.05) during operation and 24 h after operation, but with no significant difference in the plasma concentration of IL-6 (P > 0.05).EA exerted obvious protective effect of gastric mucosal injury in endoscopic sinus surgery with controlled hypotension, which might be achieved by increasing gastric mucosal blood flow, maintaining oxygen supply and demand, inhibiting inflammatory response, and alleviating injury of gastric mucosal barrier. |
| 2016 | Inhibition of complement C3 might rescue vascular hyporeactivity in a conscious hemorrhagic shock rat model. | Microvasc Res | Vascular hyporeactivity in severe hemorrhagic shock could induce refractory hypotension and is an important cause of death. The global acute inflammatory response induced in shock triggers the over-expression of reactive oxygen species, NO, ET1 and TNF-α, which play essential roles in the pathology of vascular hyporeactivity. This leads to a hypothesis that inhibition of the complement system, the mediator of the inflammatory cascade, might be a promising therapeutic exploration for vascular hyporeactivity.We use cobra venom factor (CVF) and the soluble form of CR1 (sCR1) which deplete or inhibit complement C3 respectively to examine its role in vascular hyporeactivity in a conscious hemorrhagic shock rat model.We first confirmed the over-activation of C3 during shock and the down-regulation effects of CVF and sCR1 on C3. Then, both CVF and sCR1 could significantly mitigate the over-expression of serum NO, ET-1, TNF-α and reactive oxygen species. Finally, the vascular reactivity of superior mesenteric arteries (SMA) was examined in vitro, which confirmed the massive reduction of vascular reactivity in shock, which was significantly rescued by both CVF and sCR1.Inhibition of C3 might improve the reactivity of SMA to norepinephrine during hemorrhagic shock possibly through the downregulation of NO, ET1, TNF-α and reactive oxygen radicals. |
| 2016 | Central GABAA receptors are involved in inflammatory and cardiovascular consequences of endotoxemia in conscious rats. | Naunyn Schmiedebergs Arch Pharmacol | γ-Aminobutyric acid (GABA), the principal brain inhibitory neurotransmitter, modulates inflammatory and neurodegenerative disease. Here, we tested the hypothesis that central GABAergic neurotransmission mediates the detrimental inflammatory, hemodynamic, and cardiac autonomic actions of endotoxemia. The effects of drugs that block GABA receptors or interfere with GABA uptake or degradation on blood pressure (BP), heart rate (HR), and HR variability (HRV) responses elicited by i.v. lipopolysaccharide (LPS) were assessed in conscious rats. The hypotensive effect of LPS (10 mg/kg) was blunted after intracisternal (i.c.) administration of bicuculline (GABAA receptor antagonist) or saclofen (GABAB receptor antagonist). By contrast, the concomitant LPS-evoked tachycardia and decreases in time domain and frequency domain indices of HRV (measures of cardiac autonomic control) were abolished upon treatment with bicuculline but not saclofen. Increases in serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) caused by LPS disappeared in the presence of bicuculline or saclofen, whereas LPS-evoked increases in serum nitric oxide metabolites (NOx) were counteracted by bicuculline only. None of the endotoxemia effects was altered in rats treated with i.c. tiagabine (GABA reuptake inhibitor) or vigabatrin (GABA transaminase inhibitor). These data suggest a major role for central GABAA receptors in the inflammatory and cardiovascular effects of endotoxemia. |
| 2016 | Vitamin C Attenuates Hemorrhagic Hypotension Induced Epithelial-Dendritic Cell Transformation in Rat Intestines by Maintaining GSK-3β Activity and E-Cadherin Expression. | Shock | To investigate the roles of epithelial-dendritic cell transformation (EDT) characterized by the expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) in the occurrence of tissue inflammation induced by hemorrhagic hypotension (HH), the protective effect of vitamin C (VitC), and the potential mechanisms.We conducted an in vitro study using the rat intestinal epithelial cells (IEC-6). After hypoxic culture with or without VitC for 2, 6, 24, and 48 h (n = 3 per group), the expression levels of DC-SIGN, E-cadherin, and Glycogen synthase kinase-3β-S9 (GSK-3β-S9) in IEC-6 cells, IL-1β, and IL-6 concentrations in the cell culture medium were measured. To investigate the potential mechanism, we inhibited E-cadherin expression by siRNA and GSK-3β activity by TDZD-8, respectively. The in vivo study was conducted by establishing SD rat HH model. We observed the expression levels and location of DC-SIGN in the intestines. We also showed histological damage, TNF-α and IL-6 concentrations, and organ injury scores at 2, 6, and 24 h after HH (n = 6 per group), with or without VitC pretreatment.Hypoxia-induced DC-SIGN expression in IEC-6 cells in a time-dependent manner and the inflammatory factors were also increased. VitC inhibited all these phenomena. Hypoxia inhibited GSK-3β activity and E-cadherin expression. VitC could ease these inhibitions. The inhibitory effect of VitC on DC-SIGN was diminished when E-cadherin expression was inhibited in advance. TDZD-8 diminished the protective effect of VitC on E-cadherin and abolished inhibitory effect of VitC on DC-SIGN expression. HH-induced DC-SIGN expression in rat intestine epithelial cells and the histological damage scores and pro-inflammatory cytokine levels were also increased.HH induces EDT in rat intestine epithelial cells. VitC maintains GSK-3β activity, attenuates the suppression of E-cadherin caused by hypoxia, and ultimately decreases DC-SIGN expression. |
| 2015 | Cardiovascular and pharmacological implications of haem-deficient NO-unresponsive soluble guanylate cyclase knock-in mice. | Nat Commun | Oxidative stress, a central mediator of cardiovascular disease, results in loss of the prosthetic haem group of soluble guanylate cyclase (sGC), preventing its activation by nitric oxide (NO). Here we introduce Apo-sGC mice expressing haem-free sGC. Apo-sGC mice are viable and develop hypertension. The haemodynamic effects of NO are abolished, but those of the sGC activator cinaciguat are enhanced in apo-sGC mice, suggesting that the effects of NO on smooth muscle relaxation, blood pressure regulation and inhibition of platelet aggregation require sGC activation by NO. Tumour necrosis factor (TNF)-induced hypotension and mortality are preserved in apo-sGC mice, indicating that pathways other than sGC signalling mediate the cardiovascular collapse in shock. Apo-sGC mice allow for differentiation between sGC-dependent and -independent NO effects and between haem-dependent and -independent sGC effects. Apo-sGC mice represent a unique experimental platform to study the in vivo consequences of sGC oxidation and the therapeutic potential of sGC activators. |
| 2015 | Hydrogen sulfide in posthemorrhagic shock mesenteric lymph drainage alleviates kidney injury in rats. | Braz J Med Biol Res | Posthemorrhagic shock mesenteric lymph (PHSML) is a key factor in multiple organ injury following hemorrhagic shock. We investigated the role of hydrogen sulfide (H2S) in PHSML drainage in alleviating acute kidney injury (AKI) by administering D,L-propargylglycine (PPG) and sodium hydrosulfide hydrate (NaHS) to 12 specific pathogen-free male Wistar rats with PHSML drainage. A hemorrhagic shock model was established in 4 experimental groups: shock, shock+drainage, shock+drainage+PPG (45 mg/kg, 0.5 h prehemorrhage), and shock+drainage+NaHS (28 µmol/kg, 0.5 h prehemorrhage). Fluid resuscitation was performed after 1 h of hypotension, and PHMSL was drained in the last three groups for 3 h after resuscitation. Renal function and histomorphology were assessed along with levels of H2S, cystathionine-γ-lyase (CSE), Toll-like receptor 4 (TLR4), interleukin (IL)-10, IL-12, and tumor necrosis factor (TNF)-α in renal tissue. Hemorrhagic shock induced AKI with increased urea and creatinine levels in plasma and higher H2S, CSE, TLR4, IL-10, IL-12, and TNF-α levels in renal tissue. PHSML drainage significantly reduced urea, creatinine, H2S, CSE, and TNF-α but not TLR4, IL-10, or IL-12. PPG decreased creatinine, H2S, IL-10, and TNF-α levels, but this effect was reversed by NaHS administration. In conclusion, PHSML drainage alleviated AKI following hemorrhagic shock by preventing increases in H2S and H2S-mediated inflammation. |
| 2015 | Impaired NO-mediated vasodilatation in rat coronary arteries after asphyxial cardiac arrest. | Acta Anaesthesiol Scand | Cardiovascular dysfunction after cardiac arrest is a common finding. It is unknown whether altered endothelium-mediated vasoreactivity contributes to this dysfunction. We hypothesised that cardiac arrest and resuscitation results in impaired endothelial function. This was addressed by measurements of inflammatory and endothelial plasma markers and of endothelium-dependent vasodilatation in coronary and mesenteric arteries in rats after cardiac arrest and resuscitation.Male Sprague Dawley rats underwent either asphyxia-induced cardiac arrest for 5 min and subsequent resuscitation (n = 30) or a sham procedure (control animals, n = 39). Animals were euthanised after 30 min or 2 h. Blood was analysed for TNF-α, IL-1β, IL-6, IL-10, sE-selectin, sP-selectin, sVCAM-1, ICAM-1, VEGF-α and vWF. Arterial rings of the left anterior descending coronary artery and mesenteric resistance arteries were mounted in microvascular myographs, and concentration-response curves were constructed.The plasma levels of the endothelial markers, sP-selectin and vWF increased following cardiac arrest at both 30 min and 2 h. Acetylcholine-induced endothelium-dependent and mainly nitric oxide (NO)-mediated vasodilatation was impaired in the coronary arteries at 30 min, but not 2 h after resuscitation. Endothelium-derived hyperpolarisation (EDH)-type vasodilatation induced by NS309 and vasodilatation induced by the NO donor sodium nitroprusside was unaltered. In parallel with systemic hypotension, mesenteric arteries exhibited a larger response to NS309 2 h after resuscitation.The present results show marked endothelial alterations after cardiac arrest and resuscitation reflected by increased endothelial plasma markers, impaired NO-mediated coronary vasodilatation in the early post-resuscitation phase and enhanced EDH-type vasodilatation in mesenteric arteries later in the post-resuscitation phase. |
| 2015 | Increased levels of tumor necrosis factor-α involved in rituximab-related acute pulmonary fibrosis in diffuse large B-cell lymphoma. | Am J Clin Pathol | Rituximab is a chimeric anti-CD20 monoclonal antibody with murine variable regions and human IgG1 constant regions that depletes B lymphocytes. It is used with increasing frequency in the treatment of patients with other hematologic malignancies and nonhematologic diseases for its safety and efficacy. Its major adverse effects are infusion related and most commonly consist of fever, chills, dyspnea, and hypotension. Rituximab-induced lung injury, such as interstitial pneumonitis and pulmonary fibrosis, is a rare complication but has been reported.We herein report a patient with diffuse large B-cell non-Hodgkin lymphoma who developed acute pulmonary fibrosis after treatment with rituximab.Simultaneous tumor necrosis factor (TNF)-α levels were significantly increased. The patient had a dramatic recovery that was confirmed by a repeated computed tomography scan, and the levels of TNF-α returned to normal after 2 weeks of methylprednisolone treatment.We observe that increased TNF-α levels may be involved in rituximab-related acute pulmonary fibrosis. |
| 2015 | Sepsis progression to multiple organ dysfunction in carotid chemo/baro-denervated rats treated with lipopolysaccharide. | J Neuroimmunol | Sepsis progresses to multiple organ dysfunction (MOD) due to the uncontrolled release of inflammatory mediators. Carotid chemo/baro-receptors could play a protective role during sepsis. In anesthetized male rats, we measured cardiorespiratory variables and plasma TNF-α, glucocorticoids, epinephrine, and MOD marker levels 90min after lipopolysaccharide (LPS) administration in control (SHAM surgery) and bilateral carotid chemo/baro-denervated (BCN) rats. BCN prior to LPS blunted the tachypneic response and enhanced tachycardia and hypotension. BCN-LPS rats also showed blunted plasma glucocorticoid responses, boosted epinephrine and TNF-α responses, and earlier MOD onset with a lower survival time compared with SHAM-LPS rats. Consequently, the complete absence of carotid chemo/baro-sensory function modified the neural, endocrine and inflammatory responses to sepsis. Thus, carotid chemo/baro-receptors play a protective role in sepsis. |
| 2015 | Celastrol prevents circulatory failure via induction of heme oxygenase-1 and heat shock protein 70 in endotoxemic rats. | J Ethnopharmacol | Celastrol, a quinone methide extracted from the root of Tripterygium wilfordii Hook, possesses anti-oxidant and anti-inflammatory effects. Tripterygium wilfordii Hook is officially listed in the Chinese Pharmacopoeia and is used traditionally against rheumatoid arthritis, ankylosing spondylitis, and cancer. Furthermore, the circulatory protective effect of celastrol on an in vivo animal model of sepsis was investigated.Sepsis is a systemic inflammatory disorder that increases tissue oxidative stress and leads to multiple organ injury. We evaluated the beneficial effects of celastrol on multiple organ failure induced by lipopolysaccharide (LPS) in rats.Celastrol (0.5 and 1.0 mg/kg, i.v.) was administered to anaesthetized rats 2 h before and 30 min after LPS challenge (10 mg/kg, i.v.). Eight hours later, cardiac and aortic protein expressions related to inflammatory responses, superoxide anion production, and reduced glutathione (GSH) level were measured.Treatment with celastrol prevented circulatory failure (bradycardia and hypotension) 8h after LPS challenge. The plasma levels of ALT, LDH, TNF-α, and nitric oxide metabolites increased markedly during sepsis, which significantly reduced after celastrol treatments. Celastrol attenuated iNOS, TNF-α, NF-κB phospho-p65 expression, superoxide anion production, and caspase 3 activity in the cardiovascular system, all of which were markedly elevated after LPS challenge. Furthermore, celastrol induced HO-1 and HSP70 expressions increase in nuclear levels of Nrf2 and HSF-1, respectively, and increase cardiac GSH level 8h after LPS challenge.Anti-inflammatory and anti-oxidant effects of celastrol contribute to prevent circulatory failure in sepsis. Induction of HO-1 and HSP70 by celastrol participates in these beneficial effects. |
| 2015 | Acute intradialytic cardiac function and inflammatory cytokine changes during high-efficiency online hemodiafiltration with acetate-free and standard dialysis solutions. | Ther Apher Dial | Acetate in standard acetate-containing bicarbonate (AC) dialysis fluid could induce peripheral vasodilatation, suppression of myocardial function, and inflammatory cytokine production, resulting in intradialytic hypotension in conventional hemodialysis (HD) patients. Online hemodiafiltration (HDF) provides superior hemodynamic stability over HD. The potentially additive hemodynamic benefits of the novel acetate-free bicarbonate (AF) dialysis fluid in online HDF have never been explored before. The present randomized, double-blind, crossover study was conducted in 22 online HDF patients to investigate the impact of AF dialysis fluid on hemodynamic and cytokine changes compared with AC dialysis fluid in online HDF. The results demonstrated the comparable changes of arterial pressure between AF and AC online HDF. During the study periods, the incidences of composite intradialytic hypotension and other adverse events were not different. The baseline and hourly changes of cardiac index, cardiac output, and peripheral vascular resistance during dialysis were comparable (P=0.534, 0.199, and 0.641, respectively). The percent reductions of NT-proBNP and cTnT were not significantly different (72.6 ± 12.3 vs. 72.6 ± 12.8%, P=0.99 and 35.2 ± 12.8 vs. 36.7 ± 12.0%, P=0.51). The changes of all pro-inflammatory cytokines (IL-2β, IL-6, IL-8, and TNF-α) and anti-inflammatory cytokine (IL-10) during dialysis were comparable between both groups. In conclusion, AF dialysis solution does not offer additional hemodynamic benefit for stable online HDF patients. The hemodynamic stability provided by online HDF might protect the adverse effects of acetate. |
| Comparison of the Effects of Dexmedetomidine vs. Ketamine in Cardiac Ischemia/Reperfusion Injury in Rats - Preliminary Study. | Adv Clin Exp Med | Following ischemia/reperfusion injury, antioxidant defense mechanisms may remain insufficient depending on the duration of ischemia which is caused by any reason (MI, after percutaneous coronary intervention, during cardiac surgery). After that, free oxygen radicals increasing within the cell cause structural deterioration. Cytokines which activate a series of reactions that cause tissue damage and inflammatory response are released during reperfusion of ischemic tissues. In this study, we aimed to compare the effects of dexmedetomidine and ketamine in cardiac ischemia/reperfusion injury.The study included 18 rats randomly divided into three groups. Group I/R (n = 6): control, Group I/R-K (n = 6): ketamine, and Group I/R-D (n = 6): dexmedetomidine. Before the 10 min surgery, after the 20 min ischemia and 20 min reperfusion period, hemodynamic parameters were compared among the three groups. After the 45 min ischemia and 120 min reperfusion period, tissue samples were obtained from the rat hearts, and MDA, SOD, GSH-Px, IL-1β and TNF-α levels were compared.MDA and GSH-Px levels were significantly higher in the control group compared to the ketamine and dexmedetomidine groups. However, both levels were similar in the ketamine and dexmedetomidine groups. SOD levels were significantly lower in the ketamine and dexmedetomidine groups compared to the control group, but they were similar in the ketamine and dexmedetomidine groups. IL-1β levels were similar in all groups. TNF-α levels were significantly lower in the ketamine and dexmedetomidine groups compared to the control group. They were similar in the ketamine and dexmedetomidine groups.According to our study, it can be concluded that dexmedetomidine and ketamine have similar effects on reducing myocardial ischemia reperfusion injury. Dexmedetomidine provides better heart rate control but causes hypotension, so, because of cardiac depression, we think that its clinical use may necessitate further investigation. |
| 2014 | Hypotensive effects of omentin-1 related to increased adiponectin and decreased interleukin-6 in intra-thoracic pericardial adipose tissue. | Pharmacol Rep | Omentin is an adipokine expressed in visceral adipose tissue (VAT). In vitro studies demonstrated that omentin induces vasorelaxation in isolated rat mesenteric arteries, and in vivo studies showed inhibition of agonist-induced increases in blood pressure, possibly mediated by nitric oxide (NO)-dependent mechanisms.We investigated, in normotensive rats, the effects of subacute omentin-1 administration [8μg/kg, intraperitoneally (ip), once daily for 14 days] on cardiac activity, blood pressure, plasma concentration of l-citrulline (as a marker of NO production from l-arginine), and the gene expression of adiponectin, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in intra-thoracic pericardial adipose tissue (PAT). Electrocardiography (ECG), heart rate (HR), mean blood pressure (MBP), pulse pressure (PP) were monitored before and after treatment with omentin-1 or vehicle.With respect to baseline and vehicle, we found a significant decrease of MBP (p<0.005) and PP (p<0.05) after treatment with omentin-1, while ECG and HR were not modified. Omentin-1 significantly increased l-citrulline levels in plasma (p<0.05), and the gene expression of adiponectin in PAT (p<0.05). On the other hand, we found decreased gene expression of IL-6 (p<0.005), while TNF-α mRNA in PAT was not affected.We conclude that the hypotensive effects of omentin-1 could be driven by stimulated production of NO in the vascular system, possibly related to increased adiponectin and decreased IL-6 mRNA in PAT. |
| 2014 | Effects of selective β1-adrenoceptor blockade on cardiovascular and renal function and circulating cytokines in ovine hyperdynamic sepsis. | Crit Care | Activation of the sympathetic nervous system has beneficial cardiovascular effects in sepsis, but there is also evidence that sympatholytics have beneficial actions in sepsis. We therefore determined the effect of selective β1-adrenoceptor blockade on cardiac and renal function and cytokine release in ovine hyperdynamic sepsis.Hyperdynamic sepsis was induced by infusion of live E. coli for 24 hours in nine conscious sheep instrumented with flow probes on the pulmonary and left renal artery. Cardiovascular and renal function and levels of plasma cytokines were determined in a control group and during selective β1-adrenoceptor blockade with atenolol (10 mg intravenous bolus then 0.125 mg/kg/h) from 8 to 24 hours of sepsis.Hyperdynamic sepsis was characterized by hypotension with increases in cardiac output (CO), heart rate (HR) and renal blood flow (RBF), and acute kidney injury. Atenolol caused sustained reductions in HR (P < 0.001) and CO (P < 0.001). Despite the lower CO the sepsis-induced fall in mean arterial pressure (MAP) was similar in both groups. The sepsis-induced increase in RBF, decrease in renal function and increase in arterial lactate were unaffected by atenolol. Sepsis increased plasma levels of tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and IL-10. Atenolol caused a further increase in IL-10, but did not affect levels of TNF-α or IL-6.In sepsis, selective β1-adrenoceptor blockade reduced CO, but not MAP. During sepsis, atenolol did not alter the development of acute kidney injury or the levels of pro-inflammatory cytokines, but enhanced the release of IL-10. Atenolol appears safe in sepsis, has no deleterious cardiovascular or renal effects, and has an anti-inflammatory effect. |
| 2014 | Dexamethasone improves heat stroke-induced multiorgan dysfunction and damage in rats. | Int J Mol Sci | Dexamethasone (DXM) is known as an immunosuppressive drug used for inflammation control. In the present study, we attempted to examine whether DXM administration could attenuate the hypercoagulable state and the overproduction of pro-inflammatory cytokines, improve arterial hypotension, cerebral ischemia and damage, and vital organ failure in a rat model of heat stroke. The results indicated that all the rats suffering from heat stroke showed high serum levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), accompanied with increased prothrombin time, activated partial thromboplastin time and D-D dimer, and decreased protein C. During the induction period of heat stroke, plasma levels of blood urea nitrogen (BUN), creatinine, glutamic oxaloacetic transaminase (SGOT), glutamic pyruvic transaminase (SGPT), and alkaline phosphatase (ALP), were consistently increased. High striatal levels of glycerol, glutamate, and lactate/pyruvate were simultaneously detected. On the contrary, the mean arterial pressure, plasma levels of interleukin-10 (IL-10), and local cerebral blood flow at the striatum were all decreased. Importantly, intravenous administration of DXM substantially ameliorated the circulatory dysfunction, systematic inflammation, hypercoagulable state, cerebral ischemia and damage during the induction period of heat stroke. These findings demonstrated that DXM may be an alternative therapy that can ameliorate heat stroke victims by attenuating activated coagulation, systemic inflammation, and vital organ ischemia/injury during heat stroke. |
| 2014 | [Effect of urapidil combined with phentolamine on hypertension during extracorporeal circulation]. | Nan Fang Yi Ke Da Xue Xue Bao | To study the effect of urapidil combined with phentolamine in the management of hypertension during extracorporeal circulation.Ninety patients undergoing aortic and mitral valve replacement were randomly divided into 3 equal groups to receive treatment with phentolamine (group A), urapidil (group B), or both (group C) during extracorporeal circulation. The mean arterial pressure (MAP) before and after drug administration, time interval of two administrations, spontaneous recovery of heart beat after aorta unclamping, ventricular arrhythmia, changes of ST-segment 1 min after the recovery of heart beat, ante-parallel cycle time, aorta clamping time, post-parallel cycle time, dopamine dose after cardiac resuscitation, and perioperative changes of plasma TNF-α and IL-6 levels were recorded.There was no significant difference in MAP between the 3 groups before or after hypotensive drug administration (P>0.05). The time interval of two hypotensive drug administrations was longer in group C than in groups A and B (P<0.05). The incidence of spontaneous recovery of heart beat after aorta unclamping, incidence of ventricular arrhythmia, changes of ST-segment 1 min after the recovery of heart beat, ante-parallel cycle time, aorta clamping time, and post-parallel cycle time were all comparable between the 3 groups. The dose of dopamine administered after cardiac resuscitation was significantly larger in group B than in groups A or group C (P<0.05). The plasma levels of TNF-α and IL-6 were significantly increased after CPB and after the operation in all the groups, but were lowed in group C than in groups A and B at the end of CPB and at 2 h and 12 after the operation.Urapidil combined with phentolamine can control hypertension during extracorporeal circulation without causing hypotension. |
| 2014 | Intraintestinal drainage as a damage control surgery adjunct in a hypothermic traumatic shock swine model with multiple bowel perforations. | J Surg Res | Temporary bowel ligation (TL) has been proposed to prevent contamination as a damage control procedure in multiple bowel perforations. However, bacteria translocation and intestinal ischemia may develop in a prolonged duration. We here hypothesized that intraintestinal drainage combined with temporary ligation (D-TL) would decrease intestinal injury and improve survivals in a gunshot multiple bowel perforation swine model in the setting of a damage control surgery.The abdomen was shot one time with an experimental modified gun whereas pigs were hemorrhaged to a mean arterial pressure of 40 mm Hg and maintained in shock for 40 min. Cold lactated Ringer solution was gradually infused to induce hypothermia. Animals were randomized to primary anastomosis, TL and intraintestinal D-TL groups (n = 8). Animals were resuscitated for 12 h with the shed blood and lactated Ringer solution. Delayed anastomosis was performed in TL and D-TL animals after resuscitation. Surviving animals were humanely killed 24 h after operation. Systemic hemodynamic parameters were recorded and blood samples were obtained for biochemical assays. Intra-abdominal pressure, portal vein and peripheral vein bacterial cultures, small intestine hematoxylin-eosin staining, and transmission electron microscopy examination were performed at 0, 2, 6, 12, and 24 h after the surgery.All animals suffered extreme physiologic conditions as follows: hypothermia, severe acidosis, hypotension, and depressed cardiac output. Compared with the primary anastomosis and TL group, D-TL animals required less resuscitation fluid, suffered a lower intra-abdominal hypertension and bacterial translocation, normalized lactate levels faster, had lower serum creatine kinase, aspartate aminotransferase levels and tissue TNF-α level, and nuclear factor-kB activations and thus had greater early survival.Compared with primary intestinal anastomosis and TL, rapid bowel ligation combined with intraintestinal drainage as a damage control adjunct improved survivals in a multiple bowel perforation swine model in the setting of damage control surgery. |
| 2014 | [Effects of different anesthesia depth on stress response in elderly patients undergoing elective laparoscopic surgery for colorectal cancer]. | Nan Fang Yi Ke Da Xue Xue Bao | To investigate the effects of different anesthesia depth on stress response in elderly patients undergoing elective laparoscopic surgery for colorectal cancer.A total of 105 ASA I-III patients aged 60-91 years undergoing elective laparoscopic surgery for colorectal cancer with general anesthesia were randomized into 3 groups, namely group A with a target Narcotrend index (NI) maintained at D0 level, group B with a NI at D2 level, and group C with a NI at E1 level. The anesthetics (profopol and remifentanil) were adjusted according to Narcotrend monitoring results to maintain the specified anesthesia depth. The patients' heart rate (HR) and mean artery pressure (MAP) were recorded before anesthesia (T0), before intubation (T1), immediately after intubation (T2), at 2 min before pneumoperitoneum (T3), 2 min after pneumoperitoneum (T4), at the end of the surgery (T5) and extubation (T6). Serum levels of cortisol, adrenocorticotropic hormone (ACTH), endothelin-1 (ET-1), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) were measured by standard ELISA and radioimmunoassay before anesthesia (Ta), at the end of the surgery (Tb) and 1 day after the surgery (Tc).HR and MAP in group A increased significantly at T2, T4, and T6 compared to those at T0 (P<0.05), and were higher than those in group B and group C (P<0.05). The MAP in all the 3 groups all decreased at T1 and T3 (P<0.05 or P<0.01), and was markedly lower in group C than in groups A and B (P<0.05). The incidence of hypertension was significantly higher in group A than in groups B and C (P<0.05), while the incidence of hypotension was much higher in group C (P<0.01). There were no obvious differences in serum levels of cortisol, ACTH, CRP, IL-6, TNF-a, or ET-1 among the groups at Ta (P>0.05). The serum levels of ACTH in the 3 groups all significantly increased at Tb and Tc (P<0.01). CRP, IL-6 and TNF-a levels in group A were increased at Tb and Tc (P<0.05 or P<0.01) and significantly higher than those in groups B and C (P<0.05 or P<0.01). Cortisol in groups A and B increased at Tb and Tc (P<0.05) to a significantly higher level than that in group C (P<0.01). ET-1 level in group C at Tb and Tc was lower than those in groups A and B (P<0.05 or P<0.01).Maintaining the anesthesia depth for a NI at the D2 and E1 level can both attenuate the stress response in elderly patients undergoing laparoscopic surgery for colorectal cancer, but the hemodynamic stability can be better at a D2 level. |
| 2014 | Mesenteric lymph drainage alleviates acute kidney injury induced by hemorrhagic shock without resuscitation. | ScientificWorldJournal | This study aimed to investigate the effect of mesenteric lymph drainage on the acute kidney injury induced by hemorrhagic shock without resuscitation. Eighteen male Wistar rats were randomly divided into sham, shock, and drainage groups. The hemorrhagic shock model (40 mmHg, 3 h) was established in shock and drainage groups; mesenteric lymph drainage was performed from 1 h to 3 h of hypotension in the drainage group. The results showed that renal tissue damage occurred; the levels of urea, creatinine, and trypsin in the plasma as well as intercellular adhesion molecule-1 (ICAM-1), receptor of advanced glycation end-products (RAGE), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), lactic acid (LA), and 2,3-DPG in the renal tissue were increased in the shock group after 3 h of hypotension. Mesenteric lymph drainage lessened the following: renal tissue damage; urea and trypsin concentrations in the plasma; ICAM-1, RAGE, TNF-α, MDA, and LA levels in the renal tissue. By contrast, mesenteric lymph drainage increased the 2,3-DPG level in the renal tissue. These findings indicated that mesenteric lymph drainage could relieve kidney injury caused by sustained hypotension, and its mechanisms involve the decrease in trypsin activity, suppression of inflammation, alleviation of free radical injury, and improvement of energy metabolism. |
| 2014 | Optimizing anesthetic regimen for surgery in mice through minimization of hemodynamic, metabolic, and inflammatory perturbations. | Exp Biol Med (Maywood) | The role of anesthetics in animal research models is crucial, yet often ignored, and is almost never the primary focus of examination. Here, we investigated the impact of anesthetic regimens on different parameters of hemodynamics (blood pressure (BP) and heart rate (HR)), metabolism (glucose, insulin, and free fatty acids (FFA)), and inflammation (IL-6 and TNF-α) in two frequently used mouse strains (C57BL/6 and FVB). All animals were at a similar surgical plane of anesthesia, mechanically ventilated, and monitored for 60 min. The following anesthetic regimens were studied: (1) fentanyl-ketamine-midazolam (FKM), (2) fentanyl-midazolam-haldol (FMH), (3) pentobarbital (P), (4) fentanyl-fluanisone-midazolam (FFM), (5) fentanyl-midazolam-acepromazine (FMA), (6) ketamine-medetomidine-atropine (KMA), (7) isoflurane (ISO), and (8) propofol-fentanyl-midazolam (PFM). Metabolic and inflammatory parameters were compared with those obtained from non-anesthetized animals. Hemodynamics: BP >80 mm Hg were only obtained with KMA, whereas hypotension (BP <60 mm Hg) was observed with FKM and P. HR >500 beats/min was observed with ISO and PFM, whereas HR <400 beats/min was induced with KMA, FMH (BL/6), P (BL/6), and FKM (FVB). Metabolism: Glucose and insulin were most disturbed by KMA and ISO and mildly disturbed by FMA, whereas FFM, PFM, and P did not have any effect. FFA increased largely by FMA, with ISO and FKM having no effects. Inflammation: Cytokines were increased least with ISO/FFM/FMA, whereas FKM and KMA induced the largest increases in cytokines. When aiming at achieving surgical anesthesia without large disturbances in hemodynamic, metabolic, and inflammatory profiles, FFM, ISO, or PFM may be the most neutral anesthetic regimens in mice. |
| 2014 | Paternal low protein diet affects adult offspring cardiovascular and metabolic function in mice. | Am J Physiol Heart Circ Physiol | Although the association between maternal periconceptional diet and adult offspring health is well characterised, our understanding of the impact of paternal nutrition at the time of conception on offspring phenotype remains poorly defined. Therefore, we determined the effect of a paternal preconception low protein diet (LPD) on adult offspring cardiovascular and metabolic health in mice. Male C57BL/6 mice were fed either normal protein diet (NPD; 18% casein) or LPD (9% casein) for 7 wk before mating. At birth, a reduced male-to-female ratio (P = 0.03) and increased male offspring weight (P = 0.009) were observed in litters from LPD compared with NPD stud males with no differences in mean litter size. LPD offspring were heavier than NPD offspring at 2 and 3 wk of age (P < 0.02). However, no subsequent differences in body weight were observed. Adult male offspring derived from LPD studs developed relative hypotension (decreased by 9.2 mmHg) and elevated heart rate (P < 0.05), whereas both male and female offspring displayed vascular dysfunction and impaired glucose tolerance relative to NPD offspring. At cull (24 wk), LPD males had elevated adiposity (P = 0.04), reduced heart-to-body weight ratio (P = 0.04), and elevated circulating TNF-α levels (P = 0.015) compared with NPD males. Transcript expression in offspring heart and liver tissue was reduced for genes involved in calcium signaling (Adcy, Plcb, Prkcb) and metabolism (Fto) in LPD offspring (P < 0.03). These novel data reveal the impact of suboptimal paternal nutrition on adult offspring cardiovascular and metabolic homeostasis, and provide some insight into the underlying regulatory mechanisms. |
| 2014 | Adrenal dysfunction in portal hypertensive rats with acute hemorrhage. | PLoS One | Nitric oxide (NO) participates in shock and poorer portal hypotensive effect to vasoconstrictors in portal hypertension with hemorrhage, the so-called splanchnic hyposensitivity. Relative adrenal insufficiency accompanies hemorrhagic shock and is found in liver disease, the 'hepatoadrenal syndrome', but the relevant interactions remain unsettled. Portal hypertensive rats were induced by partial portal vein ligation (PVL). Experiments were performed on the 14th day post PVL: (I) ACTH stimulation test for rats without or with hemorrhage; (II) Glypressin response (mean arterial pressure, MAP; portal pressure, PP) in rats (a) without hemorrhage or with hemorrhage, injected with (b) distilled water (DW), (c) dexamethasone 3 mg/kg; (III) To survey the dose-dependent effects of glucocorticoid without being confounded by endogenous adrenal hormone, glypressin response was surveyed in PVL rats with adrenalectomy: (a) without hemorrhage or with hemorrhage, injected with (b) DW; (c) dexamethasone 3 mg/kg; (d) dexamethasone 5 mg/kg. Plasma tumor necrosis factor-α (TNF-α) concentrations and abdominal aorta (AA), superior mesenteric artery (SMA) NO synthases (NOS) mRNA expressions were determined. The results showed that ACTH induced corticosterone release similarly in PVL rats with or without hemorrhage. In bleeding PVL rats, dexamethasone (1) down-regulated AA NOS and enhanced glypressin-induced MAP elevation; (2) did not influence glypressin-induced PP reduction; (3) reduced TNF-α. In bleeding PVL and adrenalectomized rats, high-dose dexamethasone (1) down-regulated AA/SMA NOS; (2) enhanced glypressin-induced MAP elevation and PP reduction; (3) reduced TNF-α. In conclusion, bleeding portal hypertensive rats failed to enhance corticosterone release, suggesting a relative adrenal insufficiency. High-dose dexamethasone reversed systemic hypotension and splanchnic hyporesponsiveness to glypressin in adrenalectomized PVL rats accompanied by TNF-α and NOS down-regulation, suggesting the importance of adequate adrenocorticoid supplement in portal hypertension with hemorrhage and adrenal dysfunction. |
| 2014 | Primary effusion lymphoma-like lymphoma in a patient with inflammatory bowel disease. | World J Gastroenterol | A 77-year-old man with inflammatory bowel disease (IBD) and who was treated with anti-tumor necrosis factor (TNF), 6-mercaptopurine and corticosteroids, presented with primary effusion lymphoma-like lymphoma (PEL-like lymphoma) with massive ascites. The patient's clinical course was complicated by acute renal insufficiency and hypotension, which led to death within 2 wk. In general, patients with IBD may have an increased risk for development of lymphoma, which is frequently associated with immunosuppressive and/or anti-TNF antibody therapies. PEL is a rare subset of lymphoma localized to serous body cavities, lacks tumor mass or nodal involvement, and is associated with infection by human herpes virus 8 (HHV-8). Primary neoplastic effusion may also be present in patients with large B-cell lymphoma without evidence of human immunodeficiency virus or HHV-8 infections. This type of lymphoma is classified as PEL-like lymphoma. Both PEL and PEL-like lymphoma types have been reported in patients undergoing immunosuppressive therapy, but to the best of our knowledge, the case described herein represents the first PEL-like lymphoma occurring in a patient with IBD. |
| 2014 | Increased concentration of serum TNF alpha and its correlations with arterial blood pressure and indices of renal damage in dogs infected with Babesia canis. | Parasitol Res | Canine babesiosis is a tick-borne disease caused by parasites of the genus Babesia. Tumour necrosis factor alpha (TNF-α) is a cytokine that plays a role in the pathogenesis of canine babesiosis. In this study, the authors determined the concentration of serum TNF-α in 11 dogs infected with Babesia canis and calculated Spearman's rank correlations between the concentration of TNF-α and blood pressure, and between TNF-α and indices of renal damage such as: fractional excretion of sodium (FE(Na(+))), urinary creatinine to serum creatinine ratio (UCr/SCr), renal failure index (RFI), urine specific gravity (USG) and urinary protein to urinary creatinine ratio (UPC). The results demonstrated statistically significant strong negative correlations between TNF-α and systolic arterial pressure (r = -0.7246), diastolic arterial pressure (r = -0.6642) and mean arterial pressure (r = -0.7151). Serum TNF-α concentration was also statistically significantly correlated with FE(Na(+)) (r = 0.7056), UCr/SCr (r = -0.8199), USG (r = -0.8075) and duration of the disease (r = 0.6767). The results of this study show there is an increase of serum TNF-α concentration during canine babesiosis, and the increased TNF-α concentration has an influence on the development of hypotension and renal failure in canine babesiosis. This probably results from the fact that TNF-α is involved in the production of nitric oxide and induction of vasodilation and hypotension, which may cause renal ischaemia and hypoxia, and finally acute tubular necrosis and renal failure. |
| 2013 | [Side effects and contraindications for biological therapy in inflammatory bowel disease]. | Acta Med Croatica | TNF-alpha blockers side effects vary according to the frequency and severity and mainly include immunogenicity (ability to cause immune reactions), infections, malignancies, heart failure, demyelinating disease and others. Treatment with TNF-alpha blockers may result in the formation of autoantibodies and, rarely, in the development of a lupus-like syndrome. They should not be administered to patients who have experienced a severe hypersensitivity reaction. Urticaria, dyspnea and hypotension can occur after TNF-alpha inhibitors administration. Serious infusion reactions including anaphylaxis are infrequent. Patients treated with TNF-alpha blockers are at increased risk for developing serious infections (active tuberculosis, including reactivation of latent TB, invasive fungal infections, bacterial, viral, and also infections due to opportunistic pathogens). Therefore, all patients should be screened for systemic or localized infection before starting therapy. Patients with a positive screening for TB should be treated with isoniazid for at least 4 weeks, before starting TNF-alpha blocker therapy. TNF-alpha blockers may be associated with non-Hodgkin lymphoma or other cancers especially if combined with other immunosuppressive drugs. Monotherapy showed no such effect in patients, who cited a personal history of malignant disease, therefore caution is needed. TNF-alpha blockers are contraindicated in patients with moderate to severe congestive heart failure (NYHA Class III/IV). TNF-alpha blockers have been associated with reactivation of hepatitis B virus (HBV) infection in patients who are chronic carriers. Patients should be tested for HBV infection before treatment. Patients who test positive should be monitored closely for reactivation of HBV infection during and following termination of therapy. Patients with negative serology should be vaccinated. Severe hepatic reactions, including acute liver failure, jaundice, hepatitis, and cholestasis have been reported. Patients with symptoms or signs of liver dysfunction should be evaluated for evidence of liver injury. Cases of leucopenia, neutropenia, thrombocytopenia, and pancytopenia have been reported. TNF-alpha blockers have been associated in rare cases with CNS manifestation of systemic vasculitis, new onset or exacerbation of CNS and peripheral demyelinating disorders, including multiple sclerosis and Guillain-Barré syndrome. |
| 2013 | [Clinical experience of double plasma molecular absorption with a combination of two hemoperfusion machines in treatment of liver failure]. | Zhonghua Wei Zhong Bing Ji Jiu Yi Xue | To evaluate the effect of the double plasma molecular adsorption system (DPMAS) with a combination of two hemoperfusion machines in treatment of liver failure.A retrospective analysis was conducted. The clinical data from 42 patients with liver failure admitted to Tianjin Second People's Hospital from September 2012 to September 2013 were enrolled. Patients received 166 courses of blood purification treatment, including 97 courses of plasmapheresis (PE) and 69 courses of DPMAS. The DPMAS treatment was performed with a combination of two hemoperfusion machines, with one a blood pump and the other a plasma pump, for 2-3 hours. Liver function, tumor necrosis factor-α (TNF-α), electrolytes and blood routine were determined before and after treatment. Adverse reactions were observed and the nursing experiences were summarized.The survival rate of 42 liver failure patients was 64.29%, and the total bilirubin (TBil), NH3, total bile acid (TBA) and TNF-α were decreased and the albumin (ALB) was increased after PE and DPMAS. Further analysis of the rate of changes after treatment (after treatment/before treatment×100%) showed that when compared with that in DPMAS, the TBil and TBA were decreased significantly in PE [TBil: (62.21 ± 5.51)% vs. (64.39 ± 4.61)%, t=2.683, P=0.008; TBA: (77.10 ± 4.44)% vs. (85.91 ± 6.95)%, t=9.952, P=0.000], and the level of ALB was elevated significantly in PE when compared with that in DPMAS [(113.12 ± 2.90)% vs. (101.87 ± 2.91)%, t=24.602, P=0.000]. NH3 and TNF-α were decreased in both groups withe no statistical significance [NH3: (79.59 ± 5.72)% vs. (80.56 ± 7.56)%, t=0.934, P=0.351; TNF-α: (61.66 ± 4.67)% vs. (62.73 ± 3.67)%, t=1.638, P=0.108]. The blood electrolytes and routine blood test showed that there was no significant change before and after treatments in DPMAS group (K⁺: 3.92 ± 0.83 mmol/L vs. 3.91 ± 0.82 mmol/L, t=0.501, P=0.618; Na⁺: 136.89 ± 5.69 mmol/L vs. 136.74 ± 5.83 mmol/L, t=1.077, P=0.285; Cl⁻: 96.58 ± 3.33 mmol/L vs. 96.55 ± 3.27 mmol/L, t=0.245, P=0.807; white cell count: 5.22 ± 0.93 × 10⁹/L vs. 5.43 ± 1.11 × 10⁹/L, t=1.125, P=0.265; hemoglobin: 110.97 ± 19.20 g/L vs. 112.69 ± 19.67 g/L, t=0.643, P=0.522; platelet count: 105.28 ± 26.82 × 10⁹/L vs. 101.96 ± 3.08 × 10⁹/L, t=0.727, P=0.470). Sixty-four out of the 69 courses of DPMAS treatment were successfully completed, and 5 times were ended because of line coagulation. There was no uncomfortable symptom complained by 53 patients during the treatment. Hypotension occurred for 3 times, and discomfort and nausea during treatment were complained for 9 times. Low fever occurred 4 times after treatment. Those uncomfortable symptoms were relieved spontaneously or by symptomatic treatment. Psychological nursing care should be given to the patients before and after DPMAS to relieve anxiety. Circulating tubes should be well rinsed to prevent line coagulation. General condition of the patient should be closely monitored in order to adjust therapeutic measures.DPMAS could be effectively performed with a combination of two hemoperfusion machines without inadvertent side reactions, and it is safe in operation with smaller amount of plasma. |
| 2014 | Safety of poly (ethylene glycol)-coated perfluorodecalin-filled poly (lactide-co-glycolide) microcapsules following intravenous administration of high amounts in rats. | Results Pharma Sci | The host response against foreign materials designates the biocompatibility of intravenously administered microcapsules and thus, widely affects their potential for subsequent clinical use as artificial oxygen/drug carriers. Therefore, body distribution and systemic parameters, as well as markers of inflammation and indicators of organ damage were carefully evaluated after administration of short-chained poly (vinyl alcohol, (PVA)) solution or poly (ethylene glycol (PEG))-shielded perfluorodecalin-filled poly (d,l-lactide-co-glycolide, PFD-filled PLGA) microcapsules into Wistar rats. Whereas PVA infusion was well tolerated, all animals survived the selected dose of 1247 mg microcapsules/kg body weight but showed marked toxicity (increased enzyme activities, rising pro-inflammatory cytokines and complement factors) and developed a mild metabolic acidosis. The observed hypotension emerging immediately after start of capsule infusion was transient and mean arterial blood pressure restored to baseline within 70 min. Microcapsules accumulated in spleen and liver (but not in other organs) and partly occluded hepatic microcirculation reducing sinusoidal perfusion rate by about 20%. Intravenous infusion of high amounts of PFD-filled PLGA microcapsules was tolerated temporarily but associated with severe side effects such as hypotension and organ damage. Short-chained PVA displays excellent biocompatibility and thus, can be utilized as emulsifier for the preparation of drug carriers designed for intravenous use. |
| 2014 | Assessment of coagulopathy, endothelial injury, and inflammation after traumatic brain injury and hemorrhage in a porcine model. | J Trauma Acute Care Surg | Traumatic brain injury (TBI) and hemorrhagic shock (HS) can be associated with coagulopathy and inflammation, but the mechanisms are poorly understood. We hypothesized that a combination of TBI and HS would disturb coagulation, damage the endothelium, and activate inflammatory and complement systems.A total of 33 swine were allocated to either TBI + HS (n = 27, TBI and volume-controlled 40% blood loss) or controls (n = 6, anesthesia and instrumentation). TBI + HS animals were left hypotensive (mean arterial pressure, 30-35 mm Hg) for 2 hours. Blood samples were drawn at baseline, 3 minutes and 15 minutes after injury, as well as following 2 hours of hypotension. Markers of coagulation, anticoagulation, endothelial activation/glycocalyx shedding, inflammation, complement, and sympathoadrenal function were measured.The TBI + HS group demonstrated an immediate (3 minutes after injury) activation of coagulation (prothrombin fragment 1 + 2, 289 ng/mL vs. 232 ng/mL, p = 0.03) and complement (C5a, 2.83 ng/mL vs. 2.05 ng/mL, p = 0.05). Shedding of the endothelial glycocalyx (syndecan 1) was evident 15 minutes after injury (851.0 ng/ml vs. 715.5 ng/ml, p = 0.03) while inflammation (tumor necrosis factor α [TNF-α], 81.1 pg/mL vs. 50.8 pg/mL, p = 0.03) and activation of the protein C system (activated protein C, 56.7 ng/mL vs. 26.1 ng/mL, p = 0.01) were evident following the 2-hour hypotension phase.The combination of TBI and shock results in an immediate activation of coagulation and complement systems with subsequent endothelial shedding, protein C activation, and inflammation. |
| 2013 | Treating inflammation by blocking interleukin-1 in humans. | Semin Immunol | IL-1 is a master cytokine of local and systemic inflammation. With the availability of specific IL-1 targeting therapies, a broadening list of diseases has revealed the pathologic role of IL-1-mediated inflammation. Although IL-1, either IL-1α or IL-1β, was administered to patients in order to improve bone marrow function or increase host immune responses to cancer, these patients experienced unacceptable toxicity with fever, anorexia, myalgias, arthralgias, fatigue, gastrointestinal upset and sleep disturbances; frank hypotension occurred. Thus it was not unexpected that specific pharmacological blockade of IL-1 activity in inflammatory diseases would be beneficial. Monotherapy blocking IL-1 activity in a broad spectrum of inflammatory syndromes results in a rapid and sustained reduction in disease severity. In common conditions such as heart failure and gout arthritis, IL-1 blockade can be effective therapy. Three IL-1blockers have been approved: the IL-1 receptor antagonist, anakinra, blocks the IL-1 receptor and therefore reduces the activity of IL-1α and IL-1β. A soluble decoy receptor, rilonacept, and a neutralizing monoclonal anti-interleukin-1β antibody, canakinumab, are also approved. A monoclonal antibody directed against the IL-1 receptor and a neutralizing anti-IL-1α are in clinical trials. By specifically blocking IL-1, we have learned a great deal about the role of this cytokine in inflammation but equally important, reducing IL-1 activity has lifted the burden of disease for many patients. |
| 2013 | Inhibition of poly (adenosine diphosphate-ribose) polymerase attenuates lung-kidney crosstalk induced by intratracheal lipopolysaccharide instillation in rats. | Respir Res | Acute respiratory distress syndrome (ARDS) is a severe form of lung injury that frequently occurs during pneumonia and sepsis. Lung inflammation in ARDS patients may have deleterious effects on remote organs such as the kidney. The nuclear enzyme poly(adenosine diphosphate-ribose) polymerase (PARP) enhances the nuclear factor (NF)-κB-dependent transcription of inflammatory cytokines. This study was conducted to elucidate two questions: first, whether the activation of PARP and NF-κB mediates the renal inflammation secondary to the lipopolysaccharide (LPS)-induced acute lung inflammation; second, whether a PARP inhibitor, 3-aminobenzamide (3-AB), attenuates lung and kidney inflammation by inhibiting NF-κB-dependent proinflammatory cytokines.Male Sprague-Dawley rats were anesthetized, ventilated, and divided into three groups; a control group (n = 8); an LPS group (n = 12) intratracheally instilled with LPS (16 mg/kg), and an LPS + 3-AB group (n = 12) given the same dose of LPS by the same method followed by an intravenous injection of 3-AB (20 mg/kg). Hemodynamics, arterial blood gas, and the plasma levels of lactate, creatinine and potassium were measured at 0,1,2,3, and 4 h after treatment. The lung wet/dry ratio was measured at 4 h. The mRNA expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in the lung and kidney were measured by TaqMan real-time PCR. PARP and NF-κB in the lung and kidney were histologically examined by immunostaining and assigned expression scores.LPS induced metabolic acidosis, hypotension, hypoxemia, increased the lung wet/dry ratio, increased the plasma levels of creatinine and potassium, and increased the cytokine mRNA expressions in the lung and kidney. All of these effects were associated with strong expression of PARP and NF-κB. Treatment with 3-AB prevented the LPS-induced metabolic acidosis and hypotension, reduced the plasma levels of lactate, creatinine and potassium, reduced the cytokine mRNA expressions, reduced the expression of PARP and NF-κB, improved pulmonary edema and oxygenation and preserved renal function.The PARP inhibition attenuated lung-kidney crosstalk induced by intratracheal LPS instillation, partly via an inhibition of NF-κB dependent proinflammatory cytokines. |
| 2013 | Phase I trial of a formulated IL-12 plasmid in combination with carboplatin and docetaxel chemotherapy in the treatment of platinum-sensitive recurrent ovarian cancer. | Gynecol Oncol | The primary objective of this study was to evaluate the safety and tolerability of a formulated IL-12 plasmid administered intraperitoneally (IP) in conjunction with intravenous (IV) carboplatin/docetaxel in platinum-sensitive ovarian cancer patients.Escalating doses of IL-12 plasmid (phIL-12) formulated with the lipopolymer PEG-PEI-Cholesterol (PPC) were administered IP every 10-11 days for a total of four treatments and the highest dose was expanded to eight treatments. Patients also received IV carboplatin (AUC 5) and docetaxel (75 mg/m(2)) every 21 days. Patients were followed for safety, biological activity and antitumor activity after phIL-12/PPC treatment.All 13 patients enrolled in the study received both phIL-12/PPC and chemotherapy treatment. There were 49 plasmid-associated adverse events (AEs). The most common AEs were abdominal pain, transient hypotension, low grade fever, catheter site pain, chills, dysgeusia, infusion-related reaction, and nausea. These AEs appeared to be plasmid dose related. Grade 3 AEs included manageable abdominal pain and cytokine release syndrome. There were no dose limiting toxicities and the plasmid treatment did not augment the chemotherapy-associated AEs. The best overall antitumor response (17% CR, 33% PR, 42% SD and 8% PD) was typical of the patient population enrolled for the study. Translational studies showed rise in IFN-γ and TNF-α concentrations in a dose dependent manner.The escalating doses and cycles of intraperitoneal phIL-12/PPC when combined with carboplatin/docetaxel chemotherapy in recurrent ovarian cancer patients were well tolerated and did not appear to exacerbate the side effects or attenuate the efficacy of the chemotherapy treatment. |
| 2013 | Contribution of iNOS/sGC/PKG pathway, COX-2, CYP4A1, and gp91(phox) to the protective effect of 5,14-HEDGE, a 20-HETE mimetic, against vasodilation, hypotension, tachycardia, and inflammation in a rat model of septic shock. | Nitric Oxide | We have previously demonstrated that a stable synthetic analog of 20-hydroxyeicosatetraenoic acid (20-HETE), N-[20-hydroxyeicosa-5(Z),14(Z)-dienoyl]glycine (5,14-HEDGE), prevents vascular hyporeactivity, hypotension, tachycardia, and inflammation in rats treated with lipopolysaccharide (LPS) and mortality in endotoxemic mice. These changes were attributed to decreased production of inducible nitric oxide (NO) synthase (iNOS)-derived NO, cyclooxygenase (COX)-2-derived vasodilator prostanoids, and proinflammatory mediators associated with increased cyctochrome P450 (CYP) 4A1-derived 20-HETE and CYP2C23-dependent antiinflammatory mediator formation. The aim of this study was to determine whether decreased expression and activity of iNOS, soluble guanylyl cyclase (sGC), protein kinase G (PKG), COX-2, gp91(phox) (NOX2; a superoxide generating NOX enzyme), and peroxynitrite production associated with increased expression of COX-1 and CYP4A1 and 20-HETE formation in renal and cardiovascular tissues of rats contributes to the effect of 5,14-HEDGE to prevent vasodilation, hypotension, tachycardia, and inflammation in response to systemic administration of LPS. Mean arterial pressure fell by 28mmHg and heart rate rose by 47beats/min in LPS (10mg/kg, i.p.)-treated rats. Administration of LPS also increased mRNA and protein expression of iNOS and COX-2 associated with a decrease in COX-1 and CYP4A1 mRNA and protein expression. Increased NOS activity, iNOS-heat shock protein 90 complex formation (an index for iNOS activity), protein expression of phosphorylated vasodilator stimulated phosphoprotein (an index for PKG activity), gp91(phox), p47(phox) (NOXO2; organizer subunit of gp91(phox)), and nitrotyrosine (an index for peroxynitrite production) as well as cGMP (an index for sGC activity), 6-keto-PGF1α (a stable metabolite PGI2) and PGE2 levels (indexes for COX activity), and nitrotyrosine levels by LPS were also associated with decreased CYP hydroxylase activity as measured by 20-HETE formation from arachidonic acid in renal microsomes of LPS-treated rats. These effects of LPS, except iNOS mRNA and COX-1 protein expression, were prevented by 5,14-HEDGE (30mg/kg, s.c.; 1h after LPS). A competitive antagonist of vasoconstrictor effects of 20-HETE, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid (30mg/kg, s.c.; 1h after LPS) reversed the effects of 5,14-HEDGE, except iNOS and COX-1 mRNA and protein expression as well as expression of CYP4A1 mRNA. These results suggest that increased CYP4A1 expression and 20-HETE formation associated with suppression of iNOS/sGC/PKG pathway, COX-2, and gp91(phox) participate in the protective effect of 5,14-HEDGE against vasodilation, hypotension, tachycardia, and inflammation in the rat model of septic shock. |
| 2013 | [Inflammatory-modulating mechanism of transcutaneous electrical acupoint stimulation combined with general anesthesia or controlled hypotension on postoperative hippocampal neuroprotection]. | Zhongguo Zhen Jiu | To observe the effects of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia or controlled hypotension on hippocampal neuronal damage and the inflammatory response in peripheral circulation and central nervous system (CNS) after surgery, and to investigate its brain protection mechanism.Eighteen healthy male beagles aged 6 - 8 months were randomly divided into a general anesthesia group (group G), a controlled hypotension group (group C) and a compound anesthesia acupuncture group (group A), 6 cases in each group. Dogs in group G was anesthetized by isoflurane inhalation, and group C was combined with intravenous infusion of sodium nitroprusside based on isoflurane inhalation to induce hypotension, and followed surgery after achieving the target blood pressure, and group A was combined with TEAS at "Quchi" (LI 11), "Hegu" (LI 4) "Zu sanli" (ST 36) and "Sanyinjiao" (SP 6) based on controlled hypotension, and then brain tissue was taken out on the 72 h after mean arterial pressure (MAP) was returned to baseline levels. The concentration of IL-1beta,TNF-alpha in serum at different time points were detected by ELISA. The expression of IL-1beta, TNF-alpha, Bcl-2, Bax and cleaved caspase-3 were measured by immunohistochemistry, and the apoptosis of hippocampus were detected by TUNEL.(1) At different time points, the concentration of TNFalpha showed the trend of increase first and then decrease, while IL-1beta concentration represented a trend of decrease first and then increase in both group C and group A, but there were no significant differences in cytokine expression between the two groups (all P > 0.05). (2) The ratio of positive cells of IL-1beta, TNF-alpha and caspase-3 in CA1 and CA3 of hippocampus in both group C and A were higher than those in group G (all P < 0.01), and cytokines expression in group A were lower than those in group C (all P < 0.01), and caspase-3 in CA1 in group A was lower than that in group C (P < 0.01). The ratio of Bcl-2/Bax in both group C and A were lower than that in group G (all P < 0.01), and that in group A was higher than that in group C (P < 0.01 in CA1, P < 0.05 in CA3). (3) The apoptosis index (AI) of hippocampal neurons in both group C and A was significantly higher than that in group G (P < 0.01), while AI in CA1 in group A was lower than that in group C (P < 0.01).The TEAS can regulate the expression of inflammatory factor in hippocampus in animals undergoing general anesthesia or con trolled hypotension surgery, further improving Bcl-2/Bax ratio, inhibiting the expression of caspase-3 and reducing neuron apoptosis in hippocampus so as to play a neuroprotection. |
| 2013 | Ephedrine hydrochloride inhibits PGN-induced inflammatory responses by promoting IL-10 production and decreasing proinflammatory cytokine secretion via the PI3K/Akt/GSK3β pathway. | Cell Mol Immunol | Approaches for controlling inflammatory responses and reducing the mortality rate of septic patients remain clinically ineffective; new drugs need to be identified that can induce anti-inflammatory responses. Ephedrine hydrochloride (EH) is a compound that is widely used in cardiovascular diseases, especially to treat hypotension caused by either anesthesia or overdose of antihypertensive drugs. In this study, we reported that EH also plays an important role in the control of the inflammatory response. EH increased IL-10 and decreased proinflammatory cytokine (IL-6, tumor-necrosis factor (TNF)-α, IL-12 and IL-1β) expression in primary peritoneal macrophages and Raw264.7 cells treated with peptidoglycan (PGN), a Gram-positive cell wall component. The anti-inflammatory role of EH was also demonstrated in an experimental mouse model of peritonitis induced by intraperitoneal PGN injection. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway was found to be responsible for the EH-mediated increase in IL-10 production and decrease in IL-6 expression. Therefore, our results illustrated that EH can help maintain immune equilibrium and diminish host damage by balancing the production of pro- and anti-inflammatory cytokines after PGN challenge. EH may be a new potential anti-inflammatory drug that can be useful for treating severe invasive Gram-positive bacterial infection. |
| 5,14-HEDGE, a 20-HETE mimetic, reverses hypotension and improves survival in a rodent model of septic shock: contribution of soluble epoxide hydrolase, CYP2C23, MEK1/ERK1/2/IKKβ/IκB-α/NF-κB pathway, and proinflammatory cytokine formation. | Prostaglandins Other Lipid Mediat | We have previously demonstrated that a stable synthetic analog of 20-HETE, N-[20-hydroxyeicosa-5(Z),14(Z)-dienoyl]glycine (5,14-HEDGE), restores vascular reactivity, blood pressure, and heart rate in endotoxemic rats. The aim of this study was to determine whether decreased renal expression and activity of soluble epoxide hydrolase (sEH), MEK1, ERK1/2, IKKβ, IκB-α, and NF-κB as well as systemic and renal proinflammatory cytokine production associated with increased expression and activity of CYP2C23 contributes to the effect of 5,14-HEDGE to prevent hypotension, tachycardia, inflammation, and mortality in response to systemic administration of lipopolysaccharide (LPS). Blood pressure fell by 33 mmHg and heart rate rose by 57 beats/min in LPS (10 mg/kg, i.p.)-treated rats. Administration of LPS also increased mRNA and protein expression of sEH associated with a decrease in CYP2C23 mRNA and protein expression. Increased activity of sEH and p-MEK1, p-ERK1/2, p-IκB-α, NF-κB, and p-NF-κB protein levels as well as TNF-α and IL-8 production by LPS were also associated with a decreased activity of AA epoxygenases. These effects of LPS were prevented by 5,14-HEDGE (30 mg/kg, s.c.; 1 h after LPS). Treatment of endotoxemic mice with 5,14-HEDGE also raised the survival rate of animals from 84% to 98%. A competitive antagonist of vasoconstrictor effects of 20-HETE, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid, 20-HEDE (30 mg/kg, s.c.; 1 h after LPS) prevented the effects of 5,14-HEDGE on blood pressure, heart rate, expression and/or activity of sEH, CYP2C23, and ERK1/2 as well as TNF-α and IL-8 levels in rats treated with LPS. These results suggest that decreased expression and/or activity of sEH and MEK1/ERK1/2/IKKβ/IκB-α/NF-κB pathway as well as proinflammatory cytokine production associated with increased CYP2C23 expression and antiinflammatory mediator formation participate in the protective effect of 5,14-HEDGE against hypotension, tachycardia, inflammation, and mortality in the rodent model of septic shock. |
| 2013 | Pneumonia-induced sepsis in mice: temporal study of inflammatory and cardiovascular parameters. | Int J Exp Pathol | The aim of the present work is to provide a better comprehension of the pneumonia-induced sepsis model through temporal evaluation of several parameters, and thus identify the main factors that determine mortality in this model. Klebsiella pneumoniae was inoculated intratracheally in anesthetized Swiss male mice. Inflammatory and cardiovascular parameters were evaluated 6, 24 and 48 h after the insult. The results show that severity of infection and the mortality correlated with the amount of bacteria. Six, 24 and 48 h after inoculation, animals presented pathological changes in lungs, increase in cell number in the bronchoalveolar lavage, leukopenia, increase in TNF-α and IL-1β levels, hypotension and hyporesponsiveness to vasoconstrictors, the two latter characteristics of severe sepsis and septic shock. Significant numbers of bacteria in spleen and heart homogenates indicated infection spreading. Interestingly, NOS-2 expression appeared late after bacteria inoculation, whereas levels of NOS-1 and NOS-3 were unchanged. The high NOS-2 expression coincided with an exacerbated NO production in the infection focus and in plasma, as judging by nitrate + nitrite levels. This study shows that K. pneumoniae inoculation induces a systemic inflammatory response and cardiovascular alterations, which endures at least until 48 h. K. pneumoniae-induced lung infection is a clinically relevant animal model of sepsis and a better understanding of this model may help to increase the knowledge about sepsis pathophysiology. |
| 2013 | Protective effects of dexmedetomidine on blunt chest trauma-induced pulmonary contusion in rats. | J Trauma Acute Care Surg | Dexmedetomidine is a new and highly selective α2-adrenoreceptor agonist with potent anti-inflammatory capacity. This study explored the effects of dexmedetomidine on regulating hemodynamics, the plasma tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) levels, immunohistochemical localization of nuclear factor κB (NF-κB) from blunt chest trauma-induced pulmonary contusion in rats.Fifty Sprague-Dawley rats were randomly assigned into five equal groups (n = 10) as follows: uninjured control group, uninjured plus dexmedetomidine group, injured group, injured plus dexmedetomidine group, injured plus dexmedetomidine plus yohimbine (IDY), an α2-adrenergic receptor antagonist, group. Dexmedetomidine was infused continuously through the left femoral vein cannula at the rate of 5.0 µg/kg per hour after blunt chest trauma 30 minutes in uninjured plus dexmedetomidine group, injured plus dexmedetomidine group, and IDY group. Animals in the IDY group received 0.2-mg/kg yohimbine immediately after the administration of dexmedetomidine. The right femoral artery was cannulated to monitor mean arterial pressure and heart rate and to draw blood samples. The plasma TNF-α and IL-1β levels were measured using enzyme-linked immunosorbent assays. The lung tissue NF-κB expression was determined by immunohistochemistry.Bilateral blunt chest trauma produced progressive hypotension and a prolonged descent in heart rate. The plasma TNF-α and IL-1β levels as well as the NF-κB activation of lung significantly increased after blunt chest trauma challenge alone. Dexmedetomidine not only significantly modified hemodynamics and relieved the infiltration of inflammatory cells into alveolar spaces but also inhibited the plasma TNF-α and IL-1β production as well as the lung NF-κB activation (p < 0.05, respectively). Yohimbine treatment significantly reversed the effects of dexmedetomidine (p < 0.05).The administration of dexmedetomidine has beneficial effects on pulmonary contusion from blunt chest trauma in rats. The mechanisms were likely to inhibit the NF-κB activation via α2-adrenergic receptors and attenuate the proinflammatory cytokine responses. |
| 2013 | Nandrolone decanoate determines cardiac remodelling and injury by an imbalance in cardiac inflammatory cytokines and ACE activity, blunting of the Bezold-Jarisch reflex, resulting in the development of hypertension. | Steroids | The aims of this study were to evaluate the effects of nandrolone (ND) on cardiac inflammatory cytokines, ACE activity, troponin I, and the sensitivity of the Bezold-Jarisch reflex (BJR). Male Wistar rats were administered either ND (20 mg/kg; DECA) or vehicle (control animals; CONT) for 4 weeks. BJR was analyzed by measuring the bradycardia and hypotension responses elicited by serotonin administration (2-32 μg/kg). Mean arterial pressure (MAP) was assessed and myocyte hypertrophy was determined by the heart weight/body weight ratio and by morphometric analysis. Matrix collagen deposition was assessed by histological analysis of the picrosirius red-stained samples. Mesenteric vascular reactivity was performed and central venous pressure (CVP) evaluated. Cardiac inflammatory cytokine levels and angiotensin-converting enzyme (ACE) activity were studied as well the biomarker of cardiac lesion, troponin I. DECA group showed enhancement of matrix type I collagen deposition (p < 0.01) and cardiac ACE activity (p < 0.01) compared with the CONT. Interleukin (IL)-10 was reduced (p < 0.01) and pro-inflammatory cytokines (TNF-α and IL-6; p < 0.01) were increased in the DECA group compared with CONT. Cardiac injury was observed in the DECA group shown by the reduction in cardiac troponin I (p < 0.01) compared with the CONT group. Animals in the DECA group also developed myocyte hypertrophy and reduction of BJR sensitivity. The MAP of animals treated with ND reached hypertensive levels (p < 0.01; compared with CONT). No changes in CVP and vascular reactivity were observed in both experimental groups. We conclude that high doses of ND elicit cardiotoxic effects with cardiac remodelling and injury. Cardiac changes reduce the BJR sensitivity. Together, these abnormalities contributed to the development of hypertension in animals in the DECA group. |
| 2013 | Lactoferrin moderates LPS-induced hypotensive response and gut injury in rats. | Int Immunopharmacol | Hypotension is a physiologic state of low blood pressure, the causes of which range from dehydration to underlying serious medical disorders. The aim of this study was to assess the utility of lactoferrin (LF), a natural immunomodulator, to restrain LPS-induced hypotension in rats. LF has previously demonstrated a role in mediation of immune responses, including control of inflammatory cytokine production during acute inflammation. Rats were administered with LF by gavage at 1h or 18 h prior to LPS injections. Heart rate (HR) and mean arterial blood pressure (MAP) were continuously recorded post LPS administration for 6 h. Simultaneously to hemodynamic measurements, serum was examined for TNF-α, IL-6, and TGF-β production. At termination, the proximal duodenum was subjected to histopathological analysis. LF administered at 1h prior to LPS protected rats from the LPS-induced hypotension. The protective effect on MAP was also apparent when LF was administered as a pretreatment 18 h prior to LPS challenge, although the effect was lessened. For all groups, LF pretreatment led to a minor, but insignificant, improvement in HR post LPS administration. In addition, when rats were given LF 1 h before LPS, they showed a significant decrease in serum TNF-α and IL-6 production. LF did not affect the production level of serum TGF-β. Of high importance, LF was able to confer histo-pathological protection of intestinal tissue post LPS administration, for both the 1h and 18 h LF pretreatment groups. These studies indicate a potential for clinical utility of LF to control hypotension. |
| 2013 | Cardiovascular and inflammatory response to cholecystokinin during endotoxemic shock. | Shock | Cholecystokinin (CCK) was first described as a gastrointestinal hormone, but its receptors have been located in cardiac and vascular tissues, as well as in immune cells. Our aims were to investigate the role of CCK on lipopolysaccharide (LPS)-induced hypotension and its ability to modulate previously reported inflammatory mediators, therefore affecting cardiovascular function. To conduct these experiments, rats had their jugular vein cannulated for drug administration, and also, the femoral artery cannulated for mean arterial pressure (MAP) and heart rate records. Endotoxemia induced by LPS from Escherichia coli (1.5 mg/kg; i.v.) stimulated the release of CCK, a progressive drop in MAP, and increase in heart rate. Plasma tumor necrosis factor α (TNF-α), interleukin 10 (IL-10), nitrate, vasopressin, and lactate levels were elevated in the endotoxemic rats. The pretreatment with proglumide (nonselective CCK antagonist; 30 mg/kg; i.p.) aggravated the hypotension and also increased plasma TNF-α and lactate levels. On the other hand, CCK (0.4 μg/kg; i.v.) administered before LPS significantly restored MAP, reduced aortic and hepatic inducible nitric oxide synthase (iNOS) production, and elevated plasma vasopressin and IL-10 concentrations; it did not affect TNF-α. Physiological CCK concentration reduced nitrite and iNOS synthesis by peritoneal macrophages, possibly through a self-regulatory IL-10-dependent mechanism. Together, these data suggest a new role for the peptide CCK in modulating MAP, possibly controlling the inflammatory response, stimulating the anti-inflammatory cytokine, IL-10, and reducing vascular and macrophage iNOS-derived nitric oxide production. Based on these findings, CCK could be used as an adjuvant therapeutic agent to improve cardiovascular function. |
| 2013 | Role of the transient receptor potential vanilloid type 1 channel in renal inflammation induced by lipopolysaccharide in mice. | Am J Physiol Regul Integr Comp Physiol | To determine the role of the transient receptor potential vanilloid type 1 (TRPV1) channel in the regulation of renal inflammation, lipopolysaccharide (LPS, 3 mg/kg) was intraperitoneally injected into wild-type (WT) and TRPV1-null mutant (TRPV1(-/-)) mice. The kidney and serum were collected 6 or 24 h after LPS injection for morphological analysis and proinflammatory cytokine assay. LPS injection led to a similar degree of transient hypotension and bradycardia in WT and TRPV1(-/-) mice determined by a telemetry system. LPS administration caused parenchymal red blood cell congestion and fading of intact glomerular structure in TRPV1(-/-) compared with WT mice. Serum creatinine levels were higher 24 h after LPS injection in TRPV1(-/-) than in WT mice. Neutrophil and macrophage infiltration in the kidneys was greater 6 h for the former and 24 h for both after LPS injection in TRPV1(-/-) than in WT mice. Serum cytokine levels including tumor necrosis factor (TNF)-α, IL-1β, and IL-6 were higher 6 h after LPS injection in TRPV1(-/-) compared with WT mice. Likewise, renal chemokine levels including keratinocyte-derived chemokines and macrophage inflammatory protein were higher 6 h after LPS injection in TRPV1(-/-) than in WT mice. Renal VCAM-1 and ICAM-1 expression was further elevated 6 h for the former and 24 h for the latter after LPS injection in TRPV1(-/-) than in WT mice. Renal nuclear factor-κB (NF-κB) activity was further increased 6 h after LPS injection in TRPV1(-/-) compared with WT mice. Pharmacological blockade TRPV1 in WT mice showed aggravated renal and serum inflammatory responses resembling that of TRPV1(-/-) mice. Thus TRPV1 gene ablation exacerbates LPS-induced renal tissue and function injury, including aggravated renal neutrophil and macrophage infiltration, chemokine and adhesion molecule levels, and glomerular hypercellularity accompanying with further increased serum creatinine and cytokine levels. These results indicate that TRPV1 is activated during LPS challenge, which may constitute a protect mechanism against LPS-induced renal injury via reducing renal inflammatory responses. |
| Determination of urine tumor necrosis factor, IL-6, IL-8, and serum IL-6 in patients with hemorrhagic fever with renal syndrome. | Braz J Infect Dis | The aim of this study was to explore the role of cytokines in the pathogenesis of hemorrhagic fever with renal syndrome (HFRS).Double-antibody sandwich ELISA was used to determine serum interleukin (IL)-6, urine tumor necrosis factor (TNF), IL-6, and IL-8 levels in 56 patients with HFRS.Serum IL-6, urine TNF, IL-6, and IL-8 concentrations in HFRS patients were significantly higher than those in the control group (p<0.001). The concentrations increased at fever stage, then continued to increase during the hypotension stage and peaked at the oliguria stage. The concentrations of serum IL-6, urine TNF, IL-6, and IL-8 increased according to the severity of the disease, and differed greatly among different types of the disease. Serum IL-6 had remarkable relationships with serum specific antibodies. It was positively related to serum β2-microglobulin (β2-MG), blood urea nitrogen (BUN), and creatinine (Cr). Significant positive relationships were also found both between urine IL-6 and TNF, and between IL-6 and IL-8 (r=0.5768, p<0.05; r=0.3760, p<0.01).TNF, IL-6, and IL-8 were activated during the course of the disease. IL-6 was associated with the immunopathological lesions caused by the hyperfunction of the humoral immune response. IL-6, IL-8 and TNF were involved in renal immune impairment. Determining them might, to a certain extent, be useful in predicting the prognosis and outcome of patients with HFRS. |
| 2013 | Detection of Legionella pneumophila serogroup 1 in blood cultures from a patient treated with tumor necrosis factor-alpha inhibitor. | J Infect Chemother | A 65-year-old man was admitted to our hospital with a temperature of 39.3 °C, cough, sputum, and pharyngeal discomfort that had persisted for 3 days. He had been treated with methotrexate and adalimumab (a tumor necrosis factor-alpha [TNF-α] inhibitor) for rheumatoid arthritis for 2 years, and he had also been treated with S-1 (tegafur, gimeracil, and oteracil potassium) for pancreatic metastasis of gastric cancer for 2 months. Regardless of the underlying pathologies, his general condition was good and he had worked as an electrician until 2 days before admission. However, his appetite had suddenly decreased from the day before admission, and high fever and hypoxia were also evident upon admission. A chest X-ray and computed tomography scan revealed left pleural effusion and consolidation in both lungs. The pneumonia severity index score was 165 and the risk class was V. Accordingly, we started to treat the pneumonia with a combination of levofloxacin and meropenem. Thereafter, we received positive urinary antigen test findings for Legionella pneumophila. After hospitalization, hypoxia was progressed and hypotension was emerged. Despite the application of appropriate antibiotics, vasopressors, and oxygenation, the patient died 8 h after admission. Even after his death, blood cultures were continued to consider the possibility of bacterial co-infection. Although no bacteria were detected from blood cultures, Gimenez staining revealed pink bacteria in blood culture fluids. Subsequent blood fluid culture in selective medium revealed L. pneumophila serogroup 1. Recently, TNF-α inhibitors have been described as a risk factor for Legionnaires' disease. In consideration of the increased frequency of TNF-α inhibitors, we may need to recognize anew that L. pneumophila might be a pathogen of severe community-acquired pneumonia. |
| 2012 | Function of adrenomedullin in inflammatory response of liver against LPS-induced endotoxemia. | APMIS | Adrenomedullin (AM) is a hypotension-causing peptide that was originally isolated from human pheochromocytoma cells, and it has been found to be expressed in various organs, including the liver. As the individual physiological and pathophysiological properties of AM peptide in the liver during endotoxemia in vivo has not yet been examined, we investigated this in experimental endotoxemia using heterozygote AM-deficient (AM(+/-)) mice. The AM concentration of AM(+/-) mice was significantly lesser than that of wild-type (WT) mice in lipopolysaccharide (LPS)-induced endotoxemia. After administering LPS, the survival rate for AM(+/-) mice was significantly lower than that for WT mice. Also, expressions of IL-1β mRNA, and TNF-α mRNA, and NF-κB p65 in the liver were markedly increased and serum ALT greatly elevated in comparison with WT mice. However, supplementation of exogenous AM reversed the deteriorations in mortality and inflammatory responses. Therefore, we conclude that AM plays an important role in regulating systemic inflammation and may be an important intrinsic factor for protecting against liver damage in LPS-induced endotoxemia. |
| 2013 | TNF-α blockade improves early post-resuscitation survival and hemodynamics in a swine model of ischemic ventricular fibrillation. | Resuscitation | Inflammatory cytokines have been implicated in the pathophysiology of post cardiac arrest syndrome, including myocardial dysfunction and hypotension, often leading to multi-organ system dysfunction and death. We hypothesized that administration of infliximab after return of spontaneous circulation (ROSC) would ameliorate hypotension and myocardial dysfunction and prolong survival.Domestic swine were anesthetized and instrumented. Balloon occlusion of the LAD coronary artery just distal to the first septal perforator was performed and VF followed spontaneously in all animals. After 7 min, chest compressions, defibrillation, and standard ACLS resuscitation was performed. Animals achieving ROSC (N=32) were randomized to receive infliximab (5 mg/kg, n=16) or vehicle (250 mL normal saline, n=16) immediately post-ROSC and survival and hemodynamics were monitored for 3 h.There were no differences in prearrest hemodynamic variables, TNF-α levels, or resuscitation variables between groups. Both groups demonstrated a time dependent decline in mean arterial pressure (MAP) and stroke work (SW) post-ROSC with a nadir at 1 h followed by recovery over hours 2 and 3. This decline was blunted in infliximab-treated swine (1-h between group difference in MAP 21 mm Hg, 95% CI 3-38 mm Hg and SW 6.7 gm-m, 95% CI 0.4-13 at 1 h). Left ventricular systolic dp/dt fell in the vehicle group (-437 mm Hg/s, 95% CI -183 to -690) but did not in the infliximab group. Tau rose only in the vehicle group (44 ms, 95% CI 1-87). Short-term survival was higher in the infliximab group (Kaplan-Meier p=0.022).Blockade of TNF-α in the immediate post-ROSC period improved survival and hemodynamic parameters in this swine model of ischemic VF. |
| 2012 | Melatonin reduces acute lung inflammation, edema, and hemorrhage in heatstroke rats. | Acta Pharmacol Sin | To assess the therapeutic effect of melatonin on heat-induced acute lung inflammation and injury in rats.Heatstroke was induced by exposing anesthetized rats to heat stress (36 °C, 100 min). Rats were treated with vehicle or melatonin (0.2, 1, 5 mg/kg) by intravenous administration 100 min after the initiatioin of heatstroke and were allowed to recover at room temperature (26 °C). The acute lung injury was quantified by morphological examination and by determination of the volume of pleural exudates, the number of polymorphonuclear (PMN) cells, and the myeloperoxidase (MPO) activity. The concentrations of tumor necrosis factor, interleukin (IL)-1β, IL-6, and IL-10 in bronchoalveolar fluid (BALF) were measured by ELISA. Nitric oxide (NO) level was determined by Griess method. The levels of glutamate and lactate-to-pyruvate ratio were analyzed by CMA600 microdialysis analyzer. The concentrations of hydroxyl radicals were measured by a procedure based on the hydroxylation of sodium salicylates leading to the production of 2,3-dihydroxybenzoic acid (DHBA).Melatonin (1 and 5 mg/kg) significantly (i) prolonged the survival time of heartstroke rats (117 and 186 min vs 59 min); (ii) attenuated heatstroke-induced hyperthermia and hypotension; (iii) attenuated acute lung injury, including edema, neutrophil infiltration, and hemorrhage scores; (iv) down-regulated exudate volume, BALF PMN cell number, and MPO activity; (v) decreased the BALF levels of lung inflammation response cytokines like TNF-alpha, interleukin (IL)-1β, and IL-6 but further increased the level of an anti-inflammatory cytokine IL-10; (vi) reduced BALF levels of glutamate, lactate-to-pyruvate ratio, NO, 2,3-DHBA, and lactate dehydrogenase.Melatonin may improve the outcome of heatstroke in rats by attenuating acute lung inflammation and injury. |
| 2012 | A Biohybrid Device for the Systemic Control of Acute Inflammation. | Disrupt Sci Technol | Properly regulated inflammation facilitates recognition and reaction to injury or infection, but inadequate or overly robust inflammation can lead to disease. Sepsis is an inflammatory disease that accounts for nearly 10% of total U.S. deaths, costing more than $17 billion. Acute inflammation in sepsis may evolve too rapidly to be modulated appropriately, and we suggest that therapies should focus not on abolishing inflammation, but rather on attenuating the positive feedback cycle of inflammation/damage/inflammation. In Gram-negative sepsis, bacterial endotoxin causes inflammation and is driven and regulated by the cytokine tumor necrosis factor-α (TNF-α), which is, in turn, negatively regulated via its endogenous inhibitor, soluble TNF-α receptor (). We generated stably gene-modified variants of human HepG2 hepatocytes, using lentiviral constructs coding for mouse sTNFR driven by the constitutive cytomegalovirus promoter, and seeded them in a scaled-down, experimental liver bioreactor. When connected to anesthetized, cannulated rats subjected to endotoxin infusion and maintained solely by the animals' circulation, this biohybrid device elevated circulating sTNFR, reduced the levels of TNF-α and other key inflammatory mediators, alleviated hypotension, and reduced circulating markers of organ damage. This novel class of biohybrid devices may bemodified for patient- and disease-specific application, and, thus, may represent a disruptive strategy that offers the potential for rational inflammation reprogramming. |
| 2013 | Temporary rapid bowel ligation as a damage control adjunct improves survival in a hypothermic traumatic shock swine model with multiple bowel perforations. | J Surg Res | Primary intestinal anastomosis is not the right choice for multiple bowel perforations under hemodynamically stable conditions. Our group has employed temporary rapid bowel ligation as a damage control procedure in a hypothermic traumatic shock swine model with multiple bowel perforations and hypothesized that damage control treatment would improve survival in the setting of a damage control surgery.The abdomen was shot one time with an experimental modified gun while pigs were hemorrhaged to a mean arterial pressure of 40 mm Hg and maintained in shock for 40 min. Cold lactated Ringer solution was gradually infused to induce hypothermia. Animals were randomized to control (no resuscitation), primary anastomosis (PA), or temporary rapid bowel ligation (damage control group, DC). Animals were resuscitated for 12 h with the shed blood and lactated Ringer solution. Delayed anastomosis was performed in DC animals after resuscitation. Surviving animals were humanely killed 24 h after operation. Systemic hemodynamic parameters were recorded and blood samples were obtained for biochemical assays. The lung and ileum was harvested at the end of the experiment for pathologic evaluation and test of wet/dry weight ratio, TNF-α level, and nuclear factor-κB activations.All animals suffered extreme physiologic conditions: hypothermia, severe acidosis, hypotension, and depressed cardiac output. Control animals suffered 100% mortality. Compared with the PA group, DC animals required less resuscitation fluid, normalized lactate levels faster, had lower serum creatine kinase, aspartate amino transferase levels and tissue TNF-α level and nuclear factor-κB activations, suffered less severe histopathology, had greater early survival.Multiple bowel perforations under hemodynamically stable conditions seem better managed with DC than with PA. Temporary rapid bowel ligation as a damage control adjunct is important to rapid control of multiple bowel perforations instead of a prolonged operative time. |
| 2011 | Glibenclamide reduces proinflammatory cytokines in an ex vivo model of human endotoxinaemia under hypoxaemic conditions. | Life Sci | In vivo application of the K(ATP)-channel blocker glibenclamide can reverse endotoxin-induced hypotension, vascular hyporeactivity and shock in experimental animals. The hypothesis of the present study is, that the drug effects might not only be based on direct inhibition of K(ATP)-channels of vascular smooth muscle cells, but might also reflect reduction of shock-induced excess proinflammatory cytokines and procoagulatory molecules produced in the blood monocytes.Human whole blood (normoxaemic or hypoxaemic) supplemented ex vivo with 100 ng/ml LPS was used to assess glibenclamide (3-100 μM) effects on IL-1 beta, IL-6, TNF-alpha, tissue factor, and plasminogen-activator-inhibitor-2 (PAI-2). Co-incubations with monocytes and erythrocytes and cytosolic calcium measurements were performed to reveal their purinergic intercellular interaction.In heparinized blood, glibenclamide reduced LPS-induced release of IL-1 beta and TNF-alpha, tissue factor and PAI-2 mRNA in a concentration-dependent manner. When samples were subjected to strong hypoxemia using 95% N(2)/5% CO(2), these parameters became even more sensitive to the drug. No drug effect was observable in citrated blood or in isolated monocytes. IL-1 beta mRNA inhibition by glibenclamide appeared to be dependent on P2X7-receptor activation of monocytes by ATP-releasing erythrocytes during hypoxia. Cytosolic calcium values as well as the duration of calcium transients elicited by P2X7-receptor stimulation in isolated monocytes were strongly increased during hypoxia, both of which could be abolished by glibenclamide.We conclude that the anti-inflammatory effect of glibenclamide is mainly based on the reduction of calcium entry by drug-induced depolarization of hypoxic monocytes. Thus, glibenclamide possesses a potentially beneficial shock-specific anti-inflammatory action. |
| 2011 | The role of renal hypoperfusion in development of renal microcirculatory dysfunction in endotoxemic rats. | Intensive Care Med | To study the role of renal hypoperfusion in development of renal microcirculatory dysfunction in endotoxemic rats.Rats were randomized into four groups: a sham group (n = 6), a lipopolysaccharide (LPS) group (n = 6), a group in which LPS administration was followed by immediate fluid resuscitation which prevented the drop of renal blood flow (EARLY group) (n = 6), and a group in which LPS administration was followed by delayed (i.e., a 2-h delay) fluid resuscitation (LATE group) (n = 6). Renal blood flow was measured using a transit-time ultrasound flow probe. Microvascular perfusion and oxygenation distributions in the renal cortex were assessed using laser speckle imaging and phosphorimetry, respectively. Interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α were measured as markers of systemic inflammation. Furthermore, renal tissue samples were stained for leukocyte infiltration and inducible nitric oxide synthase (iNOS) expression in the kidney.LPS infusion worsened both microvascular perfusion and oxygenation distributions. Fluid resuscitation improved perfusion histograms but not oxygenation histograms. Improvement of microvascular perfusion was more pronounced in the EARLY group compared with the LATE group. Serum cytokine levels decreased in the resuscitated groups, with no difference between the EARLY and LATE groups. However, iNOS expression and leukocyte infiltration in glomeruli were lower in the EARLY group compared with the LATE group.In our model, prevention of endotoxemia-induced systemic hypotension by immediate fluid resuscitation (EARLY group) did not prevent systemic inflammatory activation (IL-6, IL-10, TNF-α) but did reduce renal inflammation (iNOS expression and glomerular leukocyte infiltration). However, it could not prevent reduced renal microvascular oxygenation. |
| 2011 | Immunosensory signalling by carotid body chemoreceptors. | Respir Physiol Neurobiol | Injections of lipopolysaccharide (LPS) have been used to produce the signs of sepsis and study their underlying mechanisms. Intravenous (IV) injections of LPS in anesthetized cats induce tachypnea, tachycardia and hypotension, but ventilatory changes are suppressed after sectioning carotid and aortic nerves. Otherwise, LPS increases the basal frequency of carotid chemosensory discharges, but reduces ventilatory and chemosensory responses to hypoxia and nicotine injections. Increases in cytokines (IL-1β, IL-6 and TNF-α) are observed in plasma and tissues after injecting LPS. In carotid bodies perfused in vitro, TNF-α reduces chemosensory discharges induced by hypoxia. The rat carotid body and its sensory ganglion constitutively express LPS canonical receptor, TLR4, as well as TNF-α and its receptors (TNF-R1 and TNF-R2). Increases of TNF-α and TNF-R2 expression occur after LPS administration. The activation of peripheral and central autonomic pathways induced by LPS or IL's is partly dependent on intact vagus nerves. Thus, the carotid and vagus nerves provide routes between the immune system and CNS structures involved in systemic inflammatory responses. |
| 2011 | Early potassium channel blockade improves sepsis-induced organ damage and cardiovascular dysfunction. | Br J Pharmacol | There is increasing evidence that potassium channels are involved in the cardiovascular dysfunction of sepsis. This evidence was obtained after the systemic inflammation, cardiovascular dysfunction and organ damage had developed. Here we have studied the consequences of early interference with potassium channels on development of sepsis.Sepsis was induced by caecal ligation and puncture (CLP) or sham surgery in Wistar rats. Four hours after surgery, animals received tetraethylammonium (TEA; a non-selective potassium channel blocker) or glibenclamide (a selective ATP-sensitive potassium channel blocker). Twenty-four hours after surgery, inflammatory, biochemical, haemodynamic parameters and survival were evaluated.Sepsis significantly increased plasma NO(x) levels, expression of inducible nitric oxide synthase (NOS-2) protein in lung and thigh skeletal muscle, lung myeloperoxidase, urea, creatinine and lactate levels, TNF-α and IL-1β, hypotension and hyporesponsiveness to phenylephrine and hyperglycemia followed by hypoglycemia. TEA injected 4 h after surgery attenuated the increased NOS-2 expression, reduced plasma NO(x) , lung myeloperoxidase activity, levels of TNF-α and IL-1β, urea, creatinine and lactate levels, prevented development of hypotension and hyporesponsiveness to phenylephrine, the alterations in plasma glucose and reduced late mortality by 50%. Glibenclamide did not improve any of the measured parameters and increased mortality rate, probably due to worsening the hypoglycemic phase of sepsis.Early blockade of TEA-sensitive (but not the ATP-sensitive subtype) potassium channels reduced organ damage and mortality in experimental sepsis. This beneficial effect seems to be, at least in part, due to reduction in NOS-2 expression. |
| 2011 | Use of enterally delivered angiotensin II type Ia receptor antagonists to reduce the severity of colitis. | Dig Dis Sci | Renin-angiotensin system blockade reduces inflammation in several organ systems. Having found a fourfold increase in angiotensin II type Ia receptor expression in a dextran sodium sulfate colitis model, we targeted blockade with angiotensin II type Ia receptor antagonists to prevent colitis development. Because hypotension is a major complication of angiotensin II type Ia receptor antagonists use, we hypothesized that use of angiotensin II type Ia receptor antagonists compounds which lack cell membrane permeability, and thus enteric absorption, would allow for direct enteral delivery at far higher concentrations than would be tolerated systemically, yet retain efficacy.Based on the structure of the angiotensin II type Ia receptor antagonist losartan, deschloro-losartan was synthesized, which has extremely poor cell membrane permeability. Angiotensin II type Ia receptor antagonist efficacy was evaluated by determining the ability to block NF-κB activation in vitro. Dextran sodium sulfate colitis was induced in mice and angiotensin II type Ia receptor antagonist efficacy delivered transanally was assessed.In vitro, deschloro-losartan demonstrated near equal angiotensin II type Ia receptor blockade compared to losartan as well as another angiotensin II type Ia receptor antagonist, candesartan. In the dextran sodium sulfate model, each compound significantly improved clinical and histologic scores and epithelial cell apoptosis. Abundance of TNF-α, IL-1β, and IL6 mRNA were significantly decreased with each compound. In vitro and in vivo intestinal drug absorption, as well as measures of blood pressure and mucosal and colonic blood flow, showed significantly lower uptake of deschloro-losartan compared to losartan and candesartan.This study demonstrated efficacy of high-dose angiotensin II type Ia receptor antagonists in this colitis model. We postulate that a specially designed angiotensin II type Ia receptor antagonist with poor oral absorption may have great potential as a new therapeutic agent for inflammatory bowel disease in the future. |
| 2011 | Comparing hemodynamics, blood gas analyses and proinflammatory cytokines in endotoxemic and severely septic rats. | Int Immunopharmacol | Lipopolysaccharide (LPS) is often used in short-term models of inflammation. Since endotoxemia and sepsis are different entities we have recently established a short-term sepsis model in rats induced by cecal ligation and incision (CLI). This retrospective study was conducted in order to identify similarities and differences between both experimental approaches. 32 anesthetized/ventilated male rats from the following four groups were analysed (each n=8): CTRL-group (0.9% NaCl i.v.); LPS-group (5mg/kg i.v.); SHAM-group (laparotomy); CLI-group (1.5 cm blade incision). Mean arterial blood pressure (MAP) and blood gas parameters (arterial base excess (BE) and pH) were continuously recorded. Total observation time was 300 min. Plasma samples were obtained afterwards. LPS and CLI induced significant arterial hypotension and metabolic acidosis compared to CTRL- or SHAM-group, respectively. Yet, between the LPS- and CLI-groups, there were no differences in MAP, BE and pH. LPS significantly induced IL-1β, IL-6 and TNF-α in the plasma. In contrast, CLI showed a clear tendency towards increased IL-1β and IL-6 plasma levels and did not affect TNF-α. Our results indicate that the CLI sepsis model is suitable for short-term investigations on hemodynamic alterations and blood gas analyses during sepsis. 300 min after the proinflammatory insult, plasma concentrations of IL-1β and IL-6 in the plasma remain considerably lower after CLI compared to endotoxemia. Low TNF-α concentrations 300 min after sepsis induction could be interpreted as considerable immunosuppression during CLI sepsis. |
| 2011 | Kynurenic acid attenuates multiorgan dysfunction in rats after heatstroke. | Acta Pharmacol Sin | To assess whether systemic delivery of kynurenic acid improves the outcomes of heatstroke in rats.Anesthetized rats were divided into 2 major groups and given vehicle solution (isotonic saline 0.3 mL/kg rat weight) or kynurenic acid (30-100 mg in 0.3 mL saline/kg) 4 h before the start of thermal experiments. They were exposed to an ambient temperature of 43 °C for 68 min to induce heatstroke. Another group of rats were exposed to room temperature (26 °C) and used as normothermic controls. Their core temperatures, mean arterial pressures, serum levels of systemic inflammatory response molecules, hypothalamic values of apoptotic cells and neuronal damage scores, and spleen, liver, kidney and lung values of apoptotic cells were determined.The survival time values during heatstroke for vehicle-treated rats were decreased from the control values of 475-485 min to new values of 83-95 min. Treatment with KYNA (30-100 mg/kg, iv) 4 h before the start of heat stress significantly and dose-dependently decreased the survival time to new values of 152-356 min (P<0.05). Vehicle-treated heatstroke rats displayed hypotension, hypothalamic neuronal degeneration and apoptosis, increased serum levels of tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and interleukin-10 (IL-10), and spleen, liver, kidney, and lung apoptosis. KYNA preconditioning protected against hypotension but not hyperthermia and attenuated hypothalamic neuronal degeneration and apoptosis during heatstroke. KYNA preconditioning attenuated spleen, kidney, liver, and lung apoptosis and up-regulated serum IL-10 levels but down-regulated serum TNF-α and ICAM-1 levels during heatstroke.Our results suggest that systemic delivery of kynurenic acid may attenuate multiorgan dysfunction in rats after heatstroke. |
| 2010 | Endothelin receptor antagonist attenuates inflammatory response and prolongs the survival time in a neonatal sepsis model. | Intensive Care Med | To evaluate effects of endothelin receptor antagonist ETR-P1/fl in a neonatal sepsis model.Eighteen anesthetized and mechanically ventilated 3-day-old piglets were divided into three groups. Six piglets received cecal ligation and perforation (CLP group). Six piglets were administrated a continuous infusion of ETR-P1/fl (0.05 mg/kg/h), an antisense homology box-derived peptide with an endothelin A receptor antagonist effect, starting 30 min after CLP (ETR-P1/fl group). Six piglets acted as the sham group. Mean arterial pressure (MAP), heart rate, cardiac output, arterial blood gas, body temp (BT), serum nitrite and nitrate (NOx), tumor necrosis factor (TNF)-α, and high-mobility group box 1 (HMGB-1) were measured before CLP and at 1, 3, 6, and 9 h after CLP.Cecal ligation and perforation exposure evoked a state of shock and showed deteriorated cardiac output, pulmonary hypertension, decreased MAP, low oxygen saturation, and base excess (BE) with elevated TNF-α, NOx, and HMGB1. ETR-P1/fl administration resulted in higher MAP at 6 and 9 h after CLP, less negative BE, lower mean pulmonary arterial pressure (mPAP)/MAP ratio at 9 h after CLP, and lower TNF-α, NOx, and HMGB-1 compared to the CLP group. BT showed no differences between the groups. Survival time in the ETR-P1/fl group was longer than in the CLP group (18.9 ± 2.3 h vs. 9.0 ± 0.8 h, p < 0.01).ETR-P1/fl treatment significantly attenuated the elevation of NOx, TNF-α, and HMGB-1, which improved the systemic hypotension, pulmonary hypertension, and blood gases, thereby causing improvement of survival time in a progressive neonatal sepsis CLP model. |
| 2010 | Effects of combination treatment with dexamethasone and mannitol on neuronal damage and survival in experimental heat stroke. | Biol Pharm Bull | There is evidence that increased plasma cytokines, elevated brain levels of monoamines and hydroxyl radical production may be implicated in pathogenesis during heat stroke in rats. Acute treatment with a combined therapeutic approach has been repeatedly advocated in cerebral ischemia experiments. The aim of this study was to investigate whether the combined agent (mannitol and dexamethasone) has beneficial efficacy to improve the survival time (ST) and heat stroke-induced damage in experimental heat stroke. Urethane-anesthetized rats underwent instrumentation for the measurement of colonic temperature, mean arterial pressure (MAP), striatal cerebral blood flow (CBF), heart rate, and neuronal damage score. The rats were exposed to an ambient temperature (43 degrees C) to induce heat stroke. Concentrations of the ischemic and damage markers, dopamine, serotonin, and hydroxyl radical production in corpus striatum, and the plasma levels of tumor necrosis factor-alpha (TNF-alpha) were observed during heat stroke. After the onset of heat stroke, the heat stroke rats display decreased MAP, decreased CBF, increased the plasma levels of TNF-alpha, increased cerebral striatal monoamines and hydroxyl radical production release, and severe cerebral ischemia and neuronal damage compared with those of normothermic control rats. However, immediate treatment with the combined agent confers significant protection against heat stroke-induced arterial hypotension, systemic inflammation, cerebral ischemia, cerebral monoamines and hydroxyl radical production overloads, and improves neuronal damage and the ST in heat stroke rats. Our data suggest that administration of this combined agent seems to have more effective to ameliorate the heat stroke-induced neuronal damage and prolong the ST. |
| 2010 | The hemodynamics of human septic shock relate to circulating innate immunity factors. | Immunol Invest | The role of innate immunity, e.g., complement activation and cytokine release in the hemodynamic alterations in the course of human septic shock is largely unknown. We prospectively studied 14 consecutive septic shock patients with a pulmonary artery catheter in place. For 3 days after admission, hemodynamic variables and plasma levels of C3a, a product of complement activation, and interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) were measured 6-hourly. Doses of vasoactive drugs were recorded. Of the 14 patients, 8 died in the ICU. Patients had a hyperdynamic circulation with tachycardia, mild hypotension, increased cardiac index, peripheral vasodilation and myocardial depression. C3a, IL-6 and TNF-α plasma levels were supranormal in 123 of 138 (89%), 132 of 138 (96%) and 83 of 111 (75%) measurements, respectively. Independently of blood culture results, treatment with vasoactive drugs and outcome, mean arterial blood pressure and systemic vascular resistance index were lower when IL-6 levels were higher and left ventricular function was less depressed when C3a levels were higher in the course of septic shock. The TNF-α levels did not invariably relate to peripheral vascular and myocardial function parameters. Our serial observations suggest that, in human septic shock, peripheral vasodilation is most strongly and independently, of all inflammatory factors, associated with IL-6 release, whereas complement activation partly offsets the myocardial depression of the syndrome. Innate immunity factors may thus differ in their contribution to the course of hemodynamic abnormalities of septic shock. |
| 2010 | Spectrum of sepsis, mediators, source control and management of bundles. | Front Biosci (Elite Ed) | Sepsis is a modern medicine icon and the onset of organ dysfunction is one of the worst scenario. More than 100 distinct molecules have been proposed as useful biological markers of sepsis. TNF-alpha, IL-6, chemokines and cytokines are considered the first line factors able to drive the dynamic process of sepsis. The PIRO scheme is a new classification of different aspects, used to stage sepsis. Resuscitation bundles must be started within 6 hours of presentation (serum lactate measured; blood cultures obtained before antibiotic therapy; broad-spectrum antibiotics within 3 hours from emergency admission and 1 hour from ICU admission; in case of hypotension and/or lactate higher than 4 mmol/L deliver an initial 20 ml/kg of crystalloid or colloid solution or apply vasopressors for hypotension not responding to initial fluid resuscitation to maintain mean arterial pressure above 65 mmHg). A management bundle should be implemented within 24 hour (low-dose steroids administered for septic shock; recombinant human activated protein C; glucose control maintained at less than 8.3 mmol/L; inspiratory plateau pressures maintained at less than 30 cm H2O). |
| 2010 | Reactive oxygen species and small-conductance calcium-dependent potassium channels are key mediators of inflammation-induced hypotension and shock. | J Mol Med (Berl) | Septic shock is associated with life-threatening vasodilation and hypotension. To cause vasodilation, vascular endothelium may release nitric oxide (NO), prostacyclin (PGI2), and the elusive endothelium-derived hyperpolarizing factor (EDHF). Although NO is critical in controlling vascular tone, inhibiting NO in septic shock does not improve outcome, on the contrary, precipitating the search for alternative therapeutic targets. Using a hyperacute tumor necrosis factor (TNF)-induced shock model in mice, we found that shock can develop independently of the known vasodilators NO, cGMP, PGI2, or epoxyeicosatrienoic acids. However, the antioxidant tempol efficiently prevented hypotension, bradycardia, hypothermia, and mortality, indicating the decisive involvement of reactive oxygen species (ROS) in these phenomena. Also, in classical TNF or lipopolysaccharide-induced shock models, tempol protected significantly. Experiments with (cell-permeable) superoxide dismutase or catalase, N-acetylcysteine and apocynin suggest that the ROS-dependent shock depends on intracellular (*)OH radicals. Potassium channels activated by ATP (K(ATP)) or calcium (K(Ca)) are important mediators of vascular relaxation. While NO and PGI2-induced vasodilation involves K(ATP) and large-conductance BK(Ca) channels, small-conductance SK(Ca) channels mediate vasodilation induced by EDHF. Interestingly, also SK(Ca) inhibition completely prevented the ROS-dependent shock. Our data thus indicate that intracellular (*)OH and SK(Ca) channels represent interesting new therapeutic targets for inflammatory shock. Moreover, they may also explain why antioxidants other than tempol fail to provide survival benefit during shock. |
| 2010 | Cytokine adsorbing columns. | Contrib Nephrol | Sepsis induces the activation of complement and the release of inflammatory cytokines such as TNF-alpha and IL-1beta. The inflammatory cytokines and nitric oxide induced by sepsis can decrease systemic vascular resistance, resulting in profound hypotension. The combination of hypotension and microvascular occlusion results in tissue ischemia and ultimately leads to multiple organ failure. Recently, several experimental and clinical studies have reported that treatment for adsorption of cytokines is beneficial during endotoxemia and sepsis. Therefore, the present article discusses cytokine adsorbing columns. These columns, such as CytoSorb, CYT-860-DHP, Lixelle, CTR-001 and MPCF-X, the structures of which vary significantly, have excellent adsorption rates for inflammatory cytokines such as TNF-alpha, IL-1beta, IL-6 and IL8. Many studies have demonstrated that treatment with cytokine adsorbing columns has beneficial effects on the survival rate and inflammatory responses in animal septic models. Moreover, several cases have been reported in which treatment with cytokine adsorbing columns is very effective in hemodynamics and organ failures in critically ill patients. Although further investigations and clinical trials are needed, in the future treatment with cytokine adsorbing columns may play a major role in the treatment of hypercytokinemia such as multiple organ failure and acute respiratory distress syndrome. |
| 2010 | Preclinical investigation of PEGylated tumor necrosis factor alpha in dogs with spontaneous tumors: phase I evaluation. | Clin Cancer Res | Tumor necrosis factor-alpha (TNF) is a cytokine with potent antitumor activity; however, toxicity and short half-life have limited its utility. Polyethylene glycol (PEG) conjugation of biotherapeutics can decrease immunogenicity while improving bioactivity and half-life. PEGylation of TNF (PEG-TNF) significantly improved half-life and toxicity in mice, resulting in enhanced antitumor activity. This study characterized toxicity, biological effect, and antitumor activity of PEG-TNF in pet dogs with spontaneous cancer.A phase I clinical trial enrolled dogs with measurable tumors in which standard therapy had failed or been declined. Physiologic, hematologic, and biochemical parameters were evaluated and tumor biopsies obtained serially. A subset of patients underwent serial dynamic contrast-enhanced magnetic resonance imaging.Fifteen dogs were enrolled at doses from 20.0 to 30.0 microg/kg. Dose-limiting toxicity at 30.0 microg/kg consisted of vascular leak in one and hypotension/coagulopathy in one, establishing 26.7 microg/kg as the maximum tolerated dose. Mean elimination half-life was 15.3 +/- 4.9 hours. Biological activity (transient fever and leukopenia, increased tumor inflammation, and necrosis) was observed at all dosages. A significant increase in tumor blood flow was observed with dynamic contrast-enhanced magnetic resonance imaging. Minor/transient antitumor responses were observed in dogs with melanoma, squamous cell carcinoma, and mammary carcinoma, and a partial response was observed in a dog with angiosarcoma.Using a clinically relevant, spontaneous large animal model of neoplasia, we have shown that biologically effective doses of PEG-TNF can be administered safely, and that PEG-TNF administration is associated with encouraging biological activity. These results justify the clinical evaluation of PEG-TNF in human cancer. |
| 2010 | Anticonvulsive effects of the dopamine agonist lisuride maleate after experimental traumatic brain injury. | Neurosci Lett | Traumatic brain injury is a heterogeneous disease, encompassing a wide range of pathologies. The dopamine agonist lisuride is well established in the therapy of Parkinson's disease. Additionally to its dopaminergic effects it decreases prolactine release, reducing the amount of inflammatory mediators such as TNF-alpha or Il-6. Lisuride has strong binding affinity to serotonergic and histaminergic receptors on neuronal and glial cells leading to scavenging of highly reactive free radicals. Due to its interaction with dopaminergic D2 and D4 receptors as well as 5-HT-1A receptors, NMDA-receptor signaling and glutamate-mediated excitotoxicity can be modulated beneficially. Despite of these promising neuroprotective effects, experimental data scrutinizing the effects of lisuride after acute brain injury are sparse. We therefore investigated the effect of lisuride after controlled cortical impact injury (CCII) in rats. 70 male Sprague-Dawley rats were randomized to lisuride or to placebo treatment by an initial s.c. loading dose (0.3mg/kg BW) and following continuous application (0.5mg/kg/d) by s.c. implanted osmotic pumps. In three experimental groups we determined (sub)acute neuro-physiological changes after trauma. Mean arterial blood pressure, intracranial pressure, and electrical brain activity were monitored acutely for up to 3h after trauma. Brain edema formation was assessed 24h after CCII. Furthermore, contusion volumes were quantified by magnetic resonance tomography and neurological testing was performed for up to 7 days after injury. Associated with the administration of lisuride there was a significant reduction in duration and number of post-traumatic seizures. Despite of a sustained arterial hypotension following the initial bolus administration in the treatment group, contusion volumes and neurological function tests did not differ significantly in comparison to the control group. Overall, lisuride seems to have significant anticonvulsive effects but seems not to influence secondary brain damage in this experimental model. |
| Cool temperature hemodialysis and biocompatibility in chronic hemodialysis patients: a preliminary study. | J Nephrol | Cooler temperature dialysate (TD) has gained in popularity in the treatment of hypotension during hemodialysis (HD). In this study we verified the hypothesis of an eventual involvement of cytokines.Four patients on regular HD underwent two 4-hour HD sessions once at 37 degrees C TD and once at 35 degrees C TD. The concentration of the cytokines (cyt) IL-1, IL-2, IL-8, IL-12 and tumor necrosis factor-alpha (TNF-alpha) was measured before the HD session initiation and after 20, 60, 120 and 240 minutes. Body temperature, weight, blood pressure and heart rate were registered at the same time points.We found a higher blood pressure at 35 degrees C but no intradialytic differences in cyt concentration at 35 degrees C or 37 degrees C. The percentage changes of cyt from baseline were very slight, except for IL-8 which decreased by 40% both at 35 degrees C and 37 degrees C.These preliminary results suggest that cytokines do not seem play a relevant role in determining the favorable effects of cooler TD on blood pressure. Our study is preliminary and our results need to be confirmed by other studies. |
| 2011 | Effects of ethyl pyruvate and other α-keto carboxylic acid derivatives in a rat model of multivisceral ischemia and reperfusion. | J Surg Res | Ethyl pyruvate (EP) has been shown to ameliorate hepatic, renal, and intestinal mucosal injury and down-regulate expression of several pro-inflammatory mediators in a wide variety of preclinical models of critical illnesses, such as sepsis, burn injury, acute pancreatitis, stroke, and hemorrhagic shock. The molecular mechanisms responsible for the therapeutic effects of EP remain poorly understood, but might be related to the compound's structure as the ester of an α-keto carboxylic acid. Herein, we tested the hypothesis that EP and other α-keto carboxylic acid derivatives can modulate organ injury after lower torso ischemia/reperfusion (I/R).Rats were subjected to 50 min of supraceliac aortic occlusion. Over a 20-min period, starting 2 min before the release of the aortic clamp, the animals received 2 μL/g of Ringer's lactate solution (RL, n = 5) or an equivalent volume of a solution containing EP (n = 5), benzoyl formate (BF, n = 5), parahydroxyphenyl pyruvate (PHPP, n = 5) or sodium pyruvate (NaPyr, n = 5). The total dose of each compound was 0.86 mMol/kg. After 1h of reperfusion, we measured ileal mucosal permeability to fluorescein-labeled dextran (mw 4000 Da), liver malondialdehyde (MDA) content, and plasma levels of alanine aminotransferase (ALT) and TNF. Rats in the control group (CT, n = 4) were subjected to laparotomy and surgical isolation of the supraceliac aorta, but not visceral I/R.Ileal mucosal permeability, plasma levels of ALT and TNF, and hepatic MDA content increased significantly in the RL group relative to the CT group. Both EP and BF significantly ameliorated the development of systemic arterial hypotension, mucosal hyperpermeability, and significantly decreased plasma levels of TNF. MDA content was significantly decreased by EP, PHPP, BF, and NaPyr.In general, EP is more efficacious in this model than is NaPyr. Although more remains to be learned about the pharmacologic differences between EP and pyruvate, one important factor may the greater lipophilicity of the former compound. This insight may permit the development of even more effective cytoprotective and anti-inflammatory agents based on the pyruvoyl moiety. |
| 2009 | Isoflurane preconditioning ameliorates endotoxin-induced acute lung injury and mortality in rats. | Anesth Analg | The effects of isoflurane pretreatment on pulmonary proinflammatory cytokines and survival in severe endotoxin-induced acute lung injury (ALI) have not been studied systemically. We investigated the effect of preadministration of isoflurane on ALI induced by lipopolysaccharide (LPS) in rats.Male Sprague-Dawley rats weighing 250-300 g were randomly assigned to 1 of 4 groups: sham rats (injected intraperitoneally [IP] with saline) pretreated with vehicle (100% O(2)) (sham-vehicle); sham rats pretreated with isoflurane (sham-ISO); LPS rats (injected IP with LPS) pretreated with vehicle (vehicle-LPS); and LPS rats pretreated with isoflurane (ISO-LPS). Endotoxemia was induced by IP injection of LPS. Isoflurane 1.4% was administered 30 min before LPS injection. The animals were then observed for 6 h. We monitored arterial blood pressure, heart rate, and blood gas. The extent of ALI was evaluated by lung wet/dry ratio, Evans blue dye extravasation, and histologic examination. We also measured pulmonary nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 levels. In addition, survival statistics and pulmonary inducible NO synthase (iNOS) gene expression were also determined.LPS caused systemic hypotension and severe ALI, as evidenced by the increases in the extent of ALI, impairment of pulmonary functions, and increases in pulmonary NO, TNF-alpha, IL-1beta, and IL-6. Isoflurane preconditioning mitigated systemic hypotension and the development of ALI. Isoflurane preconditioning also attenuated the LPS-induced increases in pulmonary nitrate/nitrite and proinflammatory cytokine release and improved survival of rats with severe sepsis. The expression of iNOS was upregulated by LPS and reduced by isoflurane pretreatment.Isoflurane preconditioning can attenuate pulmonary proinflammatory cytokine release and decrease the mortality induced by severe sepsis. Early protection seems to be mediated partly through inhibition of iNOS-NO pathway activation. |
| 2010 | Inhibition of NF-kappaB ameliorates sepsis-induced downregulation of aquaporin-2/V2 receptor expression and acute renal failure in vivo. | Am J Physiol Renal Physiol | Acute renal failure (ARF) is frequently associated with polyuria and urine concentration defects and it is a severe complication of sepsis because it increases the mortality rate. Inhibition of NF-kappaB activation has been suggested to provide a useful strategy for the treatment of septic shock. However, the impact on sepsis-induced ARF is still unclear. Therefore, we examined the effect of pyrrolidine dithiocarbamate (PDTC) and of small interfering RNA (siRNA) silencing NF-kappaB p50/p105 on sepsis-induced downregulation of vasopressin V(2) receptors and aquaporin (AQP)-2 channels using a cecal ligation and puncture (CLP) mouse model. CLP caused a time-dependent downregulation of renal vasopressin V(2) receptor and of AQP2 expression without alterations in plasma vasopressin levels. Renal activation of NF-kappaB in response to CLP was attenuated by PDTC pretreatment, which also attenuated the downregulation of V(2) receptor and AQP2 expression. Furthermore, a strong nuclear staining for the NF-kappaB p50 subunit throughout the whole kidney in response to CLP was observed. siRNA against NF-kappaB p50 attenuated the CLP-induced nuclear translocation of the p50 subunit and the CLP-induced downregulation of V(2) receptor and AQP2 expression. Additionally, PDTC and siRNA pretreatment inhibited the CLP-induced increase in renal TNF-alpha and IL-1beta concentration and NOS-2 mRNA abundance. Moreover, PDTC and siRNA pretreatment ameliorated CLP-induced hypotension and ARF. Our findings suggest that NF-kappaB activation is of importance for the downregulation of AQP2 channel and vasopressin V(2) receptor expression during sepsis. In addition, our data indicate that NF-kappaB inhibition ameliorates sepsis-induced ARF. |
| 2009 | Elevated serum cytokines during human anaphylaxis: Identification of potential mediators of acute allergic reactions. | J Allergy Clin Immunol | Anaphylaxis is generally unanticipated and requires emergency management. Therefore, the biological mediators in human beings have been difficult to define.Our aim was to identify cytokines and chemokines whose concentrations increase during anaphylaxis in human beings and to determine how each correlates with severity.We measured the concentrations of potential mediators, including cytokines, chemokines, mast cell tryptase (MCT), and histamine, over 3 time points in 76 patients presenting to emergency departments with anaphylaxis and correlated these with a global severity scale, hypotension, and hypoxia.IL-2, IL-6, IL-10, TNF receptor I, MCT, and histamine were significantly elevated in patients with severe reactions (n = 36) compared with moderate reactions (n = 40) and healthy controls. Histamine levels peaked at emergency department arrival, whereas other mediators peaked later. IL-4, IL-5, IL-13, IFN-gamma, and TNF-alpha were marginally elevated in severe reactions compared with healthy controls but did not correlate with reaction severity. Severe reactions tended to be either hypotensive (n = 19) or hypoxemic (n = 12). Levels of IL-6, IL-10, TNF receptor I, MCT, and histamine correlated with hypotension. No mediator correlated with hypoxemia or other respiratory features.This study confirms that the concentrations of a number of cytokines are elevated in blood during anaphylaxis in human beings and that some correlate with the presence of hypotension. Others were only marginally elevated within a concentration range that available assays do not reliably detect. During respiratory reactions, mediators may be largely confined to the airways so that blood concentrations do not reflect activity. |
| 2009 | A pivotal role of endothelial-specific NF-kappaB signaling in the pathogenesis of septic shock and septic vascular dysfunction. | J Immunol | Although the role of NF-kappaB in the pathogenesis of sepsis and septic shock has been extensively studied, little is known about the causative contribution of endothelial-intrinsic NF-kappaB to these pathological processes. In this study, we used transgenic (TG) mice (on FVB genetic background) that conditionally overexpress the NF-kappaB inhibitor, mutant I-kappaBalpha, selectively on endothelium and their transgene-negative littermates (wild type (WT)) to define the causative role of endothelial-specific NF-kappaB signaling in septic shock and septic vascular dysfunction. In WT mice, LPS challenge caused systemic hypotension, a significantly blunted vasoconstrictor response to norepinephrine, and an impaired endothelium-dependent vasodilator response to acetylcholine, concomitant with a markedly increased aortic inducible NO synthase expression, significantly elevated plasma and aortic levels of nitrite/nitrate, increased aortic TNF-alpha expression, and decreased aortic endothelial NO synthase (eNOS) expression. In TG mice whose endothelial NF-kappaB was selectively blocked, LPS caused significantly less hypotension and no impairments in vasoconstrictor and endothelium-dependent vasodilator responses, associated with significantly reduced aortic inducible NO synthase expression, decreased plasma and aortic levels of nitrite/nitrate, reduced aortic TNF-alpha expression, and increased aortic eNOS expression. TNF-alpha knockout mice prevented LPS-induced eNOS down-regulation. WT mice subjected to cecal ligation and puncture showed significant systemic hypotension, which was prevented in TG mice. Our data show that selective blockade of endothelial-intrinsic NF-kappaB pathway is sufficient to abrogate the cascades of molecular events that lead to septic shock and septic vascular dysfunction, demonstrating a pivotal role of endothelial-specific NF-kappaB signaling in the pathogenesis of septic shock and septic vascular dysfunction. |
| 2009 | The novel role of platelet-activating factor in protecting mice against lipopolysaccharide-induced endotoxic shock. | PLoS One | Platelet-activating factor (PAF) has been long believed to be associated with many pathophysiological processes during septic shock. Here we present novel activities for PAF in protecting mice against LPS-mediated endotoxic shock.In vivo PAF treatment immediately after LPS challenge markedly improved the survival rate against mortality from endotoxic shock. Administration of PAF prominently attenuated LPS-induced organ injury, including profound hypotension, excessive polymorphonuclear neutrophil infiltration, and severe multiple organ failure. In addition, PAF treatment protects against LPS-induced lymphocytes apoptosis. These protective effects of PAF was correlated with significantly decreases in the production of the inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, and IFN-gamma, while increasing production of the anti-inflammatory cytokine IL-10 in vivo and in vitro.Taken together, these results suggest that PAF may protect mice against endotoxic shock via a complex mechanism involving modulation of inflammatory and anti-inflammatory mediators. |
| Correlation between atopy and hypersensitivity reactions during therapy with three different TNF-alpha blocking agents in rheumatoid arthritis. | Clin Exp Rheumatol | The use of TNF-alpha antagon-ists (infliximab, etanercept, adalimumab) has changed the course of many rheumatic diseases including rheumatoid arthritis (RA). Since their approval, some questions regarding their safety have been raised. Both acute and delayed reactions have been described.The aim of our work was to detect if there is a different incidence of hypersensitivity reactions - infusion reactions to infliximab or injection site reactions with etanercept or adalimumab - in atopic patients versus non- atopic patients. In 90 patients (82 females, 8 males) with rheumatoid arthritis we evaluated, during the first year of therapy with three different TNF-alpha blocking agents, total serum IgE (normal value <100 KU/L) (method ImmunoCAP PHADIA) and serum specific IgE performing a qualitative multi-allergen test for inhal-ant allergens (PHADIATOP, method ImmunoCAP PHADIA). In all patients we evaluated injection site reactions (ISR) to etanercept and adalimumab - erythema, edema and itching at the site of subcutaneous administration - and infusion reactions to infliximab - hypotension/hypertension, chest pain, dyspnea, laryngospasm, fever, urticaria angioedema.We obtained the following results: patients with high value of tot-al IgE were 15/90 (16.6 %), patients with total IgE in normal range were 75/90 (83.4.%), reactions in patients with high total IgE were 6.7% and in patients with normal total IgE were 18.7% (p=0.255 ns). As regards serum specific IgE, patients with specific IgE were 17/90 (18.8%) patients without specific IgE were 73/90 (81.2%), reactions in patients with specific IgE were 11.8% and in patients without specific IgE were 17.8% (p=0.547 ns). Also, when the data were divided for the three groups, the differences were not statistically significant.Adverse reactions to biological agents have been categorized into five types. In hypersensitivity reactions - the Beta type reactions - an immune mechanism is suspected. Our data showed that there was no correlation between the atopic status and the incidence of hypersensitivity reactions during the first year of therapy with three different TNF-alpha blocking agents. |
| 2009 | GYY4137, a novel hydrogen sulfide-releasing molecule, protects against endotoxic shock in the rat. | Free Radic Biol Med | GYY4137 (morpholin-4-ium-4-methoxyphenyl(morpholino) phosphinodithioate) is a slow-releasing hydrogen sulfide (H(2)S) donor. Administration of GYY4137 (50 mg/kg, iv) to anesthetized rats 10 min after lipopolysaccharide (LPS; 4 mg/kg, iv) decreased the slowly developing hypotension. GYY4137 inhibited LPS-induced TNF-alpha production in rat blood and reduced the LPS-evoked rise in NF-kappaB activation, inducible nitric oxide synthase/cyclooxygenase-2 expression, and generation of PGE(2) and nitrate/nitrite in RAW 264.7 macrophages. GYY4137 (50 mg/kg, ip) administered to conscious rats 1 or 2 h after (but not 1 h before) LPS decreased the subsequent (4 h) rise in plasma proinflammatory cytokines (TNF-alpha, IL-1beta, IL-6), nitrite/nitrate, C-reactive protein, and L-selectin. GYY4137 administration also decreased the LPS-evoked increase in lung myeloperoxidase activity, increased plasma concentration of the anti-inflammatory cytokine IL-10, and decreased tissue damage as determined histologically and by measurement of plasma creatinine and alanine aminotransferase activity. Time-expired GYY4137 (50 mg/kg, ip) did not affect the LPS-induced rise in plasma TNF-alpha or lung myeloperoxidase activity. GYY4137 also decreased the LPS-mediated upregulation of liver transcription factors (NF-kappaB and STAT-3). These results suggest an anti-inflammatory effect of GYY4137. The possibility that GYY4137 and other slow-releasing H(2)S donors exert anti-inflammatory activity in other models of inflammation and in humans warrants further study. |
| 2009 | Inhibitory effects of ketamine on lipopolysaccharide-induced microglial activation. | Mediators Inflamm | Microglia activated in response to brain injury release neurotoxic factors including nitric oxide (NO) and proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta). Ketamine, an anesthetic induction agent, is generally reserved for use in patients with severe hypotension or respiratory depression. In this study, we found that ketamine (100 and 250 microM) concentration-dependently inhibited lipopolysaccharide (LPS)-induced NO and IL-1beta release in primary cultured microglia. However, ketamine (100 and 250 microM) did not significantly inhibit the LPS-induced TNF-alpha production in microglia, except at the higher concentration (500 microM). Further study of the molecular mechanisms revealed that ketamine markedly inhibited extracellular signal-regulated kinase (ERK1/2) phosphorylation but not c-Jun N-terminal kinase or p38 mitogen-activated protein kinase stimulated by LPS in microglia. These results suggest that microglial inactivation by ketamine is at least partially due to inhibition of ERK1/2 phosphorylation. |
| 2009 | Central cannabinoid 1 receptor antagonist administration prevents endotoxic hypotension affecting norepinephrine release in the preoptic anterior hypothalamic area. | Shock | It is widely assumed that LPS lowers arterial pressure during sepsis by stimulating release of TNF-alpha and other vasoactive mediators from macrophages. However, recent data from this and other laboratories have shown that LPS hypotension can be prevented by inhibiting afferent impulse flow in the vagus nerve, by blocking neuronal activity in the nucleus of the solitary tract, or by blocking alpha-adrenergic receptors in the preoptic area/anterior hypothalamic area (POA). These findings suggest that the inflammatory signal is conveyed from the periphery to the brain via the vagus nerve, and that endotoxic shock is mediated through a central mechanism that requires activation of POA neurons. In the present study, we tested whether central cannabinoid 1 (CB1) receptors participate in the control of arterial pressure during endotoxemia based on evidence that hypothalamic neurons express CB1 receptors and synthesize the endogenous CB anandamide. We found that intracerebroventricular administration of rimonabant, a CB1 receptor antagonist, inhibited the fall in arterial pressure evoked by LPS significantly in both conscious and anesthetized rats. Rimonabant attenuated both the immediate fall in arterial pressure evoked by LPS and the second, delayed hypotensive phase that leads to tissue ischemia and death. Rimonabant also prevented the associated LPS-induced rise in extracellular fluid norepinephrine concentrations in the POA. Furthermore, rimonabant attenuated the associated increase in plasma TNF-alpha concentrations characteristic of the late phase of endotoxic hypotension. These data indicate that central CB1 receptors may play an important role in the initiation of endotoxic hypotension. |
| 2009 | Effects of propofol on pro-inflammatory cytokines and nuclear factor kappaB during polymicrobial sepsis in rats. | Mol Biol Rep | Nuclear factor kappa B (NF-kappaB) plays a central role in regulating the transcription of several genes associated with sepsis/septic shock. Therefore, the author investigated the effects of propofol on the plasma tumor necrosis factor alpha and interleukin 6 (TNF-alpha and IL-6) levels and NF-kappaB activation during polymicrobial sepsis in rats. Male Sprague-Dawlay rats were subjected to cecal ligation and puncture (CLP, a model of polymicrobial sepsis) or sham operation. The animals were randomly assigned into four equal groups (n = 10): sham CLP group, CLP group, PPF (propofol) I group and PPF II group. Thirty minutes before CLP, propofol (5 and 10 mg kg(-1) h(-1), respectively) was infused continuously through the left femoral vein cannula in PPF I group or PPF II group, CLP group and sham CLP group receiving 0.9% saline only at the rates of 5 ml kg(-1) h(-1). The right femoral artery was cannulated to monitor mean arterial pressure (MAP) and heart rates (HR). CLP produced progressive hypotension and a first increase followed by a decrease in HR. The plasma TNF-alpha and IL-6 levels and the hepatic NF-kappaB activation significantly increased after CLP alone. Compared with CLP group, propofol treatment reversed hypotension, slightly steadied heartbeats, and decreased the plasma TNF-alpha and IL-6 levels, and significantly suppressed NF-kappaB activation. Propofol has inhibited the hepatic NF-kappaB activation and the pro-inflammatory cytokine response during polymicrobial sepsis in rats. |
| 2008 | Why do patients with chagasic cardiomyopathy have worse outcomes than those with non-chagasic cardiomyopathy? | Arq Bras Cardiol | Heart failure is a highly prevalent disease, the prognosis of which depends on different predictive factors.Chagas disease is a predictor of poor prognosis in patients with chronic heart failure (HF). The purpose of this study is to investigate whether this condition also predicts poor outcome in acutely decompensated patients.Four hundred and seventeen patients admitted for decompensated heart failure were studied. Mean age was 51.8 years, and 291 (69.8%) were male. They were divided into two groups: 133 (31.9%) patients with Chagas heart disease (CH) and 284 patients with heart failure of other etiologies. Cytokine and norepinephrine plasma levels were measured in a subgroup of 63 patients (15.1% with Chagas disease).At admission, 24.6% of the patients needed inotropic support, and one-year mortality was 54.7%. Mortality rates were higher in the CH group (69.2% vs. 47.9%, p < 0.001). When data were compared, patients with Chagas disease were younger (47.6 vs. 53.8 years, p < 0.001) and, on average, showed lower systolic blood pressure (96.7 vs. 111.2 mmHg, p < 0,001), ejection fraction (32.7 vs. 36.4%, p < 0.001), and serum Na (134.6 vs. 136.0, p = 0.026), in addition to higher TNF-alpha levels (33.3 vs. 14.8, p = 0.001). The presence of hypotension requiring inotropic support, left ventricular (LV) diastolic diameter, renal function findings, and interleukin-6 and norepinephrine plasma levels did not differ between both groups.Chagas disease patients admitted with decompensated heart failure had worse prognoses than patients with heart failure of other etiologies. This may be owing to a greater degree of cardiac impairment (lower ejection fraction) and hemodynamic instability (lower systolic blood pressure and heart rate), increased activation of the renin-angiotensin system (lower sodium), and increased cytokine levels (TNF-alpha). |
| Inhibitory effects of sesquiterpenes from Saussurea lappa on the overproduction of nitric oxide and TNF-alpha release in LPS-activated macrophages. | J Asian Nat Prod Res | Nitric oxide (NO), derived from L-arginine, is produced by two types (constitutive and inducible) of nitric oxide synthase (NOS: cNOS and iNOS). The NO produced in large amounts by the iNOS is known to be responsible for inflammation, the vasodilation, and hypotension observed in septic shock and cancer metastasis. The inhibitors of the overproduction of NO, thus, may be useful candidates for the treatment of inflammatory diseases. We have found that the petroleum ether extract of Saussurea lappa Decne, which is a wild species wildly distributed in India, can strongly inhibit the overproduction of NO in mouse macrophage RAW 264.7 cells. Through bioassay-guided fractionation, 13 sesquiterpenes were isolated from the active petroleum ether extract. Furthermore, another five sesquiterpenes were synthesized by chemical methods. In the present study, their effects on LPS-induced NO production and TNF-alpha release are reported. Compounds 1, 3, 9, 17, and 18 showed significant inhibitory activities on the production of NO and release of TNF-alpha with IC(50) values lower than 1 micromol/l. SAR studies suggest that the exocyclic double bond (Delta(11(13))) is necessary for the inhibitory activities of sesquiterpenes on the NO production. |
| 2009 | High versus standard-volume haemofiltration in hyperdynamic porcine peritonitis: effects beyond haemodynamics? | Intensive Care Med | The role of haemofiltration as an adjunctive treatment of sepsis remains a contentious issue. To address the role of dose and to explore the biological effects of haemofiltration we compared the effects of standard and high-volume haemofiltration (HVHF) in a peritonitis-induced model of porcine septic shock.Randomized, controlled experimental study.Twenty-one anesthetized and mechanically ventilated pigs.After 12 h of hyperdynamic peritonitis, animals were randomized to receive either supportive treatment (Control, n = 7) or standard haemofiltration (HF 35 ml/kg per h, n = 7) or HVHF (100 ml/kg per hour, n = 7).Systemic and hepatosplanchnic haemodynamics, oxygen exchange, energy metabolism (lactate/pyruvate, ketone body ratios), ileal and renal cortex microcirculation and systemic inflammation (TNF-alpha, IL-6), nitrosative/oxidative stress (TBARS, nitrates, GSH/GSSG) and endothelial/coagulation dysfunction (von Willebrand factor, asymmetric dimethylarginine, platelet count) were assessed before, 12, 18, and 22 h of peritonitis. Although fewer haemofiltration-treated animals required noradrenaline support (86, 43 and 29% animals in the control, HF and HVHF groups, respectively), neither of haemofiltration doses reversed hyperdynamic circulation, lung dysfunction and ameliorated alterations in gut and kidney microvascular perfusion. Both HF and HVHF failed to attenuate sepsis-induced alterations in surrogate markers of cellular energetics, nitrosative/oxidative stress, endothelial injury or systemic inflammation.In this porcine model of septic shock early HVHF proved superior in preventing the development of septic hypotension. However, neither of haemofiltration doses was capable of reversing the progressive disturbances in microvascular, metabolic, endothelial and lung function, at least within the timeframe of the study and severity of the model. |
| 2008 | Ketamine-based total intravenous anesthesia versus isoflurane anesthesia in a swine model of hemorrhagic shock. | J Trauma | Inhalational anesthetics can cause profound hemodynamic effects including decreases in systemic vascular resistance and cardiac inotropy. Although widely used in uncontrolled hemorrhagic shock (UHS), their consequences compared with other anesthetic regimens are not well-studied. Ketamine-based total intravenous anesthesia (TIVA) may produce less profound cardiovascular depression, and has been used during elective surgery but rarely during traumatic shock. The purpose of this study was to compare the effects of isoflurane (ISO) and TIVA regimens in a swine grade V liver injury model. We hypothesized that TIVA would result in less hypotension and dysfunctional inflammation than ISO.Twenty swine were randomized blindly to receive either 1% to 3% ISO, or intravenous ketamine, midazolam, and buprenorphine for maintenance anesthesia. Six animals acted as controls. After sedation and intubation, randomized anesthesia was initiated and monitored by an independent animal technician. Invasive lines were placed followed by celiotomy and splenectomy. Baseline mean arterial pressure (MAP) was documented and a grade V liver injury created. After 30 minutes of UHS, animals were resuscitated with 8 mL of Ringer's lactate per milliliter blood loss at 165 mL/min. MAP and tissue oxygen saturation (StO2) were continuously recorded. The animals were sacrificed 120 minutes after injury and lung tissue was harvested. Serum cytokines (interleukin-6 [IL-6], IL-8, and tumor necrosis factor-alpha [TNF-alpha]) were quantified with enzyme-linked immunosorbent assay. Lung cytokine mRNA levels were quantified with real time reverse transcriptase polymerase chain reaction.Animal weight, liver injury pattern, and blood loss were similar (p > 0.1). The ISO group had a lower MAP at baseline (p = 0.02), at injury (p = 0.004), and study completion (p = 0.001). After resuscitation, MAP decreased in the ISO group but remained stable in the TIVA group. StO2 was significantly higher in the TIVA group immediately after injury (p = 0.004), but similar between groups throughout the remainder of the study. Animals who received TIVA trended toward higher levels of lactate and lower pH throughout the study, reaching significance at 30 minutes postinjury (p = 0.037 and 0.043). Inflammatory cytokine (IL-6, IL-8, and TNF-alpha) production did not differ between groups, however TNF-alpha mRNA production was significantly lower in the TIVA group (p = 0.04).Although a TIVA regimen produced less pronounced hypotension in a swine model of UHS than did ISO, end-organ perfusion with TIVA appeared to be equivalent or inferior to ISO. In circumstances of limited resources, such as those experienced by forward Army surgical teams, a ketamine-based TIVA regimen may be an option for use in UHS. |
| 2009 | Soluble TNFR II/IgG1 Fc fusion protein treatment in the LPS-mediated septic shock of rats. | Biomed Pharmacother | Tumor necrosis factor-alpha (TNF-alpha) is thought to play a major role in systemic inflammation associated with sepsis. A potent TNF antagonist, a recombinant fusion protein that consists of the soluble TNF receptor (p75) linked to the Fc portion of human IgG1 (sTNFR II/IgG1 Fc fusion protein, sTNFR:Fc), has been shown to provide rapid and sustained improvement in local inflammation diseases by binding TNF-alpha and preventing its proinflammatory activities. To explore the potential therapeutic efficacy for septic shock of sTNFR:Fc, we investigate the effect of this molecule on the survival rate, blood pressure, serum TNF-alpha bioactivity as well as the expression of TNF-alpha at mRNA level in the liver in a LPS-induced rat septic shock model. Blood pressure of the rats was monitored by multi-channel creature signal analysis system. Serum TNF-alpha level and bioactivity was assessed using an enzyme-linked immunoassay and a L929 cytotoxicity assay, respectively. The expression of TNF-alpha mRNA in liver was examined by semi-quantitative RT-PCR. sTNFR:Fc administered to rats 24h before LPS challenge ablated the rise in serum TNF-alpha bioactivity that occurs in response to LPS and protected against hypotension and death. These results indicate that TNF-alpha is a mediator of fatal septic shock, and suggest that sTNFR:Fc offer a potential therapy of systemic infection. |
| 2009 | Coupled plasma filtration adsorption in experimental peritonitis-induced septic shock. | Shock | The coupled plasma filtration adsorption (CPFA) was developed as an adsorptive hemopurification method aimed at nonselective removal of circulating soluble mediators potentially involved in the pathogenesis of sepsis. We hypothesized that this nonselective hemopurification could protect from detrimental consequences of long-term, volume-resuscitated porcine septic shock. In 16 anesthetized, mechanically ventilated, and instrumented pigs, the hyperdynamic septic shock secondary to peritonitis was induced by intraperitoneally inoculating feces and maintained for 22 h with fluid resuscitation and norepinephrine infusion as needed to maintain MAP above 65 mmHg. After 12 h of peritonitis, animals were randomized to receive either supportive treatment (control, n = 8) or CPFA treatment (CPFA, n = 8). Systemic, hepatosplanchnic, and renal hemodynamics; oxygen exchange; energy metabolism (lactate/pyruvate and ketone body ratios); ileal mucosal and renal cortex microcirculation; systemic inflammation (TNF-alpha, IL-6); nitrosative/oxidative stress (thiobarbituric acid reactive species, nitrates + nitrites); and endothelial/coagulation dysfunction (asymmetric dimethylarginine, von Willebrand factor, thrombin-antithrombin complexes, platelet count) were assessed before and 12, 18, and 22 h of peritonitis. Coupled plasma filtration adsorption neither delayed the development of hypotension nor reduced the dose of norepinephrine. The treatment failed to attenuate sepsis-induced alterations in microcirculation, surrogate markers of cellular energetics, endothelial injury, and systemic inflammation. Similarly, CPFA did not protect from lung and liver dysfunction and even aggravated sepsis-induced disturbances in coagulation and oxidative/nitrosative stress. In this porcine model of septic shock, the early treatment with CPFA was not capable of reversing the sepsis-induced disturbances in various biological pathways and organ systems. Both the efficacy and safety of this method require further rigorous experimental validation in clinically relevant models. |
| 2008 | Splenic nerve is required for cholinergic antiinflammatory pathway control of TNF in endotoxemia. | Proc Natl Acad Sci U S A | The autonomic nervous system maintains homeostasis through its sympathetic and parasympathetic divisions. During infection, cells of the immune system release cytokines and other mediators that cause fever, hypotension, and tissue injury. Although the effect of cytokines on the nervous system has been known for decades, only recently has it become evident that the autonomic nervous system, in turn, regulates cytokine production through neural pathways. We have previously shown that efferent vagus nerve signals regulate cytokine production through the nicotinic acetylcholine receptor subunit alpha7, a mechanism termed "the cholinergic antiinflammatory pathway." Here, we show that vagus nerve stimulation during endotoxemia specifically attenuates TNF production by spleen macrophages in the red pulp and the marginal zone. Administration of nicotine, a pharmacological agonist of alpha7, attenuated TNF immunoreactivity in these specific macrophage subpopulations. Synaptophysin-positive nerve endings were observed in close apposition to red pulp macrophages, but they do not express choline acetyltransferase or vesicular acetylcholine transporter. Surgical ablation of the splenic nerve and catecholamine depletion by reserpine indicate that these nerves are catecholaminergic and are required for functional inhibition of TNF production by vagus nerve stimulation. Thus, the cholinergic antiinflammatory pathway regulates TNF production in discrete macrophage populations via two serially connected neurons: one preganglionic, originating in the dorsal motor nucleus of the vagus nerve, and the second postganglionic, originating in the celiac-superior mesenteric plexus, and projecting in the splenic nerve. |
| 2008 | Latanoprost-induced changes in rat intraocular pressure: direct or indirect? | J Ocul Pharmacol Ther | The topical application of prostaglandin F(2 ) (FP)-receptor agonists has been shown to significantly lower intraocular pressure (IOP) in humans and is now considered the first-line treatment for ocular hypertension. Despite the prominent role FP-receptor agonists play in the treatment of glaucoma, our understanding of how these agents lower IOP remains incomplete. The present study was designed to evaluate the role of matrix metalloproteinase (MMP) activation and the cytokine, tumor necrosis factor alpha (TNF-alpha), in latanoprost-induced changes in IOP.Changes in IOP following an acute topical administration of latanoprost (60 ng) in normotensive Brown Norway rats were evaluated by means of a commercially available rebound tonometer. To examine the role of MMPs and TNF-alpha in this response, the rats were pretreated with a broad-spectrum MMP inhibitor, GM-6001 (100 microg), or the TNF-alpha inhibitor, thalidomide (25 microg).The topical administration of latanoprost (60 ng) alone produced a biphasic change in ipsilateral IOP: an initial hypertension (4.21 +/- 0.52), followed by a prolonged hypotension (-4.79 +/- 0.65). In rats, pretreatment with GM-6001 blocked the latanoprost-induced reduction in IOP but did not prevent the initial rise in IOP. Pretreatment with thalidomide also blocked the ocular hypotension induced by latanoprost; however, thalidomide pretreatment enhanced the duration of the initial hypertension.These results provide evidence that the secretion and activation of MMPs and the release of TNF-alpha play a central role in the ocular hypotension induced by FP-agonists. The administration of FP-agonists appears to lower IOP directly by inducing the activation of MMPs within the ciliary body, leading to improved uveoscleral outflow and indirectly through the release of TNF within the ciliary body. Secreted TNF-alpha may then activate TNF-receptors in the uvea and trabecular meshwork, increasing both uveoscleral and conventional outflow. |
| 2008 | The level of hypotension during hemorrhagic shock is a major determinant of the post-resuscitation systemic inflammatory response: an experimental study. | BMC Physiol | To evaluate whether the level of hypotension during hemorrhagic shock may influence the oxidative and inflammatory responses developed during post-ischemic resuscitation.Fifteen rabbits were equally allocated into three groups: sham-operated (group sham); bled within 30 minutes to mean arterial pressure (MAP) of 40 mmHg (group shock-40); bled within 30 minutes to MAP of 30 mmHg (group shock-30). Shock was maintained for 60 min. Resuscitation was performed by reinfusing shed blood with two volumes of Ringer's lactate and blood was sampled for estimation of serum levels aminotransferases, creatinine, TNF-alpha, IL-1beta, IL-6, malondialdehyde (MDA) and total antioxidant status (TAS) and for the determination of oxidative burst of polymorhonuclears (PMNs) and mononuclear cells (MCs).Serum AST of group shock-30 was higher than that of group shock-40 at 60 and 120 minutes after start of resuscitation; serum creatinine of group shock-30 was higher than group shock-40 at 120 minutes. Measured cytokines, MDA and cellular oxidative burst of groups, shock-40 and shock-30 were higher than group sham within the first 60 minutes after start of resuscitation. Serum concentrations of IL-1beta, IL-6 and TNF-alpha of group shock-30 were higher than group shock-40 at 120 minutes (p < 0.05). No differences were found between two groups regarding serum MDA and TAS and oxidative burst on PMNs and MCs but both groups were different to group sham.The level of hypotension is a major determinant of the severity of hepatic and renal dysfunction and of the inflammatory response arising during post-ischemic hemorrhagic shock resuscitation. These findings deserve further evaluation in the clinical setting. |
| 2008 | Selective inhibition of iNOS attenuates trauma-hemorrhage/resuscitation-induced hepatic injury. | J Appl Physiol (1985) | Although trauma-hemorrhage produces tissue hypoxia, systemic inflammatory response and organ dysfunction, the mechanisms responsible for these alterations are not clear. Using a potent selective inducible nitric oxide (NO) synthase inhibitor, N-[3-(aminomethyl) benzyl]acetamidine (1400W), and a nonselective NO synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), we investigated whether inducible NO synthase plays any role in producing hepatic injury, inflammation, and changes of protein expression following trauma-hemorrhage. To investigate this, male Sprague-Dawley rats were subjected to midline laparotomy and hemorrhagic shock (mean blood pressure 35-40 mmHg for approximately 90 min) followed by fluid resuscitation. Animals were treated with either vehicle (DMSO) or 1400W (10 mg/kg body wt ip), or L-NAME (30 mg/kg iv), 30 min before resuscitation and killed 2 h after resuscitation. Trauma-hemorrhage/resuscitation induced a marked hypotension and increase in markers of hepatic injury (i.e., plasma alpha-glutathione S-transferase, tissue myeloperoxidase activity, and nitrotyrosine formation). Hepatic expression of iNOS, hypoxia-inducible factor-1alpha, ICAM-1, IL-6, TNF-alpha, and neutrophil chemoattractant (cytokine-induced neutrophil chemoattractant-1 and macrophage inflammatory protein-2) protein levels were also markedly increased following trauma-hemorrhage/resuscitation. Administration of the iNOS inhibitor 1400W significantly attenuated hypotension and expression of these mediators of hepatic injury induced by trauma-hemorrhage/resuscitation. However, administration of L-NAME could not attenuate hepatic dysfunction and tissue injury mediated by trauma-hemorrhage, although it improved mean blood pressure as did 1400W. These results indicate that increased expression of iNOS following trauma-hemorrhage plays an important role in the induction of hepatic damage under such conditions. |
| 2008 | Betagamma-CAT, a non-lens betagamma-crystallin and trefoil factor complex from amphibian skin secretions, caused endothelium-dependent myocardial depression in isolated rabbit hearts. | Toxicon | Previous in vivo study demonstrated that betagamma-CAT, a newly identified non-lens betagamma-crystallin and trefoil factor complex from frog Bombina maxima skin secretions, possessed potent lethal toxicity on mammals resulted from hypotension and cardiorespiratory arrest. However, the mechanism of cardiac dysfunction induced by the protein is unknown. Here, we report that betagamma-CAT, with dosages of 0.8-3.0 nM, elicited an acute negative inotropic effect in isolated rabbit heart Langendorff preparations, which mimicked acute heart failure. In addition, the effect of betagamma-CAT on the hearts was mediated by endothelium-dependent coronary vasoconstriction (P<0.01, compared between endothelium-intact and removal hearts). After betagamma-CAT (3.0 nM) treatment, the positive signal of tumor necrosis factor-alpha (TNF-alpha) was detected mainly around the endothelial cell layer as detected by in situ indirect immunofluorescence, indicating that the release of TNF-alpha occurred. At the same time, a rapid TNF-alpha release was detected in primary cultured rabbit endocardial endothelial cells (REECs) treated with betagamma-CAT. After addition of betagamma-CAT (3.0 nM) for 10 min and 30 min, the TNF-alpha levels were increased to 57.33+/-3.22 pg/ml and 60.00+/-5.35 pg/ml (P<0.05, compared with the control values of 21.67+/-3.45 pg/ml and 33.70+/-6.24 pg/ml, respectively). At high concentrations, betagamma-CAT interfered with the cell viability of REECs (CC(50) about 25 nM). Taken together, betagamma-CAT was able to induce acute myocardial depression and the toxic effect might be partially explained by the release of TNF-alpha. The finding provides new information to understand the patho-physiological roles of non-lens betagamma-crystallins and trefoil factors. |
| 2008 | Multiplex cytokine profile from dengue patients: MIP-1beta and IFN-gamma as predictive factors for severity. | BMC Infect Dis | Dengue virus pathogenesis is not yet fully understood and the identification of patients at high risk for developing severe disease forms is still a great challenge in dengue patient care. During the present study, we evaluated prospectively the potential of cytokines present in plasma from patients with dengue in stratifying disease severity.Seventeen-cytokine multiplex fluorescent microbead immunoassay was used for the simultaneous detection in 59 dengue patients. GLM models using bimodal or Gaussian family were determined in order to associate cytokines with clinical manifestations and laboratory diagnosis.IL-1beta, IFN-gamma, IL-4, IL-6, IL-13, IL-7 and GM-CSF were significantly increased in patients with severe clinical manifestations (severe dengue) when compared to mild disease forms (mild dengue). In contrast, increased MIP-1beta levels were observed in patients with mild dengue. MIP-1beta was also associated with CD56+NK cell circulating rates. IL-1beta, IL-8, TNF-alpha and MCP-1 were associated with marked thrombocytopenia. Increased MCP-1 and GM-CSF levels correlated with hypotension. Moreover, MIP-1beta and IFN-gamma were independently associated with both dengue severity and disease outcome.Our data demonstrated that the use of a multiple cytokine assay platform was suitable for identifying distinct cytokine profiles associated with the dengue clinical manifestations and severity. MIP-beta is indicated for the first time as a good prognostic marker in contrast to IFN-gamma that was associated with disease severity. |
| 2008 | Lipopolysaccharide-induced carotid body inflammation in cats: functional manifestations, histopathology and involvement of tumour necrosis factor-alpha. | Exp Physiol | In the absence of information on functional manifestations of carotid body (CB) inflammation, we studied an experimental model in which lipopolysaccharide (LPS) administration to pentobarbitone-anaesthetized cats was performed by topical application upon the CB surface or by intravenous infusion (endotoxaemia). The latter caused: (i) disorganization of CB glomoids, increased connective tissue, and rapid recruitment of polymorphonuclear cells into the vascular bed and parenchyma within 4 h; (ii) increased respiratory frequency and diminished ventilatory chemoreflex responses to brief hypoxia (breathing 100% N(2) for 10 s) and diminished ventilatory chemosensory drive (assessed by 100% O(2) tests) during normoxia and hypoxia; (iii) tachycardia, increased haematocrit and systemic hypotension in response to LPS i.v.; and (iv) increased basal frequency of carotid chemosensory discharges during normoxia, but no change in maximal chemoreceptor responses to brief hypoxic exposures. Lipopolysaccharide-induced tachypnoea was prevented by prior bilateral carotid neurotomy. Apoptosis was not observed in CBs from cats subjected to endotoxaemia. Searching for pro-inflammatory mediators, tumour necrosis factor-alpha (TNF-alpha) was localized by immunohistochemistry in glomus and endothelial cells; reverse transcriptase-polymerase chain reaction revealed that the CB expresses the mRNAs for both type-1 (TNF-R1) and type-2 TNF-alpha receptors (TNF-R2); Western blot confirmed a band of the size expected for TNF-R1; and histochemistry showed the presence of TNF-R1 in glomus cells and of TNF-R2 in endothelial cells. Experiments in vitro showed that the frequency of carotid nerve discharges recorded from CBs perfused and superfused under normoxic conditions was not significantly modified by TNF-alpha, but that the enhanced frequency of chemosensory discharges recorded along responses to hypoxic stimulation was transiently diminished in a dose-dependent manner by TNF-alpha injections. The results suggest that the CB may operate as a sensor for immune signals, that the CB exhibits histological features of acute inflammation induced by LPS, that TNF-alpha may participate in LPS-induced changes in chemosensory activity and that some pathophysiological reactions to high levels of LPS in the bloodstream may originate from changes in CB function. |
| 2008 | Trehalose: a biophysics approach to modulate the inflammatory response during endotoxic shock. | Eur J Pharmacol | We evaluated the effects of trehalose against endotoxic shock, a condition in which the loss of bio-membrane integrity plays a pivotal role. In addition we performed a biophysics experiment by quasi elastic neutron scattering (QENS) study, to investigate whether the membrane stability effect of trehalose might be correlated with its high capability to switch-off the water diffusive dynamics and, hence, the kinetic mechanisms of interaction. Endotoxic shock was induced in male rats by a single injection of Salmonella enteritidis lipopolysaccharide (LPS; 20 mg/kg/i.p.). Thirty minutes before and 2 h after LPS injection, the animals were randomized to receive vehicle (1 ml/kg/i.p. 0.9%NaCl), sucrose (1 g/kg/i.p.) or trehalose (1 g/kg/i.p.). Mean arterial blood pressure, nuclear factor-kappaB (NF-kappaB) binding activity, Ikappa-Balpha and toll-like receptor-4 (TLR-4) activation were evaluated in both liver and lung. Plasmatic tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-6 (IL-6) and malondialdehyde (MDA) were also investigated. We studied liver injury by means of blood alanine aminotransferase activity (ALT); inducible nitric oxide synthase (iNOS) expression, myeloperoxidase (MPO) activity and tissue edema evaluation. Lung injury was investigated by means of tissue monocyte chemoattractant protein-1 (MCP-1) levels, MPO activity, iNOS expression and edema formation. Trehalose reduced hypotension, NF-kappaB binding activity, IkappaBalpha protein loss and TLR-4 activation. In addition trehalose reduced TNF-alpha, IL-1, IL-6 and MDA levels. Trehalose also blunted liver and lung injury. QENS measurements showed also that trehalose possesses a high "switching off" capability. Sucrose did not modify endotoxic shock-induced sequelae. Trehalose blocked the inflammatory cascade triggered by endotoxin shock, stabilizing the bio-membranes and switching off the water diffusive dynamics. |
| 2008 | Anti-TNF-alpha therapy in patients with chronic non-infectious uveitis: the experience of Jules Gonin Eye Hospital. | Klin Monbl Augenheilkd | The purpose of this study is to describe the experience of Jules Gonin Eye Hospital on the long-term outcome of anti-TNF-alpha therapy in chronic non-infectious uveitis.We identified and followed those patients with chronic non-infectious uveitis who received systemic anti-TNF-alpha therapy. Anti-TNF-alpha therapy was administered when no response had been obtained with classical immunosuppressive therapies or in the presence of severe rheumatoid disease.Fifteen patients (28 eyes), 7 male and 8 female (mean age, 43 years; range: 7 to 70 years) were identified. Diagnoses included HLA-B27-associated anterior uveitis (n = 4), sarcoidosis (n = 2), juvenile idiopathic arthritis (n = 2), idiopathic retinal vasculitis with uveitis (n = 2), pars planitis (n = 2), Adamantiades-Behçet disease (n = 1), birdshot retinochoroidopathy (n = 1), and Crohn's disease (n = 1). Mean duration of ocular disease was 8 years (range: 1 to 29 years). Treatment with infliximab (n = 11), etanercept (n = 2), or adalimumab (n = 2) was initiated. One patient with etanercept was switched to infliximab due to lack of clinical response. Clinical and angiographic regression of uveitis was observed within the first two months of therapy in all patients, and was maintained throughout the entire follow-up period (mean 18 months; range: 3 - 72 months). Recurrence was observed in 3 patients, and resolved after adjustment of therapy. Adverse events were recorded in only one patient (arterial hypotension).In this series of patients with chronic non-infectious uveitis, anti-TNF-alpha therapy was effective and safe. Further clinical studies are needed to determine an adequate duration of therapy. |
| 2008 | The protective effect of the cholinergic anti-inflammatory pathway against septic shock in rats. | Shock | To investigate the effects of the cholinergic anti-inflammatory pathway on hemodynamics, blood biochemistry, the plasma TNF-alpha level, and the nuclear factor-kappaB (NF-kappaB) activation during septic shock, male Sprague-Dawley rats were subjected to cecal ligation and puncture (CLP, a model of polymicrobial sepsis) or sham operation. Forty-eight rats were randomly assigned into six equal groups: sham CLP group; CLP group; VGX group was subjected to bilateral cervical vagotomy after CLP; STM group was subjected to bilateral cervical vagotomy after CLP plus the left vagus nerve trunk electrical stimulation; THA group was administered tetrahydroaminoacridine after CLP and bilateral cervical vagotomy; and alpha-BGT group was administered alpha-bungarotoxin before electrical stimulation of the vagus nerve. The right carotid artery was cannulated to monitor MAP. The plasma TNF-alpha level was measured using enzyme-linked immunosorbent assays. The hepatic NF-kappaB activation was determined by Western blotting. Cecal ligation and puncture produced progressive hypotension. Serum aspartate transaminase and alanine transaminase levels significantly increased after CLP challenge. The plasma TNF-alpha level and the hepatic NF-kappaB activation significantly increased after CLP alone or with bilateral cervical vagotomy compared with sham-operated group. Application of constant voltage pulses to the caudal vagus trunk significantly prevented the development of CLP-induced hypotension, alleviated the hepatic damage, and reduced the plasma TNF-alpha production, but electrical stimulation had no effect on the hepatic NF-kappaB activation. Tetrahydroaminoacridine administration after bilateral cervical vagotomy reversed hypotension and attenuated the plasma TNF-alpha response; in addition, it had no effect on the hepatic NF-kappaB activation. alpha-Bungarotoxin pretreatment significantly reversed the inhibitory effect of vagal electrical stimulation, but it had no effect on the hepatic NF-kappaB activation. Our results showed that the cholinergic anti-inflammatory pathway might produce a potential protective effect on polymicrobial sepsis in rats. |
| 2008 | The preoptic anterior hypothalamic area mediates initiation of the hypotensive response induced by LPS in male rats. | Shock | The mechanism responsible for the initiation of endotoxic hypotension is not fully understood, although it is often attributed to a direct effect of LPS and other vasoactive mediators on the vasculature. Alternatively, recent evidence raises the possibility that endotoxic hypotension may be initiated through a central mechanism. Previous studies have shown that LPS initiates fever, sickness behavior, and other aspects of the inflammatory response through a neural pathway that sends peripheral inflammatory signals to the preoptic anterior hypothalamic area (POA). It is also well known that the POA plays a role in the regulation of cardiovascular function, but its involvement in LPS-induced hypotension has not been examined previously. Therefore, the aim of the present paper was to investigate whether the initial abrupt fall in arterial pressure evoked by LPS in septic shock is mediated by the POA. LPS (1 mg/kg, i.v.) administration to halothane-anesthetized or conscious rats lowered arterial blood pressure by 24.8+/-2.9 and 25.1+/-5.8 mmHg, respectively. Bilateral lidocaine (2%; 1 microL) injection into the POA, but not the lateral hypothalamus, prevented the hypotension evoked by LPS entirely in both anesthetized and conscious animals. Remarkably, this blockade significantly inhibited the second, delayed fall in arterial pressure induced by LPS, and simultaneously decreased TNF-alpha plasma levels. Together, these data indicate that the initial phase of endotoxic hypotension is mediated by the POA and suggest that the initiation of the hypotensive response induced by LPS can be essential for the development of the late fall in blood pressure. |
| 2008 | AP214, an analogue of alpha-melanocyte-stimulating hormone, ameliorates sepsis-induced acute kidney injury and mortality. | Kidney Int | Sepsis remains a serious problem in critically ill patients with the mortality increasing to over half when there is attendant acute kidney injury. alpha-Melanocyte-stimulating hormone is a potent anti-inflammatory cytokine that inhibits many forms of inflammation including that with acute kidney injury. We tested whether a new alpha-melanocyte-stimulating hormone analogue (AP214), which has increased binding affinity to melanocortin receptors, improves sepsis-induced kidney injury and mortality using a cecal ligation and puncture mouse model. In the lethal cecal ligation-puncture model of sepsis, severe hypotension and bradycardia resulted and AP214 attenuated acute kidney injury of the lethal model with a bell-shaped dose-response curve. An optimum AP214 dose reduced acute kidney injury even when it was administered 6 h after surgery and it significantly improved blood pressure and heart rate. AP214 reduced serum TNF-alpha and IL-10 levels with a bell-shaped dose-response curve. Additionally; NF-kappaB activation in the kidney and spleen, and splenocyte apoptosis were decreased by the treatment. AP214 significantly improved survival in both lethal and sublethal models. We have shown that AP214 improves hemodynamic failure, acute kidney injury, mortality and splenocyte apoptosis attenuating pro- and anti-inflammatory actions due to sepsis. |
| 2008 | Role of neutrophil elastase in development of pulmonary vascular injury and septic shock in rats. | Shock | Prostacyclin prevents pulmonary vascular injury and shock by inhibiting increases in lung tissue levels of TNF in rats administered endotoxin. We previously reported that NO derived from eNOS increases endothelial production of prostacyclin. Because neutrophil elastase has been shown to decrease endothelial production of prostacyclin by inhibiting NOS activity, we examined whether neutrophil elastase inhibitors reduce pulmonary vascular injury and hypotension by inhibiting the decrease in pulmonary endothelial production of prostacyclin in rats administered endotoxin. Animals were pretreated with sivelestat or L-658,758, neutrophil elastase inhibitors, before endotoxin administration. Lung tissue levels of 6-keto-prostaglandin F1alpha were markedly increased after endotoxin administration, followed by a rapid decrease to baseline levels. Sivelestat and L-658,758 inhibited these decreases as well as inhibiting increases in lung tissue levels of TNF and lung wet-to-dry weight ratios in animals administered endotoxin. These inhibitors also reduced hypotension and inhibited increases in lung tissue levels of mRNA of the inducible form of NOS in animals administered endotoxin. The effects of neutrophil elastase inhibitors were completely reversed by pretreatment with nitro-L-arginine methyl ester, an inhibitor of NOS, or indomethacin, a nonspecific cyclooxygenase inhibitor. These observations suggested that neutrophil elastase might decrease the pulmonary endothelial production of prostacyclin by inhibiting endothelial NO production, thereby contributing to the development of pulmonary vascular injury and shock through increases in lung tissue levels of TNF in rats administered endotoxin. |
| 2008 | Ultrastructural changes, nuclear factor-kappaB activation, and tumor necrosis factor-alpha expression in brain after acute normovolemic hemodilution and controlled hypotension in rats. | Croat Med J | To examine brain damage following different degrees of acute normovolemic hemodilution combined with controlled hypotension (ANH-CH) by neuronal morphological analysis and investigate the expression of nuclear factor-kappa B (NF-kappaB) activity and tumor necrosis factor-alpha (TNF-alpha) in the rat.Forty rats were randomly assigned to receive a sham operation or ANH-CH (with hematocrit 30%, 25%, 20%, and 15%). ANH was performed after baseline physiological parameters had been monitored for 20 minutes. CH was induced 30 minutes later using sodium nitroprusside and mean arterial pressure was maintained at 50-60 mm Hg for 1 hour. Rats were euthanatized 3 and a half hours after operation. TNF-alpha levels and NF-kappaB activities in cerebral temporal cortex were measured. Ultrastructural alterations in the CA1 region of the rat hippocampi were observed. Changes in mitochondria were evaluated semiquantitatively.Marked ultrastructural alterations, such as mitochondrial denaturalization and nucleus distortion, were observed in the CA1 region of the hippocampus in the ANH-CH hematocrit 20% group and ANH-CH hematocrit 15% group. TNF-alpha expression and NF-kappaB activity in the cerebral temporal cortex significantly increased in all ANH-CH groups and peaked in the ANH-CH hematocrit 25% group.Severe ANH-CH with hematocrit < or =20% may induce cerebral damage and should be avoided. NF-kappaB activation and TNF-alpha expression may play a functional role under the ischemic condition. A better understanding of the role of NF-kappaB and TNF-alpha in the brain may lead to a novel approach for preventing and treating various neurological disorders. |
| 2008 | Low-dose propofol ameliorates haemorrhagic shock-induced organ damage in conscious rats. | Clin Exp Pharmacol Physiol | 1. Propofol is an anti-inflammatory agent commonly used for general anaesthesia and sedation in intensive care unit patients. Haemorrhagic shock (HS) followed by resuscitation can induce the production of several inflammatory mediators, such as tumour necrosis factor (TNF)-a and interleukin (IL)-10, leading to multiple organ dysfunction and death. 2. In the present study, we investigated the effects of treatment with high-dose (10 mg/kg per h) and low-dose (1 mg/kg per h) propofol after HS on the physiopathology and cytokine levels in conscious rats. 3. The experiments were designed to induce HS by withdrawing 40% of total blood volume from a femoral artery catheter (6 mL/100 g bodyweight) over 30 min. Mean arterial pressure (MAP) and heart rate (HR) were monitored continuously for 48 h after the start of blood withdrawal. Levels of biochemical parameters, including glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), blood urea nitrogen (BUN), creatinine, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH), were measured 30 min before and 0, 1, 3, 6, 9, 12, 18, 24 and 48 h after the end of the 30 min blood withdrawal period. Serum cytokine levels, including TNF-a and IL-10, were measured at 1, 6, 12, 24 and 48 h after HS. The kidneys, liver, lungs and small intestine were removed for pathological assessment 48 h after HS. 4. In the present study, HS significantly increased blood GOT, GPT, BUN, LDH, CPK, TNF-a and IL-10 levels in conscious rats. Post-treatment with high-dose propofol accentuated systemic hypotension, increased serum TNF-a and IL-10 levels and increased the severity of organ damage after HS. In contrast, post-treatment with low-dose propofol did not affect MAP, but did suppress increased serum levels of the inflammatory cytokines and improved the survival rate after HS, thus protecting rats against HS-induced organ damage. 5. In conclusion, post-treatment with low-dose propofol ameliorated HS-induced markers of organ injury, suppressed the release of TNF-a and IL-10 and protected against HS-induced liver, kidney, lung and small intestine damage in conscious rats. These findings suggest the need to investigate whether low-dose propofol may be beneficial for patients with HS-induced organ damage. |
| 2007 | An in vitro model for dengue virus infection that exhibits human monocyte infection, multiple cytokine production and dexamethasone immunomodulation. | Mem Inst Oswaldo Cruz | An important cytokine role in dengue fever pathogenesis has been described. These molecules can be associated with haemorrhagic manifestations, coagulation disorders, hypotension and shock, all symptoms implicated in vascular permeability and disease worsening conditions. Several immunological diseases have been treated by cytokine modulation and dexamethasone is utilized clinically to treat pathologies with inflammatory and autoimmune etiologies. We established an in vitro model with human monocytes infected by dengue virus-2 for evaluating immunomodulatory and antiviral activities of potential pharmaceutical products. Flow cytometry analysis demonstrated significant dengue antigen detection in target cells two days after infection. TNF-alpha, IFN-alpha, IL-6 and IL-10 are produced by in vitro infected monocytes and are significantly detected in cell culture supernatants by multiplex microbead immunoassay. Dexamethasone action was tested for the first time for its modulation in dengue infection, presenting optimistic results in both decreasing cell infection rates and inhibiting TNF-alpha, IFN-alpha and IL-10 production. This model is proposed for novel drug trials yet to be applied for dengue fever. |
| 2008 | Perfluorocarbon administration during cardiopulmonary bypass in rats: an inflammatory link to adverse outcome? | Anesth Analg | Perfluorocarbon (PFC) emulsions are artificial oxygen carriers that have been shown to attenuate the effects of air embolism. Cerebral air embolism, known to occur during cardiopulmonary bypass (CPB), may contribute to adverse cerebral outcomes after cardiac surgery. We designed this study to evaluate the effect of a 60% PFC emulsion (perfluoro-tert-butylcyclohexane; PTBCH) on the inflammatory response and neurocognitive outcome of rats after CPB.Twenty-eight Sprague Dawley rats subjected to 60 min of CPB were randomly divided into two groups: PTBCH CPB animals receiving 3 mL/kg of PTBCH into the venous reservoir and control CPB animals receiving 3 mL/kg of 0.9% saline. At several time points, the cytokines interleukin (IL)-1beta, IL-6, IL-10, and tumor necrosis factor (TNF)-alpha were measured. Neurocognitive testing was planned postoperatively using the Morris water maze. Histologic samples were obtained in a separate series of experiments.Physiologic variables were comparable between groups, but the PTBCH CPB animals required more phenylephrine compared with the controls. Cytokine levels in the PTBCH CPB group were significantly higher than in the control group at 2 and 4 h after CPB (P < 0.05). Neurocognitive outcome could not be evaluated as none of the animals in the PTBCH CPB group survived. Myocardial histological analysis revealed increased areas of contraction band necrosis in the PTBCH CPB animals (P = 0.034).Administration of PTBCH during CPB was associated with an excessive release of cytokines. This enhanced inflammatory response with subsequent hypotension may have contributed to mortality in rats receiving PTBCH. The observed patterns of myocardial injury indicate global hypoperfusion and catecholamine excess. |
| 2008 | Is There NO Treatment For Severe Sepsis? | Libyan J Med | Sepsis is a systemic inflammatory response syndrome in the presence of suspected or proven infection, and it may progress to or encompass organ failure (severe sepsis) and hypotension (septic shock). Clinicians possess an arsenal of supportive measures to combat severe sepsis and septic shock, and some success, albeit controversial, has been achieved by using low doses of corticosteroids or recombinant human activated protein C. However, a truly effective mediator-directed specific treatment has not been developed yet. Treatment with low doses of corticosteroids or with recombinant human activated protein C remains controversial and its success very limited. Attempts to treat shock by blocking LPS, TNF or IL-1 were unsuccessful, as were attempts to use interferon-gamma or granulocyte colony stimulating factor. Inhibiting nitric oxide synthases held promise but met with considerable difficulties. Scavenging excess nitric oxide or targeting molecules downstream of inducible nitric oxide synthase, such as soluble guanylate cyclase or potassium channels, might offer other alternatives. |
| 2008 | Effect of the administration rate on the biological responses to a fixed dose of endotoxin in the anesthetized pig. | Shock | There have been difficulties to demonstrate a relationship between endotoxin concentration and clinical response. One hypothesis for this difficulty might be that a fast increase in endotoxin concentration elicits a stronger biological response than a more gradual one of the same dose. The aim of the present study was to investigate the existence of such a response. Eighteen randomized pigs were given the same amount of endotoxin either with an initial infusion rate of 4 microg kg(-1) h(-1), which after 1 h was tapered to 0.5 microg kg(-1) h(-1), and after 2 h to 0.063 microg kg(-1) h(-1) (group I), or with a reverse escalating order with the lowest infusion rate given first (group II). After 3 h, the endotoxin infusion was stopped, and the pigs were observed for another 3 h. The responses in TNF-alpha, core temperature, leukocytes, platelets, MAP, left ventricular stroke work index, mixed venous saturation, base excess, pH, and pulmonary compliance were greater in group I than in group II, whereas the IL-6 response did not differ between groups. The biological responses of inflammation, hypotension, hypoperfusion, and organ dysfunction are increased if the organism is exposed to a fixed amount of endotoxin more quickly. |
| 2007 | Prognosis of community acquired pneumonia (CAP): value of triggering receptor expressed on myeloid cells-1 (TREM-1) and other mediators of the inflammatory response. | Cytokine | TREM-1 is an activating receptor expressed on the surface of neutrophils and mature monocytes when stimulated by bacteria or fungi, leading to amplification of the inflammatory response. Our objective is to analyze the prognostic value of serum sTREM-1 levels and other mediators of the inflammatory response, in patients hospitalized for CAP, and to compare its prognostic value with those of advanced age, pneumonia severity scores, Charlson index, nutritional status and severity of sepsis.We included 226 patients with CAP, 145 males and 81 females, median age of 74 years. The following tests were performed: arterial blood gases and chest radiography, nutritional assessment, assessment of the severity of the sepsis, Pneumonia Severity Index (PSI) and CURB-65, and mediators of inflammation: TNF alfa, IL-6, IL-10, IL-1ra, LBP, sCD14, CRP, and sTREM-1. Mortality during admittance was defined as the sole end point.Twenty-eight of the two-hundred and twenty-six patients died (12.4%). On univariate analysis advanced age, dehydration, increased Na, low BMI, handgrip strength, serum albumin, prealbumin, IGF-1, lymphocyte count, conscious drowsiness, tachypnea, decreased PaO2, hypotension, creatinine, ASAT, LDH, severity of sepsis, a high PSI or CURB65, TNFalpha, IL-6, IL-10, IL-1ra, and sTREM-1 were related to mortality. Variables with an independent value were IGF-1, CURB-65, TREM-1, advanced age and IL-6.This study confirms the usefulness of TREM-1 in the diagnosis and prognosis of patients with CAP, which is independent of advanced age, other inflammation markers such as IL-6, severity index for CAP such as CURB-65 or PSI, severity of sepsis and nutritional status including IGF-1. |
| 2007 | The transient receptor potential vanilloid 1 (TRPV1) receptor protects against the onset of sepsis after endotoxin. | FASEB J | Transient potential vanilloid 1 (TRPV1) receptor is an ion channel receptor primarily localized on sensory nerves and activated by specific stimuli to initiate and amplify pain and inflammation, as typified by murine models of scald and arthritis. Little is known of the role of TRPV1 in sepsis, an infective disease associated with inflammation. Through use of a sublethal murine model of lipopolysaccharide-induced peritoneal sepsis, we provide novel evidence that genetic deletion of TRPV1 leads to an enhanced onset of various pathological components of systemic endotoxemia. Paired studies of TRPV1 knockout (KO) and wild-type mice demonstrate significantly enhanced hypotension (56+/-2% vs. 38+/-6% decrease in blood pressure, n=12), hypothermia (13+/-3% vs. 7+/-1% decrease in core temperature, n=6), and peritoneal exudate mediator levels (TNF-alpha, 0.78+/-0.2 vs. 0.38+/-0.1 ng/ml; nitrite, for NO, 35+/-10 vs. 15+/-3 microM; n=8) in TRPV1 KO mice, indicating loss of protective effect. Findings correlated with liver edema and raised plasma levels of aspartate aminotransferase in TRPV1 KO mice. These data suggest that TRPV1 may play an important regulatory role in sepsis independent of the major sensory neuropeptide substance P. The findings are relevant to developing strategies that increase the beneficial, and reduce the harmful, components of sepsis to prevent and treat this often fatal condition. |
| 2007 | [Relationship between hydrogen sulfide and myocardial damage in endotoxemic rats]. | Sheng Li Xue Bao | To investigate the changes and role of hydrogen sulfide (H2S) in myocardial damage in endotoxemic rats, a rat model of endotoxemia induced by injection of lipopolysaccharide (LPS) was developed. Male Wistar rats were divided into four groups: control group, LPS group, LPS + propargylglycine (PPG, a metabolic enzyme inhibitor of H2S) group and LPS + NaHS (H2S donor) group. The mean arterial pressure (MAP) of rats within 4 h was observed, TNF-alpha and H2S contents in plasma, TNF-alpha and H2S contents, lactate dehydrogenase (LDH) and myeloperoxidase (MPO) activity in cardiac muscles were determined. The morphological structure of cardiac muscle was observed. Administration of LPS caused a sustained fall in MAP within 4 h, and significant increases in TNF-alpha and H2S contents in plasma (P<0.05). Plasmic H2S content was negatively correlated with MAP (r = -0.936, -0.913 and -0.908 at 1, 2 and 4 h, respectively, P<0.05). LPS also induced increases in TNF-alpha and H2S contents, LDH and MPO activity in cardiac muscles and myocardial damage. Treatment with PPG reduced the increases in TNF-alpha and H2S contents in plasma, TNF-alpha and H2S contents, LDH and MPO activity in cardiac muscles, ameliorated the hypotensive effect and myocardial damage caused by LPS administration (P<0.05). However, treatment with NaHS increased TNF-alpha and H2S contents in plasma, TNF-alpha and H2S contents, LDH and MPO activity in cardiac muscles, and aggravated the hypotensive action and tissue injuries caused by LPS administration (P<0.05). It is suggested that hypotension and myocardial damage in endotoxemic rats are partly induced by increase in H2S content. |
| 2007 | Cutting edge: Essential role of hypoxia inducible factor-1alpha in development of lipopolysaccharide-induced sepsis. | J Immunol | Sepsis, the leading cause of death in intensive care units, reflects a detrimental host response to infection in which bacteria or LPS act as potent activators of immune cells, including monocytes and macrophages. In this report, we show that LPS raises the level of the transcriptional regulator hypoxia-inducible factor-1alpha (HIF-1alpha) in macrophages, increasing HIF-1alpha and decreasing prolyl hydroxylase mRNA production in a TLR4-dependent fashion. Using murine conditional gene targeting of HIF-1alpha in the myeloid lineage, we demonstrate that HIF-1alpha is a critical determinant of the sepsis phenotype. HIF-1alpha promotes the production of inflammatory cytokines, including TNF-alpha, IL-1, IL-4, IL-6, and IL-12, that reach harmful levels in the host during early sepsis. HIF-1alpha deletion in macrophages is protective against LPS-induced mortality and blocks the development of clinical markers including hypotension and hypothermia. Inhibition of HIF-1alpha activity may thus represent a novel therapeutic target for LPS-induced sepsis. |
| 2007 | Human umbilical cord blood-derived CD34+ cells cause attenuation of multiorgan dysfunction during experimental heatstroke. | Shock | Multiorgan dysfunction ensuing from severe heatstroke includes hypotension, hepatic and renal failure, hypercoagulable state, activated inflammation, and cerebral ischemia and injury. We attempted to assess whether human umbilical cord blood-derived CD34+ cell therapy improves survival during experimental heatstroke by attenuating multiorgan dysfunction. Anesthetized rats, immediately after the onset of heatstroke, were divided into 2 major groups and given CD34- or CD34+ cells (1 x 10(5)-5 x 10(5)/mL/kg body weight) i.v. They were exposed to ambient temperature of 43 degrees C to induce heatstroke. Another group of rats were exposed to room temperature (26 degrees C) and used as normothermic controls. Hypotension, hepatic and renal failure (evidenced by increased serum urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase levels in plasma), hypercoagulable state (evidenced by increased prothrombin time, activated partial thromboplastin time, and D-dimer, and decreased platelet count and protein C in plasma), activated inflammation (evidence by increased TNF-alpha levels in serum), and cerebral dysfunction (evidenced by intracranial hypertension, cerebral hypoperfusion and hypoxia, and cerebral ischemia and injury) were monitored. When the CD34- cell-treated or untreated rats underwent heat stress, their survival time values were found to be 19 to 23 min. Resuscitation with CD34+ cells significantly improved survival time (duration, 63-291 min). As compared with normothermic controls, all CD34- cell-treated heatstroke animals displayed hypotension, hepatic and renal failure, hypercoagulable state, activated inflammation, and cerebral ischemia and injury. However, CD34+ cell therapy significantly caused attenuation of all the above-mentioned heatstroke reactions. In addition, the levels of IL-10 in plasma and glial cell line-derived neurotrophic factors in brain were all significantly increased after CD34+ cell therapy during heatstroke. Our data indicate that CD34+ cell therapy may resuscitate persons who had a heatstroke by reducing multiorgan dysfunction or failure. |
| 2007 | Exposure to bacterial DNA before hemorrhagic shock strongly aggravates systemic inflammation and gut barrier loss via an IFN-gamma-dependent route. | Ann Surg | To investigate the role of bacterial DNA in development of an excessive inflammatory response and loss of gut barrier loss following systemic hypotension.Bacterial infection may contribute to development of inflammatory complications following major surgery; however, the pathogenesis is not clear. A common denominator of bacterial infection is bacterial DNA characterized by unmethylated CpG motifs. Recently, it has been shown that bacterial DNA or synthetic oligodeoxynucleotides containing unmethylated CpG motifs (CpG-ODN) are immunostimulatory leading to release of inflammatory mediators.Rats were exposed to CpG-ODN prior to a nonlethal hemorrhagic shock. The role of interferon-gamma (IFN-gamma) was investigated by administration of anti IFN-gamma antibodies.Exposure to CpG-ODN prior to hemorrhagic shock significantly augmented shock-induced release of IFN-gamma, tumor necrosis factor-alpha (TNF-alpha) (P < 0.05), interleukin (IL)-6 (P < 0.05), and nitrite levels (P < 0.05), while there was a defective IL-10 response (P < 0.05). Simultaneously, expression of Toll-like receptor (TLR) 4 in the liver was markedly enhanced. Furthermore, intestinal permeability for HRP significantly increased and bacterial translocation was enhanced in hemorrhagic shock rats pretreated with CpG-ODN. Interestingly, inhibition of IFN-gamma in CpG-treated animals reduced TNF-alpha (P < 0.05), IL-6 (P < 0.05), nitrite (P < 0.05), and intestinal permeability following hemorrhagic shock (P < 0.05) and down-regulated expression of TLR4.Exposure to bacterial DNA strongly aggravates the inflammatory response, disrupts the intestinal barrier, and up-regulates TLR4 expression in the liver following hemorrhagic shock. These effects are mediated via an IFN-gamma-dependent route. In the clinical setting, bacterial DNA may be important in development of inflammatory complications in surgical patients with bacterial infection. |
| 2007 | Differential roles of p55 and p75 tumor necrosis factor receptors on stretch-induced pulmonary edema in mice. | Am J Physiol Lung Cell Mol Physiol | Ventilator-induced lung injury plays a crucial role in the outcome of patients with acute lung injury. Previous studies have shown a role for the cytokine tumor necrosis factor-alpha (TNF) in stretch-induced alveolar neutrophil recruitment, but the involvement of TNF in stretch-induced pulmonary edema is unclear. We investigated the effects of TNF through its individual p55 and p75 receptors on early pulmonary edema formation during high stretch ventilation, before neutrophil infiltration. Anesthetized wild-type or TNF receptor single/double knockout mice were ventilated with high tidal volume ( approximately 38 ml/kg) for 2 h or until they developed arterial hypotension. Pulmonary edema was assessed by physiological parameters including respiratory mechanics and blood gases, and by lavage fluid protein, lung wet:dry weight ratio, and lung permeability measurements using fluorescence-labeled albumin. High stretch ventilation in wild-type and TNF receptor double knockout animals induced similar pulmonary edema, and only 25-30% of mice completed the protocol. In contrast, the p55 receptor knockout mice were strongly protected from edema formation, with all animals completing the protocol. Myeloperoxidase assay indicated that this protective effect was not associated with decreased pulmonary neutrophil sequestration. The p75 receptor knockout mice, however, displayed increased susceptibility to edema formation, and no animals survived the full 2 h. These results demonstrate a novel role for TNF signaling (independent from its effects on neutrophil recruitment) specifically through the p55 receptor, in promoting high stretch-induced pulmonary edema, whereas p75 signaling may play an opposing role. |
| 2007 | Survival of TNF toxicity: dependence on caspases and NO. | Arch Biochem Biophys | Tumor necrosis factor (TNF) is an endogenous pro-inflammatory cytokine, implicated in pathologies such as rheumatoid arthritis and septic shock. It was originally discovered as a factor with extraordinary antitumor activity, but its shock-inducing properties still prevent its systemic use in cancer. Clinical trials revealed hypotension as the major dose-limiting factor of TNF toxicity. When administered to mice, TNF provokes a lethal shock syndrome, where cardiovascular collapse is centrally orchestrated by nitric oxide (NO). Nevertheless, NO synthase (NOS) inhibition in animal models and septic shock patients could not improve and even aggravated outcome, suggesting a bivalent role for NO. Lymphocyte and enterocyte apoptosis has been described in septic, endotoxemic, or TNF-treated animals, as well as in septic patients. In this review, we describe our recent studies on the role of NO and caspases in TNF-induced shock in mice. In summary, we have found that both NO and caspases may exert unexpected and dual functions during TNF shock. Whereas excessive NO production provokes lethal hypotension, it also has an important anti-oxidant function, protecting organs from oxidative stress and lipid peroxidation. In addition, our results also indicate that caspases may exert an important endogenous negative feedback on oxidative stress as well. |
| 2007 | Regulation of renal sodium transporters during severe inflammation. | J Am Soc Nephrol | Sepsis-associated acute renal failure is characterized by decreased GFR and tubular dysfunction. The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration and increased fractional sodium excretion is poorly understood. This study investigated the regulation of renal sodium transporters during severe inflammation in vivo and in vitro. Injection of high-dosage LPS reduced BP and GFR, increased fractional sodium excretion, and strongly decreased the expression of Na(+)/H(+)-exchanger, renal outer medullary potassium channel, Na(+)-K(+)-2Cl(-) co-transporter, epithelial sodium channel, and Na(+)/K(+)-ATPase in mice. Also, injection of TNF-alpha, IL-1beta, or IFN-gamma decreased renal function and expression of renal sodium transporters. LPS-induced downregulation of sodium transporters was not affected in cytokine-knockout mice. However, supplementary glucocorticoid treatment, which inhibited LPS-induced increase of tissue cytokine concentrations, attenuated LPS-induced renal dysfunction and downregulation of tubular sodium transporters. Injection of low-dosage LPS increased renal tissue cytokines and downregulated renal sodium transporters without arterial hypotension. In vitro, in cortical collecting duct cells, cytokines also decreased expression of renal outer medullary potassium channel, epithelial sodium channel, and Na(+)/K(+)-ATPase. Renal hypoperfusion by renal artery clipping did not influence renal sodium transporter expression, in contrast to renal ischemia-reperfusion injury, which depressed transporter expression. These findings demonstrate downregulation of renal sodium transporters that likely accounts for tubular dysfunction during inflammation. These data suggest that alteration of renal sodium transporters during LPS-induced acute renal failure is mediated by cytokines rather than renal ischemia. However, in a complex in vivo model of severe inflammation, the possible presence and influence of renal hypoperfusion and reperfusion on the expression of renal sodium transporters cannot be completely excluded. |
| 2007 | Cytokine-mediated regulation of urea transporters during experimental endotoxemia. | Am J Physiol Renal Physiol | Acute renal failure (ARF) is a frequent complication of sepsis and has a high mortality. Sepsis-induced ARF is known to be associated with significant impairment of tubular capacity. However, the pathogenesis of endotoxemic tubular dysfunction with failure of urine concentration is poorly understood. Urea plays an important role in the urinary concentrating mechanism and expression of the urea transporters UT-A1, UT-A2, UT-A3, UT-A4, and UT-B is essential for tubular urea reabsorption. The present study attempts to assess the regulation of renal urea transporters during severe inflammation in vivo. Lipopolysaccharide-(LPS)-injected mice presented with reduced glomerular filtration rate, fractional urea excretion, and inner medulla osmolality associated with a marked decrease in expression of all renal urea transporters. Similar alterations were observed after application of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, or IL-6. LPS-induced downregulation of urea transporters was not affected in knockout mice with deficient TNF-alpha, IL-receptor-1, IFN-gamma, or IL-6. Glucocorticoid treatment inhibited LPS-induced increases of tissue TNF-alpha, IL-1beta, IFN-gamma, or IL-6 concentration, diminished LPS-induced renal dysfunction, and attenuated the downregulation of renal urea transporters. Renal ischemia induced by renal artery clipping did not influence the expression of urea transporters. Our data demonstrate that renal urea transporters are downregulated by severe inflammation, which likely accounts for tubular dysfunction. Furthermore, they suggest that the downregulation of renal urea transporters during LPS-induced ARF is mediated by proinflammatory cytokines and is independent from renal ischemia because of sepsis-induced hypotension. |
| 2007 | Effects of continuous high-volume hemofiltration on experimental severe acute pancreatitis in pigs. | Pancreas | To compare the effects of different doses of hemofiltration on severe acute pancreatitis (SAP) in pigs.The animal model of SAP was produced by intraductal injection of sodium taurocholate and trypsin. Animals in group 1 served as SAP control. Animals in group 2 received (20 mL/kg per hour) continuous low-volume hemofiltration (LVHF), and animals in group 3 received (100 mL/kg per hour) continuous high-volume hemofiltration (HVHF) immediately after the induction of SAP. After the instrumentation of the animals by arterial and Swan-Ganz catheters, hemodynamic indexes were monitored intermittently at different times. The rectal temperature and the concentration of amylase and cytokines in serum were measured at the same time.The survival time of HVHF group was significantly prolonged (P < 0.01). The initial elevation of body temperature and the hypothermia in the late course of experiments were significantly ameliorated by HVHF (P < 0.01). Six hours after the induction of pancreatitis, the urine output of animals in HVHF group was obviously higher than that in control group (P < 0.05), which stayed behind 36 hours later (P < 0.05). The major hemodynamic finding was that pancreatitis-induced hypotension was significantly attenuated by HVHF (P < 0.01). The development of hyperdynamic circulatory failure was simultaneously attenuated, as reflected by a limited increase in CI, an attenuated decrease in systemic vascular resistance index. Plasma amylases in the HVHF group were significantly lower than those in control and LVHF groups (P < 0.01). The serum concentrations of cytokines such as tumor necrosis factor alpha (TNF-alpha), interleukin (IL) 6, and IL-10 all decreased significantly in treatment groups (P < 0.01), and those of HVHF group were less significant than the HVHF group (P < 0.01).The HVHF was associated with a better hemodynamic profile, a less hyperkinetic state, and more prolonged survival than that of LVHF, which may result from the HVHF that can remove the inflammatory cytokines more efficiently. |
| 2007 | Effects of the treatment with glibenclamide, an ATP-sensitive potassium channel blocker, on intestinal ischemia and reperfusion injury. | Eur J Pharmacol | Intestinal ischemia and reperfusion injury is dependent on the recruitment and activation of neutrophils. Glibenclamide, an ATP-sensitive potassium channel (K(ATP)) blocker, has been shown to suppress neutrophil migration and chemotaxis during acute inflammatory responses by a mechanism dependent on its K(ATP) channel blocking activity. In the present study, we evaluated whether the treatment with glibenclamide prevented local, remote and systemic injury following reperfusion of the ischemic superior mesenteric artery in rats. The artery was made ischemic for a period of 30 or 120 min followed by 30 (mild I/R) or 120 (severe I/R) min of reperfusion, respectively. Glibenclamide (0.8 to 20 mg/kg) or vehicle was administered subcutaneously 40 min prior to the reperfusion. Glibenclamide dose-dependently inhibited the reperfusion-associated increase in vascular permeability and neutrophil accumulation in mild I/R. In the severe injury model, glibenclamide inhibited inflammatory parameters, as assessed by Evans blue extravasation, neutrophil influx and haemoglobin content, and the increase in TNF-alpha (tumor necrose factor-alpha) and IL (interleukin)-6 levels in the intestine and lung. The drug did not affect the increase in IL-1beta and IL-10 levels. TEA, a nonselective potassium channel blocker, also inhibited reperfusion injury in both intestine and lungs of animals submitted to mild and severe I/R. Our experiments suggest a role for K(ATP) channels in mediating neutrophil influx and consequent reperfusion-associated injury in rats. The lack of effect of these drugs on the reperfusion-associated hypotension and lethality may limit their usefulness after severe reperfusion injury. |
| 2007 | Protective effect of baicalein against endotoxic shock in rats in vivo and in vitro. | Biochem Pharmacol | Dried roots of Scutellaria baicalensis Georgi (Huang qin) are widely used in traditional Chinese medicine. Baicalein is a major bioactive flavonoid component of H. qin that shows a wide range of biological activities, including antioxidant and anti-inflammatory actions. We evaluated therapeutic effects and possible mechanisms of action of baicalein on circulatory failure and vascular dysfunction during sepsis induced by lipopolysaccharide (LPS; 10 mg/kg, i.v.) in anesthetized rats. Treatment of the rats with baicalein (20 mg/kg, i.v.) significantly attenuated the deleterious hemodynamic changes of hypotension and tachycardia caused by LPS and significantly inhibited the elevation of plasma tumor necrosis factor alpha (TNF-alpha). Baicalein also decreased levels of inducible nitric oxide synthase (iNOS) and the overproduction of NO and superoxide anions caused by LPS. It also increased the survival rate of ICR mice (25-30 g) challenged by LPS (60 mg/kg). Moreover, infiltration of neutrophils into the liver and lungs of rats 6h after treatment with LPS was also reduced by baicalein. To investigate the mechanism of action of baicalein on sepsis, RAW 264.7 cells were used as a model. Baicalein inhibited iNOS protein production, and suppressed LPS-induced degradation of IkappaBalpha, the formation of a nuclear factor kappa B (NF-kappaB)-DNA complex and NF-kappaB-dependent reporter gene expression. Thus, the therapeutic effects of baicalein were associated with reductions in TNF-alpha and superoxide anion levels during sepsis. The inhibitory effects of baicalein on iNOS production may be mediated by inhibition of the activation of NF-kappaB. Baicalein may thus prove a potential agent against endotoxemia. |
| 2006 | Effects of ketamine on proinflammatory cytokines and nuclear factor kappaB in polymicrobial sepsis rats. | World J Gastroenterol | To explore the effects of ketamine on hemo-dynamics, plasma proinflammatory cytokine (TNF-alpha and IL-6) levels and nuclear factor kappa B (NF-kappaB) activation during polymicrobial sepsis.Male Sprague-Dawley rats were subjected to cecal ligation and puncture (CLP) or sham operation. The rats were randomly assigned into four equal groups: sham CLP group, CLP group, ketamine (KT) I group and KT II group. Thirty minutes before CLP, ketamine (5 mg/kg per hour and 10 mg/kg per hour, respectively) was infused continuously through the left femoral vein cannula in KT I group or KT II group. Sham CLP group and CLP group received 0.9% saline only (5 mL/kg per hour). The right femoral artery was cannulated to monitor mean arterial pressure (MAP) and heart rates (HR),and draw blood samples. The proinflammatory cytokine (TNF-alpha and IL-6) levels of plasma were measured using enzyme-linked immunosorbent assays (ELISA). The hepatic NF-kappaB activation was determined by Western blot and HPIAS 2000 image analysis system. Twenty hours after CLP, the rats were killed by right femoral artery phlebotomization.CLP produced progressive hypotension, and a first increase followed by a decrease in HR. The hypotension was prevented, and the HR was slightly steady in ketamine treated rats. TNF-alpha levels of plasma reached a peak value at 2 h after CLP. Ketamine (KT I group or KT II group) caused a significant decrease compared with CLP group at 2, 5 and 9 h time points after CLP (14.3 +/- 1.9 vs 4.3 +/- 0.9, 9.7 +/- 1.4 vs 4.3 +/- 0.9; 9.3 +/- 1.5 vs 4.3 +/- 0.9, 8.7 +/- 1.4 vs 4.3 +/- 0.9; 6.0 +/- 1.5 vs 5.0 +/- 1.7, 5.3 +/- 0.8 vs 5.0 +/- 1.7; P < 0.01, respectively). The IL-6 levels of plasma firstly ascended and then descended in CLP group, and reached a peak value at 9 h after CLP. Ketamine (KT I group or KT II group) caused a significant decrease compared with CLP group at 5, 9 or 20 h after CLP (135.0 +/- 52.6 vs 60.0 +/- 16.3, 112.5 +/- 52.6 vs 60.0 +/- 16.3; 410.0 +/- 68.7 vs 62.5 +/- 12.5, 250.0 +/- 28.0 vs 62.5 +/- 12.5; 320.0 +/- 25.9 vs 52.5 +/- 10.1, 215.0 +/- 44.6 vs 52.5 +/- 10.1; P < 0.05, respectively). The IL-6 levels of plasma in KT II group were lower than those of KT I group at 9 h after CLP (250.0 +/- 28.0 vs 410.0 +/- 68.7; P < 0.05). In addition, CLP increased hepatic NF-kappaB expression compared with sham CLP. Ketamine suppressed NF-kappaB activation in a dose-dependent manner at 4 h after CLP (237.7 +/- 3.5 vs 246.9 +/- 3.1; P < 0.05).Ketamine stabilizes the hemodynamics, attenuates the proinflammatory cytokine responses, and inhibits hepatic NF-kappaB activation. These findings suggest that ketamine has protective effects against polymicrobial sepsis in rats. |
| 2006 | Tumor necrosis factor-alpha genetic predisposing factors can influence clinical severity in nephropathia epidemica. | Viral Immunol | Severe human infection with Hantavirus is characterized by high fever, cold chills, thrombocytopenia, arterial hypotension, acute renal failure, and/or adult respiratory distress syndrome (ARDS)-like pulmonary involvement, but the clinical course varies greatly between individuals. We investigated whether genetically determined differences in tumor necrosis factor (TNF)-alpha production can influence the severity of Hantavirus disease. We studied a TNF-alpha single-nucleotide promoter polymorphism (SNP) at position -238 (a guanine [G]-to-adenine [A] transition) and ex vivo TNF-alpha production in a recall study of 36 Belgian patients who had a serologically proven form of Puumala virus-induced Hantavirus infection with the kidney as main target organ. In our study, the highest creatinine levels were found in patients with the lowest ex vivo TNF-alpha production. Creatinine levels correlated inversely with TNF-alpha production (R = -0.35, p < 0.05). The number of thrombocytes was significantly lower in patients with the GA-238 genotype (low TNF-alpha producers) compared with patients with the GG-238 genotype. In our study, genetically determined low production of TNF-alpha was associated with some parameters indicating a more severe clinical course of Puumala Hantavirus infection in humans, possibly by impaired activation of TNF-alpha-dependent antiviral mechanisms, which could in turn result in decreased clearance of Hantavirus. |
| 2006 | Oxidative stress and septic shock: metabolic aspects of oxygen-derived free radicals generated in the liver during endotoxemia. | FEMS Immunol Med Microbiol | This review describes the role of oxidative stress caused by endotoxin challenge in sepsis or septic shock symptoms. We observed that endotoxin injection resulted in lipid peroxide formation and membrane damage (near 60-150 kDa) in the livers of experimental animals, causing decreased levels of scavengers or quenchers of free radicals. The administration of alpha-tocopherol completely prevented injury to the liver plasma membrane caused by endotoxin, and suggested that lipid peroxidation by free radicals might occur in a tissue ischemic state, probably by disseminated intravascular coagulation (DIC), in endotoxemia. In mice, depression of Ca(2+)-ATPase activity in the liver plasma membrane may contribute to the membrane damage caused by endotoxin, and the increase of [Ca(2+)](i) in the liver cytoplasm may partially explain the oxidative stress that occurs in endotoxemia. It seems that endotoxin-induced free radical formation is regulated by Ca(2+) mobilization. Moreover, we have suggested that the oxidative stress caused by endotoxin may be due, at least in part, to the changes in endogenous zinc or selenium regulation during endotoxemia. Interestingly, the extent of TNF-alpha-induced oxidative stress may be the result of a synergism between TNF-alpha and gut-derived endotoxin. It is likely that bacterial or endotoxin translocation plays a significant role in TNF-alpha-induced septic shock. On the other hand, although nitric oxide (NO) has been implicated in the pathogenesis of vascular hyporesponsiveness and hypotension in septic shock in our experimental model, it is unlikely that NO plays a significant role in liver injury caused by free radical generation in endotoxemia. |
| 2006 | Antithrombin reduces endotoxin-induced hypotension by enhancing pulmonary sensory neuron activation in rats. | Thromb Haemost | We recently demonstrated that activation of the pulmonary sensory neurons plays a critical role in prevention of endotoxin-induced shock by releasing calcitonin gene-related peptide (CGRP) in rats. CGRP increased the endothelial production of prostacyclin (PGI(2)) in the lungs, thereby preventing endotoxin-induced shock response by inhibiting tumor necrosis factor-alpha (TNF-alpha) production. Since antithrombin (AT) enhances sensory neuron activation, we hypothesized that AT might reduce endotoxin-induced hypotension by enhancing the activation of pulmonary sensory neurons in rats. We examined this possibility using a rat model of endotoxin shock. AT-induced effects including reduction of hypotension (n = 5) and inhibition of induction of iNOS (n = 4 or 5) and TNF- alpha (n = 5) in the lungs of endotoxin-treated animals were completely reversed by pretreatment with capsazepine (CPZ) (n = 4 or 5), a vanilloid receptor antagonist, or CGRP(8-37), a CGRP receptor antagonist (n = 4 or 5). AT enhanced endotoxin-induced increases in lung tissue levels of CGRP (n = 4), but this effect of AT was not seen in animals pretreated with CPZ (n = 4). CGRP produced therapeutic effects (n = 5) similar to those induced by AT, and such therapeutic effects were completely abrogated by pretreatment with indomethacin (n = 4). AT increased CGRP release from cultured dorsal root ganglion neurons only in the presence of anandamide (n = 5), and AT-induced increase in CGRP release was not observed in the presence KT5720, an inhibitor of protein kinase A (n = 5). AT markedly increased intracellular levels of cAMP in the presence of anandamide (n = 5). These results strongly suggested that AT might reduce endotoxin-induced hypotension in rats by enhancing activation of sensory neurons via activation of protein kinase A. |
| 2006 | Activation of the cholinergic anti-inflammatory pathway reduces NF-kappab activation, blunts TNF-alpha production, and protects againts splanchic artery occlusion shock. | Shock | The cholinergic anti-inflammatory pathway has not yet been studied in splanchnic artery occlusion (SAO) shock. We investigated whether electrical stimulation (STIM) of efferent vagus nerves suppresses the inflammatory cascade in SAO shock. Animals were subjected to clamping of the splanchnic arteries for 45 min, followed by reperfusion. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham-operated animals were used as controls. Two minutes before the start of reperfusion, rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Application of constant voltage pulses to the caudal vagus ends (STIM: 5 V, 2 ms, 6 Hz for 15 min, 5 min after the beginning of reperfusion) increased survival rate (VGX + SAO + Sham STIM = 0% at 4 h of reperfusion; VGX + SAO + STIM = 90% at 4 h of reperfusion), reverted the marked hypotension, inhibited IkappaBalpha liver loss, blunted the augmented nuclear factor-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX + SAO + Sham STIM = 1.0 +/- 1.9 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio; VGX + SAO + STIM = 0.3 +/- 0.2 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio), reduced plasma TNF-alpha (VGX + SAO + Sham STIM = 118 +/- 19 pg/mL; VGX + SAO + STIM = 39 +/- 8 pg/mL), ameliorated leukopenia, and decreased leukocyte accumulation, as revealed by means of myeloperoxidase activity in the ileum (VGX + SAO + Sham STIM = 7.9 +/- 1 U/g tissue; VGX + SAO + STIM = 3.1 +/- 0.7 U/g tissue) and in the lung (VGX + SAO + Sham STIM = 8.0 +/- 1.0 U/g tissue; VGX + SAO + STIM = 3.2 +/- 0.6 U/g tissue). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation. Our results show a parasympathetic inhibition of nuclear factor-kappaB and TNF-alpha in SAO shock. |
| 2006 | [Effects of hydrocortisone on circulating and intramyocardial inflammatory mediators in severe septic rats with myocardial injury induced by Escherichia coli]. | Zhonghua Er Ke Za Zhi | Severe sepsis and septic shock remain the most common cause of death in intensive care units. The main causes of death in sepsis are the cardiac dysfunction and hypotension resistant to cateolamines. The prevalence of relative adrenal insufficiency in severe sepsis and septic shock was estimated at about 32%-51%. Several meta-analysis demonstrated that high-dose glucocorticoids decreased survival during sepsis, while stress doses of corticosteroids may benefit these patients. The exact reason for such widely divergent outcome produced by different doses of corticosteroid is still not understood. Therefore, the study was undertaken to observe the effects of different doses of hydrocortisone (HC) on circulating and intramyocardial inflammatory mediators in severe septic rats with myocardial injury induced by Escherichia coli (E. coli).The model was established by two injections of inactivated E. coli Forty male Wistar rats were randomly divided into five groups: high-dose of HC group (150 mg/kg), medium-dose group (20 mg/kg), low-dose group (6 mg/kg), model group (NS substituted for HC), and control group (NS for E. coli and HC). Each group had eight rats. After 2 hours of treatment, specimens were collected to measure serum cardiac troponin I (cTnI), tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), nitric oxide (NO) and total NO synthase (NOS). NO and total NOS in myocardial homogenate were also detected. The expression of inducible NOS (iNOS) of myocytes was investigated.All the above-mentioned markers in model group significantly higher than those in control group. After HC injection, serum cTnI concentrations in low-dose group decreased to normal values compared to that of model group, while in another two HC groups, the concentrations were higher than those in model group. TNF-alpha level was not significantly influenced. But IL-1beta level declined to normal values, being prominent in low-dose HC group. Neither high-dose nor middle-dose HC could lower serum NO or total NOS, but low-dose HC could greatly inhibit both NO and NOS levels (P < 0.05). There was no significant difference in the level of NO and total NOS of myocardial homogenate between left and right ventricles. There was no iNOS expression by normal myocardium, while the expression in model group was significantly increased. After HC injection, the iNOS expressions by myocardium in three HC groups were weaker than those in model group. The intensity of iNOS signals became weak with the decrease in HC dose.Different doses of HC might exert different effects on circulating and intramyocardial inflammatory mediators in severely septic rats with myocardial injury induced by E. coli. Low-dose HC could significantly inhibit such mediators as well as iNOS expression by cardiomyocytes. The results suggest that low dose HC exert protective effect on myocardial injury of severely septic rats. |
| 2006 | N-Allylsecoboldine as a novel agent prevents acute renal failure during endotoxemia. | Eur J Pharmacol | Blockades of cytokine and oxygen radicals release are considered to be beneficial in reducing multiple organ injury and increasing the survival rate in sepsis/septic shock. Thus, we examined the protective efficacy of N-allylsecoboldine, a secoaporphine derivative with antioxidant and alpha1-adrenoceptor blocking activities, in rats treated with endotoxin (E. coli lipopolysaccharide, LPS). Pretreatment of LPS-treated rats with N-allylsecoboldine significantly attenuated the late-phase hypotension, hypoglycemia and incremental plasma tumor necrosis factor (TNF)-alpha. Overproduction of plasma nitrate in endotoxemia was not changed but the continuous decrease of urinary nitrate appeared to be partially ameliorated by N-allylsecoboldine. However, N-allylsecoboldine inhibited the inducible nitric oxide synthase (iNOS) protein expression in the renal cortex of endotoxemic rats. N-allylsecoboldine also improved the endotoxemia-induced organ injury as demonstrated from the conspicuous recovery of marker enzymes in the LPS-treated rats. Endotoxemia was associated with renal dysfunctions as indicated by decreases in renal blood flow, urinary potassium excretion, and renal nitrate clearance. However, pretreatment with N-allylsecoboldine showed significant alleviation of these renal dysfunctions. In addition, a lower dose of N-allylsecoboldine ameliorated the mortality of LPS-treated mice. This study demonstrates N-allylsecoboldine's ability to avail against acute renal failure and increase survival rate during endotoxemia. These beneficial effects may be attributed to the inhibition of iNOS expression, TNF-alpha production, and free radical scavenging activities. However, the role of alpha1-adrenoceptor antagonism for N-allylsecoboldine in sepsis remains unclear. |
| 2006 | A novel adsorbent of circulating bacterial toxins and cytokines: the effect of direct hemoperfusion with CTR column for the treatment of experimental endotoxemia. | Crit Care Med | The current study examined the ability of a new adsorbent, CTR, to remove enterotoxins, toxic shock syndrome toxin-1 (TSST-1), and cytokines from blood and/or serum in vitro and the effects of the extracorporeal treatment with CTR column on mortality rate and inflammatory responses to endotoxic shock in vivo.Laboratory investigation.University and company experimental laboratory.CTR is composed of porous cellulose beads to which a hydrophobic organic compound with a hexadecyl alkyl chain has been covalently bound to the surface as a ligand. Human/bovine serum and human blood samples in vitro and Male Wistar rats were used.CTR's ability to adsorb bacterial toxins and cytokines related to sepsis in serum and/or blood was examined with an in vitro batch adsorption protocol. In vivo, male Wistar rats were anesthetized and assigned to one of three groups (n=14 per group): Escherichia coli endotoxin (15 mg/kg intravenously) alone (endotoxemic), apheresis with control column without CTR for 120 mins (control column), or extracorporeal treatment with CTR column for 120 mins (CTR treatment).With use of the CTR adsorbent, the adsorption rates were 50% to 90% for enterotoxins, TSST-1, and cytokines such as TNF-alpha and interleukin (IL)-6 in the batch tests. In vivo, the mortality rates at 8 hrs after endotoxin injection were 92%, 92%, and 14% for the endotoxemic, control column, and CTR treatment groups, respectively. Hypotension and elevated plasma cytokine concentrations and the infiltration of neutrophils of the lungs were less conspicuous in the CTR treatment group than in the other two groups.CTR, a novel adsorbent, effectively adsorbed small- to middle-sized proteins, such as cytokines, enterotoxins, and TSST-1 in vitro. Direct hemoperfusion apheresis with CTR column reduced mortality and had inhibitory effects on the inflammatory responses during endotoxemia in vivo. These findings suggest that extracorporeal blood purification with CTR column may be available to use for patients with sepsis and/or endotoxemia. |
| 2006 | Disparate IL-1beta and iNOS gene expression in the aorta and pulmonary artery after endotoxemia. | Surg Infect (Larchmt) | Endotoxemia causes paradoxical effects on the systemic and pulmonary vasculature, resulting in systemic hypotension and increased pulmonary artery pressure. The local production of inflammatory mediators may have important effects on vascular tissue function. The purpose of this study was to delineate differences in function and the expression of tissue cytokine genes in the aorta and pulmonary artery after endotoxemia.Thoracic aorta and pulmonary artery branches were isolated from adult Sprague- Dawley rats (n = 4-6/group) 6 h after intraperitoneal injection of lipopolysaccharide (Salmonella typhimurium, 20 mg/kg) or vehicle (1.0 mL of saline). Arteries were suspended in perfused organ baths for measurement of isometric force transduction, and dose-response curves to phenylephrine (0.01-10 micromol/L), acetylcholine (0.01-10 micromol/L), and sodium nitroprusside (0.001-10 micromol/L) were generated. The vascular segments were also assessed for expression of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) by semiquantitative reverse transcriptase- polymerase chain reaction.Endotoxemia resulted in decreased contractility of the aorta (508.63 +/- 81.89 mg vs. 2544.16 +/- 142.05 mg in the vehicle group) and pulmonary artery (352.50 +/- 38.11 mg vs. 535.83 +/- 45.51 mg in the vehicle group) and decreased endothelium-dependent pulmonary artery relaxation (52.86 +/- 5.63% vs. 80.58 +/- 6.39% in the vehicle group). Expression of IL-1beta and iNOS mRNA by the pulmonary artery, but not the aorta, increased significantly in the endotoxintreated animals. Interleukin-6 was increased in both the pulmonary artery and the aorta during endotoxemia, whereas TNF concentrations were unchanged.Endotoxemia may cause aortic hypocontractility and impaired endothelium-dependent pulmonary artery vasorelaxation. Expression of inflammatory genes in vascular tissue may be site-specific and may contribute to the functional derangements associated with sepsis. |
| 2006 | 8. Drug allergy. | J Allergy Clin Immunol | Drug reactions can be considered as being either predictable or unpredictable. A predictable reaction would be the result of the pharmacologic action of the medication. An unpredictable reaction might be idiosyncratic, might be drug intolerance, or might have or imply an immunologic basis, such as being IgE mediated. Immediate reactions that are not IgE mediated can be considered as pseudoallergic (non-IgE-mediated mast cell activation). This review will discuss allergic and immunologic reactions to immunomodulators, penicillins and cephalosporins, sulfonamides, aspirin, and nonselective nonsteroidal anti-inflammatory drugs and consider the serious drug-related conditions of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The field of drug "allergy" has expanded to include adverse reactions associated with immunosuppressive medications, anticytokine therapies, and mAbs. The cytokine release reaction that occurs with anti-CD20 antibody infusions in patients with leukemia and white blood cell counts of greater than 50 x 10(9)/L is associated with high concentrations of TNF, IL-6, and IL-8. Because of the findings of fever, dyspnea, rigors, and hypotension, this reaction resembles the Jarisch-Herxheimer reaction that occurs 60 to 90 minutes after penicillin administration in patients with secondary syphilis. Furthermore, the care of the patient with penicillin allergy has been made more difficult in the absence of the major determinant, penicilloyl-polylysine, in that from 34% to 84% of patients who have positive skin test reactions to penicillin have exclusively positive reactions to the major determinant. SJS and TEN typically are caused by medications within 1 to 8 weeks of initiation of therapy. Evidence for death of the keratinocytes through (1) drug-specific cytotoxicity with the perforin-granzyme B-mediated killing and (2) activation of Fas on keratinocytes have provided explanations for the sloughing of skin. Unfortunately, intravenous immunoglobulin therapy for SJS and TEN has been disappointing. |
| N-acetylcysteine abrogates acute lung injury induced by endotoxin. | Clin Exp Pharmacol Physiol | 1. Acute lung injury (ALI) or acute respiratory distress syndrome is a serious clinical problem with high mortality. N-Acetylcysteine (NAC) is an anti-oxidant and a free radical scavenger. It has been reported recently that NAC ameliorates organ damage induced by endotoxin (lipopolysaccharide; LPS) in conscious rats. The present study was designed to evaluate the effects of NAC on LPS-induced ALI and other changes in anaesthetized rats. 2. Sprague-Dawley rats were anaesthetized with pentobarbital (40 mg/kg, i.p.). Endotracheal intubation was performed to provide artificial ventilation. Arterial pressure and heart rate were monitored. The extent of ALI was evaluated with the lung weight (LW)/bodyweight ratio, LW gain, exhaled nitric oxide (NO) and protein concentration in bronchoalveolar lavage (PCBAL). Haematocrit, white blood cells, plasma nitrate/nitrite, methyl guanidine (MG), tumour necrosis factor (TNF)-alpha and interleukin (IL)-1b were measured. Pathological changes in the lung were examined and evaluated. 3. Endotoxaemia was produced by injection of 10 mg/kg, i.v., LPS (Escherichia coli). Animals were randomly divided into three groups. In the vehicle group, rats received an i.v. drip of physiological saline solution (PSS) at a rate of 0.3 mL/h. The LPS group received an i.v. drip of PSS for 1 h, followed by LPS (10 mg/kg by slow blous injection, i.v., over 1-2 min). Rats in the LPS + NAC group received NAC by i.v. drip at a rate of 150 mg/kg per h (0.3 mL/h) for 60 min starting 10 min before LPS administration (10 mg/kg by slow blous injection, i.v., over 1-2 min). Each group was observed for a period of 6 h. 4. N-Acetylcysteine treatment improved the LPS-induced hypotension and leukocytopenia. It also reduced the extent of ALI, as evidenced by reductions in LW changes, exhaled NO, PCBAL and lung pathology. In addition, NAC diminished the LPS-induced increases in nitrate/nitrite, MG, TNF-a and IL-1b. 5. In another series of experiments, LPS increased the mortality rate compared with the vehicle group (i.v. drip of PSS at a rate of 0.3 mL/h) during a 6 h observation period. N-Acetylcysteine, given 10 min prior to LPS, significantly increased the survival rate. 6. The results of the present study suggest that NAC exerts a protective effect on the LPS-induced ALI. The mechanisms of action may be mediated through the reduction of the production of NO, free radicals and pro-inflammatory cytokines. |
| 2006 | MAP kinase phosphatase 1 controls innate immune responses and suppresses endotoxic shock. | J Exp Med | Septic shock is a leading cause of morbidity and mortality. However, genetic factors predisposing to septic shock are not fully understood. Excessive production of proinflammatory cytokines, particularly tumor necrosis factor (TNF)-alpha, and the resultant severe hypotension play a central role in the pathophysiological process. Mitogen-activated protein (MAP) kinase cascades are crucial in the biosynthesis of proinflammatory cytokines. MAP kinase phosphatase (MKP)-1 is an archetypal member of the dual specificity protein phosphatase family that dephosphorylates MAP kinase. Thus, we hypothesize that knockout of the Mkp-1 gene results in prolonged MAP kinase activation, augmented cytokine production, and increased susceptibility to endotoxic shock. Here, we show that knockout of Mkp-1 substantially sensitizes mice to endotoxic shock induced by lipopolysaccharide (LPS) challenge. We demonstrate that upon LPS challenge, Mkp-1-/- cells exhibit prolonged p38 and c-Jun NH2-terminal kinase activation as well as enhanced TNF-alpha and interleukin (IL)-6 production compared with wild-type cells. After LPS challenge, Mkp-1 knockout mice produce dramatically more TNF-alpha, IL-6, and IL-10 than do wild-type mice. Consequently, Mkp-1 knockout mice develop severe hypotension and multiple organ failure, and exhibit a remarkable increase in mortality. Our studies demonstrate that MKP-1 is a pivotal feedback control regulator of the innate immune responses and plays a critical role in suppressing endotoxin shock. |
| 2006 | The duration of hypotension before the initiation of antibiotic treatment is a critical determinant of survival in a murine model of Escherichia coli septic shock: association with serum lactate and inflammatory cytokine levels. | J Infect Dis | This study was designed to examine the relationship between the timing of antibiotic treatment and both survival rates and hemodynamic/inflammatory correlates of survival in a murine model of Escherichia coli septic shock.Surgical implantation of an E. coli (O18:K1:H7)-laced, gelatin capsule-encased fibrinogen clot was used to generate a bacteremic model of murine septic shock. Survival duration, hemodynamic responses, and circulating serum tumor necrosis factor (TNF)-alpha , interleukin (IL)-6, and lactate levels were assessed in relation to increasing delays in or absence of antibiotic treatment.A critical inflection point with respect to survival occurred between 12 and 15 h after implantation. When initiated at or before 12 h, antibiotic treatment resulted in < or = 20% mortality, but, when initiated at or after 15 h, it resulted in >85% mortality. Physiologically relevant hypotension developed in untreated septic mice by 12 h after implantation. Values for heart rate differed between untreated septic mice and sham-infected control mice by 6 h after implantation, whereas values for cardiac output and stroke volume did not differ until at least 18-24 h after implantation. Antibiotic treatment initiated > or = 12 h after implantation was associated with persistence of increased circulating serum lactate, TNF- alpha , and IL-6 levels.The timing of antibiotic treatment relative to hypotension is closely associated with survival in this murine model of septic shock. Delay in antibiotic treatment results in the persistence of inflammatory/stress markers even after antibiotic treatment is initiated. |
| 2005 | Circulating interferon-gamma and white matter brain damage in preterm infants. | Pediatr Res | The fetal inflammatory response has been suggested as causal in neonatal morbidity. Serial levels of circulating cytokines were evaluated in 74 infants with a mean gestational age (GA) of 27.1 wk. Pro-inflammatory [tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), IL-1 beta, IL-2, IL-6, IL-8, IL-12] [corrected] and modulatory (IL-4, IL-10) cytokines were analyzed from cord blood, and at 6, 24 [corrected] and 72 h postnatal age. Measure of cytokine burden over time was assessed by calculating the area under curve (AUC) for analyzed levels (0-72 h). Premature rupture of membranes (PROM) was associated with higher levels of IL-2 at birth and at 6 h, of IFN-gamma at 6 and 24 h postnatal age and of TNF-alpha at 6 and 24 h. Levels of IFN-gamma at 6, 24, and 72 h were increased in infants developing white matter brain damage (WMD) compared with those without WMD. Infants with arterial hypotension requiring dopamine treatment had an increase in IL-6 with a peak at 6 h of age. Severe intraventricular hemorrhage (IVH) was associated with increase in AUC [(IL-6) and (IL-8), odds ratio (OR) 2.8 and 13.2 respectively], whereas white matter brain damage (WMD) [corrected] was associated with increase in AUC (IFN-gamma; OR, 26.0) [corrected] A fetal immune response with increased postnatal levels of IFN-gamma was associated with development of WMD. PROM was associated with a T-helper 1 cytokine response with increased levels of IFN-gamma. Type of inflammatory response appears of importance for subsequent morbidity. |
| 2005 | Hepatic over-expression of TGF-beta1 promotes LPS-induced inflammatory cytokine secretion by liver cells and endotoxemic shock. | Immunol Lett | Transforming growth factor-beta (TGF-beta) is an important suppressor of inflammation. However, TGF-beta has also been found to promote secretion of inflammatory cytokines, and transgenic mice, which constitutively express TGF-beta in liver, have been found to be more susceptible to endotoxemia. To approach this apparent paradox, we investigated the role of hepatic TGF-beta1 in endotoxemia by utilising inducible TGF-beta1-transgenic mice that express TGF-beta1 under control of the C-reactive protein promoter. In contrast to non-transgenic littermates, administration of lipopolysaccharide (LPS) induced strongly increased expression of TGF-beta and acute phase proteins in the TGF-beta1-transgenic mice. Hepatic TGF-beta1-expression in the transgenic mice started an inflammatory cytokine cascade, marked by increased and prolonged secretion of TNF-alpha and IL-6 by hepatocytes. The inflammatory response of the TGF-beta1-transgenic mice to LPS was associated with high rates of mortality due to endotoxemic shock, marked by systemic hypotension and hypothermia. Endotoxemic shock was primarily mediated by TNF-alpha and IL-6, since inhibitory antibody to TNF-alpha or, more effectively, to IL-6 could reduce mortality in these mice. In conclusion, while TGF-beta-signalling to immune cells may suppress inflammatory effector function, TGF-beta-signalling to liver cells seems to promote LPS-stimulated secretion of inflammatory cytokines and to predispose for lethal endotoxemic shock. |
| 2005 | Exogenous nitric oxide modulates the systemic inflammatory response and improves kidney function after risk-situation abdominal aortic surgery. | J Vasc Surg | Renal impairment is a very frequent complication of aortic surgery requiring prolonged suprarenal clamping, especially if it is associated with previous hemorrhage. The aim of this study was to assess the beneficial effect of the administration of a nitric oxide (NO) donor on renal function through a modulation of the systemic inflammatory response in a model of abdominal aortic surgery.Twenty-five minipigs were divided into five groups. Under anesthesia, the animals were subjected to suprarenal aortic-iliac clamping (for 30 minutes) and bypass with a Dacron-collagen prosthetic graft impregnated in rifampicin, with or without associated hemorrhage (40% of total blood volume). Prophylaxis with cefazolin was implemented. The five groups were (1) the sham group (only aortic dissection), (2) the clamping and bypass (C) group, (3) hemorrhage preclamping and bypass (H+C) group, (4) the same as group C but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (C+NO group), (5) the same as the H+C group but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (H+C+NO group). The following were determined: (1) kidney function (serum creatinine), (2) serum cytokines (tumor necrosis factor alpha [TNF-alpha] and interleukin-10 [IL-10]); (3) neutrophil infiltration (myeloperoxidase [MPO]) in the kidney, (4) oxygen free radicals (superoxide anion [SOA] and superoxide dismutase [SOD]) in the kidney, (5) serum nitrites, (6) soluble and kidney tissue cell adhesion molecule (soluble intercellular adhesion molecule-1 [sICAM-1], soluble vascular cell adhesion molecule-1 [sVCAM-1], intercellular adhesion molecule-1 [ICAM-1], and vascular cell adhesion molecule-1 [VCAM-1]), (7) inducible nitric oxide synthase (iNOS) in the kidney, and (8) nuclear factor-kappaB (NF-kappaB) in the kidney. Determinations were made during ischemia at 15 minutes post-reperfusion; at 24, 48, and 72 hours; and on day 7.The different insults used in the experimental model led to deterioration in kidney function and an increase in the systemic (and renal) inflammatory response at all levels investigated. Treatment with an NO donor, both with and without associated hemorrhage, reduced the inflammatory response at the systemic (TNF-alpha and IL-10) and kidney (MPO, SOA, and SOD) levels, normalizing kidney function. Likewise, exogenous administration of NO improved the excessive production of NO (nitrites) via iNOS. This was also reflected in a reduction in CAMs and of NF-kappaB expression. The hypotension induced by molsidomine was transitory and did not elicit hemodynamic repercussions.In our experimental model, prophylactic treatment with the NO donor molsidomine regulates the systemic inflammatory response and minimizes damage at the kidney level. Clinical Relevance The importance of this article resides in the fact that an experimental study that clarifies the effect of the donors of NO under circumstances as similar as possible to those of the human clinic, such as aortic surgery under hypovolemic shock (ruptured aortic aneurysm) have been little studied, most of these studies being performed in rodents without bypass. Using a model with one or two simultaneous insults (aortic clamping with/without previous hemorrhage) that is very similar to the human clinical situation (abdominal aortic rupture), we confirm the findings of previous work related to the beneficial effects of NO donors. |
| 2005 | Basic fibroblast growth factor alleviates brain injury following global ischemia reperfusion in rabbits. | J Zhejiang Univ Sci B | The aim of this study was to explore the protective effect of basic fibroblast growth factor (bFGF) on brain injury following global ischemia reperfusion and its mechanisms. Brain injury following global ischemia was induced by four vessels occlusion and systemic hypotension. Twenty-four rabbits were randomized into three groups: group A, only dissection of vessels; group B, intravenous infusion of normal saline after reperfusion for 6 h; group C, 30 microg/kg bFGF injected intravenously at the onset of reperfusion, then infused with 10 microg/(kg.h) for 6 h. Serum neuron specific enolase (NSE), S-100B, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-8 (IL-8) were measured before ischemia, 30 min after ischemia, 0.5, 1, 3, 6 h after reperfusion. Brain water content was determined and cerebral histopathological damages were compared. NSE and S-100B were increased 1 h after reperfusion and reached their peaks 6 h after reperfusion, but were much higher in group B than those in group C 3, 6 h after reperfusion. In groups B and C, TNF-alpha was increased after ischemia and IL-1 and IL-8 were increased significantly 0.5 h after reperfusion, then reached their peaks 6 h, 3 h, 6 h after reperfusion respectively. TNF-alpha and IL-8 at the time points of 1 h and 3 h and IL-1 at 3 h and 6 h in group C were correspondingly lower than those in group B. These indices in group A were nearly unchanged. There were less severe cerebral histopathological damages in group C compared with group B, but no difference in brain water content. It could be concluded that bFGF alleviates brain injury following global ischemia and reperfusion by down-regulating expression of inflammatory factors and inhibiting their activities. |
| 2003 | [Screening and characterization of DNA aptamers with hTNF-alpha binding and neutralizing activity]. | Sheng Wu Gong Cheng Xue Bao | Human tumor necrosis factor alpha (hTNF-alpha) is one of the most important inflammatory cytokines that acts as a mediator in inflammatory and immune response and plays a key role in host defense against infection. The over expression of hTNF-alpha is associated with serious consequences, such as shock, hypotension, thrombus, septicemia and even death. It has been implicated in many autoimmune and inflammatory diseases, such as rheumatoid arthritis, Crohn's disease, chronic heart failure and septic shock. Inhibiting the bio-activity of hTNF-alpha is one of the strategy for the treatment of these diseases. Compared with traditional recombinant protein drugs, small molecule drugs have many advantages, such as high affinity, low immunogenecity and low cost. Systematic evolution of ligands by exponential enrichment (SELEX) is a powerful method for the selection of oligonucleotides that bind with high affinity and specificity to target proteins. Such oligonucleotides are called aptamers, and are potential therapeutics for blocking the activity of pathologically relevant proteins. To obtain oligonucleotide aptamers specifically binding to TNF, a 40nt random DNA combinatorial library flanked by 31nt fixed sequences was chemically synthesized. The random library was amplified with PCR and subjected to selection by SELEX protocol against hTNFalpha. After incubation of the library with hTNFalpha, the mixture was blotted onto Immobilon-NC transfer membrane. The no-specific binding was washed away and the hTNFa binding aptamers were eluted and detached from the target protein. The eluted oligo nucleotides were amplified with PCR and served as the DNA library for the next round selection. After 12 rounds of such selection, the selected aptamers were cloned to pGEM-T vector. Positive clones were identified by restriction enzyme digestion and DNA sequencing. Oligo DNA were synthesized according to the sequence data and tested for their activities. Binding activity of the aptamers to hTNFalpha were detected by ELISA and dot blot with biotin-streptavidin-horseradish peroxidase system. Mouse L929 cells were used to test the anti-hTNFa activity of the DNA aptamers. The aptamers were incubated with hTNFalpha and added to the L929 cells. The results were read under microscope and with MTT staining. It was shown that these DNA aptamers bound to hTNFalpha with high affinity, and can inhibit the cytotoxicity of hTNFalpha on cell culture. The affinity of these aptamers are different and may related to their structure. These ssDNA aptamers are potential for the treatment and diagnosis of hTNFalpha related diseases. |
| 2005 | Postoperative Delirium after elective and emergency surgery: analysis and checking of risk factors. A study protocol. | BMC Surg | Delirum is common in hospitalized elderly patients and may be associated with increased morbidity, length of stay and patient care costs. Delirium (acute confusional state) is defined as an acute disorder of attention and cognition. In elderly patients, delirium is often an early indicator of patho-physiological disturbances. Despite landmark studies dating back to the 1940s, the pathogenesis of Delirium remains poorly understood. Early investigators noted that Delirium was characterized by global cortical dysfunction that was associated predominantly with specific electroencephalographic changes. It's important to understand the risk factors and incidence of Delirium. Some of the risk factors are already identified in literature and can be summarized in the word "VINDICATE" which stands for: Vascular, Infections, Nutrition, Drugs, Injury, Cardiac, Autoimmune, Tumors, Endocrine. Aims of this study are: to re-evaluate the above mentioned clinical risk factors, adding some others selected from literature, and to test, as risk factors, a pattern of some genes associated to cognitive dysfunction and inflammation possibly related to postoperative Delirium.All patients admitted to our Emergency Unit who are meet our inclusion/exclusion criteria will be recruited. The arising of postoperative Delirium will select incidentally two groups (Delirium/non Delirium) and the forward analysis of correlate risk factors will be performed. As in a typical observational case/control study we will consider all the exposure factors to which our population are submitted towards the outcome (presence of Delirium). Our exposures are the following: ASA, Pain (SVS; VAS), Blood gas analysis (pH; Hb; pO2; pCO2), Residence pharmacological therapy (BDZ; hypnotics; narcotic drugs; alcohol; nitrous derivates), Body temperature, Arterial pressure, Heart frequency, Breath frequency, Na, K, Creatinin, Glicemia, Albumin, Hct, White blood cells, Glasgow Coma Scale (GCS), Cognitive state (SPMSQ), Functional state (ADL and IADL), Psychological Distress (HADS), Cumulative Illness Rating Scale (CIRS), Hypotension (classified in: light; moderate and severe and duration), Blood loss (classified in: < 2 lt and > 2 lt), Blood transfusions (< 2 lt and > 2 lt), Quantity of red cells and plasma transfusions, Visual VAS / SVS (timing: I-II-III post-operative day), Red cells and Plasma transfusions, Blood count evaluation and Saturation (O2%), Postoperative analgesia (Emilia-Romagna protocol), Presence of malignant tumoral disease, APACHE Score II. Moreover the presence of some relevant genetic polymorphisms will be studied in different genes such as IL-6, IL-10, TNF-alpha, and IL-1 cluster. |
| 2005 | Effects of naltrexone on lipopolysaccharide-induced sepsis in rats. | J Biomed Sci | Naltrexone, an opioid antagonist, has been reported to possess an anti-inflammatory effect via blockade of opioid receptor. The aim of this study is to evaluate the protective effect of naltrexone on LPS-induced septic shock in rats. Sepsis was induced by administration of LPS (10 mg/kg, i.v.) in anesthetized rats. Results demonstrated that pretreatment with naltrexone (10 mg/kg, i.v.) significantly ameliorated hypotension and bradycardia of rats 6 h after LPS administration. In isolated blood vessel, study showed that pretreatment with naltrexone significantly improved norepinephrine-induced vasoconstriction and ACh-induced vasorelaxation in aorta of endotoxemic animals. Naltrexone significantly reduced the elevation of serum glutamate-oxalacetate transaminase and glutamate-pyruvate transaminase (as index of hepatic function) induced by LPS. The infiltration of polymorphonuclear neutrophils into liver 48 h after LPS treatment in mice was also reduced by naltrexone. On the other hand, naltrexone significantly decreased the levels of plasma TNF-alpha and inhibited overproduction of superoxide anions in aortic rings. However, naltrexone did not suppress the overproduction of NO (measured by its metabolites nitrite/nitrate in plasma) and iNOS expression in lungs induced by LPS. In in vitro study, naltrexone did not attenuate non-enzymatic iron-induced lipid peroxidation in rat brain homogenates. In conclusion, pretreatment with naltrexone significantly improved circulatory failure and hepatic dysfunction in sepsis. These effects were associated with reduction of TNF-alpha levels and superoxide anion formation, which may be attributed to antagonism of opioid receptors. |
| 2005 | Strain-specific effects of probiotics on gut barrier integrity following hemorrhagic shock. | Infect Immun | Probiotic therapy modulates the composition of the intestinal flora and inhibits the inflammatory response. These properties may be of benefit in the preservation of gut barrier integrity after injury or stress. In this study, we examined the effect of two Lactobacillus strains selected for their pathogen exclusion properties on intestinal barrier integrity following hemorrhagic shock. Additionally, the responsiveness of the macrophage cell line RAW 264.7 to combined exposure to Lactobacillus DNA or oligodeoxynucleotides containing CpG motifs (CpG-ODN) and endotoxin was assessed by measuring tumor necrosis factor alpha (TNF-alpha) release. Rats were administered lactobacilli (5 x 10(9) CFU) or vehicle for 7 days and were subjected subsequently to hemorrhagic shock by withdrawal of 2.1 ml blood/100 g tissue. Levels of plasma endotoxin, bacterial translocation to distant organs, and filamentous actin (F-actin) in the ileum were determined 24 h later. Rats treated with Lactobacillus rhamnosus showed reduced levels of plasma endotoxin (8 +/- 2 pg/ml versus 24 +/- 4 pg/ml; P = 0.01), bacterial translocation (2 CFU/gram versus 369 CFU/gram; P < 0.01), and disruption of F-actin distribution following hemorrhagic shock compared with nontreated control rats. In contrast, pretreatment with Lactobacillus fermentum had no substantial effect on gut barrier integrity. Interestingly, DNA preparations from both lactobacilli reduced endotoxin-induced TNF-alpha release dose dependently, whereas CpG-ODN increased TNF-alpha release. In conclusion, the pathogen exclusion properties of both Lactobacillus strains and the reduction of endotoxin-induced inflammation by their DNA in vitro are not prerequisites for a beneficial effect of probiotic therapy on gut barrier function following hemorrhagic shock. Although pretreatment with Lactobacillus spp. may be useful to preserve gut barrier integrity following severe hypotension, a thorough assessment of specific strains seems to be essential. |
| 2005 | Tumor necrosis factor-alpha-induced caspase activation mediates endotoxin-related cardiac dysfunction. | Crit Care Med | Sepsis-induced cardiac dysfunction is a serious clinical syndrome characterized by hypotension, decreased systemic vascular resistance, and elevated cardiac index. Although cytokines such as tumor necrosis factor (TNF)-alpha have been shown to play a significant role early in this response, the downstream effects of TNF-alpha signaling on cardiac function, specifically its relationship to apoptosis, have not been fully elucidated.Previous studies from our laboratory have identified endotoxin-induced apoptosis in cardiac cells in vitro. To further determine the role of lipopolysaccharide-induced apoptosis in vivo, mice were injected intraperitoneally with lipopolysaccharide (4 mg/kg), and cardiac apoptosis was detected and inhibited using a broad-spectrum caspase inhibitor.University research laboratory.Adult male wild-type (B6:129PF1/J) and TNF receptor 1/receptor 2 (TNFR-1/2) knockout mice (B6;129S-Tnfrsf1aTnfrsf1b).We sought to determine the dependence of cardiac apoptosis on TNF-alpha signaling and determine the physiologic role of caspase activation on lipopolysaccharide-induced cardiac dysfunction.Cardiac apoptosis was determined at baseline and at 2, 4, 8, and 24 hrs by detection of capase-3 and -8 activity, cytoplasmic levels of Bax/Bcl-2, cleaved caspase-3 immunohistochemistry, and terminal deoxynucleotidyl transferase UTP nick-end labeling (TUNEL) staining of histologic sections in wild-type and TNFR-1/2 knockout mice. To determine the role of caspase activation in lipopolysaccharide-induced cardiac dysfunction, a broad-spectrum caspase inhibitor Z-Val-Ala-Asp (ome)-FMK (sad) was given, and cardiac function was determined in isolated beating hearts (Langendorff preparation). Our experiments determined that caspase-3-dependent apoptosis was active in cardiac tissue by 2 hrs and that this activation was completely mediated by TNFR-1/2. The Bax/Bcl-2 ratios supported the finding and time course of apoptosis, whereas TUNEL staining of cardiac tissue sections identified sporadic apoptotic ventricular cells. The administration of zVAD significantly inhibited myocardial caspase-3 activity and preserved cardiac physiologic function (Langendorff preparation).Endotoxin induces a TNF-alpha-dependent apoptotic cascade in the myocardium, which contributes to the development of cardiac dysfunction. |
| 2005 | San-Huang-Xie-Xin-Tang attenuates inflammatory responses in lipopolysaccharide-exposed rat lungs. | J Ethnopharmacol | In this study, the potential anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on LPS-induced lung injury were investigated and compared to the profile of dexamethasone (DEXA) in a pre-clinical animal model. Post-treatment with SHXT (75 mg/kg), baicalin (1.5 mg/kg) and DEXA (0.5 mg/kg), significantly inhibited LPS-induced hypotension, lung edema and acute survival rates. Western blotting analysis results indicated that all of them significantly inhibited LPS-induced iNOS, TGF-beta, p38MAPK, and ICAM-1 expressions in the lung tissues. Results from ELISA analysis showed that SHXT, baicalin and DEXA all decreased plasma levels of IL-1beta, TNF-alpha, and MCP-1 caused by LPS. Based on these findings, SHXT and baicalin decreased plasma concentrations of IL-1beta, TNF-alpha, MCP-1, and expressions of TGF-beta, ICAM-1, phosphorylated p38 MAPK, and iNOS, which were associated with lung injury and lethality. These evidences indicated that SHXT and baicalin showed strong anti-inflammatory activity, similar to that observed for DEXA, and therefore implicated that herbal SHXT might be therapeutically useful for the treatment of endotoxic lung injury. |
| 2004 | Vascular dementia. Advances in nosology, diagnosis, treatment and prevention. | Panminerva Med | Ischemic or hemorrhagic cerebrovascular disease (CVD) produces injury of brain regions important for executive function, behavior, and memory leading to decline in cognitive functions and vascular dementia (VaD). Cardiovascular disease may cause VaD from hypoperfusion of susceptible brain areas. CVD may worsen degenerative dementias such as Alzheimer disease (AD). Currently, the global diagnostic category for cognitive impairment of vascular origin is vascular cognitive disorder (VCD). VCD ranges from vascular cognitive impairment (VCI) to VaD. The term VCI is limited to cases of cognitive impairment of vascular etiology, without dementia; VCI is equivalent to vascular mild cognitive impairment (MCI). Risk factors for VaD include age, hypertension, diabetes, smoking, cardiovascular disease (coronary heart disease, congestive heart failure, peripheral vascular disease), atrial fibrillation, left ventricular hypertrophy, hyperhomocysteinemia, orthostatic hypotension, cardiac arrhythmias, hyperfibrinogenemia, sleep apnea, infection, and high C-reactive protein. Research on biomarkers revealed increased CSF-NFL levels in VaD, whereas CSF-tau was normal. CSF-TNF-alpha, VEGF, and TGF-beta were increased in both AD and VaD. VaD shows low CSF acetylcholinesterase levels. This condition responds to acetylcholinesterase inhibitors, confirming the central role of cholinergic deficit in its pathogenesis. Evidence strongly suggests that control of vascular risk factors, in particular hypertension, could prevent VaD. |
| 2005 | Progressive exercise preconditioning protects against circulatory shock during experimental heatstroke. | Shock | Heat shock protein (HSP) 72 expression protects against arterial hypotension in rat heatstroke. HSP72 can also be induced in multiple organs, including hearts from rats with endurance exercise. We validated the hypothesis that progressive exercise preconditioning may confer cardiovascular protection during heatstroke by inducing the overexpression of HSP72 in multiple organs. To deal with the matter, we assessed the effects of heatstroke on mean arterial pressure, heart rate, cardiac output, stroke volume, total peripheral vascular resistance, colonic temperature, blood gases, and serum or tissue levels of tumor necrosis factor-alpha (TNF-alpha) in urethane-anesthetized rats pretreated without or with progressive exercise training for 1, 2, or 3 weeks. In addition, HSP72 expression in multiple organs was determined in different groups of animals. Heatstroke was induced by exposing the rats to a high blanket temperature (43 degrees C); the moment at which mean arterial pressure decreased from the peak value was taken as the time of heatstroke onset. Previous exercise training for 3 weeks, but not 1 or 2 weeks, conferred significant protection against hyperthermia, arterial hypotension, decreased cardiac output, decreased stroke volume, decreased peripheral vascular resistance, and increased levels of serum or tissue TNF-alpha during heatstroke and correlated with overexpression of HSP72 in multiple organs, including heart, liver, and adrenal gland. However, 10 days after 3 weeks of progressive exercise training, when HSP72 expression in multiple organs returned to basal values, the beneficial effects exerted by 3 weeks of exercise training were no longer observed. These results strongly suggest that HSP72 preconditioning with progressive exercise training protects against hyperthermia, circulatory shock, and TNF-alpha overproduction during heatstroke. |
| 2005 | Inducible nitric oxide synthase inhibition potentiates multiple organ dysfunction induced by endotoxin in conscious rats. | J Cardiovasc Pharmacol | This study was designed to investigate the effects of inducible nitric oxide synthase (iNOS) inhibition with S-methylisothiourea (SMT) and L-N-(1-iminoethyl)-lysine (L-Nil) on the endotoxemia induced by intravenous lipopolysaccharide (LPS, 10 mg/kg) in conscious rats. Arterial pressure (AP), heart rate (HR), WBC, platelets, plasma nitrite/nitrate, tumor necrosis factor alpha (TNF alpha), and biochemical factors were measured for 24 hours after LPS with or without iNOS inhibitors. RT-PCR was employed to determine the iNOS and endothelial NOS (eNOS) mRNA. Pathologic examinations of the liver and heart were performed. SMT and L-Nil improved the systemic hypotension and increased the HR after LPS. These agents attenuated the LPS-induced leukocytopenia and thrombocytopenia and the increase in nitrite/nitrate. However, iNOS inhibition aggravated the LPS-induced changes in TNF alpha, all biochemical factors, and the hepatic and cardiac tissue damage. The iNOS mRNA, but not the eNOS, was reduced. Our results in conscious rats indicate that iNOS inhibition enhances the organ dysfunction and tissue damage in sepsis. The discrepancy may be attributed to the method for evaluating the sepsis and the effects of anesthesia. Further investigation is required to ensure the effects of iNOS inhibition on sepsis before iNOS inhibitors can be applied in clinical cases with sepsis. |
| 2005 | Histamine improves survival and protects against interleukin-2-induced pulmonary vascular leak syndrome in mice. | Vascul Pharmacol | The therapeutic efficacy in the treatment of metastatic cancer with high doses of interleukin-2 (IL-2) has been limited by the onset of vascular leak syndrome (VLS) and related toxicities. VLS is characterized by an increase in vascular permeability and severe hypotension resulting in interstitial edema and organ failure. This study explores the protective effects of histamine dihydrochloride (HDC) against IL-2-induced toxicities in mice. Treatment with HDC administered before or after IL-2 (1.25 x 10(6) IU, BID) was shown to protect mice from VLS-related toxicities and mortality in a dose-dependent manner. Survival rates when HDC was added were 56, 75 and 81% at doses of 0.47, 4.7 and 47.0 mg/kg, respectively, compared to 42% survival with IL-2 alone. HDC protected against IL-2-induced macroscopic pulmonary lesions, reduced edema (up to 62% reduction in lung wet/dry weight ratio) and reduced capillary leakage into the lungs as measured by a reduction in Evans Blue dye content. In addition, the systemic effect on serum cytokine levels showed that HDC only moderately lowered IL-2 induced IFN-gamma, IL-6, IL-10, IL-18 and TNF-alpha. Serum levels of IL-1beta, IL-4 and IL-12 were not measurably induced by IL-2 treatment. HDC modulates many cellular functions including regulating cytokines and blocking immune-suppression caused by reactive oxygen species (ROS) generated by the NADPH oxidase. However, the protective effect of HDC on alleviating IL-2-induced pulmonary edema was not related to ROS inhibition. Our data indicate that HDC treatment improves survival and protects against IL-2 induced VLS independent of ROS regulation in mice. |
| 2005 | Role of sensory neuron in reduction of endotoxin-induced hypotension in rats. | Crit Care Med | We attempted to determine whether activation of the sensory neuron contributes to reduction of endotoxin-induced hypotension by inhibiting tumor necrosis factor (TNF)-alpha production via calcitonin gene-related peptide (CGRP) release in rats.Prospective, randomized, controlled study.Research laboratory at a university medical center.Wistar rats weighing 220-280 g.Mean arterial blood pressure was measured in rats administered endotoxin intravenously. Animals were pretreated with capsazepine (a vanilloid receptor antagonist), CGRP(8-37) (a CGRP receptor antagonist), and indomethacin before endotoxin administration. Levels of CGRP, 6-keto-prostaglandin F1alpha, TNF-alpha, and cytokine-induced neutrophil chemoattractant (CINC) were measured by enzyme immunoassay methods. The concentration of NO2/NO3 was measured using the Griess reagent. Tissue levels of messenger RNA of the inducible form of nitric oxide synthase (iNOS) and TNF-alpha were determined by reverse transcription polymerase chain reaction.Both lung levels of CGRP and plasma levels of 6-keto-prostaglandin F1alpha were increased after intravenous administration of endotoxin (5 mg/kg), peaking at 90 mins after endotoxin administration. Increases in plasma levels of 6-keto-prostaglandin F1alpha at 90 mins after endotoxin administration (766 +/- 134 pg/mL) were inhibited by pretreatment with capsazepine (373 +/- 44 pg/mL, p < .05), CGRP(8-37) (406 +/- 64 pg/mL, p < .05), and indomethacin (154 +/- 40 pg/mL, p < .05). Although none of the pretreatments affected a series of endotoxin-induced responses, including increases in lung tissue levels of TNF-alpha, CINC, and iNOS and the resultant hypotension in animals given 5 mg/kg endotoxin, such pretreatments enhanced these pathologic responses in animals given a smaller dose of endotoxin (1 mg/kg) to the same extent as those induced by 5 mg/kg of endotoxin, suggesting that shock responses induced by 5 mg/kg endotoxin are maximum responses and activation of sensory neurons in endotoxin-treated rats is essentially a reparative response.Activation of sensory neurons might contribute to reduction of endotoxin-induced hypotension by releasing CGRP, which is capable of promoting endothelial production of prostacyclin. |
| 2005 | [Differential modulation of TLR2 and TLR4-induced TNF production by murin haemorrhagic shock]. | Ann Fr Anesth Reanim | To investigate the influence of haemorrhagic shock in mice on ex vivo TNF production by whole blood cells (WBC) stimulated through Toll-like receptors (TLR) 4 and 2. STUDY DESIGN AND ANIMALS: Experimental study using BALB/c male mice.Haemorrhage (0,026+/-0,003 ml/g) by transparietal cardiac puncture under general anaesthesia. Measurement of left intraventricular pressure through a direct subcostal cardiac puncture. Possible restitution of shed blood volume (SBV) in retroorbital venous plexus, 60 minutes following haemorrhage. Lethal exsanguination 120 minutes following general anaesthesia (Control group), cardiac puncture (Sham group), blood sample (Haemorrhage group), or 60 minutes following SBV retransfusion (SBV group). Cultures (24 hours) of whole blood from the exsanguination, alone or with Escherichia coli endotoxin (LPS, TLR 4) or with heat-killed Staphylococcus aureus Cowan (SAC, TLR 2). Assessment of TNF levels in the cultures supernatant (Elisa).Hemorrhage (approximately 30% of calculated blood volume) resulted in arterial hypotension (-50%) which was reversed by SBV retransfusion. TNF production by LPS-stimulated WBC was reduced by haemorrhage (approximately -50%) with or without SBV retransfusion. TNF production by SAC-stimulated WBC remained unchanged.The reduction of proinflammatory cytokines production by WBC stimulated with pathogen-associated molecular patterns is not a generalized phenomenon following murin haemorrhagic shock. It depends on the used stimulus and studied signalling pathways. |
| Effects of post-treatment with low-dose propofol on inflammatory responses to lipopolysaccharide-induced shock in conscious rats. | Clin Exp Pharmacol Physiol | 1. In the present study, we used a low dose of propofol (5 mg/kg per h) to investigate its effects on the pro-inflammatory cytokines (tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-10) and changes in nitric oxide (NO) following lipopolysaccharide (LPS) for a period of 12 h in conscious rats. 2. Experiments were designed to induce endotoxin shock by intravenous injection of Klebsiella pneumoniae LPS (10 mg/kg) in conscious rats. Arterial pressure (AP) and heart rate (HR) were monitored continuously for 12 h after LPS administration. Tumour necrosis factor-alpha, IL-1beta, IL-10 and plasma nitrates/nitrites were determined before and 0.5, 1, 3, 6, 9 and 12 h after LPS administration. A low dose of intravenous propofol (5 mg/kg per h) was administered to investigate the effects on cytokine responses and changes in NO in endotoxin shock. 3. Lipopolysaccharide significantly increased TNF-alpha, IL-1beta, IL-10, nitrites/nitrates and HR, whereas mean AP was decreased. Post-treatment with propofol suppressed the release of TNF-alpha, IL-1beta, IL-10 and NO production after endotoxin shock. 4. Lipopolysaccharide also caused a decrease in the white blood cell count and haematocrit. 5. Post-treatment with propofol slightly, but not significantly, affected the LPS-induced systemic hypotension, tachycardia, leukocytopenia and anaemia. 6. These findings suggest that low-dose propofol may be beneficial to the inflammatory change in sepsis. |
| 2005 | Dose effects of propofol on hemodynamic and cytokine responses to endotoxemia in rats. | J Anesth | Our previous studies have demonstrated that propofol inhibits hypotension, metabolic acidosis, and cytokine responses and reduces mortality in endotoxemic rats. The purpose of this study was to elucidate whether these beneficial effects of propofol on hemodynamics and cytokine responses were dose related.Forty-eight rats were divided at random among four equal groups: groups S, M, and L received intravenous propofol administration (5, 10, and 20 mg.kg(-1).h(-1), respectively) immediately after endotoxin (Escherichia coli endotoxin; 15 mg.kg(-1), i.v.) was given. Group E received endotoxin alone. We assessed hemodynamics and plasma cytokine [tumor necrosis factor (TNF)-alpha and interleukin (IL)-6] concentrations for 5 h following endotoxin injection.Systolic arterial pressure (SAP) was significantly higher at 4 and 5 h in groups S and M than in group E (P < 0.05), although SAP decreased progressively in all groups. Endotoxin injection increased the TNF-alpha and IL-6 concentrations in all groups. The increase in TNF-alpha concentrations at 2 h was significantly lower in group M than in group E (P < 0.05). On the other hand, the increase in IL-6 concentration at 5 h was significantly lower in groups M and L than in group E (P < 0.05).The effects of propofol on blood pressure and cytokine responses were influenced by the dose of propofol, although the relationship did not follow simple linearity. |
| 2005 | Thaliporphine increases survival rate and attenuates multiple organ injury in LPS-induced endotoxaemia. | Naunyn Schmiedebergs Arch Pharmacol | This study addressed the question of whether thaliporphine, a phenolic aporphine alkaloid obtained from Chinese herbs and possessing antioxidant and alpha-1 adrenoceptor antagonistic activity, has protective effects in endotoxaemic rats and we attempted to elucidate the mechanisms contributing to such protective effects. Injection of rats with endotoxin (E. coli lipopolysaccharide, LPS) induced severe hypotension and tachycardia as well as vascular hyporeactivity to noradrenaline. Pretreatment of LPS-treated rats with thaliporphine attenuated the delayed hypotension significantly whilst only a higher dose (1 mg/kg) of thaliporphine decreased LPS-induced tachycardia. LPS significantly increased nitric oxide (NO.) and superoxide anion (O(2).(-)) levels, a response that was reduced by pretreatment with 1 mg/kg thaliporphine. Endotoxaemia for 240 min resulted in a bell-shaped time course for the change of serum tumour necrosis factor-alpha (TNF-alpha) level with a peak at 60 min. Pretreatment of LPS-treated rats with 1 mg/kg thaliporphine significantly reduced the serum TNF-alpha level at 60 min. In addition, LPS caused a biphasic change in blood glucose and thaliporphine attenuated the late-phase decrease in blood glucose. Endotoxaemia induced multiple organ injury in the liver, kidney and heart, as indicated by increases of aspartate aminotransferase (GOT), alanine aminotransferase (GPT), creatinine (CRE), lactate dehydrogenase (LDH) and creatine phosphate kinase muscle-brain (CKMB) levels in serum. These increases of biochemical markers and inflammatory cell infiltration into injured tissues were reduced significantly by treatment with thaliporphine. In addition, thaliporphine increased the survival rate of LPS-treated mice dose-dependently. In conclusion, our results suggest that thaliporphine could be a novel agent for attenuating endotoxin-induced circulatory failure and multiple organ injury and may increase the survival rate. These beneficial effects of thaliporphine may be attributed to the suppression of TNF-alpha, NO. and O(2).(-) production. |
| 2005 | Acute inflammatory response to endotoxin in mice and humans. | Clin Diagn Lab Immunol | Endotoxin injection has been widely used to study the acute inflammatory response. In this study, we directly compared the inflammatory responses to endotoxin in mice and humans. Escherichia coli type O113 endotoxin was prepared under identical conditions, verified to be of equal biological potency, and used for both mice and humans. The dose of endotoxin needed to induce an interleukin-6 (IL-6) concentration in plasma of approximately 1,000 pg/ml 2 h after injection was 2 ng/kg of body weight in humans and 500 ng/kg in mice. Healthy adult volunteers were injected intravenously with endotoxin, and male C57BL/6 mice (n=4 to 12) were injected intraperitoneally with endotoxin. Physiological, hematological, and cytokine responses were determined. Endotoxin induced a rapid physiological response in humans (fever, tachycardia, and slight hypotension) but not in mice. Both mice and humans exhibited lymphopenia with a nadir at 4 h and recovery by 24 h. The levels of tumor necrosis factor (TNF) and IL-6 in plasma peaked at 2 h and returned to baseline levels by 4 to 6 h. IL-1 receptor antagonist RA and TNF soluble receptor I were upregulated in both mice and humans but were upregulated more strongly in humans. Mice produced greater levels of CXC chemokines, and both mice and humans exhibited peak production at 2 h. These studies demonstrate that although differences exist and a higher endotoxin challenge is necessary in mice, there are several similarities in the inflammatory response to endotoxin in mice and humans. |
| 2005 | Antioxidant eugenosedin-A protects against lipopolysaccharide-induced hypotension, hyperglycaemia and cytokine immunoreactivity in rats and mice. | J Pharm Pharmacol | Eugenosedin-A has been demonstrated to possess alpha/beta-adrenoceptor and serotonergic receptor blocking activities. We have investigated by what mechanisms eugenosedin-A prevents lipopolysaccharide (LPS)-induced hypotension, vascular hyporeactivity, hyperglycaemia, oxidative injury or inflammatory cytokines formation in rats. Intravenous administration of eugenosedin-A, trazodone, yohimbine (1 mg kg(-1)), aminoguanidine or ascorbic acid (15 mg kg(-1)) normalized LPS (10 mg kg(-1))-induced hypotension. Pretreatment with eugenosedin-A or the other agents 30 min before LPS injection reduced aortic hyporeactivity. LPS-induced increases in plasma interleukin-1beta (IL-beta), IL-6, interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and blood glucose levels were significantly inhibited by eugenosedin-A (1 mg kg(-1), i. v.). The same dose of trazodone, a chloropiperazinylbenzene-type antidepressant, and yohimbine, an alpha(2)-adrenoceptor antagonist, reduced IL-1beta and TNF-alpha, but it could not inhibit hyperglycaemia. Aminoguanidine, an inducible nitric oxide synthase (iNOS) inhibitor, and ascorbic acid, an antioxidant, decreased IL-1beta, TNF-alpha contents and hyperglycaemia. Eugenosedin-A and the other agents inhibited Fe(2+)-ascorbic acid-induced peroxidation in rat cortex, indicating that those agents had antioxidant effects, with the exception of aminoguanidine. In free radical scavenged experiments, eugenosedin-A and ascorbic acid eliminated peroxyl radicals. All test agents inhibited the LPS-induced increase of malondialdehyde (MDA) content in rat brain homogenates. When mice were administered an intraperitoneal injection of LPS alone, mortality occurred from 4 to 16 h, after which time all were dead. However, eugenosedin-A significantly prolonged the survival time after LPS injection, suggesting that eugenosedin-A protected against LPS-induced cardiovascular dysfunction, hyperglycaemia, tissue injury and inflammatory cytokine production. This was attributable mainly to the antioxidant and peroxyl radical scavenged effects of eugenosedin-A, and which may be, at least in part, due to its blockade on alpha/beta-adrenergic and serotonergic receptors. |
| 2005 | [Protective effect of the cholinergic anti-inflammatory pathway against hemorrhagic shock in rats]. | Zhongguo Wei Zhong Bing Ji Jiu Yi Xue | To investigate the effect of the cholinergic anti-inflammatory pathway on hemodynamics in hemorrhaged rats.Hemorrhagic shock was induced by modified Wiggers method until mean arterial pressure (MAP) was stabilized within the range of 35 to 40 mm Hg (1 mmHg=0.133 kPa). Thirty male Sprague-Dawley rats were randomly divided into six groups: sham group, hemorrhagic shock (Hem) group, vagotomy (VGX) group, vagus stimulation (STM) group, cholinergic inhibitor (THA) group and N receptor inhibitor (alpha-BGT) group. The distal end of the left vagus nerve trunk was placed on bipolar platinum electrode connected to a stimulation module and controlled by an acquisition system. Stimuli with constant voltage (5 V, 2 ms, 1 Hz) were applied to nerve for 12 minutes, starting 5 minutes after MAP stabilized at a level of 35 to 40 mmHg. Before stimulation a blood pressure transducer was implanted in the common carotid artery for continuous registration of MAP. Blood samples and liver samples were collected from animals of all groups after stimulation. Serum levels of tumor necrosis factor-alpha (TNF-alpha) and liver nuclear factor kappa-B (NF-KappaB) were determined.MAP was markedly lowered at the end of bleeding, and the levels of serum TNF-alpha and liver NF-KappaB markedly increased 45 minutes after the bleeding was discontinued. Bilateral cervical vagotomy did not significantly modify the changes in serum TNF-alpha, but slightly increased liver NF-KappaB activation. Application of constant electric current to the distal end of the vagus trunk significantly reduced serum TNF-alpha and blunted liver NF-KappaB activation. Tetrahydroamino-acridine (THA,1.5 mg/kg, intravenous drip administration after bilateral cervical vagotomy reversed hypotension and attenuated serum TNF-alpha and liver NF-KappaB amounts, but alpha-bungarotoxin (1.0 microg/kg intravenous drip) pretreatment reverted the inhibitory effects of vagal stimulation.The result suggest that direct electrical stimulation of the vagus nerve and its transmitter can significantly attenuate peak serum TNF-alpha amounts, inhibit the expression of liver NF-KappaB, and prevent the development of hypotension, thus it might produce a potential protective effect on hemorrhaged rats through acetylcholine (Ach) binds NAch receptor alpha 7 subunit which exists in the macrophage. |
| 2004 | Effect of methylguanidine in a model of septic shock induced by LPS. | Free Radic Res | Septic shock, a severe form of sepsis, is characterized by cardiovascular collapse following microbial invasion of the body. The progressive hypotension, hyporeactivity to vasopressor agents and vascular leak leads to circulatory failure with multiple organ dysfunction and death. Many inflammatory mediators (e.g. TNF-alpha, IL-1 and IL-6) are involved in the pathogenesis of shock and, among them, nitric oxide (NO). The overproduction of NO during septic shock has been demonstrated to contribute to circulatory failure, myocardial dysfunction, organ injury and multiple organ failure. We have previously demonstrated with in vitro and in vivo studies that methylguanidine (MG), a guanidine compound deriving from protein catabolism, significantly inhibits iNOS activity, TNF-alpha release and carrageenan-induced acute inflammation in rats. The aim of the present study was to evaluate the possible anti-inflammatory activity of MG in a model of septic shock induced by lipopolysaccharide (LPS) in mice. MG was administered intraperitoneally (i.p.) at the dose of 30 mg/kg 1 h before and at 1 and 6 h after LPS-induced shock. LPS injection (10 mg/kg in 0.9% NaCl; 0.1 ml/mouse; i.p.) in mouse developed a shock syndrome with enhanced NO release and liver, kidney and pancreatic damage 18 h later. NOx levels, evaluated as nitrite/nitrate serum levels, was significantly reduced in MG-treated rats (78.6%, p < 0.0001; n = 10). Immunohistochemistry revealed, in the lung tissue of LPS-treated group, a positive staining for nitrotyrosine and poly(adenosine diphosphate [ADP] ribose) synthase, both of which were reduced in MG-treated mice. Furthermore, enzymatic evaluation revealed a significant reduction in liver, renal and pancreatic tissue damage and MG treatment also improved significantly the survival rate. This study provides evidence that MG attenuates the degree of inflammation and tissue damage associated with endotoxic shock in mice. The mechanisms of the anti-inflammatory effect of MG is, at least in part, dependent on the inhibition of NO formation. |
| 2004 | Nitric-oxide-lowering effect of terlipressin in decompensated cirrhosis: comparison to the molecular adsorbent recirculating system and correlation with clinical status. | Eur J Gastroenterol Hepatol | Systemic vasodilatation and arterial hypotension, refractory to adrenergic vasopressors, portend a poor prognosis in patients with decompensated cirrhosis. The production of large amounts of nitric oxide, consequent to endotoxin-induced tumour necrosis factor (TNF)-alpha-mediated upregulation of inducible nitric oxide synthase (iNOS), has been suggested to be central to this phenomenon. Terlipressin has recently been shown in an animal model of cirrhosis to suppress endotoxin-induced TNF-alpha-mediated upregulation of iNOS, thereby preventing overproduction of nitric oxide and restoring normal vascular tone. We present the first evidence that this effect of terlipressin may also occur clinically, in a patient with Child-Pugh class C cirrhosis, endotoxaemia, a raised circulating TNF-alpha concentration, and marked systemic vasodilatation with refractory arterial hypotension. Beneficial effects of terlipressin on circulating nitrate and nitrite concentrations, haemodynamic status, plasma renin levels and indocyanine green clearance were comparable to those of the molecular adsorbent recirculating system (MARS). Our findings suggest that terlipressin may be the vasopressor agent of choice in patients with decompensated cirrhosis and provide a rationale for combination terlipressin and MARS therapy when the therapeutic response to either treatment alone is suboptimal. |
| 2004 | Effects of various antioxidants on endotoxin-induced lung injury and gene expression: mRNA expressions of MnSOD, interleukin-1beta and iNOS. | Chin J Physiol | Antioxidants have been shown to be effective in attenuating acute lung injury. In this study, we determine the effects of various antioxidants by different mechanisms on the lipopolysaccharide (LPS)-induced changes. LPS was administered intravenously at a dose of 10 mg/kg to anesthetized rats. LPS induced a significant decrease in blood pressure (P < 0.01) and increased exhaled nitric oxide (NO) from 3.60+/-0.18 to 35.53+/-3.23 ppb (P < 0.01) during an observation period of 4 h. Plasma nitrate concentrations also increased from 0.61+/-0.06 to 1.54+/-0.22 micromol/l (P < 0.05). LPS-induced oxygen radical release from white blood cells isolated from rat peripheral blood also increased significantly (P < 0.001). After the experiment, the lung weight was obtained and lung tissues were taken for the determination of mRNA expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta) and manganese superoxide dismutase (MnSOD). Histological examination of the lungs was also performed. In the control group injected with saline solution, mRNA expressions of iNOS, IL-1beta, TNF-alpha and MnSOD were absent. Four hours after LPS administration, mRNA expressions of iNOS, IL-1beta, and MnSOD were significantly enhanced, but TNF-alpha was not discernibly expressed. LPS also caused a twofold increase in lung weight. Pathological examination revealed endothelial cell damage and interstitial edema. Various antioxidants were given 1 h after LPS administration. These agents include SOD, catalase (CAT), SOD + CAT or vitamin C (ascorbic acid). These antioxidants effectively reversed the systemic hypotension, reduced the quantity of exhaled NO and plasma nitrate concentration, and prevented acute lung injury. Administration of various antioxidants also significantly attenuated LPS-induced oxygen radical release by rat white blood cells. LPS induced mRNA expressions of MnSOD and iNOS were significantly depressed by these antioxidants. However, only SOD + CAT and vitamin C inhibited the mRNA expression of IL-1beta. These results suggest that oxygen radicals are responsible for LPS-induced lung injury. Antioxidants can attenuate the lung injury by inhibiting mRNA expressions of iNOS and IL-1beta. |
| 2004 | Relationship of asymmetric dimethylarginine to haemodialysis hypotension. | Nitric Oxide | Hypotension is one of the major complications in patients undergoing haemodialysis (HD), that is well evident in patients defined as "hypotension-prone." The mechanisms underlying the hypotensive episodes are not known. We carried out a clinical study on hypotension-prone HD patients to test the existence of a dysregulation in the nitric oxide (NO) generating pathway. Since asymmetric dimethylarginine (ADMA) is an endogenous compound which regulates NO synthesis, we measured its variation in plasma of stable-HD and hypotension-prone patients before, during, and at the end of HD. Before HD, the hypotension-prone patients have higher ADMA levels than stable-HD patients. The HD procedure significantly removes ADMA from plasma of stable-HD patients, while in the hypotension-prone ADMA levels are unchanged at the end of the HD. Moreover, in the hypotension-prone patients, during the hypotensive episode, a dramatic drop of ADMA levels is observed, followed by a rapid increase at the end of the HD. The symmetric dimethylarginine (SDMA), which has no effect on NO synthesis, is also high in plasma of both groups of HD patients compared to normal subjects, and in both groups its levels at the end of HD are significantly reduced. The hypotension-prone patients have basal TNF-alpha levels lower than the stable-HD groups, that significantly increase during the hypotensive episode. On the basis of these findings, we suggest that the hypotensive syndrome could be related to a dysregulation between ADMA metabolism and clearance due both to cytokines release and to an extremely fast ADMA clearance during HD, leading to an increase in NO blood levels. |
| 2005 | Urinary trypsin inhibitor reduces LPS-induced hypotension by suppressing tumor necrosis factor-alpha production through inhibition of Egr-1 expression. | Am J Physiol Heart Circ Physiol | Although urinary trypsin inhibitor (UTI) has been shown to inhibit tumor necrosis factor (TNF)-alpha- production, the detailed mechanism(s) remains unclear. This study was undertaken to elucidate the molecular mechanism(s) underlying this inhibitory effect in monocytes in vitro and in rats given lipopolysaccharide (LPS). TNF-alpha production by monocytes stimulated with LPS (100 ng/ml) was inhibited by UTI at concentrations higher than 100 U/ml. Expression of early growth response factor-1 (Egr-1) and phosphorylation of extracellular signal-regulated protein kinases 1/2 in monocytes stimulated with LPS were inhibited by UTI. UTI (50,000 U/kg i.v.) inhibited LPS (5 mg/kg i.v.)-induced increases in lung tissue levels of Egr-1, TNF-alpha mRNA, and TNF-alpha in rats. UTI inhibited LPS-induced hypotension by inhibiting pulmonary induction of inducible nitric oxide synthase (iNOS). We previously demonstrated that anti-TNF-alpha antibody and aminoguanidine, a selective inhibitor of iNOS, reduced LPS-induced hypotension in this animal model. Furthermore, we also reported that reduction of LPS-induced coagulation abnormalities in rats did not affect inflammatory responses and hypotension in this animal model. Taken together, these observations strongly suggested that UTI inhibited LPS-induced production of TNF-alpha by inhibiting activation of the extracellular signal-regulated protein kinases 1/2-Egr-1 pathway in monocytes, which might at least partly contribute to reduction of hypotension through inhibition of iNOS induction in rats given LPS. |
| 2004 | Urgosedin inhibits hypotension, hypoglycemia, and pro-inflammatory mediators induced by lipopolysaccharide. | J Cardiovasc Pharmacol | Urgosedin is a newly synthesized compound especially with serotonergic and alpha-adrenergic blocking actions. In rat isolated thoracic aorta, urgosedin competitively antagonized norepinephrine-, clonidine-, and serotonin-induced vasocontractions in a concentration-dependent manner. In radioligand binding experiments, urgosedin had significant binding affinities on alpha1/alpha2, 5-HT1A, 5-HT1B and 5-HT2A receptors. Intravenous injection of lipopolysaccharide (LPS) produced a biphasic hypotension in normotensive rats. Although intravenous injection of urgosedin caused minor depressor actions in the normotensive Wistar rat, urgosedin significantly attenuated the secondary prolonged hypotension produced by LPS. The plasma levels of cytokines (IL-1beta, IL-6, TNF-alpha, and IFN-gamma) and hypoglycemia induced by LPS were also reduced by urgosedin. Moreover, the acute survival rates (350 minutes) of endotoxic shock increased from 0% (LPS group) to 100% in the groups pretreated with urgosedin. In RAW264.7 cells, urgosedin inhibited LPS-induced inducible nitric oxide synthase (iNOS) expression. In conclusion, our data suggest that urgosedin was a newly potent serotonergic and mild alpha-adrenergic blocking agent. Its prevention of LPS-induced hypotension and hypoglycemia might partially mediate through its inhibition activities on the iNOS expression and cytokines formation. Urgosedin might be an effective pharmacological agent against LPS-induced hypotension, hypoglycemia, and the formation of pro-inflammatory mediators. |
| 2004 | High-fat enteral nutrition reduces endotoxin, tumor necrosis factor-alpha and gut permeability in bile duct-ligated rats subjected to hemorrhagic shock. | J Hepatol | Cholestatic patients are prone to septic complications after major surgery due to an increased susceptibility to endotoxin and hypotension. High-fat enteral nutrition reduces endotoxin after hemorrhagic shock. However, it is unknown whether this nutritional intervention is protective in biliary obstruction. We investigated the effect of high-fat enteral nutrition on endotoxin, tumor necrosis factor-alpha (TNF-alpha) and intestinal permeability in cholestatic rats subjected to hemorrhagic shock.Bile duct-ligated (BDL) rats were fasted or fed with low-fat or high-fat enteral nutrition before hemorrhagic shock. Blood and tissue samples were taken after 90 min.Plasma endotoxin decreased after hemorrhagic shock in BDL-rats fed with high-fat nutrition compared to fasted (P<0.01) and low-fat treated rats (P<0.05). Additionally, circulating TNF-alpha was reduced in BDL-rats pretreated with high-fat nutrition compared to fasted rats (P<0.01). The increased intestinal permeability to macromolecules was reduced by high-fat enteral nutrition, whereas bacterial translocation did not significantly change. Simultaneously, tight junction distribution in ileum and colon was disrupted in non-treated BDL-rats but remained unchanged in high-fat pretreated BDL-rats.High-fat enteral nutrition protects against endotoxin-mediated complications independently of intraluminal bile. These results provide a potential new strategy to prevent endotoxin-mediated complications in cholestatic patients undergoing major surgery. |
| 2004 | Prevention of endothelial cell injury by activated protein C: the molecular mechanism(s) and therapeutic implications. | Curr Vasc Pharmacol | Activated protein C (APC), a natural anticoagulant, is formed from protein C by the action of thrombin bound to thrombomodulin on the endothelial cell surface. APC regulates the coagulation system by inactivating the activated form of factors V and VIII in the presence of protein S. Tumor necrosis factor-alpha (TNF-alpha) plays critical roles in the development of disseminated intravascular coagulation, acute respiratory distress syndrome and shock in sepsis by inducing endothelial cell damage through activation of neutrophils. APC reduces the pulmonary endothelial cell injury and hypotension in rats administered endotoxin (ET) by inhibiting TNF-alpha production through inhibition of its transcription. Furthermore, APC reduces the ischemia/reperfusion-induced renal injury and the stress-induced gastric mucosal injury in rats. Inhibition by APC of the endothelial cell damage inhibited the decrease in the endothelial production of prostacyclin in vivo. These therapeutic effects could not be attributed to its anticoagulant effects, but to inhibition of TNF-alpha production. APC inhibits ET-induced TNF-alpha production in vitro in human monocytes by inhibiting activation of NFkappaB and AP-1 by inhibiting degradation of IkappaB and mitogen-activated protein kinase pathways, respectively. Recombinant APC was reported to reduce the mortality of patients with severe sepsis. These observations strongly suggest that APC might be involved not only in regulation of the coagulation system, but in regulation of inflammatory responses by preventing endothelial cell injury. Furthermore, APC reduced the spinal cord injury induced by compression-trauma or ischemia/reperfusion by inhibiting TNF-alpha production in rats, suggesting that APC may be a potential therapeutic agent for spinal cord injury in which only limited therapeutic measures are currently available. |
| 2004 | The opioid antagonist naltrexone blocks acute endotoxic shock by inhibiting tumor necrosis factor-alpha production. | Brain Behav Immun | Septic shock is believed to be a consequence of excessive stimulation of the immune system by bacterial toxins that results in systemic overproduction of proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha), IL-1, and IL-6. Various studies have shown that TNF-alpha, a major mediator of septic shock, induces tissue injury, loss of blood pressure, organ failure, and ultimately death. Administration of the opioid antagonist naloxone has been reported to reverse opiate-mediated hypotension, promote organ perfusion and increase patient survival. In this study, we examined the mechanism by which the opioid receptor antagonist, naltrexone, modulates the septic shock response in BALB/c mice after injection with lipopolysaccharide (LPS) or staphylococcal enterotoxin B (SEB) in combination with d-galactosamine (d-gal), or with agonistic anti-Fas antibody (Jo2) alone. Each of these treatments induced rapid-onset, acute shock, and ultimately mortality (6-9h after injection), although different mechanisms are involved. Administration of the opioid antagonist naltrexone protected mice from shock induced by LPS+d-gal, but not SEB+d-gal or Jo2 antibody, a protective effect that was reversed by morphine. Naltrexone significantly inhibited the production of TNF-alpha induced by LPS, but not SEB in vivo. When bone marrow-derived, splenic or peritoneal macrophages were treated with LPS in vitro, administration of naltrexone had no direct effect on TNF-alpha production. These results suggest that naltrexone is capable of preventing LPS-induced septic shock mortality by indirect inhibition of TNF-alpha production in vivo. |
| 2004 | Effects of isoflurane-induced and prostaglandin E(1)-induced hypotension on cytokine responses to oral and maxillofacial surgery. | J Clin Anesth | To evaluate the effect of induced hypotension with isoflurane or prostaglandin E(1) (PGE(1)) on cytokine responses to surgery.Prospective, randomized study.University hospital.24 ASA physical status I and II patients undergoing elective oral and maxillofacial surgery.Patients were randomly allocated to three groups be anesthetized in the normotension (Control group), isoflurane-induced hypotension (Isoflurane-H group), and PGE(1)-induced hypotension (PGE(1)-H group). Mean arterial pressure during hypotension was maintained at approximately 80% of baseline values.Blood samples were taken before induction of anesthesia and during and after hypotension. Plasma tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-10 (IL-10) levels were measured using enzyme-linked immunosorbent assay. There were no differences in TNF-alpha or IL-10 levels among the groups. However, the elevation of the plasma IL-6 level in the PGE(1)-H group was found during hypotension, compared with the control group (p < 0.05).PGE(1)-induced hypotension has an effect on IL-6 response to oral and maxillofacial surgery. |
| 2004 | A prostaglandin E2 receptor subtype EP4 agonist attenuates cardiovascular depression in endotoxin shock by inhibiting inflammatory cytokines and nitric oxide production. | Shock | The prostaglandin (PG) E2 receptor subtype EP4 has been found to mediate regulation of inflammatory cytokines in macrophages and neutrophils in vitro by PGE2. Yet the role of EP4 receptors in endotoxin shock in vivo and whether EP4 activation is a beneficial treatment are not clear. We tested the effect of an EP4 agonist on hemodynamic changes and production of inflammatory cytokines in a rat endotoxin-induced shock model. In rats under pentobarbital anesthesia, lipopolysaccharide (LPS) was injected, and an EP4 agonist (ONO-AE1-329) was administered at one of three concentrations (1, 3, or 10 microg/kg bolus i.v. hourly). Mean arterial pressure (MAP) was monitored throughout the experiment, and pressor responses to norepinephrine were determined 6 h after LPS injection. Serum tumor necrosis factor (TNF)-alpha and serum interleukin (IL)-6 were measured 1 h and 6 h after LPS injection. Venous nitrosyl hemoglobin (NO-Hb) concentration was measured by electron spin resonance. Expression of mRNAs encoding TNF-alpha and inducible nitric oxide synthase (iNOS) in the left ventricle and descending aorta was determined with a real-time reverse transcription polymerase chain reaction. As time progressed, LPS significantly depressed MAP and decreased reactivity to norepinephrine. Infusion of higher doses of the EP4 agonist at 3 and 10 microg/kg/h attenuated LPS-induced hypotension and hyporeactivity to norepinephrine. LPS significantly increased serum concentrations of TNF-alpha and IL-6, and higher doses of EP4 agonist significantly attenuated these increases. Left ventricular and aortic expression of mRNAs encoding TNF-alpha and iNOS was increased by LPS; again, EP4 agonist at higher doses attenuated the increases. LPS-induced production of inflammatory mediators and cardiovascular depression were attenuated by EP4 agonist administration in an in vivo endotoxin shock model. Anti-inflammatory effects thus would be involved in protection by EP4 agonist against cardiovascular depression in endotoxin shock. |
| 2004 | [Protective effect of ketamine against septic shock in rats]. | Zhongguo Wei Zhong Bing Ji Jiu Yi Xue | To investigate the effects and the mechanism of ketamine on hemodynamics and pro-inflammatory cytokine levels of plasma in septic shock rats.Cecal ligation and puncture (CLP) was used to reproduce septic shock model. Twenty healthy and male Sprague-Dawlay (SD) rats weighing (225+/-25) g were randomly divided into four equal groups: Sham CLP group, CLP group, ketamine I (KT I) and ketamine II (KT II) group. Thirty minutes before CLP, normal saline (0.9 %) was infused continuously at a rate of 5 ml.kg(-1).h(-1) through the left femoral vein cannula in sham CLP and CLP group, and ketamine (5 mg.kg(-1).h(-1) and 10 mg.kg(-1).h(-1), respectively) was infused continuously in KT I or KT II group. The right femoral artery was cannulated to monitor mean arterial pressure. The plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured using enzyme-linked immunosorbent assays (ELISA).CLP produced progressive hypotension, and a large increase in the plasma TNF-alpha and IL-6 concentrations. The hemodynamic responses were reversed and the cytokine responses were suppressed in ketamine treated animals.Ketamine administration has protective effect against septic shock in CLP rats. |
| Hemocompatibility of PMEA coated oxygenators used for extracorporeal circulation procedures. | ASAIO J | An inflammatory response to cardiopulmonary bypass (CPB) caused by bioincompatibility of extracorporeal circuits is one of the major clinical issues in cardiac surgery. Recently a new coating material, poly-2-methoxyethylacrylate (PMEA), was developed to improve the biocompatibility of blood contacting surfaces. In a simulated cardiopulmonary bypass model, using fresh human whole blood, 15 membrane oxygenators (Capiox SX18, Terumo Corp., Tokyo, Japan) were compared. Five of them had the PMEA coating, five had a heparin-coated surface, and five had no surface treatment. Blood samples were taken at several time-points during a 90 minute circulation period. Changes in coagulation, complement, and blood cell alteration factors were measured by ELISA methods, plasma bradykinin levels were measured by radioimmunoassay, and expression of genes encoding cytokines TNF-alpha, interleukin-1beta, interleukin-6, and interleukin-8 was determined by semiquantitative real time RT-PCR. Platelet adhesion was significantly reduced in both the PMEA and the heparin coated circuits. Release of platelet activation marker beta-thromboglobulin was significantly higher in the uncoated control group (p < 0.01). After 5 minutes of blood circulation bradykinin levels significantly increased in all three groups (p < 0.01); however, the group with the PMEA coated oxygenators showed the lowest values. Expression of genes encoding proinflammatory cytokines in monocytes was increased in all groups, with the lowest being in the PMEA coated group. PMEA coated CPB surfaces in an in vitro experimental model showed an improved thrombogenicity, reduced bradykinin release, less platelet activation and less proinflammatory cytokines gene expression in comparison with a noncoated group. The authors assume that PMEA coating may ameliorate some of intra- and postperfusion syndromes, particularly hypotension, unspecific inflammation, hyperfibrinolysis, and blood loss. |
| 2004 | Regulation of inflammatory responses by activated protein C: the molecular mechanism(s) and therapeutic implications. | Clin Chem Lab Med | Activated protein C (APC), a natural anticoagulant, is formed from protein C by the action of the thrombin-thrombomodulin (TM) complex on the endothelial cell surface. Endothelial protein C receptor augments the activation of protein C by the thrombin/TM system. APC inactivates the activated form of coagulation factors V and VIII in the presence of protein S. Administration of APC reduced the pulmonary vascular injury and hypotension as well as the coagulation abnormalities by inhibiting production of the tumor necrosis factor-alpha (TNF-alpha) in rats given endotoxin (ET). These therapeutic effects of APC could not be attributed to its anticoagulant effects. APC inhibited ET-induced TNF-alpha production in human monocytes by inhibiting activation of nuclear factor K-B and activator protein-1 in vitro. Administration of the human plasma-derived APC ameliorated coagulation abnormalities without any adverse effects in patients with disseminated intravascular coagulation (DIC). Recombinant APC was reported to reduce the mortality of patients with severe sepsis, and the therapeutic effect was more marked in such patients with overt DIC than those without it. These observations strongly suggest that APC plays important roles in the regulation of inflammation as well as coagulation. Both anti-inflammatory and anticoagulant properties of APC might contribute to the therapeutic usefulness in patients with severe sepsis. |
| 2004 | Effects of hyperchloremic acidosis on arterial pressure and circulating inflammatory molecules in experimental sepsis. | Chest | To determine the effects of hyperchloremic acidosis, induced by dilute HCl infusion, on BP and circulating inflammatory mediators in an experimental model of severe sepsis in the rat.Randomized, open-label, controlled experiment.University research laboratory.Twenty-four adult, male, Sprague-Dawley rats.Eighteen hours after inducing lethal sepsis by cecal ligation and puncture, animals were randomized and classified into three groups. In groups 2 and 3, we began an IV infusion of 0.1 N HCl to reduce the standard base excess (SBE) by 5 to 10 mEq/L and 10 to 15 mEq/L, respectively. In group 1, we infused a similar volume of lactated Ringer solution. In all groups, infusions were continued for 8 h or until the animals died.We measured mean arterial pressure (MAP), arterial blood gases, electrolytes, plasma nitrate/nitrite, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-10 levels at 0 h, 3 h, 6 h, and 8 h.MAP remained stable in group 1 but decreased in groups 2 and 3 (p < 0.001), such that at 8 h MAP was much higher in group 1 (94 +/- 9.2 mm Hg) [+/- SD] compared to either group 2 (71.6 +/- 20.1 mm Hg) or group 3 (49.4 +/- 33.2 mm Hg) [p = 0.01]. This change in MAP correlated with the increase in plasma Cl(-) (R(2) = 0.50, p < 0.0001) and less well with the decrease in pH (R(2) = 0.24, p < 0.001). After 6 h of acidosis, plasma nitrite levels were significantly higher in group 2 animals compared to either group 1 or group 3 animals (p < 0.05). Plasma TNF-alpha, IL-6, or IL-10 levels were not significantly different from control animals.Moderate acidosis (SBE of 5 to 10 mEq/L), induced by HCl infusion, worsened BP and increased plasma nitrate/nitrite levels but had no effect on circulating cytokines in septic rats. However, severe acidosis (SBE of 10 to 15 mEq/L), while still causing hypotension, did not affect plasma nitrate/nitrite levels. |
| 2003 | Peroxisome proliferator activator receptor-gamma ligands, 15-deoxy-Delta(12,14)-prostaglandin J2 and ciglitazone, reduce systemic inflammation in polymicrobial sepsis by modulation of signal transduction pathways. | J Immunol | Peroxisome proliferator activator receptor-gamma (PPARgamma) is a nuclear receptor that controls the expression of several genes involved in metabolic homeostasis. We investigated the role of PPARgamma during the inflammatory response in sepsis by the use of the PPARgamma ligands, 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)) and ciglitazone. Polymicrobial sepsis was induced by cecal ligation and puncture in rats and was associated with hypotension, multiple organ failure, and 50% mortality. PPARgamma expression was markedly reduced in lung and thoracic aorta after sepsis. Immunohistochemistry showed positive staining for nitrotyrosine and poly(ADP-ribose) synthetase in thoracic aortas. Plasma levels of TNF-alpha, IL-6, and IL-10 were increased. Elevated activity of myeloperoxidase was found in lung, colon, and liver, indicating a massive infiltration of neutrophils. These events were preceded by degradation of inhibitor kappaBalpha (IkappaBalpha), activation of IkappaB kinase complex, and c-Jun NH(2)-terminal kinase and, subsequently, activation of NF-kappaB and AP-1 in the lung. In vivo treatment with ciglitazone or 15d-PGJ(2) ameliorated hypotension and survival, blunted cytokine production, and reduced neutrophil infiltration in lung, colon, and liver. These beneficial effects of the PPARgamma ligands were associated with the reduction of IkappaB kinase complex and c-Jun NH(2)-terminal kinase activation and the reduction of NF-kappaB and AP-1 DNA binding in the lung. Furthermore, treatment with ciglitazone or 15d-PGJ(2) up-regulated the expression of PPARgamma in lung and thoracic aorta and abolished nitrotyrosine formation and poly(ADP-ribose) expression in aorta. Our data suggest that PPARgamma ligands attenuate the inflammatory response in sepsis through regulation of the NF-kappaB and AP-1 pathways. |
| 2003 | Reconstituted high-density lipoprotein attenuates organ injury and adhesion molecule expression in a rodent model of endotoxic shock. | Shock | The salutary effects of high-density lipoproteins (HDLs) in animal and human models of endotoxic shock have in the past been attributed to the ability of this lipoprotein to bind to lipopolysaccharide. However, the precise mechanisms for the protective effect of HDL are unclear. The first objective of this study was to determine the effects of HDLs on the organ injury and dysfunction associated with acute severe endotoxemia. Second, to gain insight into the mechanism of action of HDL, we also investigated the effect of HDLs on 1) the expression of P-selectin and intercellular adhesion molecule-1 in the kidneys of rats treated with endotoxin and 2) the rise in the plasma levels of tumor necrosis factor-alpha (TNF-alpha). Rats were given Escherichia coli lipopolysaccharide (6 mg/kg i.v.), pretreated with either vehicle (n = 9) or reconstituted HDL (rHDL; apolipoprotein A-I/phosphatidylcholine proteoliposomes, n = 10), and were monitored for 6 h. Here we report that rHDL attenuates the renal injury and dysfunction caused by endotoxin in the rat. In addition, rHDL reduced the degree of histological tissue injury in the lung, liver and intestine and attenuated the expression of P-selectin and intercellular adhesion molecule-1 in the renal glomerulus. Interestingly, pretreatment of rats with rHDL did not prevent the hypotension nor the rise in plasma levels of TNF-alpha (at 90 min) caused by endotoxin. Thus, rHDL reduces the organ injury/dysfunction, but does not affect the circulatory failure, nor the rise in plasma levels of TNF-alpha caused by endotoxin in the rat. We propose that the mechanisms of these beneficial effects of HDL may be related to direct inhibition of adhesion molecule expression. |
| 2003 | Therapeutic effect of propofol in the treatment of endotoxin-induced shock in rats. | J Huazhong Univ Sci Technolog Med Sci | To assess the potential therapeutic effect of propofol in the treatment of endotoxemia, 76 rats were randomly assigned to 5 groups: control group(A), endotoxemic group(B), pre-treatment group(C), simultaneous treatment group(D) and post-treatment group(E). Five h after endotoxin injection, PO2, pH, MAP, plasma concentrations of Nitrite/nitrate (NO2-/NO3-) and mortality rates were assessed in each group. After the rats were sacrificed, lung tissue was sampled to measure myeloperoxidase (MPO) activity and tumor necrosis factor (TNF)-alpha contents. It was found that endotoxin injection produced progressive hypotension, metabolic acidosis, and a large increase in the plasma NO2-/NO3- concentrations and increased mortality rates in 5 h. Endotoxin injection significantly increased MPO activity and TNF-alpha contents in lung tissue (P < 0.01 or P < 0.05). These changes response to endotoxin were significantly attenuated in the groups B, C and D. But these beneficial effects were blunted in the group E. The results suggest that propofol administration may offer advantages in endotoxemia. |
| 2003 | Propofol ameliorates liver dysfunction and inhibits aortic superoxide level in conscious rats with endotoxic shock. | Eur J Pharmacol | Propofol, widely used as a sedative agent, is known to exert antioxidant and anti-inflammatory effects in vitro. We studied the effects of propofol on hemodynamics and the function of several organs in conscious rats with endotoxemia. Intravenous injection of rats with endotoxin (lipopolysaccharide) caused hypotension, vascular hyporeactivity and tachycardia as well as significant lung, liver and kidney damage. Hepatocellular damage caused by lipopolysaccharide for 6 h was significantly attenuated in the lipopolysaccharide+propofol group. Aortic superoxide anion (O(2)(radical)(-)) production, but not plasma nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) level, was also suppressed by propofol in lipopolysaccharide-injected rats. Light microscopy showed that propofol attenuated the marked infiltration of neutrophils in liver tissues from lipopolysaccharide-injected rats. Moreover, the survival rate of the lipopolysaccharide+propofol group at 16 h was significantly increased when compared with that of the lipopolysaccharide group (53% vs. 12%). These results suggest that inhibition of aortic O(2)(radical)(-) production and amelioration of liver dysfunction contribute to the beneficial effect of propofol in conscious rats with endotoxic shock. |
| 2002 | Comparison of terbutaline and dobutamine in rats with endotoxemia. | Chin J Physiol | It is generally accepted that bacterial endotoxin (lipopolysaccharide, LPS) acts via endogenous mediators leading to endotoxicity. Among these endogenous mediators, tumor necrosis factor-alpha (TNF-alpha) seems to induce all characteristics for endotoxemia. Inhibition of TNF-(alpha production by cAMP-elevating agents has been well documented. Terbutaline (an agonist of beta2-adrenoceptor) and dobutamine (an agonist of beta1-adrenoceptor), both are able to increase intracellular cAMP via activation of adenylate cyclase, were examined in the anesthetized rat with endotoxemia. Terbutaline or dobutamine was administered to the rat at 30 min after LPS injection. Hemodynamic changes and plasma TNF-alpha and nitrate (the end product of nitric oxide [NO]) levels as well as superoxide anion (O2*-) production in the aorta were examined in this study. Results showed that terbutaline, but not dobutamine, improved the circulatory failure (e.g. hypotension and vascular hyporeactivity) in rats with endotoxemia. In addition, both terbutaline and dobutamine reduced the plasma TNF-alpha level, but only terbutaline attenuated the aortic O2*- production in these endotoxemic rats. The beneficial effect of terbutaline in endotoxemic animals was associated with a reduction in plasma TNF-alpha and aortic O2*-, but not in plasma NO. |
| 2003 | Inhibition by terbutaline of nitric oxide and superoxide anion levels of endotoxin-induced organs injury in the anesthetized rat. | Shock | Despite the fact that septic shock is characterized by a decrease in systemic vascular resistance, the main cause of death is due to multiple organ failure. The organ dysfunction is usually attributed to cell death caused by overproduction of free radicals derived from inflammation. In the host infected by endotoxin (lipopolysaccharide, LPS), the expression and release of proinflammatory tumor necrosis factor-alpha (TNF-alpha) rapidly increases, and the formation of free radicals (e.g., superoxide anion [O2*-] and nitric oxide [NO*] in the present study) are inevitably overproduced. In this study, we present evidence that overall treatment of LPS rats with terbutaline, a beta2-adrenoceptor agonist, attenuates the delayed hypotension and ameliorates the tachycardia. Overproduction of TNF-alpha and NO* (produced by inducible NO synthase [iNOS] examined by Western blot analysis in the lung and the liver) is inhibited by treatment of LPS rats with terbutaline. In addition, treatment of endotoxemic rats with terbutaline also reduces the O2*- levels in the lung and the liver. Terbutaline also improves the liver (assessed by aspartate aminotransferase, alanine aminotransferase, total bilirubin, and albumin/globulin) and kidney (assessed by creatinine and uric acid) dysfunction induced by endotoxin. These findings suggest that the amelioration of circulatory failure and organs injury by terbutaline is associated with its suppression in TNF-alpha, O2*- and NO (via iNOS) production in animals with endotoxic shock. |
| 2003 | Efferent vagal fibre stimulation blunts nuclear factor-kappaB activation and protects against hypovolemic hemorrhagic shock. | Circulation | We investigated whether electrical stimulation (STIM) of efferent vagus nerves may suppress nuclear factor (NF)-kappaB activation and the inflammatory cascade in hemorrhagic (Hem) shock.Rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Hem shock was induced by intermittent withdrawing of blood until mean arterial pressure stabilized within the range of 35 to 40 mm Hg. Application of constant voltage pulses to the caudal vagus ends (STIM; 5 V, 2 ms, 1 Hz for 12 minutes, 5 minutes after mean arterial pressure stabilization) increased survival time (VGX+Hem+Sham STIM=38+/-3 minutes; VGX+Hem+STIM >180 minutes), reverted the marked hypotension (VGX+Hem+Sham STIM=33+/-3 mm Hg; VGX+Hem+STIM=66+/-5 mm Hg), inhibited IkappaBalpha liver loss, and blunted the augmented NF-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX+Hem+Sham STIM=1.42+/-0.5 amount of TNF-alpha m-RNA; VGX+Hem+STIM=0.51+/-0.2 amount of TNF-alpha mRNA), and reduced plasma TNF-alpha (VGX+Hem+Sham STIM=190+/-24 pg/mL; VGX+Hem+STIM=87+/-15 pg/mL). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation.Our results show a parasympathetic inhibition of NF-kappaB by which the brain opposes NF-kappaB activation in the liver and modulates the inflammatory response during acute hypovolemic hemorrhagic shock. |
| 2002 | Interleukin (IL)-8 and growth related oncogene-alpha in severe endotoxemia and the effects of a tumor necrosis factor-alpha/IL-1beta inhibitor on these chemokines. | Exp Mol Pathol | FR167653 inhibits the production of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta, powerful inducers of CXC chemokines IL-8 and growth related oncogene (GRO)-alpha. The production of IL-8 and GRO-alpha was investigated and the effects of FR167653 were examined in a rabbit model of endotoxin shock. Male New Zealand rabbits were given endotoxin at a dose sufficient to induce DIC. Three groups of rabbits received FR167653 at different doses. TNF-alpha, IL-1beta, IL-8, and GRO-alpha levels were measured, several pathologic features were evaluated, and the results were compared with those obtained in control rabbits, which received only endotoxin. Endotoxin increased serum levels of IL-8 and GRO-alpha, which were associated with hypotension, renal dysfunction, and mortality, peaking at 4 h. FR167653 improved mortality, an event that was associated with decreased levels of not only TNF-alpha and IL-1beta but also IL-8 and GRO-alpha. TNF-alpha peaked at 2 h, at a time point before IL-8 and GRO-alpha reached their peak, and the TNF-alpha level was tightly correlated with that of IL-8 and GRO-alpha. Altogether, these data suggest the possible involvement of IL-8 and GRO-alpha in endotoxin shock, and FR167653 may foster a beneficial outcome in part by modulating the chemokines level by inhibiting TNF-alpha and IL-1beta. |
| 2003 | [Induction of left ventricular remodeling and dysfunction in the recipient heart following donor heart myocardial infarction: new insights into the pathological role of tumor necrosis factor-alpha from a novel heterotopic transplant-coronary ligation model]. | J Cardiol | Neurohormonal and cytokine activation after acute myocardial infarction contribute to cardiac remodeling. This study aimed to examine the effects of tumor necrotic factor (TNF)-alpha and angiotensin II on cardiac remodeling and dysfunction after acute myocardial infarction.We performed isogenic heterotopic cardiac transplantation and simultaneous coronary ligation to produce myocardial infarction in the donor heart, and to evaluate the hearts of both donors and recipients in Lewis rats. The recipients in the ligation group showed significant body-weight loss, hyperthermia, tachycardia, hypotension and leukocytosis at day 7. A significant decrease in left ventricular fractional shortening and + dP/dt, and a significant increase in left ventricular enddiastolic dimension/body weight and left ventricular enddiastolic pressure were also observed in the recipient hearts in the ligation group at day 7. With the exception of the increased perivascular fibrosis, these recipient responses were no longer seen at day 21. TNF-alpha was significantly elevated not only in the plasma but also in the recipient hearts in the ligation group at day 7. In contrast, angiotensin II was significantly increased only in the infarct region of the donor hearts, but not in the plasma. Further, the recipients' transient left ventricular remodeling and dysfunction were completely abolished by the intravenous administration of chimeric TNF-alpha soluble receptor.We developed a novel heterotopic cardiac transplantation-coronary ligation model capable of inducing myocardial infarction in the absence of downstream hemodynamic effects, and allowing differential quantification of indexes of cardiac remodeling in vivo, such as the local and remote effects of angiotensin II and TNF-alpha on cardiac remodeling. Modification of activated cytokines, such as TNF-alpha induced by cardiac ischemic stress, might be a beneficial strategy for the treatment of cardiac dysfunction and subsequent cardiac remodeling after acute myocardial infarction. |
| 2003 | Bioartificial kidney ameliorates gram-negative bacteria-induced septic shock in uremic animals. | J Am Soc Nephrol | The bioartificial kidney (BAK) consists of a conventional hemofiltration cartridge in series with a renal tubule assist device (RAD) containing 10(9) porcine renal proximal tubule cells. BAK replaces filtration, transport, and metabolic and endocrinologic activities of a kidney. Previous work in an acutely uremic dog model demonstrated that BAK ameliorated endotoxin (lipopolysaccharide [LPS])-induced hypotension and altered plasma cytokine levels. To further assess the role of BAK in sepsis in acute renal failure, dogs were nephrectomized and 48 h later administered intraperitoneally with 30 x 10(10) bacteria/kg of E. coli. One hour after bacterial administration, animals were placed in a continuous venovenous hemofiltration circuit with either a sham RAD without cells (n = 6) or a RAD with cells (n = 6). BP, cardiac output, heart rate, pulmonary capillary wedge pressure, and systemic vascular resistance were measured throughout the study. All animals tested were in renal failure, with blood urea nitrogen and serum creatinine concentrations greater than 60 and 6 mg/dl, respectively. RAD treatment maintained significantly better cardiovascular performance, as determined by arterial BP (P < 0.05) and cardiac output (P < 0.02), for longer periods than sham RAD therapy. Consistently, all sham RAD-treated animals, except one, expired within 2 to 9 h after bacterial administration, whereas all RAD-treated animals survived more than 10 h. Plasma levels of TNF-alpha, IL-10, and C-reactive protein (CRP) were measured during cell RAD and sham RAD treatment. IL-10 levels were significantly higher (P < 0.01) during the entire treatment interval in the RAD animals compared with sham controls. These data demonstrated in a pilot large animal experiment that the BAK with RAD altered plasma cytokine levels in acutely uremic animals with septic shock. This change was associated with improved cardiovascular performance and increased survival time. These results demonstrate that the addition of cell therapy to hemofiltration in an acutely uremic animal model with septic shock ameliorates cardiovascular dysfunction, alters systemic cytokine balance, and improves survival time. |
| 2002 | IgM-enriched immunoglobulin preparation for immunoprophylaxis in cardiac surgery. | Eur J Med Res | Evaluating the effects of prophylactic administration of IgM-enriched immunoglobulins (IVIG) on immunological- and clinical parameters in cardiac surgical patients.41 patients were randomized to receive either an IgM-enriched immunoglobulin (Pentaglobin(R)) preparation (1,300 ml immunoglobulin, equivalent to 65 g protein) combined with routine antibiotic prophylaxis (Group A; n = 20, 1 drop-out), or routine antibiotic prophylaxis plus placebo (Group B; n = 20). Patients were comparable with respect to their APACHE II score, comorbidity, coronary risk, operating time, clamp, and ischemic time. Endotoxin and endotoxin neutralizing capacity (ENC) were determined by a kinetic turbidimetric Limulus amebocyte lysate (LAL) assay with internal standardization. Serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF)-alpha, soluble TNF-Receptor I (sTNF-R1), and interleukin-10 (IL-10) were determined by ELISA. Data analysis was performed by area under the curve (AUC) calculation and ANOVA for endotoxin neutralizing capacity and by ANOVA for all other cases.All patients survived. Endotoxin plasma levels were generally but not significantly higher in group A than in controls, while the difference in endotoxin neutralizing capacity (ENC) reached significance. IL-6, TNF-alpha, IL-10 and TNF-R1 were not different between both groups, however. There were significantly less patients with signs of inflammation (fever, leukocytosis, hypotension) in group A (group A n = 2; group B n = 9; p<0.05). This was paralleled by a slightly reduced hospitalization period in group A patients compared to group B patients (A:12.05 +/- 3.66 vs. B:13.45 +/- 3.72 days; n.s.). All data are given as mean +/- standard deviation (SD).The results of this study support that IgM-enriched IVIG preparation are effective when used prophylactically in patients undergoing procedures with cardiopulmonary bypass. The mechanisms of endotoxin neutralization and the effect of the host immune status on the efficacy of IVIG treatment remain to be elucidated. |
| 2002 | Pirfenidone attenuates ischaemia-reperfusion injury in the rat small intestine. | Clin Exp Pharmacol Physiol | 1. Pirfenidone, an antifibrotic compound with anti-inflammatory effects, has been investigated in a rat model of acute experimental ischaemia-reperfusion injury of the small intestine. 2. Occlusion of the superior mesenteric artery in young adult female rats for 30 min followed by reperfusion for 120 min induced significant local and systemic effects, including tissue haemorrhage with oedema, elevated serum concentrations of tumour necrosis factor (TNF)-alpha, neutropenia, hypotension and bradycardia. 3. Administration of pirfenidone (200 mg/kg, p.o., i.v. or i.p.) 30 min before occlusion completely inhibited the increase in serum TNF-alpha concentrations. Pirfenidone inhibited, but did not completely prevent, tissue damage in the small intestine, as well as hypotension and oedema, but neutropenia and bradycardia were not significantly changed by treatment. 4. Thus, pirfenidone effectively moderates both local and some systemic effects of ischaemia-reperfusion injury in the rat small intestine model. |
| 2002 | Soluble tumor necrosis factor receptor p55 predicts cytokinemia and systemic inflammatory response after cardiopulmonary bypass. | Crit Care Med | To examine the behavior of soluble tumor necrosis factor (TNF) receptors in circulation before and after cardiopulmonary bypass and the relationship to the development of cytokinemia and acute complications comprising systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). The predictive value of soluble TNF receptor is assessed herein.Prospective study comparing prebypass and postbypass levels in patients with and without complications indicative of SIRS and MODS.Cardiac surgical intensive care unit in a tertiary care hospital.A total of 20 pediatric patients who underwent cardiopulmonary bypass during open heart surgery.Blood samples were collected from catheters before and 2 hrs and 24 hrs after the onset of bypass.We measured plasma levels of soluble TNF receptors by using enzyme-linked immunosorbent assay in 20 patients before and after cardiopulmonary bypass. Clinical data, including duration of bypass and tests or signs indicative of SIRS/MODS, were collected. Soluble TNF receptor I (p55 sR), significantly increased (2241 +/- 312 pg/mL) at 2 hrs after bypass (p <.0005) and remained elevated (2826 +/- 695 pg/mL) at 1 day after bypass (p <.005) when compared with prebypass levels (725 +/- 130 pg/mL). Patients with the acute complications of SIRS/MODS had a higher ratio of postbypass to prebypass p55 sR levels (5.0-fold, p <.001) when compared with patients with no SIRS/MODS (1.75-fold). Remarkably, before surgery, levels of TNF p55 sR predict both cytokinemia (r =.67 to.73, p <.05) and SIRS/MODS (p <.01). The prebypass levels of TNF p55 sR were consistently higher (range, 1000-1400 pg/mL) in patients who subsequently developed SIRS/MODS than the levels (range, 400-570 pg/mL) in patients who did not develop SIRS/MODS. Hypotension, respiratory dysfunctions, and coagulopathy were particularly more prevailing (p <.005) among the complications that were associated with high prebypass levels of TNF p55 sR.Soluble TNF receptor p55 can be employed as a predictive marker for cytokinemia and the development of SIRS/MODS that may arise from a major insult to the body such as cardiopulmonary bypass. |
| Oxaliplatin may induce cytokine-release syndrome in colorectal cancer patients. | J Biol Regul Homeost Agents | Oxaliplatin, a third-generation platinum analogue, is a novel compound with proven anti-tumor activity in colorectal cancer. Moreover, oxaliplatin appears to be relatively well tolerated and easy to handle, even on an outpatient basis.Five advanced colorectal cancer patients treated with oxaliplatin-based chemotherapy developed, after the end of oxaliplatin infusion, similar idiosyncratic reactions characterized by chills, high fever, hypotension, abdominal pain, nausea and often diarrhoea. Venous blood for IL-6 and TNF-alpha assessment was drawn just after the beginning of the reaction and 15 and 30 minutes later. After drawing the third venous sample, intravenous dexamethasone (8 mg) was administered and the drawing of other two venous samples was performed (180 and 360 minutes after the beginning of the reaction).TNF-alpha and IL-6 serum concentrations significantly decreased after steroid therapy administration. The decrease of TNF-alpha and IL-6 levels went along with the clinical complete regression of symptoms and signs in all the 5 patients. No statistically significant correlation was found between other laboratory parameters and basal cytokine levels or cytokine decrease after steroid therapy.Our results clearly show that that idiosyncratic reaction observed in colorectal cancer patients after oxaliplatin infusion may be due to a massive release of cytokines such as TNF-alpha and IL-6. Symptom regression following steroid therapy administration went along with significant decrease of cytokines levels, confirming that TNF-alpha and IL-6 play a role in the pathogenesis of this reaction. |
| 2002 | Inflammatory cytokines and lipopolysaccharide induce Fas-mediated apoptosis in renal tubular cells. | Nephron | Increased susceptibility of the kidney to acute renal failure (ARF) in the setting of sepsis even in the absence of systemic hypotension is well known. In the hypothesis that the proinflammatory cytokines and lipopolysaccharide (LPS) in gram-negative sepsis can directly cause renal tubular cell apoptosis via Fas- and caspase-mediated pathways, we examined apoptosis and Fas, Fas ligand, FADD expression, as well as PARP cleavage in cultured human proximal tubular cells under the cytokine and LPS-stimulated conditions.HK-2 cell, immortalized human proximal tubular cell lines, were treated with 5 and 30 ng/ml of tumor necrosis factor-alpha (TNF-alpha), 5 and 20 ng/ml of interleukin-1beta (IL-1beta) and 30 ng/ml LPS for 24 h. Fas expression was examined by RT-PCR and Fas ligand, Fas-associated protein with death domain (FADD) and poly ADP ribose polymerase (PARP) cleavage were examined by Western blot analysis. Apoptosis was assessed by flow cytometer using Annexin V-FITC and propidium iodide (PI) staining and also by terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) methods.Fas mRNA expression (ratio of Fas/L-19) increased in the TNF-alpha 5, 30 ng/ml and LPS treated group (p < 0.01, p < 0.01, p = 0.02), but there was no difference between the low- and high-dose TNF-alpha groups. Fas ligand protein expression did not increase in the low-dose TNF-alpha treated group, but it increased significantly in the high-dose TNF-alpha treated group (p < 0.01), IL-1beta- and LPS-treated groups (p < 0.01, p = 0.01, p < 0.01, p = 0.02). The intracellular adaptor protein, FADD expression also increased significantly in the high-dose TNF-alpha- and IL-beta-treated groups (p = 0.04, p = 0.04), but in the low-dose TNF-alpha and IL-beta treated group, it did not show statistically significant differences. In the LPS group, FADD expression also showed an increased tendency, but it was not statistically significant (p = 0.09). Western blot for PARP, a DNA repair enzyme mainly cleaved by caspase 3, showed increased 89- and 24-kD PARP cleavage products in TNF-alpha, IL-1beta and LPS treated cells. The degree of apoptosis examined by DNA fragmentation and translocation of membrane phosphatidyl serine significantly increased in cytokines and LPS treated groups.These results suggest that Fas- and caspase-mediated apoptosis of tubular cells by inflammatory cytokines and LPS can be one of the possible mechanisms of renal dysfunction in endotoxemia. |
| 2002 | Inhibition of nuclear factor-kappaB activation by IRFI 042, protects against endotoxin-induced shock. | Cardiovasc Res | The aim of our study was to investigate the effect of IRFI 042, a novel dual vitamin E-like antioxidant, on nuclear factor-kappaB (NF-kappaB) activation, TNF-alpha gene priming and on the release of the mature protein during endotoxin shock.Endotoxin shock was produced in male rats by a single intravenous (i.v.) injection of 20 mg kg(-1) of Salmonella enteritidis lipopolysaccharide (LPS). Survival rate, mean arterial blood pressure, serum TNF-alpha and plasma malondialdehyde (MAL) levels were investigated. We then evaluated in the liver TNF-alpha mRNA levels, NF-kappaB binding activity and the inhibitory protein IkappaBalpha. Moreover we studied in LPS stimulated (50 microg ml(-1)) peritoneal macrophages (Mphi), NF-kappaB activation, cytoplasmic IkappaB-alpha degradation, the message for TNF-alpha, and TNF-alpha and MAL levels.LPS administration reduced survival rate (0%, 72 h after LPS administration), decreased mean arterial blood pressure, augmented serum TNF-alpha (60+/-11 ng ml(-1)) and enhanced plasma malondialdehyde (MAL) levels (55+/-7.1 nmol l(-1)). LPS shocked rats also had increased TNF-alpha mRNA levels, augmented liver NF-kappaB binding activity in the nucleus and decreased levels of the inhibitory protein IkappaBalpha. In addition, in vitro LPS stimulation (50 microg ml(-1)) significantly induced NF-kappaB activation and cytoplasmic IkappaBalpha degradation in Mphi, enhanced TNF-alpha mRNA levels and increased Mphi TNF-alpha and MAL. Treatment with IRFI 042 (20 mg kg(-1), i.v., 5 min after endotoxin challenge) protected against LPS-induced lethality (90% survival rate 24 h and 80% survival rate 72 h after LPS injection, respectively), reduced hypotension, blunted plasma MAL (9.0+/-0.9 nmol l(-1)) and decreased serum TNF-alpha (15+/-3 ng ml(-1)). The antioxidant also inhibited the loss of IkappaBalpha protein from the hepatic cytoplasm, blunted the increased NF-kappaB binding activity in the liver and decreased hepatic liver mRNA for TNF-alpha. Furthermore 'in vitro' IRFI 042 (50 microM) significantly inhibited activation of NF-kappaB through inhibition of IkappaBalpha degradation, reduced the amount of TNF-alpha mRNA, decreased LPS-induced TNF-alpha release and blunted lipid peroxidation (MAL) in LPS stimulated Mphi.These data suggest that IRFI 042 blocks the activation of NF-kappaB, reduces TNF-alpha mRNA levels, and finally reverses endotoxic shock. |
| 2002 | Effect of fentanyl on TNF-alpha and IL-1beta levels during global ischemia/reperfusion in rats. | Int J Tissue React | To reduce surgical stress, fentanyl is frequently used for neurosurgical procedures in which focal and/or global ischemia may occur. However, the effect of fentanyl on cytokine levels during ischemia/reperfusion is still uncertain. The goal of this study was to evaluate the effect of fentanyl infusion on levels of the proinflammatory cytokines, tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta, during global cerebral ischemia/reperfusion in rats using the intracerebral microdialysis technique. Forty male Sprague-Dawley rats weighing 280-320 g were randomly assigned to each of four groups: group 1 (no fentanyl infusion and only ischemia/reperfusion); group 2 (1.5 ng/ml of fentanyl infusion during ischemia/reperfusion) and group 3 (3 ng/ml of fentanyl infusion during ischemia/reperfusion) (n=5 in each group). The rats were anesthetized with an intraperitoneal injection of pentobarbital (50 mg/kg). They were then intubated and ventilated with room air using an animal ventilator. A CMA-12 probe was inserted into the left hippocampal CA-1 region according to the guidelines. Artificial cerebrospinal fluid was run from the inserted microdialysis probe and infused with or without fentanyl at 3 microl/min using a microinjection syringe pump during ischemia/reperfusion. Ischemia was induced by clamping the carotid arteries. Hemorrhagic hypotension was induced for 17 min via the femoral artery, and reperfusion was accomplished by unclamping the sling and reinfusing the blood via the femoral artery. After 2 h of stabilization, the microdialysate was collected 10 times every 17 min, just before ischemia (control), after ischemia (I) and after reperfusion (R1-R8), and stored at -80 degrees C until analysis using high-performance liquid chromatography During global ischemia/reperfusion, TNF-alpha and IL-1beta significantly increased at reperfusion (R5) compared with the control value (p < 0.05). However, in both cases of fentanyl infusion, TNF-alpha and IL-1beta showed no increase compared with the control value. Fentanyl inhibited an increase of the proinflammatory cytokines, TNF-alpha and IL-1beta levels, during global cerebral ischemia/reperfusion in rats. |
| 2002 | The effect of linarin on LPS-induced cytokine production and nitric oxide inhibition in murine macrophages cell line RAW264.7. | Arch Pharm Res | The herb, Chrysanthemum zawadskii var, latilobum commomly known as Gu-Jul-Cho in Korea, used in traditional medicine to treat pneumonia, bronchitis, cough, common cold, pharyngitis, bladder-related disorders, gastroenteric disorders, and hypertension. Linarin is the main active compound and the biological mechanisms of its activity are unclear. It is believed that effects of this herb may be exerted through the pluripotent effectors of linarin due to its ability to treat a variety of afflictions. In this study, the effects of linarin on the mouse macrophages cell line, RAW 264.7, were investigated. It was found that linarin could activate macrophages by producing cytokines. Monocytes and tissue macrophages produce at least two groups of protein mediators of inflammation, interleukin 1 (IL-1) and the tumor necrosis factor (TNF). Recent studies have shown that TNF and IL-1 modulate the inflammatory function of endothelial cells, leukocytes, and fibroblasts. TNF-alpha production by macrophages treated with linarin occured in a dose dependent manner. However, IL-1 production was largely unaffected by this natural product. This study demonstrated the ability of linarin to activate macrophages both directly and indirectly. Linarin also affect both cytokine production and nitric oxide inhibition, in addition to the expression of some surface molecules. Nitric oxide (NO), derived from L-argin-ine, is produced by two forms(constitutive and inducible) of nitric oxide synthase (NOS). The NO produced in large amounts by inducible NOS is known to be responsible for the vasodilation and hypotension observed in septic shock. Linarin was found to inhibit NO production in the LPS-activated RAW 264.7 cells. Linarin may be a useful candidate as a new drug for treating endotoxemia and the inflammation accompanied by NO overproduction. The linarin-treated total lymphocytes exhibited cytotoxicity in a dose dependent manner between 20 microg/ml and 40 microg/ml. These results suggest that linarin may function through macrophage activation. |
| 2002 | [Inhibitory effect of cholecystokinin-octapeptide on production of cytokines in the lung of endotoxic shock rats]. | Sheng Li Xue Bao | To study the effect of cholecystokinin-octapeptide (CCK-8) on systemic hypotension and cytokine production in serum and lung of endotoxic shock (ES) rats induced by lipopolysaccharide (LPS) and investigate its signal transduction mechanism of p38 mitogen-activated protein kinase (MAPK), the changes in mean arterial pressure (MAP) were observed by using a polygraph in four groups of SD rats: group of LPS (8 mg/kg i.v.) induced ES, group of CCK-8 (40 microg/kg i.v.) pretreatment 10 min before LPS (8 mg/kg) administration, group of CCK-8 (40 microg/kg i.v.) only, and normal saline (control) group; the contents of proinflammatory cytokines (TNF-alpha, IL-1 beta and IL-6) in the lung and serum were assayed using ELISA kits; and p38 MAPK was detected by Western blot. The results showed that CCK-8 alleviated LPS-induced decrease in MAP of rats; compared with the control, LPS elevated the levels of TNF-alpha, IL-1 beta and IL-6 in serum and lung significantly, while CCK-8 significantly inhibited the LPS-induced increases in TNF-alpha, IL-1 beta and IL-6 in serum and lung. The activation of p38 MAPK in the lung of ES rats was enhanced by CCK-8 pretreatment. These results suggest that CCK-8 can alleviate the LPS-induced decrease in MAP of ES rats and exert an inhibitory effect on the overproduction of proinflammatory cytokines, and that p38 MAPK may be involved in its signal transduction mechanisms. |
| 2002 | Antithrombin prevents endotoxin-induced hypotension by inhibiting the induction of nitric oxide synthase in rats. | Blood | Antithrombin (AT) prevents Escherichia coli-induced hypotension in animal models of sepsis, and it further reduces the mortality of patients with septic shock. In the present study, we examined whether AT may prevent the endotoxin (ET)-induced hypotension by promoting the endothelial release of prostacyclin (PGI(2)) in rats. Intravenous administration of AT (250 U/kg) prevented both hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-) in rats given ET. Lung expression of messenger RNA (mRNA) for tumor necrosis factor-alpha (TNF-alpha) was transiently increased after ET administration, followed by the increases in lung tissue levels of TNF-alpha. Both the lung activity of the inducible form of nitric oxide synthase (iNOS) and the lung expression of iNOS mRNA in animals administered ET were gradually increased after the TNF-alpha mRNA expression had peaked. Administration of AT significantly inhibited these increases. Neither DEGR-F.Xa, a selective inhibitor of thrombin generation, nor Trp(49)-modified AT, which is not capable of promoting the endothelial release of PGI(2), showed any effects on these changes induced by ET. Administration of antirat TNF-alpha antibody produced effects similar to those induced by AT. Indomethacin pretreatment abrogated the effects induced by AT. Iloprost, a stable derivative of PGI(2), produced effects similar to those of AT. These findings suggested that AT prevents the ET-induced hypotension by inhibiting the induction of iNOS through inhibiting TNF-alpha production. These effects of AT could be mediated by the promotion of endothelial release of PGI(2) and might at least partly explain the therapeutic effects for septic shock. |
| 2002 | CCK-8 inhibits expression of TNF-alpha in the spleen of endotoxic shock rats and signal transduction mechanism of p38 MAPK. | World J Gastroenterol | To study the effect of sulfated cholecystokinin-octapeptide (CCK-8) on systemic hypotension, gene and protein expression of TNF-alpha in the spleen of lipopolysaccharide (LPS)-induced endotoxic shock (ES) rats, and further investigate the signal transduction mechanism of p38 mitogen-activated protein kinase (MAPK).The changes of blood pressure were observed using physiological record instrument in the four groups of rats: LPS (8 mg x kg(-1), iv), CCK-8 (40 microg x kg(-1), iv) pretreatment 10 min before LPS (8 mg x kg(-1)), CCK-8 (40 microg x kg(-1), iv) or normal saline (control) group. The content of TNF-alpha in the spleen was assayed 2 h after LPS administration using ELISA kit and the expression of TNF-alpha mRNA was examined 30 min, 2 h and 6 h after LPS administration by reverse transcribed polymerase chain reaction (RT-PCR). Activation of p38 MAPK was detected with Western blot 30 min after LPS administration.CCK-8 reversed LPS-induced decrease of mean arterial pressure (MAP) in rats. The content of TNF-alpha in the spleen was (282+/-30) ng x L(-1) in control group, while it increased to (941+/-149) ng x L(-1) in LPS group, P<0.01. CCK-8 significantly inhibited the LPS-induced increase of TNF-alpha content in spleen. It decreased to (462 +/-87) ng x L(-1) in CCK-8+LPS group, P<0.01. The expression of TNF-alpha mRNA 30 min and 2 h after treatment was stronger in LPS group, while it was lowered after CCK-8 pretreatment. The p38 MAPK expression increased significantly in LPS group (5.84 times of control) and CCK-8 increased the activation of p38 MAPK in ES rats (10.74 times of control).CCK-8 reverses the decrease of MAP in ES rats and has inhibitory effect on the gene and protein expression of TNF-alpha in spleen, and p38 MAPK may be involved in its signal transduction mechanisms. |
| 2001 | Effect of cholecystokinin on cytokines during endotoxic shock in rats. | World J Gastroenterol | To study the effect of cholecystokinin-octapeptide (CCK-8) on systemic hypotension and cytokine production in lipopolysaccharide (LPS)-induced endotoxic shock (ES) rats.The changes of blood pressure were observed using physiological record instrument in four groups of rats: LPS (8mg.kg(-1),iv) induced ES; CCK-8 (40 microg.kg(-1), iv) pretreatment 10 min before LPS (8mg.kg(-1)); CCK-8 (40 micro.kg(-1), iv) or normal saline (control) groups. Differences in tissue and circulating specificity of the proinflammatory cytokines (TNF-alpha, IL-1beta and IL-6) were assayed with ELISA kits.CCK-8 reversed LPS-induced decrease of mean artery blood pressure (MABP) in rats. Compared with control, LPS elevated the serum level of IL-6 significantly (3567 +/- 687 ng.L(-1) vs 128 +/- 22 ng.L(-1), P<0.01), while contents of TNF-alpha and IL-1beta elevated significantly (277 +/- 86 ng.L(-1) vs not detectable and 43 +/- 9 ng.L(-1) vsnot detectable, P<0.01) but less extent than IL-6. CCK-8 significantly inhibited the LPS-induced increase in serum TNF-alpha IL-1beta and IL-6. LPS elevated spleen and lung content of IL-1beta significantly (5184 +/- 85 ng.L(-1) vs 1047 +/- 21 ng.L(-1) and 4050 +/- 614 ng.L(-1) vs not detectable, P<0.01), while levels of TNF-alpha and IL-6 also rose significantly but in less extent than IL-1beta. CCK-8 inhibited the LPS-induced increase of the cytokines in spleen and lung. In the heart, CCK-8 significantly inhibited LPS-induced increase of TNF-alpha (864 +/- 123 ng.L(-1) in CCK-8+LPS group vs 1599 +/- 227 ng.L(-1) in LPS group, P < 0.01), and IL-1beta (282 +/- 93 ng.L(-1) in CCK-8+LPS group vs 621 +/- 145ng.L(-1) in LPS group, P < 0.01).CCK-8 reverses ES, which may be related to its inhibitory effect on the overproduction of cytokines. |
| 2002 | Evidence for a role of nuclear factor-kappaB in acute hypovolemic hemorrhagic shock. | Surgery | In acute hypovolemic shock, a rapid systemic release of the inflammatory cytokine tumor necrosis factor (TNF-alpha) contributes to vascular failure. Nuclear factor kappaB (NF-kappaB) is an ubiquitous rapid-response transcription factor involved in inflammatory reactions and exerts its effect by expressing cytokines, chemokines, and cell adhesion molecules. The purpose of this study was to evaluate the role of NF-kappaB in acute hypovolemic hemorrhagic shock.Hemorrhagic shock was induced in anesthetized male rats by intermittently withdrawing blood from an iliac catheter for 20 minutes (bleeding period) until mean arterial blood pressure (MAP) decreased and stabilized within the range of 20 to 30 mm Hg. Two minutes after bleeding was discontinued the rats received tacrolimus (100 microg/kg), an inhibitor of NF-kappaB activation, or its vehicle. We then evaluated survival rate and survival time, liver NF-kappaB activation by means of electrophoretic mobility shift assay, liver IkappaBalpha protein in the cytoplasm, hepatic TNF-alpha messenger RNA expression, plasma TNF-alpha, arterial blood pressure, and the contractile response of aortic rings to phenylephrine.Rats that underwent hemorrhagic shock died 28+/-2 minutes after bleeding was discontinued, experienced marked hypotension (MAP, 20-30 mm Hg), and had enhanced plasma levels of TNF-alpha (218 +/- 28 pg/mL 20 minutes after bleeding was discontinued). Aortas taken 20 minutes after bleeding was discontinued in rats that underwent hemorrhagic shock showed marked hyporeactivity to phenylephrine (1 nmol/L-10 micromol/L) compared with aortas harvested from sham shocked rats. Rats that underwent hemorrhagic shock also had increased levels of TNF-alpha messenger RNA in the liver. Furthermore, electrophoretic mobility shift assay showed that liver NF-kappaB binding activity increased in the nucleus, and Western blot analysis suggested that the levels of inhibitory IkappaBalpha protein in the cytoplasm decreased. Tacrolimus (100 microg/kg, administered 2 minutes after bleeding was discontinued) inhibited the loss of IkappaBalpha protein from the cytoplasm and prevented NF-kappaB binding activity in the nucleus. Moreover, tacrolimus increased survival time (118 +/- 7 minutes; P <.01) and survival rate (vehicle = 0 and tacrolimus = 90% 240 minutes after bleeding was discontinued), reverted the marked hypotension, decreased liver messenger RNA for TNF-alpha reduced plasma TNF-alpha (35 +/- 6 pg/mL), and restored the hyporeactivity to phenylephrine to control values.Our results suggest that acute blood loss (50% of the estimated total blood volume during a 20-minute period) causes activation of NF-kappaB and that tacrolimus, by inhibiting this transcription factor, protects against acute hypovolemic shock. |
| 2001 | Campath-1H (anti-CD52) monoclonal antibody therapy in lymphoproliferative disorders. | Med Oncol | Campath-1H is a humanized monoclonal antibody targeted against the CDw52 membrane antigen of lymphocytes, which causes complement and antibody-dependent cell-mediated cytotoxicity. Campath-1H has been used in B-chronic lymphocytic leukemia (B-CLL), T-prolymphocytic leukemia (T-PLL), and low-grade non-Hodgkin's lymphoma (LGNHL). Campath-1H is administered intravenously thrice weekly for up to 12 wk, at an initial dose of 3 mg, escalated to 10 and 30 mg. The responses (complete [CR] and partial [PR]) obtained in untreated B-CLL patients are of the order of 90%. In previously treated B-CLL patients, responses are of the order of approximately 40%, with 2-4% CRs. Responses are more prominent in the blood and bone marrow compared to the lymph nodes. The median duration of response is 9-12 mo. Because of the antibody's higher activity on circulating lymphocytes, it has been used for in vivo purging of residual disease in B-CLL, followed by autologous stem-cell transplantation. In heavily pretreated advanced stage LGNHL, response is achieved only in 14% of cases with B-phenotype; a 50% response rate is noted in mycosis fungoides. In T-PLL, the CR rate is approximately 60%. Promising results have been reported in a small number of patients with refractory autoimmune thrombocytopenia of lymphoproliferative disorders. The main complications of Campath-1H treatment are caused by tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 release, usually during the first intravenous infusion, and include fever, rigor, nausea, vomiting, and hypotension responsive to steroids. These side effects are usually less severe with subsequent infusions and can be prevented by paracetamol and antihistamines. Immunosupression resulting from normal B- and T-lymphocyte depletion is frequent, resulting in an increased risk for opportunistic infections. More clinical trials in a larger number of patients are necessary to determine the exact role and indications of Campath-1H in lymphoproliferative disorders. |
| 2001 | Recombinant tissue factor pathway inhibitor prevents lipopolysaccharide-induced systemic hypotension in rats by inhibiting excessive production of nitric oxide. | Thromb Haemost | Excessive production of nitric oxide (NO) by the inducible form of NO synthase (iNOS) plays a key role in the development of endotoxin shock. Tumor necrosis factor-alpha (TNF-alpha) induces iNOS, thereby contributing to the development of shock. We recently reported that recombinant tissue factor pathway inhibitor (r-TFPI), an important inhibitor of the extrinsic pathway of the coagulation system, inhibits TNF-alpha production by monocytes. In this study, we investigated whether r-TFPI could ameliorate hypotension by inhibiting excessive production of NO in rats given lipopolysaccharide (LPS). Pretreatment of animals with r-TFPI prevented LPS-induced hypotension. Recombinant TFPI significantly inhibited the increases in both the plasma levels of NO2-/NO3- and lung iNOS activity 3 h after LPS administration. Expression of iNOS mRNA in the lung was also inhibited by intravenous administration of r-TFPI. However, neither DX-9065a, a selective inhibitor of factor Xa, nor an inactive derivative of factor VIIa (DEGR-F.Vlla) that selectively inhibits factor VIIa activity, had any effect on LPS-induced hypotension despite their potent anticoagulant effects. Moreover, neither the plasma levels of NO2-/NO3- nor lung iNOS activity were affected by administration of DX-9065a and DEGR-F.VIIa. These results suggested that r-TFPI ameliorates LPS-induced hypotension by reducing excessive production of NO in rats given LPS and this effect was not attributable to its anticoagulant effects, but to the inhibition of TNF-alpha production. |
| 2001 | IC14, a CD14 specific monoclonal antibody, is a potential treatment for patients with severe sepsis. | J Endotoxin Res | CD14 is a pattern recognition receptor for the bacterial cell wall components from Gram-positive and Gram-negative bacteria as well as mycobacteria. Binding of lipopolysaccharide (LPS) or other cell wall constituents to CD14 initiates signal transduction through the Toll-like receptors resulting in the release of pro-inflammatory cytokines and the initiation of the systemic inflammatory response. In rabbits and non-human primates, CD14 specific antibodies were shown to attenuate responses to LPS or Escherichia coli challenge including pro-inflammatory cytokine release, acute lung injury, hypotension and changes in lung, liver, spleen and adrenal gland morphology. In healthy human subjects, single doses of a chimeric CD14 antibody (IC14) have been shown to be well tolerated and result in a dose-related degree of saturation of CD14 receptors on monocytes and granulocytes. Pretreatment of healthy subjects with IC14 2 h prior to LPS resulted in an attenuation of the LPS-induced fever, clinical symptoms, and leukocyte activation and degranulation. IC14 inhibited the release of TNF-alpha, IL-6, and IL-10 and delayed the release of sTNFR(I) and IL-1ra. Further studies are in progress to characterize the safety and clinical pharmacology of IC14 in patients with severe sepsis. |
| 2001 | Nuclear factor-kappaB as a target of cyclosporin in acute hypovolemic hemorrhagic shock. | Cardiovasc Res | Cyclosporin is an immunosuppressive drug that blocks Nuclear Factor kappaB (NF-kappaB) activation. We investigated the role of NF-kappaB in acute hypovolemic hemorrhagic (Hem) shock and the effects of cyclosporin in this model of experimental shock.Hem shock was induced in male anesthetized rats by intermittently withdrawing blood from an iliac catheter over a period of 20 min (bleeding period) until mean arterial blood pressure (MAP) fell and stabilized within the range of 20-30 mmHg. Two minutes after bleeding cessation, animals received intravenously cyclosporin (1 mg kg(-1)) or its vehicle. Survival rate and survival time were evaluated for 120 min after bleeding was discontinued. Plasma TNF-alpha levels were investigated at different time points after bleeding cessation. Moreover we investigated levels of TNF-alpha mRNA in the liver, vascular reactivity, liver NF-kappaB binding activity and levels of the inhibitory protein IkappaBalpha in the cytoplasm.Hemorrhagic shocked rats died in 27+/-6 min following the cessation of bleeding, experienced a marked hypotension (mean arterial blood pressure=20-30 mmHg) and had enhanced plasma levels of Tumor Necrosis Factor-alpha (208+/-22 pg ml(-1), 20 min after the end of bleeding). Furthermore, aortas taken 20 min after bleeding from hemorrhagic shocked rats showed a marked hypo-reactivity to phenylephrine (PE: 1 nM-10 microM) compared with aortas harvested from sham shocked rats. Hem shocked rats also had increased levels of TNF-alpha mRNA in the liver (15-20 min after the end of bleeding). Electrophoretic mobility shift assay showed that liver NF-kappaB binding activity increased in the nucleus 10 min after the end of hemorrhage and remained elevated until the death of animals. Western blot analysis suggested that the levels of inhibitory protein IkappaBalpha in the cytoplasm decreased at 5 min after the end of bleeding. Cyclosporin inhibited the loss of IkappaBalpha protein from the cytoplasm and prevented NF-kappaB binding activity in the nucleus. Furthermore, cyclosporin increased survival time (118+/-7 min; P<0.01) and survival rate (vehicle=0% and cyclosporin=80%, at 120 min after the end of bleeding), reverted the marked hypotension, decreased liver mRNA for TNF-alpha, reduced plasma TNF-alpha (28+/-7 pg ml(-1)), and restored to control values the hypo-reactivity to PE.Our results suggest that acute blood loss (50% of the estimated total blood volume over a period of 20 min) causes early activation of NF-kappaB which triggers an inflammatory cascade leading to a fatal outcome. Cyclosporin blocks NF-kappaB activation and protects against hypovolemic hemorrhagic shock. |
| 2001 | Activated protein C prevents endotoxin-induced hypotension in rats by inhibiting excessive production of nitric oxide. | Circulation | Excessive production of nitric oxide (NO) by the inducible isoform of NO synthase (iNOS) is critically involved in endotoxin (ET)-induced hypotension. Tumor necrosis factor-alpha (TNF-alpha) plays an important role in induction of iNOS. Because activated protein C (APC), a physiological anticoagulant, inhibits TNF-alpha production, it might prevent hypotension by inhibiting excessive production of NO. In this study, we examined this possibility using a rat model of septic shock.Intravenous administration of APC prevented both ET-induced hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-). The hypotension was also inhibited when APC was administered 30 minutes after ET administration. APC inhibited the increases in lung levels of iNOS activity by inhibiting expression of iNOS mRNA in animals given ET. APC significantly inhibited the increases in lung tissue levels of TNF-alpha and expression of TNF-alpha mRNA in animals given ET. Neither DEGR-F.Xa, a selective inhibitor of thrombin generation, nor DIP-APC, an active site-blocked APC, showed any effect on these ET-induced changes. Both inhibition of TNF-alpha production by leukocytopenia and treatment with anti-rat TNF-alpha antibody produced effects similar to those induced by APC. Aminoguanidine, a selective inhibitor of iNOS, inhibited both the hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-) in this animal model.These observations strongly suggest that APC inhibits iNOS induction by decreasing TNF-alpha production, leading to the prevention of ET-induced hypotension. Furthermore, such effects of APC were not dependent on its anticoagulant effects but rather on its serine protease activity. |
| 2001 | Endotoxemic renal failure in mice: Role of tumor necrosis factor independent of inducible nitric oxide synthase. | Kidney Int | Renal failure is a frequent complication of sepsis with a high mortality. Tumor necrosis factor (TNF) has been suggested to be a factor in the acute renal failure in sepsis or endotoxemia. Recent studies also suggest involvement of nitric oxide (NO), generated by inducible NO synthase (iNOS), in the pathogenesis of endotoxin-induced renal failure. The present study tested the hypothesis that the role of TNF in endotoxic renal failure is mediated by iNOS-derived NO.Renal function was evaluated in endotoxemic [Escherichia coli lipopolysaccharide (LPS), 5 mg/kg IP] wild-type and iNOS knockout mice. The effect of TNF neutralization on renal function during endotoxemia in mice was assessed by a TNF-soluble receptor (TNFsRp55).An injection of LPS to wild-type mice resulted in a 70% decrease in glomerular filtration rate (GFR) and in a 40% reduction in renal plasma flow (RPF) 16 hours after the injection. The results occurred independent of hypotension, morphological changes, apoptosis, and leukocyte accumulation. In mice pretreated with TNFsRp55, only a 30% decrease in GFR without a significant change in RPF in response to LPS, as compared with vehicle-treated mice, was observed. Also, the serum NO concentration was significantly lower in endotoxemic wild-type mice pretreated with TNFsRp55, as compared with untreated endotoxemic wild-type mice (260 +/- 52 vs. 673 +/- 112 micromol/L, P < 0.01). In LPS-injected iNOS knockout mice and wild-type mice treated with a selective iNOS inhibitor, 1400W, the development of renal failure was similar to that in wild-type mice. As in wild-type mice, TNFsRp55 significantly attenuated the decrease in GFR (a 33% decline, as compared with 75% without TNFsRp55) without a significant change in RPF in iNOS knockout mice given LPS.These results demonstrate a role of TNF in the early renal dysfunction (16 h) in a septic mouse model independent of iNOS, hypotension, apoptosis, leukocyte accumulation, and morphological alterations, thus suggesting renal hypoperfusion secondary to an imbalance between, as yet to be defined, renal vasoconstrictors and vasodilators. |
| 2001 | Oxidative stress causes nuclear factor-kappaB activation in acute hypovolemic hemorrhagic shock. | Free Radic Biol Med | Nuclear Factor kappaB (NFkappaB) is an ubiquitous rapid response transcription factor involved in inflammatory reactions and exerts its action by expressing cytokines, chemokines, and cell adhesion molecules. We investigated the role of NF-kappaB in acute hypovolemic hemorrhagic (Hem) shock. Hem shock was induced in male anesthetized rats by intermittently withdrawing blood from an iliac catheter over a period of 20 min (bleeding period) until mean arterial blood pressure (MAP) fell and stabilized within the range of 20-30 mmHg. Hemorrhagic shocked rats died in 26.3 +/- 2.1 min following the discontinuance of bleeding, experienced a marked hypotension (mean arterial blood pressure = 20-30 mmHg) and had enhanced plasma levels of Tumor Necrosis Factor-alpha (200 +/- 15 pg/ml, 20 min after the end of bleeding). Furthermore, aortas taken 20 min after bleeding from hemorrhagic shocked rats showed a marked hypo-reactivity to phenylephrine (PE; 1nM to 10 microM) compared with aortas harvested from sham shocked rats. Hem shocked rats also had increased levels of TNF-alpha mRNA in the liver (15-20 min after the end of bleeding) and enhanced plasma levels of 2,5-dihydroxybenzoic acid (2,5-DHBA; 6 +/- 2.2 microm), 2,3-dihydroxybenzoic acid (2,3-DHBA; 13 +/- 2.1 microm), both studied to evaluate OH(*) production. Electrophoretic mobility shift assay showed that liver NF-kappaB binding activity increased in the nucleus 10 min after the end of hemorrhage and remained elevated until the death of animals. Western blot analysis suggested that the levels of inhibitory IkappaBalpha protein in the cytoplasm became decreased at 5 min after the end of bleeding. IRFI-042, a vitamin E analogue (20 mg/kg intraperitoneally 2 min after the end of bleeding), inhibited the loss of IkappaBalpha protein from the cytoplasm and blunted the increase in NF-kappaB binding activity. Furthermore IRFI-042 increased survival time (117.8 +/- 6.51 min; p <.01) and survival rate (vehicle = 0% and IRFI-042 = 80%, at 120 min after the end of bleeding), reverted the marked hypotension, decreased liver mRNA for TNF-alpha, reduced plasma TNF-alpha (21 +/- 4.3 pg/ml), and restored to control values the hypo-reactivity to PE. Our results suggest that acute blood loss (50% of the estimated total blood volume over a period of 20 min) causes early activation of NF-kappaB, likely through an increased production of reactive oxygen species. This experiment indicates that NF-kappaB-triggered inflammatory cascade becomes early activated during acute hemorrhage even in the absence of resuscitation procedures. |
| 2001 | The influence of phosphodiesterase inhibitor, rolipram, on hemodynamics in lipopolysaccharide-treated rats. | Jpn J Pharmacol | Administration of bacterial endotoxin (lipopolysaccharide, LPS) intravenously has been noted to produce a shock state, which is characterized by hypotension and multi-organ system failure. The aim of the present investigation was to (a) examine the influence of rolipram on hemodynamics, plasma levels of tumor necrosis factor-alpha (TNF-alpha) levels, and production of inducible nitric oxide synthase (iNOS) in the lungs, ex vivo, in LPS-treated rats, and (b) determine the cardiovascular effects of a selective alpha1-adrenoceptor agonist, methoxamine, in the absence or presence of rolipram in rats treated with LPS. Blood pressure, cardiac index, heart rate and arterial resistance were assessed in Long-Evans rats anesthetized with thiobutabarbital. Administration of LPS to animals resulted in a significant reduction in cardiac index over time. The administration of LPS to rats resulted in a substantial rise in the plasma levels of TNF-alpha. Furthermore, the injection of LPS resulted in a significant increase in the iNOS activity in the lungs. Pre-treatment with rolipram prevented the decline in cardiac index in animals that received LPS. Infusion of methoxamine into animals injected with rolipram and pre-treated with LPS did not result in significant changes in cardiac index. Pre-treatment with rolipram or dexamethasone in animals injected with LPS significantly prevented the rise in TNF-alpha when compared to the respective values in vehicle-treated animals. Our present observations support the view that the cardiac index can be maintained in animals treated with LPS independent of iNOS inhibition. |
| 2001 | Phase II trial of systemic recombinant interleukin-2 in the treatment of refractory nasopharyngeal carcinoma. | Oncology | Interleukin-2 (IL-2) is a cytokine produced by activated T cells, which has shown powerful immunostimulatory and antineoplastic properties. Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus-associated cancer with abundant lymphocyte infiltration histologically. The activity of IL-2 in the treatment of NPC patients is currently unknown. A phase II study was, therefore, initiated to evaluate the efficacy, toxicity and immunological consequences of intravenous bolus IL-2 in patients with recurrent/metastatic NPC.Between November 1996 and April 1997, 14 patients with recurrent/metastatic NPC were entered into the study. Recombinant IL-2 (Proleukin, Chiron) was injected by intravenous bolus every 8 h at 72,000 IU/kg for a maximum of 15 doses. After 7 days, patients were retreated with a second identical cycle of therapy. Those patients who were stable or responding to treatment 5-6 weeks later went on to receive another course (two cycles) of therapy. All patients received prophylactic antibiotics and antipyretic medicine. Response and toxicities were evaluated. Serial plasma level of TNF-alpha, IL-6, soluble IL-2 receptor, IL-10 and soluble CD8 were determined.Fourteen patients received a total of 34 cycles of therapy. No response was observed. Fifty percent had stable disease, 50% had progressive disease after a median of two cycles of therapy. There was one treatment-related death from acute myocardial infarction. Body weight increase (>5%) occurred in 80% of cycles, and hypotension (BP <80 mm Hg systolic) occurred in 53%. Serum creatinine increase (>2 mg%) occurred in 24% of cycles, and SGOT/SGPT increase (>3x) in 10% of cycles. Symptoms of somnolence, general malaise, nausea and vomiting, pruritus, xerostomia, desquamation were generally mild to moderate but rapidly reversible.The single modality of intravenous bolus IL-2 at the dose level of 72,000 IU/kg is clinically ineffective in NPC patients. Potential mechanisms of the ineffectiveness of IL-2 therapy on NPC patients are discussed. |
| 2001 | In vitro modulation of inducible nitric oxide synthase gene expression and nitric oxide synthesis by procalcitonin. | Crit Care Med | Serum procalcitonin (PCT) concentration was recently introduced as valuable diagnostic marker for systemic bacterial infection and sepsis. At present, the cellular sources and biological properties of PCT are unclear. During sepsis and septic shock, inducible nitric oxide synthase (iNOS) gene expression is stimulated followed by the release of large amounts of nitric oxide (NO). We investigated the possible association between PCT and iNOS gene expression in an in vitro cell culture model.Prospective, controlled in vitro cell culture study.University research laboratories.Confluent rat vascular smooth muscle cells (VSMC) were incubated for 24 hrs and 48 hrs with PCT (1 ng/mL, 10 ng/mL, 100 ng/mL, 1,000 ng/mL, 5,000 ng/mL) alone or with the combination of tumor necrosis factor-alpha (TNF-alpha, 500 U/mL) plus interferon-gamma (IFN-gamma, 100 U/mL). iNOS gene expression was measured by qualitative as well as quantitative polymerase chain reaction analysis, NO release was estimated by the modified Griess method.PCT in increasing concentrations had no effect on iNOS gene expression and nitrite/nitrate release for 24 hrs and 48 hrs, respectively. However, PCT ameliorated TNF-alpha/IFN-gamma-induced iNOS gene expression in a dose-dependent manner (maximal inhibition at PCT 100 ng/mL by -66% for 24 hrs and -80% for 48 hrs). This was accompanied by a significantly reduced release of nitrite/nitrate into the cell culture supernatant (maximal reduction at PCT 100 ng/mL by -56% and -45% for 24 hrs and 48 hrs, respectively).We conclude that recombinant PCT inhibits the iNOS-inducing effects of the proinflammatory cytokines TNF-alpha/ IFN-gamma in a dose-dependent manner. This might be a counter-regulatory mechanism directed against the large production of NO and the concomitant systemic hypotension in severe sepsis and septic shock. |
| 2001 | Endothelial protective and antishock effects of a selective estrogen receptor modulator in rats. | Am J Physiol Heart Circ Physiol | This study investigated whether idoxifene, a selective estrogen receptor modulator (SERM), exerted protective effects against ischemia-reperfusion-induced shock. Ovariectomized rats were treated with vehicle, idoxifene, or 17beta-estradiol for 4 days. Rats were subjected to splanchnic artery occlusion (SAO) followed by reperfusion (SOA/R). In vehicle-treated rats, SAO/R resulted in hypotension, hemoconcentration, increased plasma tumor necrosis factor (TNF)-alpha levels, intestinal neutrophil accumulation, and endothelial dysfunction. 17beta-Estradiol treatment increased plasma estradiol concentration and reduced SAO/R-induced tissue injury. Idoxifene treatment had no effect on plasma estradiol concentration but reduced SAO/R-induced hemoconcentration (+8.8 +/- 1.3 vs. +14 +/- 1.3% in the vehicle group, P < 0.01), TNF-alpha production (98 +/- 3.2 vs. 214 +/- 13 pg/ml, P < 0.01), and neutrophil accumulation (0.025 +/- 0.005 vs. 0.047 +/- 0.005 U/g protein, P < 0.01). It also improved endothelial function, prolonged survival time (172 +/- 3.5 vs. 147 +/- 8 min, P < 0.01), and increased survival rate (69 vs. 23%, P < 0.01). Moreover, treatment with 17beta-estradiol or idoxifene in vivo reduced TNF-alpha-induced endothelial dysfunction in vitro. Taken together, these results demonstrated that idoxifene exerted estrogen-like, endothelial-protective, and antishock effects in ovariectomized rats, suggesting that SERMs have therapeutic potential in tissue injury resulting from ischemia-reperfusion. |
| 2001 | Flagellin, a novel mediator of Salmonella-induced epithelial activation and systemic inflammation: I kappa B alpha degradation, induction of nitric oxide synthase, induction of proinflammatory mediators, and cardiovascular dysfunction. | J Immunol | Gram-negative sepsis is mediated by the actions of proinflammatory genes induced in response to microbes and their products. We report that flagellin, the monomeric subunit of flagella, is a potent proinflammatory species released by Salmonella. Flagellin (1 microgram/ml) induces IkappaBalpha degradation, NF-kappaB nuclear translocation, and inducible NO synthase expression in cultured intestinal epithelial cells (IEC). Aflagellic Salmonella mutants do not induce NF-kappaB activation or NO production by cultured IEC. Antiserum to flagellin blocks NO production in IEC induced by medium conditioned by a variety of motile Gram-negative enteric pathogens (Escherichia coli, Salmonella muenchen, Serratia marcescens, Proteus mirabilis, and Proteus vulgaris). Flagellin, when injected systemically (approximately 10 microgram/mouse), induces systemic inflammation characterized by the systemic expression of a range of proinflammatory cytokines and chemokines and of inducible NO synthase. At higher doses (approximately 300 microgram/mouse), flagellin induces shock, characterized by hypotension, reduced vascular contractility in mice, and death. The effects of flagellin do not diminish in C3H/HeJ LPS-resistant mice, indicating that the Toll-like receptor-4 receptor is not involved in flagellin's actions. In LPS-resistant mice, i.p. injection of S. dublin flagellin or medium conditioned by wild-type S. dublin induces serum IFN-gamma and TNF-alpha, whereas medium conditioned by aflagellic mutants has no effect. Flagellin can be detected in the blood of rats with septic shock induced by live bacteria at approximately 1 microg/ml. We propose that flagellin released by Gram-negative pathogens may contribute to the inflammatory response by an LPS- and Toll-like receptor-4-independent pathway. |
| 2000 | Effects of the PAF receptor antagonist UK74505 on local and remote reperfusion injuries following ischaemia of the superior mesenteric artery in the rat. | Br J Pharmacol | The effects of the long lasting and potent PAF receptor antagonist UK74505 were assessed on the local and remote injuries following ischaemia and reperfusion (I/R) of the superior mesenteric artery (SMA) in rats. In a severe model of ischaemia (120 min) and reperfusion (120) injury, in addition to the local and remote increases in vascular permeability and neutrophil accumulation, there was significant tissue haemorrhage, blood neutropenia, systemic hypotension and elevated local and systemic TNF-alpha levels. Post-ischaemic treatment with the selectin blocker fucoidin (10 mg kg(-1)) prevented neutrophil accumulation in tissue and, in consequence, all the local and systemic injuries following severe I/R. Treatment with an optimal dose of UK74505 (1 mg kg(-1)) also reversed local and remote neutrophil accumulation, increases in vascular permeability and intestinal haemorrhage. UK74505 partially inhibited blood neutropenia and reperfusion-induced hypotension. Interestingly, both fucoidin and UK74505 prevented the local, but not systemic, increases of TNF-alpha levels following severe I/R injury, demonstrating an important role of migrating cells for the local production of TNF-alpha. However, the results do not support a role for PAF as an intermediate molecule in the production of systemic TNF-alpha. The beneficial effects of UK74505 and other PAF receptor antagonists in models of I/R injury in animals and the safety of UK74505 use in man warrant further investigations of the use of this drug as preventive measure for I/R injury in humans. |
| A new method of antitumor therapy with a high dose of TNF perfusion for unresectable liver tumors. | Anticancer Res | There are primary and secondary malignant liver tumors for which principal treatment is surgical resection. There is no established treatment for unresectable malignant liver tumors, however, and the prognosis for these is quite poor. An effective treatment for malignant liver tumors is thus urgently needed. Recent advances in molecular biology have uncovered the structures and/or functions of many cytokines thought to have a strong relation with the mechanisms of the antitumor effect of biological therapies. Availability of those cytokines in large amounts and homogeneously owing to advances in recombinant technology makes it possible to use them clinically. Among cytokines demonstrating antitumor activities, tumor necrosis factor-alpha (TNF-alpha) is one of the strongest. However, severe toxicity such as hypotension, abnormalities in liver function, leukopenia, chill and thrombus formation makes TNF-alpha difficult to use systemically as an antitumor drug. To enhance cytotoxicity while decreasing the side effects, especially hypotension, we developed a mutein called TNF-SAM2 by protein-engineering. The biological activity of TNF-SAM2 was more beneficial than TNF-alpha for antitumor therapy, since its side effects were milder. In contrast, using the isolated limb perfusion (ILP) method against malignant melanoma and soft tissue sarcoma of the extremities in combination with TNF-alpha and melphalan, a high response rate of 70-100% was observed. These observations led to the re-evaluation of TNF as an antitumor drug. A preliminary clinical trial was done using TNF-alpha combined with the formation of a closed circuit (isolated hepatic perfusion method) targeting the liver and a response rate of over 75% was achieved against malignant liver tumors. To isolate the liver from the systemic circulation, however, required a laparotomy, so that patients were subjected to excessive surgical stress. Isolated hypoxic hepatic perfusion (IHHP) using balloon catheters is a treatment developed to overcome such stress and we are planning to do clinical trials of IHHP with TNF-SAM2 in combination with a chemotherapeutic agent against malignant liver tumor patients. IHHP combined with TNF-SAM2 and a chemotherapeutic agent might be more beneficial in antitumor effects as well as in maintaining good quality of life (QOL) for the patient. |
| 2000 | Protection against TNF-induced lethal shock by soluble guanylate cyclase inhibition requires functional inducible nitric oxide synthase. | Immunity | Hypotension and shock observed in sepsis, SIRS, and tumor necrosis factor (TNF) or cytokine-based cancer treatment are the consequence of excessive nitric oxide (NO) production and subsequent soluble guanylate cyclase (sGC)-mediated vascular smooth muscle relaxation. We demonstrate here that, while NO synthase (NOS) inhibitors exacerbated toxicity, inhibitors of sGC activation protected against TNF-induced lethality, bradycardia, and hypotension. Importantly, sGC inhibition did not interfere with the antitumor activity of TNF. Using NOS inhibitors or iNOS-deficient animals, we furthermore observed that no protection against TNF toxicity could be obtained in the absence of NO. These data imply that iNOS- (and not eNOS-) derived NO is an endogenous protective molecule indispensable to survive a TNF challenge and exerting this beneficial effect via sGC-independent mechanisms. |
| 2000 | Clinical relevance of cytokine production in hemodialysis. | Kidney Int Suppl | Blood-dialyzer interaction in hemodialysis has the potential to activate mononuclear cells leading to the production of inflammatory cytokines. The extent of activation is dependent on the dialyzer material used and is considered an index of biocompatibility. Cytokines, such as interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and IL-6, may induce an inflammatory state and are believed to play a significant role in dialysis-related morbidity. The interleukin hypothesis suggests that the release of proinflammatory cytokines acts as an underlying pathophysiologic event in hemodialysis-related acute manifestations, such as fever and hypotension. Nevertheless, a cytokine overproduction may alter sleep pattern in chronic hemodialyzed patients, thus explaining the presence of sleep disorders in these patients. A potential role of cytokines in chronic-related morbidity has also been suggested. High levels of some inflammatory cytokines are often associated with anemia caused by hyporesponsiveness to erythropoietin. Cytokine production may also play a relevant role in bone remodeling by regulating osteoblast/osteoclast cell functions and parathyroid hormone (PTH). Finally, cytokine release may have a long-term deleterious effect on mortality of uremic patients by altering immune response and increasing susceptibility to infections. Bioincompatibility of dialytic membranes may also contribute to malnutrition in dialysis patients by increasing the monocyte release of catabolic cytokines such as TNF-alpha and IL-6. Bioincompatible dialytic treatment may induce an inappropriate monocyte activation and cytokine production, which, in turn, may mediate some of the immune and metabolic dysfunction associated with hemodialysis. The use of biocompatible dialytic membranes appears to reduce the monocyte activation and to improve the survival of hemodialysis patients. |
| 2000 | Pretreatment with tumor necrosis factor-alpha attenuates arterial hypotension and mortality induced by endotoxin in pigs. | Crit Care Med | Tumor necrosis factor (TNF)-alpha administration in large amounts can induce a state of shock similar to that seen during severe sepsis. The objective of this study was to determine whether small doses of TNF-alpha might decrease the disposition for the development of shock induced by a subsequent infusion of endotoxin and to determine whether the mechanism of this protective effect of TNF-alpha pretreatment could be associated with up-regulation of the anti-inflammatory cytokine interleukin (IL)-10.Prospective, randomized, experimental study.Investigative intensive care unit at an academic medical center.A total of 14 female Yorkshire pigs, weighing 20-25 kg.We studied two groups of animals-pigs treated with 500 ng/kg recombinant porcine TNF-alpha (n = 7) and pigs given diluent alone (n = 7). At 24 hrs after treatment, both groups of pigs were subjected to a 24-hr continuous infusion of lipopolysaccharide (LPS) at a rate of 80 ng/kg/min.The mortality rate was determined in both groups. Hemodynamic indices, oxygen transport variables, total and differential white cell counts, and serum concentrations of TNF and IL-10 were determined at frequent intervals before and after TNF-alpha administration and during the LPS infusion. Additionally, peripheral blood mononuclear cells were collected for determination of messenger ribonucleic acid expression of IL-10 by reverse transcription-polymerase chain reaction. The administration of TNF-alpha at the dose used in this study did not have any profound effect. No pig treated with TNF-alpha died in response to the LPS infusion. In contrast, three of seven control pigs died during the LPS infusion. Lipopolysaccharide-induced arterial hypotension and arterial hypoxemia were attenuated in the TNF-alpha-treated group. Both groups had significant increases in serum concentrations of TNF-alpha in response to LPS, with no significant difference in peak serum TNF-alpha between groups. Neither serum concentrations of IL-10 nor expression of IL-10 messenger ribonucleic acid in circulating mononuclear cells differed between groups.The administration of TNF-alpha attenuated the severity of hyperdynamic shock induced by a subsequent infusion of endotoxin. This effect could not be associated with increased expression or elaboration of the anti-inflammatory cytokine IL-10. |
| 1998 | Implications of the analogy between recombinant cytokine toxicities and manifestations of hantavirus infections. | Cancer Biother Radiopharm | The etiologic hantavirus of the 1993 emergence of an acute pulmonary failure syndrome in the area around northwestern New Mexico was quickly recognized as related to the Hantaan virus responsible for the outbreak of Korean epidemic hemorrhagic fever (EHF) among UN troops in 1951. Discovery of the new disease which was named the hantavirus pulmonary syndrome (HPS) and its causative agent the Sine Nombre virus (SNV) inspired detailed comparisons between the two disorders. Major damage to the epithelial cells of the capillaries and arterioles throughout the body leading to extensive capillary leak and subsequent hypotension and shock was the common denominator. The lung capillaries and arterioles were the focus of attack that could lead to rapid pulmonary failure in HPS and the corresponding renal and retroperitoneal vessels that caused a more protracted illness in EHF, but both displayed remarkably similar peripheral blood abnormalities including abnormal mononuclear cells, immature neutrophilia, thrombocytopenia, and hemoconcentration characteristic enough to make blood smear examination a useful tool in early diagnosis. There are evidences that a heavy virus presence in the involved endothelial cells is accompanied by various mononuclear cells capable of generating potent immune response in these areas. Relevant toxic effects of systemically-administered high-dose interleukin-2 for resistant cancers include fever, chills, diarrhea, renal dysfunction, capillary leak syndrome accompanied by hypotension requiring aggressive pressor support, and occasional pleural effusions with diffuse pulmonary infiltrates and hypoxia severe enough to require ventilatory assistance. Peripheral blood mononuclear cells cultured in vitro with IL-2 secrete secondary cytokines such as IL-1, TNF-alpha, and interferon-gamma (IFN-gamma). TNF-alpha, implicated in the pathophysiology of septic shock, is capable of inducing adult respiratory distress syndrome (ARDS) in experimental animals and humans. The strong similarity of these effects to the manifestations noted in the hantavirus diseases justifies the conviction that these and other cytokines involved in potent immune responses would constitute the pathogenic toxic substances predicted by perceptive early investigators of EHF. This concept is favored by clear indications that in both diseases active virus infection disappears the first few days and the ages of involvement correlate with periods of immunocompetence. The paradox of systemic injections of IL-2 that risk hantavirus-type toxicities for treating renal cell carcinoma and melanoma might be avoided by giving potentially more efficacious plant mitogens like PHA as previously reported. The expanded disclosure of a collaborator's method suggesting superior potential for cancer cure involves a unique application of pokeweed mitogen that delivers various cellular and cytokine responses directly to the tumor. |
| 2000 | Systemic toxicity and cytokine/acute phase protein levels in patients after isolated limb perfusion with tumor necrosis factor-alpha complicated by high leakage. | Ann Surg Oncol | Since the introduction of high-dose tumor necrosis factor-alpha (TNFalpha) in the setting of isolated limb perfusion (ILP) in the clinic, prevention of leakage to the body of the patient is monitored with great precision for fear of TNF-mediated toxicity. That we observed remarkably little toxicity in patients with and without leakage prompted us to determine patterns of cytokines and acute phase proteins in patients with high leakage and in patients without any leakage.TNFalpha, interleukin (IL)-6, IL-8, C-reactive protein, and secretory (s)-phospholipase A2 were measured at several time points during and after (until 7 days) ILP in 10 patients with a leakage to the systemic circulation varying in percentage from 12% to 65%. As a control, the same measurements, both in peripheral blood and in perfusate, were performed in nine patients without systemic leakage.In patients with systemic leakage, levels of TNFalpha increased during ILP, reaching values to 277 ng/ml. IL-6 and IL-8 peaked 3 hours after ILP with values significantly higher compared with patients without systemic leakage. C-reactive protein and s-phospholipase A2 peaked at day 1 in both patient groups, s-phospholipase A2 with significant higher levels and C-reactive protein, in contrast, with lower levels in the leakage patients.High leakage of TNFalpha to the systemic circulation, caused by a complicated ILP, led to 10-fold to more than 100-fold increased levels of TNFalpha, IL-6, and IL-8 in comparison with patients without leakage. The increase of the acute phase proteins was limited. Even when high leakage occurs, this procedure should not lead to fatal complications. The most prominent clinical toxicity was hypotension (grade III in four patients), which was easily corrected. No pulmonary or renal toxicity was observed in any patient. It is our experience that, even in the rare event of significant leakage during a TNFa-based ILP, postoperative toxicity is usually mild and can be easily managed by the use of fluid and, in some cases, vasopressors. |
| 2000 | Protective effects of cyclosporin-A in splanchnic artery occlusion shock. | Br J Pharmacol | Cyclosporin A (CsA) is an immunosuppressant drug that inhibits nitric oxide (NO) synthase induction in vascular smooth muscle cells. Splanchnic artery occlusion (SAO) shock is a lethal type of shock characterized by a marked vascular dysfunction in which the L-arginine/nitric oxide pathway plays an important role. We investigated whether CsA exerts protective effects in SAO shock by interfering with the L-arginine/nitric oxide pathway. Male anaesthetized rats (n=156) were subjected to clamping of the splanchnic arteries for 45 min. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham operated animals were used as controls. SAO shocked rats had a decreased survival (86+/-6 min, while sham shocked rats survived more than 240 min), marked hypotension, increased serum levels of TNF-alpha, enhanced plasma nitrite/nitrate concentrations (75+/-7.1 microM; sham shocked rats=1.6+/-0.5 microM) and enhanced inducible NO synthase (iNOS) protein induction and activity in the aorta. Moreover aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM - 10 microM). CsA (0.25, 0.5 and 1 mg kg(-1), 5 min after reperfusion) increased survival rate (SAO+CsA=236+/-9 min following the highest dose), reverted the marked hypotension, reduced plasma nitrite/nitrate concentration (11+/-5.2 microM following the highest dose), restored to control values the hyporeactivity to PE, and blunted iNOS protein induction and activity in aortic rings. The present data indicate that in an experimental rat model CsA may have antishock properties related to inhibition of L-arginine/nitric oxide pathway. |
| 2000 | The effect of intensive plasma water exchange by hemofiltration on hemodynamics and soluble mediators in canine endotoxemia. | Am J Respir Crit Care Med | High volume hemofiltration (HVHF) (200 ml/kg/h) improves hemodynamics in experimental septic shock but is difficult to apply clinically. Accordingly, we studied whether less intensive HVHF (80 ml/kg/h) can still improve hemodynamics in experimental septic shock. We also investigated its effect on the serum concentrations of several inflammatory mediators, including endothelin (ET-1), endotoxin (LPS), tumor necrosis factor-alpha (TNF-alpha), and 6-keto prostaglandin F(1alpha) (6-kepto PGF(1alpha)). Sixteen anesthetized dogs were connected to a continuous veno-venous hemofiltration (CVVH) (filtration: 80 ml/kg/h) or sham circuit and endotoxin (0.5 mg/kg) was infused intravenously over 5 min. Hemodynamic variables were measured at baseline and at 15, 45, 90, and 180 min. The major hemodynamic finding was that endotoxin-induced hypotension was significantly attenuated by intensive CVVH (p < 0.04). Changes in cardiac output and right ventricular ejection fraction were equal in both groups. ET-1 levels, but not LPS, TNF-alpha, or 6-keto PGF(1alpha), were lower during CVVH (p = 0.042). Endotoxin or TNF-alpha were not found in the ultrafiltrate. Median clearances of ET-1 and 6-keto PGF(1alpha) during intensive CVVH were 8.8 and 25.9 ml/m, respectively. We conclude that intensive CVVH attenuates the early component of endotoxin-induced hypotension and reduces serum concentrations of endothelin-1. The effect of CVVH on blood pressure is not explained by convective clearance of the mediators in question. |
| 1999 | Comparison between effects of dantrolene and nifedipine on lipopolysaccharide-induced endotoxemia in the anesthetized rats. | Chin J Physiol | Intracellular calcium is an important mediator for regulating the cellular response in endotoxemia. In this study, we investigated the effects of dantrolene and nifedipine, two agents of reducing intracellular calcium levels, on bacterial endotoxin (lipopolysaccharide, LPS; 10 mg/kg i.v.)-induced production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) as well as hemodynamic changes in the anesthetized rat. Injection of LPS (i) induced biphasic changes of blood glucose and rectal temperature: an initial increased phase (<180 min after injection of LPS) followed by a decreased phase (at 240 or 360 min), (ii) caused a significant fall in mean arterial blood pressure from 119+/-3 mmHg (at time 0) to 73+/-67 mmHg (at 360 min) with a concomitant increase of heart rate, (iii) resulted in a substantial hyporeactivity to norepinephrine (NE) (1 microg/kg i.v.), (iv) increased plasma nitrate (an indicator of NO formation) in a time-dependent manner, and (v) induced bell-shape changes in plasma TNF-alpha levels which reached a peak at 60 min. Pretreatment of animals with dantrolene (1 mg/kg i.v. at 20 min prior to LPS) or nifedipine (20 microg/kg i.v. infusion for 20 min at 20 min prior to LPS) not only attenuated the delayed circulatory failure (e.g. delayed hypotension and vascular hyporeactivity to NE), but also prevented the overproduction of NO caused by LPS in the rat. However, the prevention of NO overproduction by dantrolene, but not by nifedipine, was associated with an inhibition of TNF-alpha production elicited by LPS. Thus, both dantrolene and nifedipine have beneficial hemodynamic effects, although through different mechanisms, in animals with endotoxic shock. |
| 2000 | Increased plasma adrenomedullin levels in hemodialysis patients with sustained hypotension. | Kidney Int | Sustained hypotension in end-stage renal disease patients is characterized, despite an overactivation of the sympathetic and renin-angiotensin systems, by decreased vascular resistance and a blunted vascular response to pressor stimuli. An increased production of one or more vasodilator substances might play a role in the reduced vascular resistance and response to pressor stimuli in these patients. We evaluated the possible role of an increased production of nitric oxide and/or adrenomedullin (ADM) in the pathophysiology of chronic hypotension in hemodialysis (HD) patients.Three groups of hypotensive (N = 9), normotensive (N = 10), and hypertensive (N = 9) HD patients were included in the study. Plasma renin activity (PRA) and plasma levels of catecholamines, ADM, nitrite/nitrate (an estimator of nitric oxide production), tumor necrosis factor (TNF), and interleukin-1beta (IL-1beta) were measured. Plasma volume and left ventricular ejection fraction (LVEF) were also evaluated.Plasma levels of nitrite/nitrate and ADM were elevated in HD patients with respect to the reference values in normal subjects. Plasma ADM levels, but not nitrite/nitrate levels, were higher in hypotensive (368.1 +/- 25.4 pg/mL) than normotensive (225 +/- 9.9 pg/mL) and hypertensive HD patients (278.2 +/- 15.5 pg/mL, P < 0.01). When considering hypotensive and normotensive patients together, the mean blood pressure inversely correlated with time on HD (r = -0. 53, P < 0.05) and plasma ADM levels (r = -0.78, P < 0.01).Plasma ADM and nitrite/nitrate levels are increased in HD patients, but only ADM levels were higher in hypotensive than in normotensive and hypertensive HD patients. The higher plasma levels of this peptide in hypotensive patients and its inverse correlation with mean arterial pressure suggest that ADM may be involved in the pathophysiology of chronic hypotension in HD patients. |
| 2000 | Endogenous mediators in emergency department patients with presumed sepsis: are levels associated with progression to severe sepsis and death? | Ann Emerg Med | We sought to determine whether levels of the endogenous mediators tumor necrosis factor (TNF)-alpha, interleukin (IL) 6, and nitric oxide (NO) measured in patients with presumed sepsis (systemic inflammatory response syndrome [SIRS] and infection) are different than levels in patients with presumed noninfectious SIRS, whether levels are associated with septic complications, and whether there are potential relationships between mediators.A prospective, observational tricenter study of a convenience sample of adults presenting to the emergency department meeting Bone's criteria for SIRS (any combination of fever or hypothermia, tachycardia, tachypnea, or WBC count aberration) was performed. Mediator levels were determined and associated with deterioration to severe sepsis (hypotension, hypoperfusion, or organ dysfunction) and death in subjects admitted to the hospital with presumed sepsis.One hundred eighty subjects with SIRS were enrolled and classified into 3 groups: group 1 (SIRS, presumed infection, admitted; n=108), group 2 (SIRS, presumed infection, discharged; n=27), and group 3 (SIRS, presumed noninfectious, admitted; n=45). Group 1 TNF-alpha and IL-6 levels were significantly higher than those found in the other groups. NO levels for groups 1 and 2 were significantly lower than those for group 3. TNF-alpha and IL-6 levels were higher in the group 1 subjects who had bacteremia or progressed to severe sepsis or death. NO levels were not associated with these outcomes.ED patients admitted with presumed sepsis have elevated cytokine levels compared with patients with sepsis who are discharged and with those patients with presumed noninfectious SIRS. An association appears to exist between cytokines and subsequent septic complications in these patients. The importance of these measures as clinical predictors for the presence of infection and subsequent septic complications needs to be evaluated. |
| 1999 | Heart function after severe hemorrhagic shock. | Shock | Test whether brief deep hemorrhagic hypotension or prolonged moderate hemorrhagic hypotension impairs intrinsic heart function.Pentobarbital-anesthetized, non-anticoagulated rats were cannulated via the carotid artery. This study focuses on three main groups: 1) hemorrhage to a mean arterial blood pressure (MAP)=25 mm Hg for 1 h (1 h severe shock), 2) hemorrhage to MAP=40 mm Hg for 3 h (3 h moderate shock), 3) no hemorrhage (control). Hearts were either freeze-clamped in-situ for tissue analysis (n=6 per group) or were removed to study in vitro cardiac function and efficiency using a working heart perfusion (n=12 per group, glucose (11 mM)/palmitate (0.4 mM), 3% BSA buffer). Following perfusion, hearts were freeze-clamped and analyzed for free CoA, acetyl-, succinyl-, and malonyl-CoA, ATP content and for TNF-alpha content.Isolated working hearts obtained following 1 h of severe shock generated 20% less hydraulic work than hearts obtained from control rats or rats subjected to 3 h of moderate shock. The cardiac efficiency (work/O2 consumption) was also significantly reduced with 1 h severe shock (0.76 +/- 0.07 after 15 min perfusion) versus control (0.96 +/- 0.06) or 3 h prolonged shock (1.10 +/- 0.09). Myocardial Co-A ester, ATP and TNF-alpha concentrations were not different between control and shocked hearts, although TNF-alpha concentrations increased significantly in all hearts during ex vivo perfusion.Depth of hypotension is more important than duration in causing intrinsic cardiac dysfunction. This post-hemorrhagic cardiac dysfunction is not a result of substrate limitation to the heart, nor myocardial TNF-alpha accumulation, but is more likely a result of impaired transfer of energy from molecular oxygen into external cardiac work. |
| 1999 | Attenuation of catecholamine-induced immunosuppression in whole blood from patients with sepsis. | Shock | Studies performed on healthy volunteers have revealed that catecholamines down-regulate the lipopolysaccharide (LPS)-induced production of tumor necrosis factor (TNF)alpha, interleukin (IL)-6, and IL-1beta. We extended this observation and show that this effect is based on changes in the mRNA concentration of these cytokines. Catecholamines are increased in severe sepsis due to endogenous production and have to be administered exogenously when the disease has proceeded to the state of prolonged hypotension. We here investigated whether the immunomodulating effect of catecholamines could also be demonstrated in the blood of patients with prolonged severe sepsis and of those in prolonged septic shock. Blood was stimulated ex vivo with LPS in the presence and absence of epinephrine and the cytokine protein concentration was determined. In blood of healthy volunteers, epinephrine reduced the LPS-stimulated synthesis of TNFalpha by 62.5% (P< 0.0001), of IL-6 by 39% (P< 0.0001), and of IL-1beta by 40% (P= 0.015), and increased the LPS-stimulated IL-10 production by 77.8% (P < 0.0001). Correspondingly, in blood of patients with prolonged severe sepsis, TNFalpha was reduced by 67.2% (P < 0.0001) and IL-6 was reduced by 32.9% (P < 0.0001); IL-1beta and IL-10 were not modulated by catecholamines in these patients. In blood samples of patients in prolonged septic shock, epinephrine did not modulate cytokine levels of IL-6 and IL-10, and decreased TNFalpha only by 36.4% (P < 0.0001). Interestingly, epinephrine suppressed the IL-1beta production by 73% (P < 0.0001) in blood of patients in prolonged septic shock, which was twice as much as in blood samples of healthy volunteers. The altered response of septic blood to catecholamines might be due to an altered reactivity of leukocytes in the prolonged disease although an additional role of preexisting catecholamines cannot be completely excluded. |
| 1999 | Platelet-activating factor and arachidonic acid metabolites mediate tumor necrosis factor and eicosanoid kinetics and cardiopulmonary dysfunction during bacteremic shock. | Crit Care Med | Platelet-activating factor (PAF) and eicosanoids are putative mediators of septic shock that are associated with release of tumor necrosis factor (TNF). The purpose of this investigation was to a) examine temporal patterns of TNF and arachidonic acid metabolite release in a porcine model of bacteremic shock and b) selectively block PAF, thromboxane A2, prostacyclin, and leukotrienes to determine the relationships among these inflammatory response mediators and the alterations in cardiorespiratory dysfunction for which they are required.Prospective, nonrandomized, controlled trial.Laboratory at a university medical center.Thirty-four female Yorkshire swine.Animals were divided into six experimental groups: five septic groups receiving an infusion of Aeromonas hydrophila at 0.2 mL/kg/hr, gradually increasing to 0.4 mL/kg/hr over 4 hrs. Each of four septic groups was pretreated with a specific mediator inhibitor (PAF receptor antagonist, n = 6; prostacyclin antibody, n = 5; leukotriene synthesis inhibitor, n = 5; and thromboxane receptor antagonist, n = 6). One septic group (n = 6) received no mediator inhibitor and served as a septic control, and one anesthesia control group (n = 6) received no intervention.PAF receptor blockade significantly increased systemic hypotension and mixed venous oxygen saturation and decreased pulmonary artery pressure, oxygen extraction and consumption, hemoconcentration, and levels of TNF and eicosanoids. Leukotriene inhibition increased mean arterial pressure, pulmonary and systemic vascular resistance indices, and arterial and mixed venous oxygen saturation and reduced pulmonary hypertension, oxygen delivery, oxygen extraction, oxygen consumption, and all measured mediators. Thromboxane receptor blockade lowered TNF and leukotriene levels, ameliorated systemic and pulmonary vasoconstriction, and significantly increased arterial and tissue oxygenation compared with septic controls. Prostacyclin antagonism reduced prostacyclin plasma concentrations, arterial hypoxemia, and oxygen consumption during sepsis and increased circulating leukotriene B4.Elevations in plasma TNF predictably precede peak levels of eicosanoids in this model. PAF, leukotrienes, and thromboxane A2 are necessary for pulmonary hypertension during bacteremia. Systemic hypotension and increased vascular permeability are mediated by both leukotrienes and PAF. There are complex interactions among mediators during sepsis and further studies are required to define these relationships. |
| 1999 | [Shock and its mediators]. | Nihon Geka Gakkai Zasshi | Shock is a biological response associated with hypotension and signs of altered tissue perfusion. Shock can be induced by many different mechanisms. Shock itself induces cytokine production as a result of disturbed microcirculation or ischemia-reperfusion injury. Alternatively, severe inflammatory conditions, such as sepsis and severe acute pancreatitis, are usually associated with prominent mediator production, which often leads to shock. TNF-alpha and IL-1 beta increase the vascular permeability, and nitric oxide reduces systemic vascular resistance. In the management of patients who have experienced clinical insult, we must consider the symptoms of systemic inflammatory response syndrome provoked by inflammatory mediators as a warning sign of the development of shock and organ dysfunction. Early withdrawal from SIRS and avoidance of infectious complications (second attack) should be attempted. |
| 1999 | Effect of profound normovolemic hypotension and moderate hypothermia on circulating cytokines and adhesion molecules. | Shock | Hypotension caused by hypovolemic, hemorrhagic shock induces disturbances in the immune system that may contribute to an increased susceptibility to sepsis. The effect of chemically induced hypotension on circulating cytokines and adhesion molecules has not been investigated yet. In 21 patients scheduled for resection of malignant choroidal melanoma of the eye the perioperative serum levels of the cytokines IL-1beta, IL-6, IL-10, TNF-alpha, and the adhesion molecules sE-Selectin and sICAM-1 were investigated. Moderate hypothermia of 32 degrees C was induced in all patients. In 14 patients profound hypotension (mean arterial blood pressure 35-40 mmHg, hypotension group) was induced by enalapril and nitroglycerin for a mean duration of 71 min. In 7 patients the tumor was not resectable, and hypotension was not induced (controls). We did not detect significant differences in serum levels of cytokines or sE-Selectin perioperatively in patients with profound hypotension compared with controls. In both groups IL-6 serum levels increased significantly and reached a maximum after rewarming (17 +/- 6 and 16 +/- 5 pg/dL, respectively, P < 0.001). IL-1beta, IL-10, and TNF-alpha did not change perioperatively in both groups. On the first postoperative day sICAM-1 serum levels were significantly increased in both groups (mean increase of 96 and 54 ng/mL, respectively, P < 0.01 and P < 0.05). We conclude from this study that profound normovolemic arterial hypotension does not seem to have effects on serum levels of circulating IL-1beta, IL-6, IL-10, TNF-alpha, and sE-Selectin. Perioperative moderate hypothermia may be the reason for the postoperative increase in sICAM-1 levels independent of the blood pressure. |
| 1999 | Tetramethylpyradizine prevents inducible NO synthase expression and improves survival in rodent models of endotoxic shock. | Naunyn Schmiedebergs Arch Pharmacol | This study is to investigate the possible mechanism of beneficial effects of tetramethylpyrazine (TMP) on endotoxic shock which we showed in our preliminary study (Liao et al. 1998; Proc Natl Sci Counc Repub China B 22:46-54). Here, we have confirmed the beneficial effects of TMP on the hypotension, vascular hyporeactivity to noradrenaline (NA), release of tumour necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) in a rat model of circulatory shock induced by bacterial endotoxin (E. coli lipopolysaccharide, LPS). In addition, we further examined the expression of inducible NO synthase in the lung and in the aorta from these rats and evaluated the effect of TMP on the 36-h survival rate in a murine model of endotoxaemia. Male Wistar-Kyoto rats were anaesthetised and instrumented for the measurement of mean arterial pressure (MAP) and heart rate (HR). Injection of LPS (10 mg kg(-1), i.v.) resulted in an acute fall followed by a substantial fall in MAP within 4 h and an increase in HR. In contrast, animals pretreated with TMP (10 mg kg(-1), i.p.; at 30 min prior to LPS) maintained a significantly higher MAP but the tachycardia was further enhanced at 1-2 h when compared to rats given only LPS (LPS rats). The pressor effect of NA (1 microg kg(-1), i.v.) was also significantly reduced after the treatment of rats with LPS. Similarly, the thoracic aorta obtained from rats at 4 h after LPS showed a significant reduction in the contractile responses elicited by NA (1 microM). Pretreatment of LPS rats with TMP partially, but significantly, prevented this LPS-induced hyporeactivity to NA in vivo and ex vivo. The injection of LPS resulted in a bell-shaped change in plasma TNF-alpha level which reached a maximum at 1 h, whereas the effect of LPS on the plasma level of nitrate (an indicator of NO formation) was increased in a time-dependent manner. This increment of both TNF-alpha and nitrate levels was significantly reduced in LPS rats pretreated with TMP. Endotoxaemia for 4 h caused a significantly increased protein expression of iNOS in the lung and the aorta. In LPS rats pretreated with TMP, iNOS protein expression in lung and aorta homogenates was attenuated by 75+/-3% and 57+/-6%, respectively. In addition, the lack of evidence of pressor effect of TMP on rats with endotoxaemia for 4 h suggested that TMP inhibits the induction of iNOS rather than directly inhibiting NOS activity. Treatment of conscious ICR mice with a high dose of endotoxin (60 mg kg(-1), i.p.) resulted in a survival rate of only 15% at 36 h (n=20). However, therapeutic application of TMP (10 mg kg(-1), i.p.; at 0, 6, 15 and 24 h after LPS) increased the 36 h survival rate to 55% (n=20). Thus, TMP inhibits the expression of iNOS and mitigates the delayed circulatory failure caused by endotoxic shock in the rat. In addition, TMP also improves survival in a murine model of severe endotoxaemia. |
| 1999 | Adrenocorticotropin reverses vascular dysfunction and protects against splanchnic artery occlusion shock. | Br J Pharmacol | 1. Tumour necrosis factor (TNF-alpha) is involved in the pathogenesis of splanchnic artery occlusion (SAO) shock. On the other hand, inhibition of TNF-alpha is an important component of the mechanism of action of melanocortins in reversing haemorrhagic shock. We therefore investigated the effects of the melanocortin peptide ACTH-(1 - 24) (adrenocorticotropin fragment 1 - 24) on the vascular failure induced by SAO shock. 2. SAO-shocked rats had a decreased survival rate (0% at 4 h of reperfusion, while sham-shocked rats survived for more than 4 h), enhanced serum TNF-alpha concentrations (755+/-81 U ml-1), decreased mean arterial blood pressure, leukopenia, and increased ileal leukocyte accumulation, as revealed by means of myeloperoxidase activity (MPO=9.4+/-1 U g-1 tissue). Moreover, aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM - 10 microM) (Emax and ED50 in shocked rats=7.16 mN mg-1 tissue and 120 nM, respectively; Emax and ED50 in sham-shocked rats=16.31 mN mg-1 tissue and 100 nM, respectively), reduced responsiveness to acetylcholine (ACh, 10 nM-10 microM) (Emax and ED50 in shocked rats=30% relaxation and 520 nM, respectively; Emax and ED50 in sham-shocked rats=82% relaxation and 510 nM, respectively) and increased staining for intercellular adhesion molecule-1 (ICAM-1). 3. ACTH-(1 - 24) [160 microg kg-1 intravenously (i.v.), 5 min after SAO] increased survival rate [SAO+ACTH-(1 - 24)=80% at 4 h of reperfusion], reversed hypotension, reduced serum TNF-alpha (55+/-13 U ml-1), ameliorated leukopenia, reduced ileal MPO (1.2+/-0.2 U g-1 tissue), restored the reactivity to PE, improved the responsiveness to ACh and blunted the enhanced immunostaining for ICAM-1 in the aorta. 4. Adrenalectomy only in part - but not significantly - reduced the ACTH-induced shock reversal, the survival rate of SAO+ACTH-(1 - 24) adrenalectomized rats being 60% at 4 h of reperfusion; and methylprednisolone (80 mg-1 i.v., 5 min after SAO) had a non-significant effect (10% survival) at 4 h of reperfusion. 5. The present data show that melanocortins are effective also in SAO shock, their effect being, at least in part, mediated by reduced production of TNF-alpha. Furthermore, they demonstrate, for the first time, that this inhibition is responsible for the adrenocorticotropin-induced reversal of vascular failure and leukocyte accumulation. |
| 1999 | Cytokine-release syndrome in patients with B-cell chronic lymphocytic leukemia and high lymphocyte counts after treatment with an anti-CD20 monoclonal antibody (rituximab, IDEC-C2B8). | Blood | Eleven patients with relapsed fludarabine-resistant B-cell chronic lymphocytic leukemia (CLL) or leukemic variants of low-grade B-cell non-Hodgkin's lymphoma (NHL) were treated with the chimeric monoclonal anti-CD20 antibody rituximab (IDEC-C2B8). Peripheral lymphocyte counts at baseline varied from 0.2 to 294.3 x 10(9)/L. During the first rituximab infusion, patients with lymphocyte counts exceeding 50.0 x 10(9)/L experienced a severe cytokine-release syndrome. Ninety minutes after onset of the infusion, serum levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) peaked in all patients. Elevated cytokine levels during treatment were associated with clinical symptoms, including fever, chills, nausea, vomiting, hypotension, and dyspnea. Lymphocyte and platelet counts dropped to 50% to 75% of baseline values within 12 hours after the onset of the infusion. Simultaneously, there was a 5-fold to 10-fold increase of liver enzymes, d-dimers, and lactate dehydrogenase (LDH), as well as a prolongation of the prothrombin time. Frequency and severity of first-dose adverse events were dependent on the number of circulating tumor cells at baseline: patients with lymphocyte counts greater than 50.0 x 10(9)/L experienced significantly more adverse events of National Cancer Institute (NCI) grade III/IV toxicity than patients with less than 50.0 x 10(9)/L peripheral tumor cells (P = .0017). Due to massive side effects in the first patient treated with 375 mg/m(2) in 1 day, a fractionated dosing schedule was used in all subsequent patients with application of 50 mg rituximab on day 1, 150 mg on day 2, and the rest of the 375 mg/m(2) dose on day 3. While the patient with the leukemic variant of the mantle-cell NHL achieved a complete remission (9 months+) after treatment with 4 x 375 mg/m(2) rituximab, efficacy in patients with relapsed fludarabine-resistant B-CLL was poor: 1 partial remission, 7 cases of stable disease, and 1 progressive disease were observed in 9 evaluable patients with CLL. On the basis of these data, different infusion schedules and/or combination regimens with chemotherapeutic drugs to reduce tumor burden before treatment with rituximab will have to be evaluated. |
| 1999 | Interleukin-1 mediates hemodynamic dysfunction and release of eicosanoids and tumor necrosis factor during graded bacteremia. | Shock | The pathophysiologic events of sepsis mediated by interleukin-1 (IL-1) remain ill-defined. The purpose of this study was to identify the circulatory derangements of which IL-1 was a necessary mediator and evaluate its interactions with tumor necrosis factor (TNF) and the eicosanoids during graded bacteremia. Eleven adult female swine were anesthetized, mechanically ventilated, and monitored with pulmonary artery catheters and arterial lines; they received intravenously either saline vehicle (septic control, n = 6) or human recombinant IL-1 receptor antagonist (IL-1ra, n = 5). The animals were then infused with Aeromonas hydrophila (10(9)/mL) for 4 h at rates gradually increased from .2 mL/kg/h to 4 mL/kg/h over 3 h, then sacrificed after 4 h. Mean arterial pressure (MAP), left ventricular stroke work index (LVSWI), and systemic vascular resistance index (SVRI) were recorded at baseline and hourly thereafter, and plasma 6-keto-PGF1alpha (6-KETO), tumor necrosis factor-alpha (TNF) and leukotrienes B4(LTB4) and C4D4E4 (LTCDE), pg/mL, were measured by ELISA. MAP, LVSWI, arterial P(O2) all decreased in the septic control group to levels significantly below those of the IL-1 antagonist animals. Circulating 6-KETO, LTCDE, and TNF increased significantly in all septic animals. Plasma LTB, and TNF were reduced by IL-1 blockade, compared with septic controls. TxB2 was not affected by IL-1 inhibition. There were no intergroup differences in platelet aggregation, but the in vitro aggregation response decreased from baseline in septic controls to 54+/-27% (p < .05). IL-1 is necessary to the development of systemic hypotension impaired LVSWI, and increased intravascular platelet aggregation during graded bacteremia. Conversely, IL-1 helps to maintain stroke volume and low SVRI in graded bacteremia, possibly through increased prostacyclin release. It may contribute to impaired pulmonary gas exchange and increased tissue oxygen demands. TNF release is stimulated in the presence of unopposed IL-1 and may be synergistic with it in the adverse hemodynamic effects of endogenous IL-1. IL-1 is required for increased leukotriene and prostacyclin levels in this model, but it is not involved in thromboxane release. Whether the lack of survival benefit from IL-1ra in human sepsis is due to these mixed cardiopulmonary and mediator effects, to species differences, or to timing of IL-1ra administration is not clear from the data. |
| 1999 | Pentoxifylline improves circulatory failure and survival in murine models of endotoxaemia. | Eur J Pharmacol | Pentoxifylline, a methylxanthine derivative, has been widely used to improve erythrocyte deformability and capillary blood circulation in patients with claudication and cerebrovascular disorders as well as in animals with sepsis. Here, we investigate the effects of pentoxifylline on the hypotension, vascular hyporeactivity to noradrenaline, release of tumour necrosis factor-alpha (TNF-alpha) and nitric oxide (NO), and inducible NO synthase protein expression in a rat model of circulatory shock induced by bacterial endotoxin (Escherichia coli lipopolysaccharide). In addition, we have evaluated the effect of pentoxifylline on the 36-h survival rate in a murine model of endotoxaemia. Male Wistar-Kyoto rats were anaesthetised and instrumented for the measurement of mean arterial pressure and heart rate. Injection of lipopolysaccharide (10 mg/kg, i.v.) resulted in a significant fall in mean arterial pressure and an increase of heart rate. In contrast, animals pretreated with pentoxifylline (3 mg/kg, i.v., at 30 min prior to lipopolysaccharide) maintained a significantly higher mean arterial pressure but showed no effect on the tachycardia when compared to rats given only lipopolysaccharide (lipopolysaccharide-rats). The pressor effect of noradrenaline (1 microg/kg, i.v.) was also significantly reduced after the treatment of rats with lipopolysaccharide. Similarly, rings of thoracic aorta obtained from lipopolysaccharide-rats showed a significant reduction in the contractile responses elicited by noradrenaline (1 microM). Pretreatment of lipopolysaccharide-rats with pentoxifylline partially, but significantly, prevented this lipopolysaccharide-induced hyporeactivity to noradrenaline in vivo and ex vivo. The injection of lipopolysaccharide resulted in bell-shape changes in plasma TNF-alpha level which reached a peak at 60 min, whereas the effect of lipopolysaccharide on the plasma level of nitrate (an indicator of NO formation) was increased in a time-dependent manner. This increase of both TNF-alpha and nitrate levels induced by lipopolysaccharide was significantly reduced in lipopolysaccharide-rats pretreated with pentoxifylline. Endotoxaemia for 240 min caused a significantly increased protein expression of inducible NO synthase in the lung. In lipopolysaccharide-rats pretreated with pentoxifylline, inducible NO synthase protein expression in lung homogenates was attenuated by 48 +/- 5%. Treatment of conscious mice with a high dose of endotoxin (60 mg/kg, i.p.) resulted in a survival rate of only 10% at 36 h (n = 20). However, therapeutic application of pentoxifylline (3 mg/kg, i.p. at 0, 6, 15 and 24 h after lipopolysaccharide) increased the 36-h survival to 35% (n = 20). Thus, pentoxifylline protects against circulatory failure and improves survival in rodents with severe endotoxaemia. These effects may be due to inhibition of the release of TNF-alpha and of the induction of inducible NO synthase. |
| 1998 | Pathogenesis of puumala and other hantavirus infections. | Rev Med Virol | Hantaviruses are rodent/insectivore-borne negative-stranded RNA viruses which belong to the Bunyaviridae family. They do not cause any symptomatic disease in their adult carrier rodents, but in humans they are aetiologic agents of haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), both associated with a significant mortality. In cell culture hantaviruses do not cause cytopathic effects and the mechanisms of disease in man are not well understood. Increased capillary permeability is a central phenomenon in the pathogenesis of hantavirus infections. Although the viruses have in vivo a predilection for endothelial cells, it is presumed that inflammatory mediators of the host immune response play a significant role in the capillary leak that may produce abrupt hypotension and shock in severely ill patients. Mediators released by activated macrophages including NO and TNF-alpha are considered important. The pathogenesis of renal failure in HFRS also awaits to be resolved. This review summarises what is known about these phenomena and discusses also the molecular basis of the putative virulence factors of hantaviruses. Finally, the genetic predisposition and HLA association with severe Puumala virus infection will be discussed. Copyright 1998 John Wiley & Sons, Ltd. |
| 1999 | Tacrolimus suppresses tumour necrosis factor-alpha and protects against splanchnic artery occlusion shock. | Br J Pharmacol | 1. Tumour necrosis factor (TNF-alpha) is a pleiotropic cytokine which is deeply involved in the pathogenesis of splanchnic artery occlusion (SAO) shock. Tacrolimus, formerly known as FK506, is a macrolide antibiotic, that blocks the transcription of several proinflammatory cytokines including TNF-alpha. 2. Male anaesthetized rats were subjected to clamping of the splanchnic arteries for 45 min. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham operated animals were used as controls. SAO shocked rats had a decreased survival rate (0% at 4 h of reperfusion, while sham shocked rats survived more than 4 h), enhanced serum TNF-alpha concentrations (415+/-12 U ml(-1)), decreased mean arterial blood pressure (MAP), leukopenia and increased ileal leukocyte accumulation studied by means of myeloperoxidase activity (MPO=7.5+/-0.3 U g(-1) tissue). Moreover aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM - 10 microM), reduced responsiveness to acetylcholine (ACh, 10 nM - 10 microM) and increased staining for intercellular adhesion molecule-1 (ICAM-1). Furthermore increased mRNA for TNF-alpha was observed in peritoneal macrophages of SAO shocked rats. 3. Tacrolimus (100 microg kg(-1), 5 min after splanchnic arteries occlusion) increased survival rate (SAO + Tacrolimus = 100% at 4 h of reperfusion), reverted the marked hypotension, reduced serum TNF-alpha (15+/-3 U ml(-1)), ameliorated leukopenia, reduced ileal MPO (0.9+/-0.01 U g(-1) tissue), restored to control values the hyporeactivity to PE. improved the reduced responsiveness to ACh and blunted the enhanced immunostaining for ICAM-1 in the aorta. Finally tacrolimus suppressed cytokine mRNA levels in peritoneal macrophages. 4. The data suggest that tacrolimus may represent a new therapeutic approach in circulatory shock. |
| 1999 | Absence of severe systemic toxicity after leakage-controlled isolated limb perfusion with tumor necrosis factor-alpha and melphalan. | Ann Surg Oncol | Severe systemic toxicity and hemodynamic changes after isolated limb perfusion (ILP) with tumor necrosis factor-alpha (TNF-alpha) and melphalan, with or without interferon-gamma, have been reported in several series. We studied whether these side effects could be precluded by preventing leakage from the isolated circuit into the systemic circulation.Clinical and pharmacokinetic data for 20 consecutive patients with recurrent melanoma of the limbs who were treated by ILP with TNF-alpha (3-4 mg) and melphalan, with or without interferon-gamma, were studied. Leakage rates and TNF-alpha levels were determined during and after ILP and were correlated with systemic toxicity and hemodynamic changes.Only two patients experienced leaks (2% and 13%) during ILP. For 18 patients without leakage, the mean peak systemic TNF-alpha level was 2.8 ng/ml at 10 minutes after ILP. After leakage, the peak systemic TNF-alpha levels were 31.9 and 88.3 ng/ml at 5 minutes. Toxicity was mild and consisted mainly of fever (n = 17) and nausea/vomiting (n = 19) during the first day after ILP. Some patients developed tachycardia (n = 6), hypotension (n = 3; responding immediately to fluid challenge), a decrease in the WBC count (n = 3; grade I) or thrombocyte count (n = 11; grade I/II, no hemorrhage or therapeutic intervention), or hepatotoxicity [cytolysis (n = 15; 14 grade I/II and 1 grade IV) or hyperbilirubinemia (n = 7; grade I/II, all resolving spontaneously)]. Patients with tachycardia or hepatotoxicity exhibited significantly higher TNF-alpha levels after ILP, compared with other patients.Systemic toxicity after ILP with TNF-alpha is minimal and does not differ from that after ILP with melphalan alone when leakage is adequately controlled. |
| 1999 | Influence of antithrombin III on coagulation and inflammation in porcine septic shock. | Arterioscler Thromb Vasc Biol | The physiological inhibitor of thrombin, antithrombin III (ATIII, Kybernin P) was investigated for its antiinflammatory and anticoagulant effects in a pig model of septic shock. Pigs were infused with a dose of 0.25 microgram. kg-1. h-1 of lipopolysaccharide (LPS) over a period of 3 hours. Animals developed systemic inflammation, disseminated intravascular coagulation (DIC), organ failure and cardiovascular abnormalities, namely pulmonary hypertension and systemic hypotension. Twenty septic pigs were allocated to 2 study groups, treated either with ATIII (n=10) or placebo (n=10). ATIII was administered as a 250-U/kg IV bolus infusion for 30 minutes (-60 to -30 minutes) followed by a single IV bolus of 125 U/kg (t=0) and a second 30-minute infusion of 250 U/kg (120 to 150 minutes). ATIII significantly prevented the development of a DIC; the increase in fibrin monomers (placebo, 11.4+/-9.1 reciprocal titers, at 6 hours) was completely overcome by ATIII (P<0. 05). ATIII significantly prevented the increase in thromboxane (TXB2) levels, which were 809+/-287 pg/mL in the placebo and 420+/-174 pg/mL in the verum group after 6 hours (P<0.02). On the other hand, ATIII had no influence on TNF levels. In a lethal study with an increased dose of LPS (0.5 microgram. kg-1. h-1). A significant reduction in mortality was observed in the ATIII group (0 of 7) compared with the placebo group (4 of 6) (P<0.05, chi2 test) a significant reduction of pulmonary hypertension (placebo, 42.0+/-11. 1 mm Hg; ATIII, 23.6+/-7.5 mm Hg, P<0.05), but no effect on systemic hypotension, was noted in the ATIII group. It was thus concluded that modulation of the procoagulatory state by substitution of ATIII results in a late beneficial antiinflammatory effect in this model of septic shock. |
| [New findings on the physiopathology of acute hemolytic transfusion reactions]. | Med Pregl | Acute hemolytic transfusion reactions (HTRs) are among the most feared transfusion-associated complications, principally because severe toxicity and rapid death may result. Recently there has been expansion in knowledge concerning the pathophysiology of shock, inflammation and disseminated intravascular coagulation, factors affecting the outcome of HTRs. A new class of biologic mediators/modulators of inflammatory and immune response, interleukins (IL) has been discovered to be of the central importance in the modulation of such responses.In models of acute IgM-mediated RBC incompatibility in experimental HTRs, plasma TNF-alpha rise sharply in a dose- and time-dependent manner, peaking at 2 hours. It is responsible for fever, hypotension and capillary leak leading to acute shock. After 4-6 hours levels of interleukin-8 and MCP-1, monocyte chemoattractants and activators of neutrophils rise, and remain in plasma significantly elevated 48 hours. In IgG-mediated HTRs, within 6 hours the concentrations of IL-1, IL-6, and IL-8 increase significantly and remain elevated next 24 hours, resulting in fever, hypotension, leucocytosis, shock, the proliferation of T-cells and stimulation of immunoglobulin production. Cytokines also play an important role in the development of disseminated intravascular coagulation (DIC). It is associated with the activation of tissue factor pathway and promoting of hypercoagulable state by their effects on endothelial cells. IL-1 and tumor necrosis factor (TNF) induce changes in the hemostatic properties of endothelial cells surface which leads to increased tissue factor and decrease thrombomodulin expression and suppression of protein C activity. Thrombin, bradykinin, epinephrine and IL-1 activation induce acute renal failure, which leads to renal hypoperfusion and widespread fibrin deposition. In etiology of acute lung injury participate: TNF, releasing large quantities of enzyme neutrophil elastase via neutrophil degranulation and pulmonary capillary endothelial injury. IL-8 and MCP-1 released from endothelial cells also promote localised inflammation and thrombosis.IL-1, TNF-alpha and IL-6 and IL-8 are all critical mediators of immune and inflammatory response and are known to synergize with each other in a number of in vitro systems. They are responsible for major signs of acute hemolytic transfusion reaction. A future therapeutic strategy of HTRs has to be aimed at modulation of underlying pathophysiologic alterations triggered by HTRs. |
| 1999 | Effect of the immunomodulating agent, pentoxifylline, in the treatment of sepsis in prematurely delivered infants: a placebo-controlled, double-blind trial. | Crit Care Med | To evaluate the influence of the methylxanthine derivative, pentoxifylline, on plasma levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, and IL-6 in prematurely delivered infants with generalized bacterial infections and to assess the effect of this immunomodulating drug on the clinical outcome in newborns with sepsis.A prospective, randomized, double-blind trial.The neonatal intensive therapy units in university teaching hospitals.One hundred patients with sepsis admitted during a 1.5-yr period.Patients were randomly assigned to receive pentoxifylline (pentoxifylline group) in a dose of 5 mg/kg/hr for 6 hrs on 6 successive days or an identically presented placebo (placebo group).Only infants with sepsis confirmed by positive blood culture were recruited into the study. There were no significant differences at randomization between the pentoxifylline and placebo groups with regard to the birth weight, gestational age, gender, Apgar score, hypotension, neutropenia, thrombocytopenia, metabolic acidosis, plasma levels of cytokines, and occurrence of shock. Plasma levels of TNF, IL-1, and IL-6 were evaluated before and after the drug or placebo administration on the first, third, and sixth days of therapy. Cytokines were determined by immunoenzymetric test EASIA (TNF) and Endogen Interleukin-Elisa (IL-1, IL-6). The frequency of gram-negative sepsis was similar in both groups (37.5% and 36.8%). Pentoxifylline significantly diminished plasma TNF levels (p = .009) but had no effect on plasma IL-1 levels. Mean plasma IL-6 levels, which were measured in the pentoxifylline group on the 6th day of the study, were significantly lower compared with respective data obtained in the placebo group. Only 1 of 40 infants with sepsis in the pentoxifylline group died, whereas 6 of 38 infants in the placebo group did not survive (p = .046). An increased incidence of disordered peripheral circulation and metabolic acidosis (p = .048), anuria or oliguria (p = .03), disseminated intravascular coagulation (p = .043), and the occurrence of clinical symptoms of necrotizing enterocolitis (p = .025) was observed in the course of sepsis in infants in the placebo group.Pentoxifylline significantly affects the synthesis of TNF and IL-6 as well as reduces the mortality rate in premature infants with sepsis. The dosage and schedule of drug administration in this study attenuated the severity of the clinical course of sepsis in this group of patients. |
| 1999 | A pilot study of melphalan, tumor necrosis factor-alpha and 41.8 degrees C whole-body hyperthermia. | Cancer Chemother Pharmacol | To evaluate the feasibilitv of sequencing (based on preclinical modeling) tumor necrosis factor-a (TNF) at two dose levels with melphalan (L-PAM) and 41.8 C whole-body hyperthermia (WBH) for 60 min.Nine patients with refractory cancer were treated from October 1995 to June 1997. The study encompassed a total of 20 trimodality treatment courses. Three patients were treated at TNF dose level I (50 microg/m2) and six patients were treated at TNF dose level II (100 microg/m2). TNF was delivered as a 24-h intravenous infusion, 48 h prior to the combination of L-PAM and WBH; L-PAM was given over 10 min at target temperature at a dose of 17.5 mg/ m2 based on a previous phase I WBH/L-PAM trial. WBH was administered with an Aquatherm radiant heat device.Myelosuppression was the major toxicity associated with therapy, but there were no instances of bleeding or neutropenic fevers. Grade 3 thrombocytopenia was seen with 15% of treatments. Regarding absolute neutrophil count, 15% of treatments were associated with grade 3 toxicity, and 45% with grade 4 toxicity, and regarding white blood cell count, 50% of treatments were associated with grade 3 toxicity and 10% with grade 4 toxicity. The myelosuppression observed was equivalent to that seen in our earlier phase I study of WBH and L-PAM (without TNF). Only mild toxicities (grade 1 or 2) were associated with TNF; these were seen with <25% of treatments and included nausea, vomiting, diarrhea, fevers, and headache. There were no instances of hypotension. There was no relationship between toxicities observed and the two TNF dose levels. Mild WBH toxicities were seen with less than 15% of treatments; these included nausea, vomiting, and herpes simplex I. Responses included two complete remissions (malignant melanoma, TNF dose level I; breast cancer, TNF dose level II), and two disease stabilizations (both malignant melanoma, TNF dose level I).We conclude that the combination of TNF, L-PAM, and WBH is well tolerated at the dose levels studied. The clinical results justify further clinical investigation for this trimodality treatment approach. |
| 1999 | Identification of a locus on distal mouse chromosome 12 that controls resistance to tumor necrosis factor-induced lethal shock. | Genomics | Administration of recombinant murine tumor necrosis factor (TNF) to mice results in lethal shock, characterized by hypotension, hypothermia, and dramatic induction of cytokines released in the circulation, such as interleukin-6 (IL-6). The sensitivity of mice to the effects of murine TNF varies from strain to strain. DBA/2 mice were found to be considerably more resistant to TNF than C57BL/6 mice. The resistance proved to be dominant since (C57BL/6 x DBA/2)F1 mice were also resistant. Using BXD recombinant inbred mice and a dose of TNF lethal for C57BL/6 but not for DBA/2 mice, we found that the resistance to TNF links to loci coding for corticosteroid-binding globulin (Cbg), alpha1-protease inhibitor (Spi1), contrapsin (Spi2) and the contrapsin-regulating gene Spi2r that form a gene cluster on chromosome 12. Quantitative trait-loci analysis of TNF-induced induction of IL-6 and of hypothermia also points to the importance of this locus (P < 0.0002 and P = 0.017, respectively), more particularly the Cbg and Spi2 loci, in the resistance to TNF. We propose to name the locus "TNF protection locus." The data suggest that endogenous protease inhibitors and/or glucocorticoids play a significant role in the attenuation of TNF-induced lethal shock. This study also demonstrates that loci affecting important biological responses can be identified with very high resolution using recombinant inbred mice. |
| 1999 | Effects of nitric oxide synthase inhibitors on systemic hypotension, cytokines and inducible nitric oxide synthase expression and lung injury following endotoxin administration in rats. | J Biomed Sci | Endotoxin shock is characterized by systemic hypotension, hyporeactiveness to vasoconstrictors and acute lung edema. A nitric oxide synthase (NOS) inhibitor, NG-monomethyl-L-arginine (L-NMMA) has been shown to be effective in reversing acute lung injury. In the present study, we evaluated the effects of NOS blockade by different mechanisms on the endotoxin-induced changes. In anesthetized rats, lipopolysaccharide (LPS, Klebsiella pneumoniae) was administered intravenously in a dose of 10 mg/kg. LPS caused sustained systemic hypotension accompanied by an eightfold increase of exhaled NO during an observation period of 4 h. After the experiment, the lung weight was obtained and lung tissues were taken for the determination of mRNA expressions of inducible NOS (iNOS), interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha-(TNF-alpha). Histological examination of the lungs was also performed. In the control group injected with saline solution, mRNA expressions of iNOS, IL-1beta and TNF-alpha were absent. Four hours after LPS, the mRNA expressions of iNOS and IL-1beta were still significantly enhanced, but TNF-alpha was not discernibly expressed. LPS also caused a twofold increase in lung weight. Pathological examination revealed endothelial damage and interstitial edema. Various NOS inhibitors were given 1 h after LPS administration. These agents included Nomega-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg), a constitutive NOS and iNOS inhibitor; S, S'-1,4-phenylene-bis-(1,2-ethanedinyl) bis-isothiourea dihydrobromide (1,4-PBIT, 10 mg/kg), a relatively specific iNOS inhibitor, and dexamethasone (3 mg/kg), an inhibitor of iNOS expression. These NOS inhibitors all effectively reversed the systemic hypotension, reduced the exhaled NO concentration and prevented acute lung injury. The LPS-induced mRNA expressions of iNOS and IL-1beta were also significantly depressed by these NOS inhibitors. Our results suggest that NO production through the iNOS pathway is responsible for endotoxin-induced lung injury. Certain cytokines such as IL-1beta are possibly involved. These changes are minimized by NOS inhibitors through different mechanisms. |
| 1998 | The influence of antibodies to TNF-alpha and IL-1beta on haemodynamic responses to the cytokines, and to lipopolysaccharide, in conscious rats. | Br J Pharmacol | Male, Long Evans rats (350-450 g) were anaesthetized and had pulsed Doppler probes and intravascular catheters implanted to allow monitoring of regional (renal, mesenteric and hindquarters) haemodynamics in the conscious state. Our main objectives were to:- assess the effects of administering human recombinant tumour necrosis factor (TNF)-alpha and human recombinant interleukin-1 (IL-1)beta, alone and together; determine the influence of pretreatment with a mixture of antibodies to TNF-alpha and IL-1beta on responses to co-administration of the cytokines; ascertain if pretreatment with a mixture of the antibodies to TNF-alpha and IL-1beta had any influence on the responses to lipopolysaccharide (LPS). TNF-alpha (10, 100 and 250 microg kg(-1), in separate groups, n=3, 9 and 8, respectively) caused tachycardia (maximum delta, +101+/-9 beats min(-1)) and modest hypotension (maximum delta, -10+/-2 mmHg), accompanied by variable changes in renal and mesenteric vascular conductance, but clear increases in hindquarters vascular conductance; only the latter were dose-related (maximum delta, +6+/-6, +27+/-9, and +61+/-12% at 10, 100 and 250 microg kg(-1), respectively). IL-1beta (1, 10, and 100 microg kg(-1) in separate groups, n = 8, 8 and 9, respectively) evoked changes similar to those of TNF-alpha (maximum delta heart rate, +69+/-15 beats min(-1); maximum delta mean blood pressure, -14+/-2 mmHg; maximum delta hindquarters vascular conductance, +49+/-17%), but with no clear dose-dependency. TNF-alpha (250 microg kg(-1)) and IL-1beta (10 microg kg(-1)) together caused tachycardia (maximum delta, +76+/-15 beats min(-1)) and hypotension (maximum A, -24+/-2 mmHg) accompanied by increases in renal, mesenteric and hindquarters vascular conductances (+52+/-6%, +23+/-8%, and +52+/-11%, respectively). Thereafter, blood pressure recovered, in association with marked reductions in mesenteric and hindquarters vascular conductances (maximum delta, -50+/-3% and -58+/-3%, respectively). Although bolus injection of LPS (3.5 mg kg(-1)) caused an initial hypotension (maximum delta, -27+/-11 mmHg) similar to that seen with co-administration of the cytokines, it did not cause mesenteric or hindquarters vasodilatation, and there was only a slow onset renal vasodilatation. The recovery in blood pressure following LPS was less than after the cytokines, and in the former condition there was no mesenteric vasoconstriction. By 24 h after co-administration of TNF-alpha and IL-1beta or after bolus injection of LPS, the secondary reduction in blood pressure was similar (-16+/-2 and -13+/-3 mmHg, respectively), but in the former group the tachycardia (+117+/-14 beats min(-1)) and increase in hindquarters vascular conductance (+99+/-21%) were greater than after bolus injection of LPS (+54+/-16 beats min ' and +439%, respectively). Pretreatment with antibodies to TNF-alpha and IL-1beta (300 mg kg(-1)) blocked the initial hypotensive and mesenteric and hindquarters vasodilator responses to co-administration of the cytokines subsequently. However, tachycardia and renal vasodilatation were still apparent. Premixing antibodies and cytokines before administration prevented most of the effects of the latter, but tachycardia was still present at 24 h. Pretreatment with antibodies to TNF-alpha and IL-1beta before infusion of LPS (150 microg kg(-1) h(-1) for 24 h) did not affect the initial fall in blood pressure, but suppressed the hindquarters vasodilatation and caused a slight improvement in the recovery of blood pressure. However, pretreatment with the antibodies had no effect on the subsequent cardiovascular sequelae of LPS infusion. the results indicate that although co-administration of TNF-alpha and IL-1beta can evoke cardiovascular responses which, in some respects, mimic those of LPS, and although antibodies to the cytokines can suppress most of the cardiovascular effects of the cytokines, the antibodies have little influence on the haemodynamic responses to LPS, possibly because, during infusion of LPS, the sites of production and local action of endogenous cytokines, are not accessible to exogenous antibodies. |
| 1998 | Effects of hyperbaric oxygen exposure on a zymosan-induced shock model. | Crit Care Med | To evaluate the effects of hyperbaric oxygen (HBO) therapy on zymosan-induced shock in rats. Zymosan, a cell wall component of the yeast Saccharomyces cerevisiae, induces inflammation by causing the production of various cytokines and pro-inflammatory mediators. The administration of zymosan to rats represents a new experimental shock model by inducing acute peritonitis, severe hypotension, and signs of systemic illness. However, it has been recently proposed that the zymosan-induced shock, like septic shock, may be mediated by overproduction of nitric oxide.Experimental study.Institute of Pharmacology and Toxicology, 2nd University of Naples, Naples, Italy.Male rats were treated with zymosan (500 mg/kg) by intraperitoneal route, with HBO (2 Absolute Atmosphere) or with zymosan and HBO (2 Absolute Atmosphere).Peritoneal exudate, plasma, and peritoneal nitric oxide metabolites (NOx) and zymosan determined a time-dependent increase in peritoneal and plasma NOx concentrations, and peritoneal leukocytes were determined. Moreover, symptomatology was observed. The administration of zymosan caused the appearance of a severe illness in the rats characterized by ruffled fur, lethargy, conjunctivitis, diarrhea, and a significant loss of body weight. All zymosan-treated rats developed an acute peritonitis, producing turbid exudate. Zymosan determined a time-dependent increase in peritoneal, plasma NOx, and tumor necrosis factor (TNF)-alpha concentrations. Morbidity of zymosan shocked rats has been attenuated and no mortality was observed by treatment with HBO. These findings were associated with a significant reduction either of peritoneal leukocytes and exudate, or plasma and peritoneal NOx concentrations. Moreover, TNF-alpha levels were significantly reduced in animals shocked by zymosan and treated with HBO. |
| Clinical experience of EET therapy for 75 advanced cancer patients. | Anticancer Res | Exogenous/endogenous TNF (EET) therapy has a strong effect which causes inflammation in the body. Together with the antitumor effect of a single administration, the complementary effect of immunotherapy based on specific immunostimulation of tumor cells is also expected. We studied the characteristics of EET therapy in cases of advanced cancer.The patients were 75 cases with advanced cancer including 48 cases of colon cancer, 10 cases of urological cancer, and 9 cases of gynecological cancer. One course of therapy was composed of the intravenous administration of either IFN-gamma or TNF-SAM2 followed 3 hours later by OK-432. At least 2 courses were repeated during a 2 weeks period.As response cases, partial response (PR) was observed in 7 of the 42 cases of colon cancer (17%) which had an evaluable lesion. Objective responses of lung metastases were found in the patients with multiple organ metastases of cervical cancer, ovarian cancer and uterine rhabdomyosarcoma. The group of colorectal cancer patients with liver metastases which underwent more than 5 courses of the therapy showed a longer survival period compared to the control group. One of the side effects, transitory hypotension, was observed in 46% of the cases.In spite of restricted objective responses to date with EET therapy alone, anticancer effects observed in various kinds of tumors and activation of a cytokine network by which Th1 cells might be specifically activated suggest that a new biotherapy based on EET therapy may have potential. |
| 1998 | Sulfatide reduces leucocyte accumulation and reverts vascular failure in splanchnic artery occlusion shock. | Eur J Pharmacol | Selectin-mediated leucocyte accumulation is implicated in the pathogenesis of splanchnic artery occlusion. Sulfatide is recognized by P-selectin and blocks this adhesion molecule. We investigated the effects of sulfatide in rats subjected to splanchnic artery occlusion shock. Anaesthetized rats, subjected to total occlusion of the superior mesenteric artery and the coeliac trunk for 45 min developed severe shock resulting in death within 85-90 min after the release of occlusion. Sham operated animals were used as controls. Splanchnic artery occlusion shocked rats had marked hypotension, enhanced levels of tumor necrosis factor-alpha (TNF-alpha) in serum and macrophages, leucopenia and increased ileal leucocyte accumulation, studied by the means of myeloperoxidase activity. Furthermore, aortae from shocked rats showed marked hyporeactivity to phenylephrine (1 nM-10 microM), reduced responsiveness to acetylcholine (10 nM-10 microM) and an increased staining for P-selectin in the vasculature. In vivo administration of sulfatide (10 mg/kg, i.v., 5 min after occlusion of the splanchnic arteries) increased survival rate (90%, 4 h after splanchnic artery occlusion shock), enhanced mean arterial blood pressure, reduced serum TNF-alpha (37 +/- 11 U/ml vs. 398 +/- 18 U/ml), ameliorated leucopenia and reduced ileal myeloproxidase activity (1.2 +/- 0.4 U/g tissue vs. 8.2 +/- 0.8 U/g tissue). Aortae from splanchnic artery occlusion shocked rats treated with sulfatide exhibited a greater contractile response to phenylephrine and improved responsiveness to acetylcholine. Moreover sulfatide-treated rats showed a reduced staining for P-selectin in the aorta and in the superior mesenteric artery. Finally, passive immunization with specific monoclonal antibodies raised against P-selectin significantly protected from the lethality induced by splanchnic artery occlusion shock. Our results suggest that sulfatide protects against splanchnic artery occlusion shock. |
| 1998 | Liver as a focus of impaired oxygenation and cytokine production in a porcine model of endotoxicosis. | Crit Care Med | To determine whether the liver is a focus of insufficient oxygenation and whether liver is a source of tumor necrosis factor (TNF) and interleukin-6 (IL-6) in a porcine model of endotoxicosis.In vivo, prospective, controlled, repeated-measures, experimental study.Experimental physiology laboratory in a university.Juvenile pigs, weighing 22 to 35 kg.Catheters for blood sampling were inserted into the carotid artery, portal vein, hepatic vein, and pulmonary artery of anesthetized animals. Ultrasonic flow probes were placed on the portal vein and the hepatic artery. During surgery, normal saline was infused intravenously at 25 mL/kg/hr. Following stabilization, animals were allocated randomly to one of two groups. The endotoxemic group (n = 6) received 50 mg/kg of purified Escherichia coli lipopolysaccharide infused into the external jugular vein over 1 hr. The control group (n = 6) received a sham saline infusion infused over 1 hr. Once the endotoxin or sham infusion was initiated, the rate of the intravenous saline infusion was increased to 48 mL/kg/hr for the remainder of the experiment. Measurements were obtained before the endotoxin or sham infusion, immediately after the infusion, and every 30 mins thereafter for 4 hrs.Blood gases, lactate, and bioactive TNF and IL-6 concentrations were measured from the carotid artery, portal vein, hepatic vein, and pulmonary artery. The porcine model is characterized by systemic hypotension, pulmonary hypertension, and maintenance of cardiac output. Despite decreased hepatic oxygen delivery in endotoxemic animals (p < .02), there was no change in hepatic oxygen consumption compared with controls. Throughout the experiment, there was net hepatic consumption of lactate in both groups. There was no significant hepatic production (or consumption) of TNF or IL-6 in either group.In this porcine model of endotoxicosis, there is a reduction of hepatic oxygen delivery but dysoxia is not present. The liver is not a source of TNF or IL-6 in this model of endotoxicosis. |
| 1998 | Macrophage inflammatory protein-2 predicts acute lung injury in endotoxemia. | J Investig Med | Proinflammatory mediators that include tumor necrosis factor-alpha (TNF-alpha) and macrophage inflammatory protein-2 (MIP-2) and anti-inflammatory mediators such as interleukin-10 (IL-10) modulate the immune response to endotoxemia. IL-10 downregulates the production of TNF-alpha and MIP-2. Acute lung injury may occur secondary to neutrophil chemotaxis mediated by chemokine MIP-2. We studied the temporal relationship of TNF-alpha, MIP-2, and IL-10 in rat endotoxemia and correlation of MIP-2 concentrations with acute lung injury.Ten ventilated rats were randomized to receive an intravenous infusion of 2 mg/kg Escherichia coli lipopolysaccharide (n = 6) or saline placebo (n = 4). Blood pressure was continuously monitored and arterial blood was obtained for lactate, blood gas, TNF-alpha, IL-10, and MIP-2 measurements at baseline, 2, 4, and 5.5 hours after LPS or saline infusion.Endotoxemia resulted in hypotension, lactic acidemia, and increased alveolar-arterial oxygen gradient (A-a O2 gradient) compared with the placebo group. TNF-alpha, MIP-2, and IL-10 levels were increased 2 hours after endotoxemia. Subsequently, TNF-alpha levels declined while IL-10 and MIP-2 levels remained elevated. Control rats had no significant increase in cytokine production at any time point. MIP-2 concentrations correlated with A-a O2 gradient, an indicator of lung injury (r = 0.56, p < 0.001).MIP-2, possibly released by TNF-alpha stimulation of macrophages, is associated with acute lung injury possibly by inducing neutrophil chemotaxis. IL-10 may exert its counter-inflammatory response by inhibiting the release of TNF-alpha in endotoxemia. |
| 1998 | Inhibition of tumour necrosis factor and reversal of endotoxin-induced shock by U-83836E, a 'second generation' lazaroid in rats. | Br J Pharmacol | 1. Antioxidants can exert protective effects in endotoxic shock by either a reduction of the oxidant damage or attenuation of Tumour Necrosis Factor (TNF-alpha) production. 2. Lazaroids are a family of compounds that inhibit lipid peroxidation. Besides, they can also reduce TNF-alpha. U-83836E is a new lazaroid lacking the glucocorticoid ring. 3. Aim of our study was to investigate the effect of U-83836E on TNF-alpha production either in vivo or in vitro. Endotoxic shock was produced in male rats by a single intravenous (i.v.) injection of 20 mg kg(-1) of S. enteritidis lipopolysaccharide (LPS). LPS administration reduced survival rate (0% survival, 72 h after endotoxin administration), decreased mean arterial blood pressure, increased serum and macrophage TNF-alpha and enhanced plasma malonylaldehyde (MAL) levels. Furthermore aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE 1 nM-10 microM). 4. Treatment with U-83836E (7.5, 15 and 30 mg kg(-1), i.v.) 5 min after endotoxin challenge significantly protected against LPS induced lethality (90% survival rate and 80% survival rate 24 h and 72 h after LPS injection respectively, following the highest dose of the drug), reduced hypotension, blunted plasma MAL, decreased serum and macrophage TNF-alpha and restored the hyporeactivity of aortic rings to control values. In vitro LPS stimulation (50 microg ml(-1) for 4 h) significantly increased cytokine production in macrophages (Mphi) harvested from untreated normal rats. Pretreatment with pertussis toxin (PT; 0.1, 1 and 10 ng ml(-1) 4 h before LPS) significantly increased TNF-alpha production. PT effects on these LPS responses were correlated with a PT mediated ADP ribosylation of a 41 kDa protein. U-83836E (50 microM) reduced, in a dose dependent manner, LPS induced TNF-alpha production and inhibited the PT effects on cytokine production and on ADP ribosylation of the protein. 5. Our data suggest that lazaroids may affect the early events associated with LPS receptor mediated activation of a G protein in LPS induced TNF-alpha production. These molecular events may explain, at least in part, the in vivo inhibition of cytokine production and reversal of endotoxic shock. |
| 1998 | Nitric oxide production in experimental gram-negative infection: studies with cytokine receptor-deficient mice. | Shock | Overproduction of nitric oxide (NO) upon expression of inducible NO synthase (iNOS) may be responsible for refractory hypotension in septic shock. Whereas high levels of NOS activity have been documented in experimental models of endotoxemia or intravenous challenge with Escherichia coil, much less is known concerning tissue models of Gram-negative infection. We examined NO production (measured as the accumulation of plasma NO3- + NO2-) in a murine model of Gram-negative peritonitis. Plasma NO3- + NO2- increased progressively from 25 microM to peak levels of 50-150 microM 24 h after intraperitoneal challenge with E. coli 0111:B4, similar to values reported for septic shock patients. Treatment of infected mice with NG-monomethyl-L-arginine, an inhibitor of NOS activity, resulted in the efficient inhibition of NO3- + NO2- production. In order to evaluate the roles of interferon-gamma (IFN-gamma) and tumor necrosis factor (TNF-alpha) in the induction of NO synthesis in murine peritonitis, mice deficient in the respective cytokine receptors were studied. In control in vitro experiments, macrophages from IFN-gammaR- or TNFR55-deficient mice, while failing to respond to IFN-gamma or TNF-alpha, respectively, produced high levels of NO under appropriate stimulation. When challenged intraperitoneally with E. coli, IFN-gammaR- or TNFR55-deficient mice exhibited similar levels of bacteremia and NO production as their wild-type controls. These data thus suggest that enhanced NO production during focal Gram-negative infection may occur in the absence of signaling through either IFN-gammaR or TNFR55. |
| Pyrrolidine dithiocarbamate improves the septic shock syndromes in spontaneously hypertensive rats. | Clin Exp Pharmacol Physiol | 1. The aim of the present study was to evaluate the effect of pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor-kappa B (NF-kappa B), on septic shock induced by Escherichia coli lipopolysaccharide (LPS) in spontaneously hypertensive rats (SHR). 2. After injection of LPS in SHR, a marked decrease in blood pressure was observed at 3 h and vascular hyporeactivity to noradrenaline (NA) was observed after 1 h. A marked increase in plasma levels of tumour necrosis factor-alpha (TNF-alpha) and nitrite (an indicator of nitric oxide) was also observed in SHR. 3. The delayed hypotension and hyporeactivity to NA induced by LPS were significantly reserved by pretreatment of rats with PDTC (10 mg/kg). The increase in plasma levels of TNF-alpha and nitrite in LPS-treated groups was also significantly suppressed by PDTC pretreatment. In addition, the survival time of SHR treated with LPS was significantly prolonged by PDTC pretreatment. 4. The present ex vivo study demonstrates that the NA-induced contraction is attenuated and the L-arginine-induced relaxation is enhanced in aortic rings obtained from LPS-treated SHR. Both the reduction of the NA-induced contraction and the increase of L-arginine-induced relaxation were reversed by pretreatment with PDTC. However, the relaxation elicited by acetylcholine (ACh) was not affected in LPS-treated SHR when compared with sham-operated SHR. In addition, the ACh-induced relaxation in LPS-treated SHR was not affected by PDTC pretreatment. 5. In normotensive Wistar-Kyoto (WKY) rats, LPS had mild effects on blood pressure, vascular hyporeactivity and plasma levels of TNF-alpha and nitrite. At a higher dose, PDTC (10 mg/kg) also prolonged survival time and improved haemodynamics in LPS-treated WKY rats. In the ex vivo study, it was noted that the relaxation elicited by ACh was significantly (P < 0.05) attenuated in LPS-treated WKY rats. This attenuation of the ACh-induced relaxation by LPS in WKY rats was significantly reversed by pretreatment with 10 mg/kg PDTC. 6. In conclusion, PDTC prolongs survival time in rats with endotoxaemia and improves the septic shock syndromes both in vivo and ex vivo. Thus, we propose that PDTC may be of use in septic patients. |
| 1998 | Resistance to endotoxin shock in spontaneously hypertensive rats. | Hypertension | Septic shock involves systemic vasodilation mediated by proinflammatory cytokines. In essential hypertension, vascular and immune dysfunctions are closely associated. The response of hypertensive animals compared with normotensive controls to endotoxin (lipopolysaccharide; LPS) challenge is not known. Age-matched (12 weeks) normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were exposed to intravenous injection of 10 mg/kg LPS. Survival rate at 24 hours was markedly higher in SHR than in WKY (12 of 15 and 3 of 15, respectively; P<0.01). Survival of LPS-injected SHR was not related to their hypertension because hydralazine-treated SHR with normalized pressure had similar survival rates, and WKY made hypertensive by clipping of one renal artery showed fatality similar to that of normotensive WKY. Continuous arterial pressure and sequential plasma levels of interleukin-6 (IL-6) and tumor necrosis factor (TNF) were measured in LPS-treated SHR and WKY. Both the duration of the delayed hypotensive phase and the systemic release of IL-6 were much lower in SHR than WKY, whereas both acute hypotension and plasma TNF peak were equivalent. We further explored in vitro the inflammatory response and showed that LPS-activated whole blood from SHR produced less TNF and IL-6 than WKY LPS-activated whole blood. Our results indicate that SHR have a greater ability to resist endotoxic shock than WKY. This is not related to their hypertension but is associated with an attenuated inflammatory response to LPS. |
| 1998 | Cholestatic liver injury increases circulating TNF-alpha and IL-6 and mortality after Escherichia coli endotoxemia. | Am J Respir Crit Care Med | We employed a bile duct ligation (BDL) model of cholestatic liver injury to test the hypothesis that this form of preexisting hepatic dysfunction alters the kinetics of circulating TNF-alpha and IL-6 after Escherichia coli endotoxemia, thereby augmenting mortality and lung injury by a TNF-alpha:leukotriene (LT) axis of inflammation. Male rats were catheterized 13 d after BDL or sham surgery and studied while awake 18 to 24 h later. Cholestasis after BDL was confirmed by baseline serum bilirubin (BDL = 7.34 +/- 0.72 mg/dl, mean +/- SEM, n = 17 versus Sham = 0.25 +/- 0.07, n = 20; p < 0.005) and histopathology. Sham and BDL animals received E. coli lipopolysaccharide serotype O55:B5 (LPS, 5 mg/kg i.v.) or 0.9% NaCl (NS) ending at t = 0 and were monitored over 24 h for vital signs and hemodynamics. In parallel studies, lipoxygenase inhibition was performed using diethylcarbamazine or the 5-lipoxygenase activating-protein inhibitor MK-886. Blood was collected at baseline and at t = 1.5, 3.5, and 24 h for formed elements and for serum endotoxin, TNF-alpha, IL-6, bilirubin, and alanine aminotransferase (ALT). Organs were evaluated at 24 h for histopathology, including neutrophil (PMN) densities and wet/dry weight (W/D) ratios. Cholestasis reduced survival after otherwise nonlethal endotoxemia, with seven of 11 BDL + LPS rats dying within 24 h versus no deaths in BDL + NS (n = 6), Sham + LPS (n = 14), or Sham + NS (n = 6) animals (p < 0.01). Despite equivalent serum endotoxin between groups, circulating TNF-alpha was 8-fold higher in BDL + LPS than in Sham + LPS rats at 1.5 and 3.5 h (p < 0.001), whereas serum TNF-alpha did not differ between BDL + NS and Sham + NS rats. IL-6 likewise was increased differentially by 1.5 h in BDL + LPS animals (11.98 +/- 2.42 ng/ml) versus Sham + LPS rats (3.05 +/- 0.58 ng/ml, p < 0.05). Hypothermia, bradycardic hypotension, and leukopenia were most severe and prolonged in BDL + LPS rats, which also had significantly higher ALT values, W/D ratios, and organ PMN counts. LT inhibition failed to reduce BDL-related differences in serum cytokines or survival after endotoxemia. Thus, cholestasis augments inflammatory responses to gram-negative endotoxemia, sensitizing the host to enhanced fluid flux in multiple organs and to mortality by a LT-independent mechanism. |
| 1998 | Beneficial effects of tetramethylpyrazine, an active constituent of Chinese herbs, on rats with endotoxemia. | Proc Natl Sci Counc Repub China B | Tetramethylpyrazine, an inhibitor of phosphodiesterase, has been widely used for treatment of cardiovascular diseases in China. Here, we investigate the effects of tetramethylpyrazine on hypotension, vascular hyporeactivity to norepinephrine (NE), release of tumor necrosis factor-alpha (TNF alpha) and nitric oxide (NO) in a rat model of circulatory shock induced by bacterial endotoxin (E. coli lipopolysaccharide, LPS). Male Wistar-Kyoto rats were anesthetized and instrumented for the measurement of mean arterial pressure (MAP) and heart rate (HR). Injection of LPS (10 mg/kg, i.v.) resulted in a fall in MAP and an increase of HR. In contrast, animals pretreated with tetramethylpyrazine (10 micrograms/kg, i.p. at 30 min prior to LPS) maintained a significantly higher MAP, but tachycardia was further enhanced at 60 min and 120 min when compared to rats given only LPS (LPS-rats). The pressor effect of NE (1 microgram/kg, i.v.) was also significantly reduced after treatment of rats with LPS. Similarly, the thoracic aorta obtained from rats after in vivo studies showed a significant reduction in the contractile responses elicited by NE (1 microM). Pretreatment of LPS-rats with tetramethylpyrazine partially, but significantly, prevented this LPS-induced hyporeactivity to NE in vivo and ex vivo. The injection of LPS resulted in a significant increase in the plasma TNF alpha level at 60 min, whereas the effect of LPS on the plasma nitrate (an indicator of NO formation) level increased in a time-dependent manner. This increment of both TNF alpha and nitrate levels induced by LPS was significantly reduced in LPS-rats pretreated with tetramethylpyrazine. The early hypotension caused by LPS was slightly, but significantly, prevented by pretreatment with tetramethylpyrazine, suggesting that tetramethylpyrazine affects the endothelial constitutive NOS (eNOS). This was examined by the effect of tetramethylpyrazine on acetylcholine (ACh, 1 microM)-induced relaxation in rats treated with tetramethylpyrazine for 4 h. However, tetramethylpyrazine had no significant effects on the ACh-induced relaxation, indicating that tetramethylpyrazine does not affect the activity of eNOS. Thus, tetramethylpyrazine attenuates the early hypotension and the delayed circulatory failure caused by endotoxin in the rat. These effects may be due to inhibition of the release of circulation factors and TNF alpha, which usually reveal synergism upon the induction of iNOS. |
| 1998 | Prevalence of hypophosphatemia in sepsis and infection: the role of cytokines. | Am J Med | Sepsis occurs following the presence of bacteria in the circulation and is associated with fever, hyperthermia, and hypotension. Hypophosphatemia develops in the early stages of sepsis. High levels of inflammatory cytokines also characterize early sepsis.The aim of the present study was to correlate hypophosphatemia with cytokines and cytokine receptor levels during early sepsis. We aimed to reestablish the results obtained from patients in an in vivo experimental model, in order to understand the mechanism of hypophosphatemia induction in early sepsis.Ninety-nine patients were enrolled in this study and their clinical condition was classified as the presence of infection, sepsis, and bacterial growth in blood cultures. Phosphate levels and cytokine levels were recorded. In order to determine whether hypophosphatemia is correlated to the increased inflammatory cytokines, we injected normal mice with recombinant cytokines and studied their effect on phosphate levels.Our results revealed that 80% of the septic patients had hypophosphatemia associated with very high levels of tumor necrosis factor (TNF)alpha and interleukin (IL)-6 and of soluble IL receptor (sIL)-2R and IL-6R, especially in those patients with positive blood cultures. Injection of IL-6, TNFalpha and IL-1beta in mice markedly decreased the phosphate serum levels.Significant associations were demonstrated between high levels of inflammatory cytokines and their receptors and between serum phosphate levels, especially in patients with positive blood culture. Our results point to a correlation between the high inflammatory cytokines levels and hypophosphatemia during early sepsis. Cytokine levels and hypophosphatemia may be included in sepsis evaluation and prognosis. Anticytokine strategies might, therefore, reverse hypophosphatemia and other parameters of sepsis. |
| 1998 | Early release of proinflammatory cytokines after lung transplantation. | Chest | Systemic hypotension may complicate the early postoperative period after lung transplantation. A release of proinflammatory cytokines secondary to lung ischemia/reperfusion injury could be involved in the pathogenesis of this early hemodynamic failure (EHF).To assess prospectively whether the occurrence of EHF is associated with a release of cytokines in the systemic circulation.Blood samples were taken daily during the first postoperative week in 26 patients who underwent a double or a single-lung transplantation. These patients were divided into three groups: 7 patients who experienced EHF and subsequently died (EHF group); 15 patients without EHF (control group); and 4 patients without EHF but with an identified sepsis (sepsis group). The serum levels of interleukin (IL)-1beta, tumor necrosis factor-alpha (TNF-alpha), IL-6, and IL-8 were compared among the three groups.In the EHF group, the levels of each cytokine peaked at day 1 postoperatively. Cytokine levels at day 1 were significantly higher in the EHF group than in the control group (p<0.0006) or in the sepsis group (p<0.003 except for TNF-alpha).We conclude that EHF is associated with a massive release of proinflammatory cytokines that could play a determinant role in the pathogenesis of this complication. |
| 1998 | Effects of the lazaroid, tirilazad mesylate, on sepsis-induced acute lung injury in minipigs. | Crit Care Med | To assess the effects of the lazaroid, tirilazad mesylate, a potent lipid peroxidation inhibitor, in an animal model of Pseudomonas sepsis.Comparison of four experimental groups: a) saline control; b) Pseudomonas sepsis control; c) tirilazad mesylate control; and d) sepsis with tirilazad mesylate pre treatment.University animal laboratory.Hanford minipigs (20 to 25 kg), anesthetized with pentobarbital and mechanically ventilated on an FIO2 of 0.4.Sepsis was induced by infusing Pseudomonas aeruginosa at 1 x 10(6) colony-forming units/kg/min over 120 mins. The tirilazad mesylate-treated group received a 5-mg/kg bolus 30 mins before, and a 3-mg/kg bolus 3 hrs after, the onset of sepsis. Hemodynamics, PaO2, and neutrophil counts were measured for 6 hrs. Thiobarbituric acid reactive material (TBARM) in tissue (lung, liver, and intestine), lung wet/dry weight ratio, lung myeloperoxidase activity, plasma tumor necrosis factor (TNF)-alpha concentrations, protein content, and percent neutrophils in bronchoalveolar lavage fluid were evaluated at the time the animals were killed (6 hrs).Sepsis induced significant systemic hypotension, pulmonary hypertension, hypoxemia, and neutropenia. Sepsis also significantly increased TBARM content, lung wet/dry weight ratio, myeloperoxidase activity, plasma TNF-alpha concentrations, and bronchoalveolar lavage neutrophil percentage. Treatment with tirilazad mesylate significantly attenuated hypoxemia and decreased TBARM content, lung wet/dry weight ratio, myeloperoxidase activity, bronchoalveolar lavage protein, and bronchoalveolar lavage neutrophil percentage, but did not affect sepsis-induced hemodynamics, including systemic hypotension and pulmonary hypertension, plasma TNF-alpha concentrations, or neutropenia.Pretreatment with the tirilazad mesylate did not change P. aeruginosa sepsis-induced hemodynamic consequences. However, tirilazad mesylate attenuated sepsis-induced acute lung injury. |
| 1998 | Shedding kinetics of soluble tumor necrosis factor (TNF) receptors after systemic TNF leaking during isolated limb perfusion. Relevance to the pathophysiology of septic shock. | J Clin Invest | We examined the kinetics of shedding of the soluble TNF receptors (TNF-Rs) in response to TNF leakage during isolated limb perfusion procedures and correlated them to the resulting hemodynamic effects. Shedding of the TNF-Rs started 7 min after TNF leakage into the systemic circulation. Three waves of shedding were observed peaking at 1, 8-12, and 48-72 h both in vivo and in cell cultures. The soluble receptors prolonged the half-life of TNF in the systemic circulation to 2.5-6 h. Excess shedding of the p75 compared with p55 TNF-Rs was noted during the first wave. The amount and speed of shedding of the p75 TNF-Rs were proportional to the serum TNF levels (P < 0.001). A maximal shedding capacity was attained only during the first wave of shedding, at TNF concentrations of approximately 1.5 ng/ml. Above this level, the linearity between TNF and its soluble receptors was lost. TNF-induced hypotension coincided with the initial imbalance between the concentrations of TNF and its soluble receptors. Despite the spontaneous correction of this imbalance at 8-12 h, the hemodynamic and biochemical alterations persisted and were further aggravated at 18 h, suggesting that other factors induced earlier by TNF are responsible for the perpetuation of the hemodynamic instability. This study may provide the basis for a more physiological therapeutic approach to TNF neutralization in septic shock patients. |
| 1998 | Induction of tumor necrosis factor-alpha as a cause of bleomycin-related toxicity. | Cancer | The application of bleomycin is characterized by acute side effects, such as fever, chills, and sometimes hypotension and tachypnea. Furthermore, bleomycin is known to induce pneumonitis. There are several indications that the induction of cytokines by bleomycin is involved in the development of these side effects.In this study, the authors determined the plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and transforming growth factor-beta (TGF-beta) before and after bleomycin infusion in 14 patients treated for disseminated nonseminomatous germ cell tumor.Compared with the pretreatment value, TNF-alpha was significantly increased 3, 4.5, and 24 hours after bleomycin infusion. For IL-1beta and TGF-beta, no significant alterations were observed within 24 hours after administration of bleomycin.The increase in TNF-alpha after administration of bleomycin suggests a role for this cytokine in the development of the acute side effects and probably also in the occurrence of bleomycin-induced pulmonary toxicity. The involvement of IL-1beta and TGF-beta deserve further study. |
| 1997 | TNF-alpha causes reversible in vivo systemic vascular barrier dysfunction via NO-dependent and -independent mechanisms. | Am J Physiol | Tumor necrosis factor (TNF-alpha) and nitric oxide (NO) are important vasoactive mediators of septic shock. This study used a well-characterized quantitative permeation method to examine the effect of TNF-alpha and NO on systemic vascular barrier function in vivo, without confounding endotoxemia, hypotension, or organ damage. Our results showed 1) TNF-alpha reversibly increased albumin permeation in the systemic vasculature (e.g., lung, liver, brain, etc.); 2) TNF-alpha did not affect hemodynamics or blood flow or cause significant tissue injury; 3) pulmonary vascular barrier dysfunction was associated with increased lung water content and impaired oxygenation; 4) TNF-alpha caused inducible nitric oxide synthase (iNOS) mRNA expression in the lung and increased in vivo NO production; 5) selective inhibition of iNOS with aminoguanidine prevented TNF-alpha-induced lung and liver vascular barrier dysfunction; 6) aminoguanidine prevented increased tissue water content in TNF-alpha-treated lungs and improved oxygenation; and 7) nonselective inhibition of NOS with NG-monomethly-L-arginine increased vascular permeation in control lungs and caused severe lung injury in TNF-alpha-treated animals. We conclude that 1) TNF-alpha reversibly impairs vascular barrier integrity through NO-dependent and -independent mechanisms; 2) nonselective NOS inhibition increased vascular barrier dysfunction and caused severe lung injury, whereas selective inhibition of iNOS prevented impaired endothelial barrier integrity and pulmonary dysfunction; and 3) selective inhibition of iNOS may be beneficial in treating increased vascular permeability that complicates endotoxemia and cytokine immunotherapy. |
| 1997 | Glucose modulates hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide in rabbits. | J Appl Physiol (1985) | Glucose is important for vascular and immunocompetent cell functions. We hypothesized that modifications in glucose metabolism (normal feeding, 24-h fasting, glucose loading) may influence the hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide administration (LPS; 600 micrograms/kg iv) in rabbits. Aortic (ABFV), hepatic artery (HABFV), and portal vein blood flow velocities (PVBFV) (pulsed Doppler), plasma tumor necrosis factor (TNF) and nitrites were measured. Fasting depleted hepatic glycogen content, and intraportal glucose load (2 g/kg) partially restored it. LPS induced a similar hypotension (-20%, P < 0.05) in three groups of animals. In fed animals, systemic vasoconstriction occurred with low ABFV and PVBFV (-40%, P < 0.05), together with lactacidemia and hyperglycemia. In fasted animals, ABFV and PVBFV were maintained, without metabolic acidosis or hyperglycemia. Glucose loading induced hemodynamic and metabolic patterns comparable to those observed in fed animals, although significantly more severe. TNF release was amplified fourfold by glucose loading, with no impact on nitrite levels. In conclusion, glucose metabolism interferes with hemodynamic, metabolic, and inflammatory responses to LPS. |
| 1997 | The macrophage scavenger receptor type A is expressed by activated macrophages and protects the host against lethal endotoxic shock. | J Exp Med | During gram-negative bacterial infections, lipopolysaccharide (LPS) stimulates primed macrophages (Mphi) to release inflammatory mediators such as tumor necrosis factor (TNF)-alpha, which can cause hypotension, organ failure, and often death. Several different receptors on Mphi have been shown to bind LPS, including the type A scavenger receptor (SR-A). This receptor is able to bind a broad range of polyanionic ligands such as modified lipoproteins and lipoteichoic acid of gram-positive bacteria, which suggests that SR-A plays a role in host defense. In this study, we used mice lacking the SR-A (SRKO) to investigate the role of SR-A in acquired immunity using a viable bacillus Calmette Guérin (BCG) infection model. We show that activated Mphi express SR-A and that this molecule is functional in assays of adhesion and endocytic uptake. After BCG infection, SRKO mice are able to recruit Mphi to sites of granuloma formation where they become activated and restrict BCG replication. However, infected mice lacking the SR-A are more susceptible to endotoxic shock and produce more TNF-alpha and interleukin-6 in response to LPS. In addition, we show that an antibody which blocks TNF-alpha activity reduces LPS-induced mortality in these mice. Thus SR-A, expressed by activated Mphi, plays a protective role in host defense by scavenging LPS as well as by reducing the release by activated Mphi of proinflammatory cytokines. Modulation of SR-A may provide a novel therapeutic approach to control endotoxic shock. |
| 1997 | Circulating endotoxin and cytokines after cardiopulmonary bypass: differential correlation with duration of bypass and systemic inflammatory response/multiple organ dysfunction syndromes. | Clin Immunol Immunopathol | Cardiopulmonary bypass constitutes an injury that may cause postoperative pathophysiological changes due to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). These complications include coagulopathy, hypotension, capillary leakage, and multiple organ injury. To investigate the role of endotoxin and cytokines in the response to bypass injury, we measured plasma levels of endotoxin and proinflammatory cytokines in 20 pediatric patients before and after bypass. Clinical data, including duration of injury and tests indicative of SIRS/MODS, were collected. Levels of endotoxin, TNF-alpha, IL-6, and IL-8 but not IL-1 beta were significantly increased after bypass. Most of the cytokines have been found to correlate with each other. Endotoxin did not correlate with duration of bypass, cytokines, or SIRS/MODS. In contrast, TNF-alpha and IL-8 correlated with duration of bypass and were associated with SIRS/MODS. Certain clinical complications were associated with specific cytokines. Understanding the role of cytokinemia in SIRS/MODS may lead to better prognostic assessment and therapeutic modalities. |
| 1997 | Isolation limb perfusion with tumor necrosis factor alpha and chemotherapy for advanced extremity soft tissue sarcomas. | Semin Oncol | The unique property of high dose recombinant tumor necrosis factor alpha (rTNF alpha) is to activate and selectively destroy the tumor-associated microvasculature. For the systemic application of rTNF alpha it has been shown that the maximum tolerated dose (MTD) is 10 times less than the effective dose in animals. The main toxicity corresponds to systemic inflammatory response syndrome with a decrease in vascular resistance and hypotension. We found that it is possible to administer rTNF alpha at 10 times the MTD in an isolated limb perfusion (ILP) system with heart-lung machine, for locally advanced extremity soft tissue sarcomas. One hundred forty patients received an ILP with high-dose TNF alpha. In 55 patients treated with the combination of high-dose rTNF alpha + interferon-gamma + melphalan an overall objective response rate of 87% with 36% complete responses was observed; it was 81% and 28%, respectively, in a group treated with TNF alpha and melphalan (n = 85). Angiographic and immunohistological studies showed the selective and early damage of the sarcoma-associated microvasculature preceded by the upregulation of adhesion molecules and intratumoral leak of von Willebrand factor. Tumor invasion by platelets and, in some cases, by polymorphonuclear cells, appeared within hours after the application of rTNFa long before the lysis of the tumor. Thus, ILP with high-dose TNF alpha and chemotherapy seems to act through a dual targeting: TNF hits the tumor associated vasculature, and chemotherapy attacks the tumor cells. Therefore, ILP with TNF is a new option in the management of locally advanced soft tissue sarcoma of the extremities. |
| 1997 | Effects of tyrphostins and genistein on the circulatory failure and organ dysfunction caused by endotoxin in the rat: a possible role for protein tyrosine kinase. | Br J Pharmacol | 1 Here we compared the effects of various inhibitors of the activity of protein tyrosine kinase on (i) the expression of the activity of the inducible isoform of nitric oxide (NO) synthase (iNOS) caused by endotoxin (lipopolysaccharide, LPS) in cultured macrophages, (ii) the induction of iNOS and cyclooxygenase 2 (COX-2) protein and activity in rats with endotoxaemia, and (iii) the circulatory failure and organ dysfunction caused by LPS in the anesthetized rat. 2 Activation of murine cultured macrophages with LPS (1 microgram ml-1) resulted, within 24 h, in a significant increase in nitrite (an indicator of the formation of NO) in the cell supernatant. This increase in nitrate was attenuated by the tyrphostins AG126, AG556, AG490 or AG1641 or by genistein in a dose-dependent fashion (IC50: approximately 15 microM). In contrast, tyrphostin A1 (an analogue of tyrphostin AG126) or daidzein (an analogue of genistein) had no effect on the rise in nitrite caused by LPS. 3 Administration of LPS (E. coli, 10 mg kg-1, i.v.) caused hypotension and a reduction of the pressor responses elicited by noradrenaline (NA, 1 microgram kg-1, i.v.). Pretreatment of rats with the tyrphostins AG126, AG490, AG556, AG1641 or A1 attenuated the circulatory failure caused by LPS. Although genistein attenuated the vascular hyporeactivity to NA, it did not affect the hypotension caused by LPS. Daidzein did not affect the circulatory failure caused by LPS. 4 Endotoxaemia for 360 min resulted in rises in the serum levels of (i) urea and creatinine (indicators of renal failure), (ii) alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin and gamma-glutamyl transferase (gamma GT) (indicators of liver injury/dysfunction), lipase (an indicator of pancreatic injury) as well as lactate (an indicator of tissue hypoxia). None of the tyrosine kinase inhibitors tested had a significant effect on the rise i the serum levels of urea, but the tyrphostins AG126, AG556 or A1 significantly attenuated the rises in the serum level of creatinine caused by LPS. In addition, all tyrphostins and genistein attenuated the liver injury/failure, the pancreatic injury, the hypoglycaemia and the lactic acidosis caused by LPS. In contrast, daidzein did not reduce the organ injury/dysfunction or the lactic acidosis caused by LPS. 5 Injection of LPS resulted (within 90 min) in a substantial increase in the serum level of tumor necrosis factor alpha (TNF alpha), which was attenuated by pretreatment of LPS-rats with any of the tyrphostins used. Genistein, but not daidzein, also reduced the rise in the serum levels of TNF alpha caused by LPS. Endotoxaemia for 6 h also resulted in a substantial increase in the expression of iNOS and COX-2 protein and activity in the lung, which was attenuated by pretreatment of LPS-rats with the tyrphostins AG126, AG556 or genistein, but not by daidzein. 6 Thus, tyrphostins (AG126, AG556, AG1641 or A1) and genistein, but not daidzein (inactive analogue of genistein), prevent the (i) circulatory failure, (ii) the multiple organ dysfunction (liver and pancreatic dysfunction/injury lactacidosis, hypoglycaemia), as well as (iii) the induction of iNOS and COX-2 protein and activity in rats with endotoxic shock. |
| 1997 | Comparison of hypotensive response to aggregated IgG or to bacterial LPS in rats. | Inflamm Res | Rats treated with aggregated IgG (Aggr.) become "refractory" to the hypotensive action of a second dose of Aggr. The objective of this study was to assess the responsiveness of animals pretreated with Aggr. to bacterial LPS and vice versa.Female Wistar rats (250-300 g) were used. Each experiment was carried on at least 4 animals.A human IgG preparation containing 30% aggregates (10-16 mg/100 g) or E. coli serotype 0111.B4 (0.005-mg/100 g) was administered i.v. Certain groups of animals were pretreated with 1 mg/100 g GdCl3 or with 10 mg/100 g pentoxyphylline (PTX).Arterial blood pressure was monitored in the carotis-using a polyethylene cannula and an electronic tension meter. Tumor necrosis factor alpha (TNF-alpha) activity was estimated by the use of an L-929 cell cytotoxicity assay.Pretreatment of rats with a sublethal dose of LPS impaired the hypotensive reaction of the animals to Aggr. Rats male "refractory" to Aggr. reacted to the injection of LPS with hypotension and a second phase milder than in the controls. Hypotension could not be elicited by Aggr. in rats pretreated with GdCl3. The same pretreatment had no effect on the first phase of hypotension induced by intravenous injection of LPS, whilst a mitigation of the second phase was observed. Infusion of PTX immediately prior to Aggr. administration prevented the drop of blood pressure. A sizeable level of TNF-alpha was detected only later than blood pressure had reached its minimum level following Aggr. administration.Hypotension induced by LPS may involve a macrophage population broader than that responsible for the vascular action of Aggr. The data presented do not support a primary role for TNF-alpha in Aggr. induced hypotension. |
| 1997 | The involvement of tumour necrosis factor-alpha in the protective effects of 17 beta oestradiol in splanchnic ischaemia-reperfusion injury. | Br J Pharmacol | 1. Tumour necrosis factor-alpha (TNF-alpha) is a cytokine that is implicated in the pathogenesis of ischaemic states and atherosclerosis. We tested the hypothesis that the vasoprotective effects of the oestrogens may be mediated in vivo by inhibition of the formation of TNF-alpha. 2. Anaesthetized rats, subjected to total occlusion of the superior mesenteric artery and the coeliac trunk for 45 min developed a severe shock state resulting in a fatal outcome within 75-90 min after the release of occlusion. Sham-operated animals were used as controls. 3. Splanchnic artery occlusion (SAO) shocked rats had a marked hypotension, enhanced levels of TNF-alpha in serum and macrophages, leukopenia and increased ileal leukocyte accumulation, studied by means of myeloperoxidase activity (MPO). Furthermore, aortae from SAO rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM-10 microM), reduced responsiveness to acetylcholine (ACh, 10 nM-10 microM) and an increased staining for intercellular adhesion molecule-1 (ICAM-1). 4. In vivo administration of 17 beta oestradiol (500 micrograms kg-1, i.m., three hours before the induction of SAO) increased survival rate (100%, 4 h after SAO), enhanced mean arterial blood pressure; reduced serum TNF-alpha (25 +/- 5 u ml-1 vs 379 +/- 16 u ml-1), ameliorated leukopaenia and reduced ileal MPO (0.7 +/- 0.02 u 10(-3) g-1 tissue vs 4.2 +/- 0.4 u 10(-3) g-1 tissue). Furthermore aortae from SAO rats treated with 17 beta oestradiol exhibited a greater contractile response to phenylephrine, improved responsiveness to ACh and a blunted staining of ICAM-1. Finally 17 beta oestradiol, added in vitro to peritoneal macrophages collected from untreated SAO rats, significantly reduced TNF-alpha production. 5. Our results suggest that inhibition of TNF-alpha in vivo may explain, at least in part, the vasoprotective effects of oestrogens. |
| 1997 | Dissociation of TNF-alpha from endotoxin-induced nitric oxide and acute-phase hypotension. | Am J Physiol | We tested the concept that tumor necrosis factor-alpha (TNF-alpha) or platelet-activating factor (PAF) mediated Escherichia coli endotoxin lipopolysaccharide (LPS)-induced upregulation of nitric oxide (NO) and acute-phase hypotension (APH) in the rat. LPS (0.5 mg/kg i.v.) given to rats treated with saline or nonimmune goat-derived gamma-globulin (immunoglobulin G, 22 mg/kg i.m.) produced APH and increased plasma concentrations of TNF-alpha and nitrate and nitrite anions (reactive nitrogen intermediates; RNI) and NO in ex vivo incubates of polymorphonuclear neutrophils (PMN) and inducible NO synthase (iNOS) mRNA in PMN. Pretreatment of rats with a polyclonal TNF-alpha antibody (TNF-Ab, 22 mg/kg i.m.) abolished LPS-mediated increases in plasma TNF-alpha but failed to inhibit APH or the NO system. TNF-alpha (8.2 micrograms/kg i.v.) produced transient hypertension and sustained tachycardia and increased plasma TNF-alpha and PMN iNOS mRNA but not RNI. LPS and TNF-alpha decreased spontaneous and calcimycin (Ca2+ ionophore, 1 microM)- and PAF (1 microM)-mediated increases in head-space NO production by rings of mesenteric artery incubated ex vivo. TNF-Ab abolished all effects of TNF-alpha. PAF (25, 50, and 100 ng/kg) produced APH without increasing plasma TNF-alpha, RNI, or PMN iNOS mRNA. The PAF receptor antagonist BN-50730 (80 micrograms/kg i.v.) abolished PAF-induced APH and attenuated LPS-induced increases in RNI. We conclude that 1) LPS produces parallel but unrelated changes in TNF-alpha and RNI in plasma and PMN during the APH of endotoxemia; and 2) endogenous TNF-alpha is not required for LPS-mediated induction of iNOS mRNA, and PAF mediates LPS-induced APH. |
| 1997 | A matrix metalloproteinase inhibitor prevents processing of tumor necrosis factor alpha (TNF alpha) and abrogates endotoxin-induced lethality. | Shock | Excessive tumor necrosis factor alpha (TNF alpha) production in response to Gram-negative bacteremia or endotoxemia can often lead to hypotension, shock, and increased mortality. Current approaches used to block the deleterious effects of exaggerated TNF alpha production rely on monoclonal antibodies or immunoadhesins that bind TNF alpha and thus prevent the interaction with its cellular receptors. This report examines whether a previously described inhibitor of matrix metalloproteinases, GM-6001, can inhibit TNF alpha processing and release and attenuate endotoxin-induced mortality. In human peripheral blood mononuclear cells stimulated in vitro with 1 microgram/mL endotoxin, GM-6001 at concentrations > 5 micrograms/mL blocked release of TNF alpha, but did not affect the release of either IL-1 beta or IL-6. GM-6001 also inhibited the release of soluble TNF receptor (p75) from peripheral blood mononuclear cells stimulated with endotoxin and/or TNF alpha. To confirm the role of secreted TNF alpha in endotoxic shock-induced mortality, C57BL/6 mice were challenged with either endotoxin alone (500 micrograms/mouse) or endotoxin (100 ng/mouse) plus D-galactosamine (8 mg/mouse). GM-6001 pretreatment (100 mg/kg) significantly attenuated the 90-minute plasma TNF alpha response in both models and improved survival in mice treated with low-dose endotoxin plus D-galactosamine. However, plasma IL-1 beta and IL-6 concentrations at 90 min after endotoxin treatment were unaffected by GM-6001 following lethal endotoxin challenge, confirming the in vivo specificity of this matrix metalloproteinase inhibitor for TNF alpha processing. These findings demonstrate that a novel inhibitor of matrix metalloproteinases can prevent the release of TNF alpha both in vitro and in vivo, and can abrogate the harmful sequelae of endotoxemic shock. |
| 1997 | [The effects of removing circulated TNF by immunoadsorption on renal changes in rabbits with endotoxin shock]. | Zhonghua Yi Xue Za Zhi | To remove circulating tumor necrosis factor (TNF) by specific immunoadsorption column containing anti-TNF monoclonal antibody (McAb) and observe the effects of the therapy on renal changes in experimental endotoxin shock.New Zealand white rabbits were injected with lethal dose of E. coli endotoxin (LPS, 8 x 10(9) cfu/kg) to produce endotoxin shock, then were divided into two groups: control (n = 7) and perfusion group (n = 10). Perfusion was started at 1 hour after administration of endotoxin. Mean arterial pressure (MAP) was monitored continuously. Blood samples were collected for assay of TNF, urea nitrogen (BUN) and creation (Cr). Six hours after infusion of LPS, rabbits were sacrificed, then the kidney was taken for pathologic observation.MAP was increased 30 minutes after perfusion in perfusion group, then kept at a level higher than that in the control group in the monitoring period (P < 0.01). The plasma TNF activation was reduced significantly in the perfusion group (44 +/- 10) compared with the control group (1448 +/- 226, P < 0.05) one hour after perfusion. The levels of BUN and Cr were decreased in the perfusion group compared with the control group. The degree of glomerular congestion and infiltration of leukocytes in glomeruli was significantly lower in the perfusion group than in the control group. The degree of tubular necrosis was decreased significantly in the perfusion group compared to that in the control group (P < 0.05). The mitochondrial ultrastructural changes were more severe in the control group than in the perfusion group.Specific immunoadsorptive column containing anti-TNFMcAb could remove effectively circulating TNF in experimental endotoxin shock. Reducing levels of TNF in the early phase of endotoxin shock may ameliorate the state of hypotension. |
| 1997 | Superantigen-based immunotherapy: a phase I trial of PNU-214565, a monoclonal antibody-staphylococcal enterotoxin A recombinant fusion protein, in advanced pancreatic and colorectal cancer. | J Clin Oncol | To establish the maximum-tolerated dose (MTD) and define the toxicities of a single-dose infusion of PNU-214565, a recombinant Escherichia coli-derived fusion protein of Staphylococcal enterotoxin A (SEA) and the Fab-fragment of the C242 monoclonal antibody in patients with advanced colorectal and pancreatic carcinomas. To investigate the capability of PNU-214565 to induce a superantigen (SAg) response resulting in cytokine production and tumor regression.Twenty-one patients (age range, 39 to 76 years; median, 64; 12 men, nine women; 18 colorectal, three pancreatic cancers) were treated with a single 3-hour infusion of PNU-214565, with doses ranging from 0.01 to 1.5 ng/kg. All patients had prior chemotherapy and a good performance status Eastern Cooperative Oncology Group [ECOG] performance status [PS] = 0 [n = 10]; PS = 1 [n = 11]), 10 had prior radiation, and 18 had prior surgery.Fever and hypotension were the most common toxicities. Fever of any grade occurred in 16 of 21 patients (76%): four of 21 (19%) with grade 2 and two of 21 (9.5%) with grade 3. Hypotension of any grade occurred in 13 of 21 (62%): four of 21 with grade 2 and one of 21 (5%) with grade 3. Interleukin-2 (IL-2) and tumor necrosis factor alpha (TNF alpha) induction correlated with toxicity. In the two patients with grade 3 fever, peak IL-2 and TNF alpha levels were 2.9 IU/mL and 165 pg/mL, and 8.3 IU/mL and 245 pg/mL, respectively. Transient, > or = 50% decreases in circulating monocytes were observed in 17 of 21 patients as early as 0.5 hours (median time, 2 hours) from the start of infusion. Decreases (mean 33%) in circulating lymphocytes were observed in seven of 21 patients. All three patients with grade 3 toxicity were treated at the 0.5-ng/kg dose. The significance of baseline anti-SEA, human antimouse antibody (HAMA), CA242-soluble antigen levels, and T-cell receptor variable beta region (TCR V beta) subsets and histocompatibility leukocyte antigen-DR (HLA-DR) genotypes was assessed as possible predictors of toxicity. All toxicities were transient and easily managed. No grade 3 toxicity occurred at the higher dose levels.PNU-214565, a SAg-based tumor targeted therapy, is safe when given as a single 3-hour infusion at doses up to 1.5 ng/kg. The MTD for a single dose was not determined. The safety of a repeated dose schedule is currently under investigation, beginning with doses determined to be safe in this trial. |
| 1997 | Intervention in endotoxin shock by sulfatide (I3SO3-GalCer) with a concomitant reduction in tumor necrosis factor alpha production. | Infect Immun | Accumulating evidence indicates that tumor necrosis factor alpha (TNF-alpha) is a principal mediator of endotoxin shock. We previously reported that the action as well as the production of TNF requires the adhesion of leukocytes to the endothelium through integrin beta2 and intercellular adhesion molecule 1. In order to elucidate the roles of the initial interaction of the leukocytes with the endothelium through the selectins, we have examined the effects of a ligand for L- and P-selectins, sulfatide, on endotoxin shock in mice. Consistent with previous reports, a single injection of a high dose of endotoxin caused acute lethality, marked hypotension, leukopenia, and elevation in serum TNF-alpha levels. Pretreatment with sulfatide prevented acute lethality and hypotension, but not leukopenia, with a concomitant reduction in the increase in serum TNF-alpha levels. Moreover, pretreatment with sulfatide inhibited lipopolysaccharide (LPS)-induced TNF-alpha production by a human monocytic cell line, THP-1, in a dose-dependent manner. These results suggest either that selectin is critically involved in conferring the responsiveness of leukocytes to LPS or that sulfatide interferes with the intracellular signaling pathway which leads to TNF-alpha gene activation. |
| 1997 | Sympathetic nervous responses during cytokine-induced fever in conscious rabbits. | Pflugers Arch | Sympathetic responses during fever induced by two representative endogenous pyrogens, interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF alpha), and their effective inducer, lipopolysaccharide (LPS), were investigated in conscious rabbits. Rectal temperature, ear skin temperature as an index for the ear skin sympathetic nerve activity (ESNA), renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) were recorded during fever induced by intravenous injection of these pyrogens. IL-1 beta (100 ng/kg) elicited a fever accompanied by a transient activation of ESNA and long-lasting increases in RSNA, MAP and HR. Subcutaneous indomethacin (20 mg/kg) significantly attenuated all the responses induced by IL-1 beta. TNF alpha (10 micrograms/kg) also elicited fever with increases in ESNA, RSNA and HR, while MAP was not affected. All the TNF-induced responses were totally blocked by indomethacin. LPS at two doses of 500 ng/kg and 1 microgram/kg elicited fever and increased ESNA, RSNA and HR. Only the larger dose induced hypotension. The present results show in conscious rabbits exposed to thermoneutral environment that these pyrogens activate sympathetic efferents in regionally differentiated time courses. The present results also suggest that arachidonate metabolites are involved not only in the thermoregulatory vasoconstrictor response in the ear and the body temperature increase but also in simultaneously evoked renal sympathetic and haemodynamic adjustments in fever. |
| 1997 | The effects of post-treatment with lisofylline, a phosphatidic acid generation inhibitor, on sepsis-induced acute lung injury in pigs. | Am J Respir Crit Care Med | The effects of lisofylline [(R)-1-(5-hydroxyhexyl)-3,7-dimethylxanthine] (LSF), an inhibitor of de novo phosphatidic acid (PA) generation, on sepsis-induced acute lung injury was studied using Hanford minipigs weighing 18 to 25 kg. Sepsis was induced by an intravenous infusion of Pseudomonas aeruginosa (1 x 10(6)/colony-forming units/kg/min over 2 h). Saline was used as the control vehicle. Six groups were studied: saline control group (SALINE: n = 5); sepsis control group (SEPSIS: n = 5); LSF control group (LSF: n = 5), which received a 25-mg/kgbolus of LSF 30 min before time zero followed by continuous infusion of 10 mg/kg/h throughout the study; LSF-treated septic groups, which were treated with LSF 30 min prior to sepsis (Pre: n = 5), 1 h postonset (Post-1 h: n = 8) or h postonset (Post-2 h: n = 8) of the bacterial infusion. Hemodynamics PaO2, neutrophil counts, and plasma porcine tumor necrosis factor-alpha concentrations were monitored for 6 h. After the minipigs were killed, lung tissue was sampled to measured wet-to-dry weight ratio (W/D), tissue albumin index (TAI), thiobarbituric acid-reactive material content (TBARM), and myeloperoxidase (MPO) activity. Compared with the SALINE group, the SEPSIS group showed significant systemic hypotension, pulmonary hypertension, arterial hypoxemia, neutropenia, and increase in TNF-alpha, MPO activity, W/D, TBARM, and TAI. LSF treatment attenuated sepsis-induced pulmonary hypertension, neutropenia, and hypoxemia, and increased MPO activity and lung injury measurements in the Pre and Post-1 h groups, but its efficacy was blunted in the Post-2 h group. Plasma TNF-alpha was decreased only in the Pre group. Thus, inhibition of intracellular PA generation through de novo pathways attenuates sepsis-induced acute lung injury. |
| 1997 | Renal function in cancer patients treated with hyperthermic isolated limb perfusion with recombinant tumor necrosis factor-alpha and melphalan. | Nephron | Hyperthermic isolated limb perfusion (HILP) with recombinant tumor necrosis factor-alpha (r-TNF alpha) and melphalan has been shown to result in a sepsis-like syndrome due to leakage of r-TNF alpha from the perfusion system to the systemic circulation. We have studied renal function parameters in 11 cancer patients, who underwent 12 perfusions. Three patients, perfused with melphalan only, served as controls. All patients treated with r-TNF alpha developed a sepsis syndrome and needed volume replacement and inotropes to remain normotensive; controls had an uneventful postoperative course. Creatinine clearance decreased transiently on the day of perfusion in both groups (mean preperfusion clearance 118 ml/min, mean post-perfusion clearance 68 ml/min, p < 0.02, n = 15). Follow-up measurements of renal plasma flow and glomerular filtration rate in 9 r-TNF alpha-treated patients did not suggest permanent damage. One patient became hypotensive and developed transient multiple organ dysfunction with renal failure needing hemofiltration. In r-TNF alpha-treated patients, but not in controls, a transient increase in clearance of beta2-microglobulin (0.05 vs. 8 ml/min, p < 0.001) and urinary excretion of phosphate (12 vs. 48 mmol/l, p < 0.05) was seen, compatible with proximal tubular dysfunction. These data suggest that HILP with melphalan decreases glomerular function, whether or not r-TNF alpha is added to the perfusion circuit. Extension of the treatment regimen with r-TNF alpha may result in additional proximal tubular dysfunction. If hypotension can be avoided, this deterioration in renal function seems to be transient, with full recovery within weeks. |
| 1997 | Cytokine mRNA expression after transient and prolonged hypotension. | Surg Today | The role of cytokines in hemorrhagic shock remains controversial, with some studies showing an elevation of cytokines, whereas others do not. We thus analyzed the changes in tumor necrosis factor (TNF) activity and in mRNA of TNF alpha, interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) after transient and prolonged hypotension. In the transient hypotension group (TH group), chronically cannulated rats were bled (20 ml/kg x 3 min) without fluid resuscitation. They showed transient hypotension, but their blood pressure (BP) quickly stabilized. In the prolonged hypotension group (PH group), the rats were bled and maintained at a mean BP of 40 mmHg for 60 min, and then were resuscitated with the shed blood and an equal volume of saline over 60 min. The serum TNF activity was measured by cytotoxicity against the L929 tumorigenic murine fibroblast. Messenger RNA of TNF alpha, IL-1beta, and IL-6 in liver was measured semi-quantitatively by high-performance liquid chromatography after reverse transcription and polymerase chain reaction. The increases in the TNF activity were not significant in either of the groups above the prehemorrhage levels, whereas mRNA of TNF alpha and IL-1beta showed a transient elevation in the TH group and a persistent elevation in the PH group. IL-6 mRNA did not increase significantly in the TH group, but did increase in the PH group. These results show that a large hemorrhage induces cytokine mRNA in the liver and also show the differences in the changes of cytokine mRNA after transient and prolonged hypotension. |
| 1996 | Role of nitric oxide in the circulatory failure and organ injury in a rodent model of gram-positive shock. | Br J Pharmacol | 1. The pathological features of Gram-positive shock can be mimicked by the co-administration of two cell wall components of Staphylococcus aureus, namely lipoteichoic acid (LTA) and peptidoglycan (PepG). This is associated with the expression of the inducible isoform of nitric oxide synthase (iNOS) in various organs. We have investigated the effects of dexamethasone (which prevents the expression of iNOS protein) or aminoguanidine (an inhibitor of iNOS activity) on haemodynamics, multiple organ dysfunction syndrome (MODS) as well as iNOS activity elicited by LTA + PepG in anaesthetized rats. 2. Co-administration of LTA (3 mg kg-1, i.v.) and PepG (10 mg kg-1, i.v.) resulted in a significant increase in the plasma levels of tumour necrosis factor-alpha (TNF alpha, maximum at 90 min) as well as a biphasic fall in mean arterial blood pressure (MAP) from 120 +/- 3 mmHg (time 0) to 77 +/- 5 mmHg (at 6 h, n = 8; P < 0.05). This hypotension was associated with a significant tachycardia (4-6 h, P < 0.05) and a reduction of the pressor response elicited by noradrenaline (NA, 1 microgram kg-1, i.v., at 1-6 h; n = 8, P < 0.05). Furthermore, LTA + PepG caused time-dependent increases in the serum levels of markers of hepatocellular injury, glutamate-pyruvate-transminase (GPT) and glutamate-oxalacetate-transaminase (GOT). In addition, urea and creatinine (indicators of renal dysfunction) were increased. There was also a fall in arterial oxygen tension (PaO2), indicating respiratory dysfunction, and metabolic acidosis as shown by the significant drop in pH, PaCO2 and HCO3-. These effects caused by LTA + PepG were associated with the induction of iNOS activity in aorta, liver, kidney and lungs as well as increases in serum levels of nitrite+nitrate (total nitrite). 3. Pretreatment of rats with dexamethasone (3 mg kg-1, i.p.) at 120 min before LTA + PepG administration significantly attenuated these adverse effects as well as the increases in the plasma levels of TNF alpha caused by LTA + PepG. The protective effects of dexamethasone were associated with a prevention of the increase in iNOS activity (in aorta, liver, lung, kidney), the expression of iNOS protein (in lungs), as well as in the increase in the plasma levels of total nitrite. 4. Treatment of rats with aminoguanidine (5 mg kg-1 + 10 mg kg-1 h-1) starting at 120 min after LTA + PepG attenuated most of the adverse effects and gave a significant inhibition of iNOS activity (in various organs) as well as an inhibition of the increase in total plasma nitrite. However, aminoguanidine did not improve renal function although this agent caused a substantial inhibition of NOS activity in the kidney. 5. Thus, an enhanced formation of NO by iNOS importantly contributes to the circulatory failure, hepatocellular injury, respiratory dysfunction and the metabolic acidosis, but not the renal failure, caused by LTA + PepG in the anaesthetized rat. |
| 1996 | Evidence for inducible nitric oxide synthase in spontaneously hypertensive rats. | Biochem Biophys Res Commun | This study investigates the mechanism of the production of nitric oxide (NO) caused by lipopolysaccharide (LPS) in spontaneously hypertensive rats (SHR) or Wistar-Kyoto (WKY) rats. The injection of LPS (5 mg/ kg, i.v.) caused a mild hypotension in WKY rats, while it induced a more severe hypotensive effect in SHR. The basal level of plasma nitrite was slightly higher in SHR than in WKY rats. At 3 h after injection of LPS, the increment in plasma nitrite was more significant in SHR. Prior to the treatment of rats with LPS, the plasma level of tumor necrosis factor-alpha (TNF alpha) was also higher in SHR than in WKY rats, and LPS induced a more significant increase of TNF alpha level (at 1 h) in SHR. In rats treated with LPS, acetylcholine-induced relaxation was significantly impaired in thoracic aortic rings obtained from WKY rats, but not in those from SHR. By contrast, L-arginine (1 mM) did not cause any relaxations in rings without the endothelium obtained from WKY rats while it slightly relaxed those from SHR, and this difference was further augmented by treatment of rats with LPS for 3 h. In addition, the basal cGMP level was higher in SHR, which was inhibited by aminoguanidine (AG, 1 mM). The treatment of rats with LPS further increased the formation of cGMP in both strains and this increment was greater in SHR than in WKY rats, which was also attenuated by AG to a similar level between both strains. Interestingly, an expression of inducible NO synthase (NOS II) protein was only observed in SHR, and further enhanced by treated rats with LPS. We conclude that an increased production of NO in SHR, which was further enhanced by LPS, is attributed to a basal expression of NOS II. |
| 1996 | Role of nitric oxide in recombinant tumor necrosis factor-alpha-induced circulatory shock: a study in patients treated for cancer with isolated limb perfusion. | Crit Care Med | To analyze the mechanism of vasodilation and circulatory shock occurring in patients who are treated with isolated limb perfusion with melphalan and recombinant tumor necrosis factor (TNF)-alpha for locally advanced malignant tumors. To determine the role of nitric oxide, if any, by measuring plasma nitrite and nitrate concentrations.Observational survey.A 12-bed surgical intensive care unit in a university referral hospital.Eight patients treated with hyperthermic isolated limb perfusion.Ninety minutes of hyperthermic isolated limb perfusion with recombinant TNF-alpha (3 or 4 mg) and melphalan (10 to 13 mg/L limb volume).All patients developed sepsis syndrome due to leakage of recombinant TNF-alpha from the perfusion circuit to the systemic circulation. Despite the presence of very high systemic TNF-alpha concentrations during and immediately after perfusion, and despite definite signs of hyperdynamic circulatory shock (increased heart rate, increased cardiac index, decreased systemic vascular resistance), nitrite and nitrate concentrations, as measured in plasma at several time points, were not increased.The hypothesis that in humans, TNF-alpha induces vasodilation and shock through activation of inducible nitric-oxide synthase and subsequent formation of excessive quantities of nitric oxide is not substantiated by our results. Normal nitric oxide metabolite concentrations were found in the presence of high TNF-alpha concentrations and shock. Other mechanisms that do not involve the nitric oxide pathway are likely to play a role in the generation of hypotension and septic shock in this setting. |
| 1996 | [Isolated limb perfusion with tumor necrosis factor for malignancies of the limbs]. | Harefuah | Tumor necrosis factor (TNF) induces rapid necrosis in a variety of experimental neoplasms. However, its clinical application is limited by life-threatening systemic toxicity. Isolated limb perfusion (ILP) enables administration of large doses of TNF and cytotoxic drugs directly to the affected limb, avoiding systemic toxicity. We describe our experience in 20 consecutive patients (10 with melanoma and 10 with soft tissue sarcoma) treated with high-dose TNF and melphalan via ILP. ILP was performed via the external iliac (10 cases), femoral (2), popliteal (5) or brachial (3) vessels. Patients received 3-4 mg TNF to an upper, and 1-1.5 mg/kg to a lower extremity. Isolation efficiency was determined by injection of radiolabelled albumin. The procedure was successful in all 20 patients. Local complications included wound infection in 6 cases and hematoma in 2. 1 patient developed sepsis secondary to extensive necrosis of a large, secondarily infected tumor. The first 6 patients who underwent high-flow perfusion experienced systemic side-effects, mainly hypotension. These side-effects were eliminated when low-flow perfusion was introduced. The response rate was 100%. In the sarcoma group, 5/10 had complete response, and 5 partial response. Amputation or mutilating surgery was avoided in 9/10. Of the 10 with melanoma, 7 had complete, and 3 partial response. We conclude that administration of TNF via ILP is a safe and effective modality for treating advanced neoplasms of the limbs. |
| 1996 | Ethanol suppresses endotoxin but not platelet activating factor-induced hypotension and nitric oxide. | Alcohol Clin Exp Res | Ethanol (ETOH) inhibits the immune response to endotoxemia. The early stage of endotoxin (LPS)-induced shock is associated with an acute phase cardiovascular depression (APCD). Release of platelet activating factor (PAF) and tumor necrosis factor alpha (TNF alpha) with upregulation of nitric oxide (NO) production may initiate the APCD. Since ETOH inhibits induction of NO synthase (iNOS) mNRA by LPS, we postulate that ETOH may mask the APCD associated with endotoxemia. To test this, Sprague-Dawley rats (280-320 g, n = 5-6/group) were given LPS [0.75 mg/kg, intravenously (i.v.)] or PAF (10 to 150 micrograms/kg, i.v.) 30 min after administration of sterile saline (PBS), BN-5073 a mixed PAF antagonist (0.50 microgram/kg, i.v.), or ETOH [2.2-5.5 g/kg, intraperitoneally (i.p.)]. Cardiovascular parameters and plasma concentrations of nitrate and nitrite (RNI), ETOH, TNF alpha, and neutrophil (PMN) generation of RNI were measured. LPS and PAF both produced APCD. LPS-induced APCD was associated with tachycardia, elevated plasma TNF alpha and RNI, and ex vivo generation of RNI by PMNs. ETOH and BN-50730 prevented LPS-induced APCD and increases in RNI and TNF alpha. ETOH, however, increased the mortality associated with APCD. PAF produced only hypotension, bradycardia and elevated plasma levels of TNF alpha. ETOH and LNMMA did not affect PAF-induced APCD. BN-50730 inhibited PAF-induced APCD and plasma TNF alpha. We conclude that 1) ETOH inhibits the APCD and induction of NO characteristic of endotoxemia and 2) ETOH-induced suppression of LPS-mediated APCD may be mediated in part by suppression of release of intracellular PAF. Ethanol may increase the morbidity and mortality of endotoxemia by masking the hypotension and humoral changes characteristic of early endotoxemia thereby delaying appropriate therapy and by diminution of the protective effects of endogenous NO. |
| 1996 | Antibodies against CD14 protect primates from endotoxin-induced shock. | J Clin Invest | Lipopolysaccharide (LPS), residing in the outer membrane of all gram-negative bacteria, is considered a major initiating factor of the gram-negative septic shock syndrome in humans. LPS forms a complex with the LPS binding protein (LBP) in plasma, and LPS-LBP complexes engage a specific receptor, CD14, on the surface of myeloid cells, leading to the production of potent proinflammatory cytokines. The major goal of this study was to test the importance of the CD14 pathway in vivo in a primate model that is similar to human septic shock. Primates were pretreated with one of two different inhibitory anti-CD14 mAbs, then challenged with intravenous endotoxin (375 microg/kg/h) for 8 h. The anti-CD14 treatment regimens were successful in preventing profound hypotension, reducing plasma cytokine levels (TNF-alpha, IL-1beta, IL-6, and IL-8), and inhibiting the alteration in lung epithelial permeability that occurred in animals treated with LPS and an isotype-matched control antibody. These results demonstrate for the first time the importance of the CD14 pathway in a primate model that is similar to human septic shock. Inhibition of the CD14 pathway represents a novel therapeutic approach to treating this life-threatening condition. |
| 1996 | Phase II trial of intravenous endotoxin in patients with colorectal and non-small cell lung cancer. | Eur J Cancer | We report the immunological and clinical results of a phase II trial with intravenously administered highly purified endotoxin (Salmonella abortus equi) in patients with advanced cancer. 15 patients with non-small cell lung cancer and 27 with colorectal cancer were entered into the study. 37 evaluable patients received at least four injections of endotoxin (4 ng/kg body weight) and 1600 mg ibuprofen orally in 2-week intervals. Transient renal (WHO grade 0-1) and hepatic (WHO grade 0-4) toxicities occurred in several patients. Constitutional side-effects such as fever, chills and hypotension could not be prevented completely by pretreatment with ibuprofen. 3 patients in the colorectal cancer group demonstrated objective responses (1 complete remission (CR), 2 partial remission (PR)). The complete remission has been maintained for more than 3 years, while the partial remissions were stable for 7 and 8 months, respectively. Only marginal antitumour effects were seen in the lung cancer group. Tolerance of the macrophage system to the stimulatory effect of endotoxin, as measured by human necrosis factor alpha (TNF-alpha) release into serum, built up after the first administration and remained at a steady-state level after each subsequent injection. In constrast, rising CD4:CD8 ratio and release of tumour necrosis factor beta (TNF-beta) indicated the continuing activation of the lymphocyte system by repetitive injections of endotoxin. |
| Increased production of nitric oxide in patients with hemorrhagic fever with renal syndrome--relation to arterial hypotension and tumor necrosis factor. | Infection | In 15 consecutive subjects hospitalized with nephropathia epidemica, a European form of hemorrhagic fever with renal syndrome, the plasma concentrations of nitrate plus nitrite, stable metabolites of nitric oxide, were determined. From day 3 of onset of disease the concentrations increased, peak levels being reached on days 5 to 7. Maximal plasma concentrations of nitrate plus nitrite were correlated to the degree of hypotension (r = -0.64, p = 0.02) and levels of tumor necrosis factor (TNF)-alpha (r = 0.51, p = 0.05) and soluble TNF receptors p55 and p75 (r = 0.58, p = 0.03 and r = 0.54, p = 0.04, respectively) but not to levels of interferon-gamma or interleukin-10 (p > 0.05). The results are compatible with the well-known capacity of TNF-alpha to enhance production of nitric oxide, and suggest that nitric oxide may be of physiologic importance in hemorrhagic fever with renal syndrome. |
| Protective effect of NG-monomethyl-L-arginine against hypotension inducted by combined tumour necrosis factor-alpha and whole body hyperthermia in rats. | Int J Hyperthermia | We studied: (a) the adverse effects of tumour necrosis factor-alpha (TNF) given during whole body hyperthermia (WBH) on mean arterial pressure (MAP) and gut mucosa in anaesthetized rats; (b) the potential protective effect of NG-monomethyl-L-arginine (L-NMA), an inhibitor of nitric oxide synthase; and (c) the influence of L-NMA on the antitumour effect of the trimodality therapy, WBH + TNF + Carboplatin (CBDCA). In normothermic rats, TNF alone (10(5) or 10(6) U/kg) did not cause hypotension, but increased MAP (p < 0.05). L-NMA alone (5, 10 and 20 mg/kg) increased MAP moderately and dose-dependently (p < 0.05). WBH (41.5 degrees C for 2 h) increased MAP markedly (from 103 +/- 4 to 161 +/- 4 mm Hg). This increase in MAP was sustained throughout the hyperthermia, but was followed by a transient relative hypotension (MAP = 80 +/- mm Hg) on cessation of WBH and an eventual return to near baseline at 30 min post-WBH (MAP = 94 +/- 5 mm Hg). WBH + TNF (10(5) or 10(6) U/kg) initially increased MAP similarly to WBH alone. During the second hour of WBH, however, MAP decreased towards pre-treatment levels, and cessation of WBH was followed by sustained hypotension. This late hypotensive state was associated with a mortality during the early (first 2 h) post-WBH period of 17 and 100% at TNF dose of 10(5) and 10(6) U/kg TNF, respectively. L-NMA given to rats receiving WBH + TNF (10(6) U/kg) maintained MAP at levels similar to WBH alone during WBH treatment. L-NMA prevented the post-WBH hypotension, and extended the survival beyond the early (first 2 h) post-WBH period. No rat, however, receiving high dose TNF (10(6) U/kg) survived more than 12 h even with L-NMA (totally 40 mg/kg). WBH + TNF (10(5) and 10(6) U/kg) also produced marked histopathological injury to the gut mucosa at 2 h post-treatment. L-NMA substantially protected the gut from this injury. In rats bearing a transplantable fibrosarcoma, L-NMA did not decrease the antitumour effect consisting of WBH + TNF (10(5) U/kg) + CBDCA, while it decreased (p < 0.05) the general toxicity (weight loss, diarrhea and foot oedema) of this combination. We conclude that L-NMA may prevent or ameliorate the early toxicity but not the late lethal effects of WBH + high dose TNF (10(6) U/kg). Additionally, L-NMA reduces some of the toxicity of WBH + TNF (10(5) U/kg) + CBDCA without decreasing the antitumour effect of this trimodality therapy. Inhibitors of nitric oxide synthase such as L-NMA may provide a novel approach to overcoming the toxicity of TNF in combination with WBH. |
| 1996 | Monocytes and lymphocytes as active participants in the pathogenesis of experimental shock. | Inflamm Res | We investigated the role played by monocytes and lymphocytes in the pathogenesis of experimental shock. Splanchnic artery occlusion (SAO) shock was induced in anaesthetized rats by clamping splanchnic arteries for 45 min followed by reperfusion. Sham operated animals were used as controls. SAO shocked rats had a decreased survival time (80 +/- 11 min, while sham shocked rats survived more than 4 h), increased serum (248 +/- 21 U/ml) and macrophage (145 +/- 15 U/ml) levels of TNF-alpha, enhanced myeloperoxidase (MPO) activity in the ileum (3.38 +/- 0.2 U x 10(-3)/g tissue), decreased number of monocytes, lymphocytes and neutrophils and a profound hypotension. In addition we found an increased expression of vascular cell adhesion molecule-1 (VCAM-1) on aortic endothelium and a reduced percentage of VLA-4 positive monocytes and lymphocytes. Inhibition of TNF-alpha synthesis, reversed the increased endothelial expression of VCAM-1, increased the percentage of integrin VLA-4 positive leukocytes and improved monocyte, lymphocyte and neutrophil count. Furthermore a passive immunization with specific antibodies raised against VCAM-1 (2 mg/kg, i.v. 3 h before SAO) increased survival, reduced MPO activity in the ileum (0.034 +/- 0.04 U x 10(-3)/g tissue) and improved mean arterial blood pressure. Our data suggest that monocytes and lymphocytes participate in the pathogenesis of splanchnic ischaemia-reperfusion injury and may amplify the adhesion of neutrophils to peripheral tissues. |
| 1996 | Platelet activating factor mediates cardiopulmonary dysfunction during graded bacteremic shock. | J Trauma | To determine whether or not platelet activating factor (PAF) is a necessary mediator of cardiovascular dysfunction during graded bacteremia, and to identify PAF interactions with eicosanoids and tumor necrosis factor-alpha (TNF-alpha).Seventeen anesthetized, hemodynamically monitored adult swine were studied for 4 hours in three groups. Group 1 (ANES, n = 5) were anesthesia controls; group 2 (septic control, SC, n = 6) received intravenous Aeromonas hydrophila (109/mL) at rates incrementally increased from 0.2 to 4.0 mL/ kg/h; group 3 (WEB, n = 6) received the PAF receptor antagonist WEB 2086, 3.0 mg/kg intravenously, then A. hydrophila. Cardiopulmonary parameters and plasma thromboxane B2 (TXB2), prostaglandin 6-keto F1 alpha (PGI2), leukotriene B4 (LTB4), leukotrienes C4D4E4 (LTC4D4E4), and TNF-alpha were measured hourly. Statistical analysis was carried out using two-way analysis of variance (ANOVA) for repeated measurements, Dunnett's t test, and Student's t test, where appropriate. Statistical significance was determined at the 95% confidence interval. Values are presented as the mean +/- SEM.Pulmonary arterial pressure, pulmonary capillary wedge pressure, central venous pressure heart rate, VO2 and O2ER decreased significantly after WEB 2086 infusion, compared with SC, and mean arterial pressure, systemic vascular resistance index, stroke volume index, and left ventricular stroke work index increased. Arterial pH decreased significantly in SC animals, but was maintained at normal levels during bacteremia in the WEB group. Differences between WEB and SC for cardiac index, pulmonary vascular resistance index, right ventricular stroke work index, PaO2, SaO2, and PcO2, were not significant. The addition of WEB 2086 significantly decreased plasma levels of TXB2, PGI2, LTB4, and TNF-alpha compared with the SC group. LTC4D4E4 was decreased in WEB compared with SC animals, in which LTC4D4E4 increased during graded bacteremia.PAF is necessary to the development of systemic vasodilation and hypotension, pulmonary hypertension, decreased stroke volume, metabolic acidosis, and increased oxygen uptake during graded bacteremia. PAF-induced eicosanoid and cytokine release may be involved. |
| 1996 | Prevention of Jarisch-Herxheimer reactions by treatment with antibodies against tumor necrosis factor alpha. | N Engl J Med | In patients with louse-borne relapsing fever (Borrelia recurrentis infection), antimicrobial treatment is often followed by sudden fever, rigors, and persistent hypotension (Jarisch-Herxheimer reactions) that are associated with increases in plasma concentrations of tumor necrosis factor alpha (TNF-alpha), interleukin-6, and interleukin-8. We attempted to determine whether sheep polyclonal Fab antibody fragments against TNF-alpha (anti-TNF-alpha Fab) could suppress the Jarisch-Herxheimer reaction.We conducted a randomized, double-blind, placebo-controlled trial in 49 patients with proven louse-borne relapsing fever. Immediately before the intramuscular injection of penicillin, the patients received an intravenous infusion of either anti-TNF-alpha Fab or a control solution.Ten of the 20 patients given anti-TNF-alpha Fab had Jarisch-Herxheimer reactions with rigors, as compared with 26 of the 29 control patients (P = 0.006). The controls had significantly greater mean maximal increases in temperature (1.5 vs. 0.8 degrees C, P < 0.001), pulse rate (31 vs. 13 per minute, P < 0.001), and systolic blood pressure (25 vs. 15 mm Hg, P < 0.003), as well as higher mean peak plasma concentrations of interleukin-6 (50 vs. 17 micrograms per liter) and interleukin-8 (2000 vs 205 ng per liter) (P < 0.001 for both comparisons). Levels of TNF-alpha were undetectable after treatment with anti-TNF-alpha Fab.Pretreatment with sheep anti-TNF-alpha Fab suppresses Jarisch-Herxheimer reactions that occur after penicillin treatment for louse-borne relapsing fever, reduces the associated increases in plasma concentrations of interleukin-6 and interleukin-8, and may be useful in other forms of sepsis. |
| 1996 | Prevention of cytokine-induced hypotension in cancer patients by the pineal hormone melatonin. | Support Care Cancer | Hypotension is a frequent side-effect of cancer biotherapies with cytokines. Cytokine-induced hypotension would mainly depend on the stimulation of nitric oxide (NO) production, which represents the most effective endogenous vasodilator. Moreover, it has been proven that both biological activity and toxicity of cytokines are influenced by the psychoneuroendocrine system, in particular by the pineal hormone melatonin. To investigate the possible modulatory effect of melatonin on cytokine cardiovascular toxicity, we evaluated the influence of a concomitant melatonin administration on interleukin-2(IL-2)- and tumour-necrosis-factor-alpha(TNF)-induced hypotension in advanced cancer patients. The study included 116 patients with advanced solid tumour, for whom no effective standard anticancer therapy was available, who underwent cancer biotherapy with IL-2 (3 x 10(6) IU/ day s.c. every day, 6 days/week for 4 weeks) or with TNF (0.75 mg/day i.v. for 5 days) as compassionate treatment for their disease. Patients were randomized to be treated with or without a concomitant melatonin administration (40 mg/day orally in the evening, starting 7 days prior to cytokine injection). The occurrence of hypotension was significantly less frequent in patients concomitantly treated by melatonin than in those who received the cytokine alone, during either IL-2: or TNF immunotherapy (IL-2; 11/45 versus 2/46, P < 0.05; TNF: 10/23 versus 1/12, P < 0.01). This study shows that melatonin may prevent hypotension occurring during cancer immunotherapy with IL-2 or TNF. Since the pineal hormone has appeared to inhibit the activity of NO synthase from the endothelial cells, we suggest that melatonin may prevent cytokine-induced hypotension by inhibiting NO production, which plays an essential role in inducing hypotension during IL-2 and TNF biotherapies. |
| 1996 | A human tumor necrosis factor p75 receptor agonist stimulates in vitro T cell proliferation but does not produce inflammation or shock in the baboon. | J Exp Med | Tumor necrosis factor (TNF) is a potentially useful adjunct to anticancer therapies. However, the clinical utility of TNF has been limited by generalized toxicity and hypotension. Recently, studies have begun to dissect the individual proinflammatory and immunologic responses that result from TNF binding to its two cellular receptors, p55 and p75, in an attempt to develop TNF receptor agonists with reduced systemic toxicity. To evaluate a p75 receptor selective TNF mutant (p75TNF), TNF and p75TNF were administered to healthy anesthetized baboons. Intravenous infusion of the p75TNF produced none of the hemodynamic changes seen after the infusion of TNF. Infusion of p75TNF also failed to induce the plasma appearance of interleukins 6 and 8. However, p75TNF enhanced in vitro baboon thymocyte proliferation to concanavalin A, and infusion of p75TNF resulted in increased soluble p55 and p75 receptor plasma concentrations. Local skin necrosis and tissue neutrophil infiltration were seen after subcutaneous injections of TNF and p55TNF. Subcutaneous injection of p75TNF did not result in skin necrosis but did result in a modest dermal infiltration of lymphocytes and macrophages. The findings suggest that p75TNF may stimulate T cell proliferation without the systemic and local toxicity seen with TNF. |
| 1996 | Efficacy of treatment with the iron (III) complex of diethylenetriamine pentaacetic acid in mice and primates inoculated with live lethal dose 100 Escherichia coli. | J Clin Invest | The iron (III) complex of diethylenetriamine pentaacetic acid (DTPA iron [III]) protected mice and baboons from the lethal effects of an infusion with live LD100 Escherichia coli. In mice, optimal results were obtained when DTPA iron (III) was administered two or more hours after infection. Prevention of death occurred in spite of the fact that the adverse effects of TNF-alpha were well underway in the mouse model. The half-life of DTPA iron (III) was 51 +/- 9 min in normal baboons; primary clearance was consistent with glomerular filtration. In septic baboons, survival was observed after administration of two doses of DTPA iron (III) at 2.125 mg/kg, the first one given before, or as late as 2 h after, severe hypotension. Administration of DTPA iron (III) did not alter mean systemic arterial pressure, but did protect baboons in the presence of high levels of TNF-alpha and free radical overproduction. Furthermore, exaggerated production of nitric oxide was attenuated. The mechanism of protection with DTPA iron (III) is not obvious. Because of its ability to interact in vitro with free radicals, its poor cell permeability, and its short half-life, we postulate that DTPA iron (III) and/or its reduced form may have protected the mice and baboons by sequestration and subsequent elimination of free radicals (including nitric oxide) from their systems. |
| 1996 | High-dose recombinant endotoxin neutralizing protein improves survival in rabbits, with Escherichia coli sepsis. | Crit Care Med | To assess the benefit of a recombinant endotoxin neutralizing protein from Limulus polyphemus in treating Gram-negative bacterial sepsis in rabbits.Prospective, blinded, controlled, laboratory trial.Animal research laboratory.New Zealand White rabbits.We established a rabbit model of Escherichia coli peritonitis and bacteremia, with high mortality rate, despite treatment with gentamicin and ceftriaxone. Twenty-five pairs of male New Zealand White rabbits were challenged intraperitoneally with E. coli O18ac K1 in 5% porcine mucin (mean 7 x 10(1) colony-forming units). All animals were treated with intravenous gentamicin (2.5 mg/kg) and ceftriaxone (100 mg/kg), and with either intravenous endotoxin neutralizing protein (50 mg/kg) or saline 1 hr after E. coli challenge.All animals were bacteremic 1 hr after challenge (mean 3.6 x 10(5) colony-forming units/mL). Animals in both groups developed tachycardia, hypotension, and acidosis (NS). Geometric mean serum endotoxin and tumor necrosis factor (TNF) concentrations were significantly ( p < .001) higher 1 hr after challenge compared with baseline prechallenge concentrations in both groups. From 1 to 2 hrs after challenge, endotoxin concentrations increased 2.5-fold in control animals (95% confidence interval = 13.1 to 32.9 endotoxin units/mL, p = .024), whereas endotoxin concentrations increased only 1.2-fold in endotoxin neutralizing protein-treated animals (95% confidence interval = 20.4 to 23.6 endotoxin units/mL, NS). TNF concentrations increased significantly (p < .001) in both groups from 1 to 2 hrs after challenge. Eighteen (72%) of 25 endotoxin neutralizing protein-treated animals vs. 11 (44%) of 25 controls survived 24 hrs (p = .032).Treatment with endotoxin neutralizing protein had the following effects: a) the increase in serum endotoxin was blunted, but not TNF concentrations measured 1 hr after antibiotic treatment; and b) survival in rabbits with E. Coli sepsis was improved. |
| 1996 | Thalidomide inhibits tumor necrosis factor alpha, decreases nitric oxide synthesis, and ameliorates the hyperdynamic circulatory syndrome in portal-hypertensive rats. | Hepatology | A hyperdynamic circulatory state frequently is observed in portal hypertension with liver failure or extensive portal-systemic shunting. Tumor necrosis factor alpha (TNF) causes marked hypotension in mammals by inducing nitric oxide synthesis and has been shown to play a role in the development of the hemodynamic changes observed in portal hypertension. Thalidomide selectively inhibits TNF production by enhancing messenger RNA degradation. We investigated the systemic and portal hemodynamic effects of thalidomide in a prehepatic model of portal hypertension and evaluated whether suppressing TNF synthesis decreases NO production. Portal hypertension was induced by partial ligation of the portal vein (PVL). Animals received thalidomide (T) (50 mg/kg/d) + water or water alone (W), orally, daily for 2 days before and 13 days after PVL operation, at which time hemodynamic studies were performed and TNF plasma levels were obtained. Sham-operated animals were studied identically. In an additional group of PVL animals, 24-hour urinary excretion of NO2- and NO3- was measured during treatment. PVL animals receiving T presented with a significantly higher mean arterial pressure and systemic vascular resistance and significantly lower portal pressure, TNF plasma levels, and 24-hour urinary excretion of NO2- and NO3-, in comparison with rats receiving W. A significant correlation (r = -0.61) was observed between TNF plasma levels and mean arterial pressure among PVL animals. Thalidomide did not have any significant effects on sham rats. Thalidomide inhibits TNF synthesis and reduces NO production, blunts the development of the hyperdynamic circulation, and decreases portal pressure in PVL-operated rats. |
| 1996 | Effects of the endothelin receptor antagonist, SB 209670, on circulatory failure and organ injury in endotoxic shock in the anaesthetized rat. | Br J Pharmacol | 1. This study investigates the effects of the non-selective ETA/ETB receptor antagonist, SB 209670, on systemic haemodynamics, renal function, liver function, acid-base balance and survival in a rat model of endotoxic shock. 2. Injection of E. coli lipopolysaccharide (LPS, 10 mg kg-1, i.v.) resulted in increases in the serum levels of tumour necrosis factor-alpha (TNF-alpha, maximum 60 min after LPS), endothelin-1, (ET-1; maximum 120 min after LPS), and interferon-gamma (IFN-gamma, maximum 180 min after LPS). 3. Injection of LPS also resulted in a fall in blood pressure from 113 +/- 3 mmHg (time = 0) to 84 +/- 4 mmHg at 360 min (n = 15) as well as a hyporeactivity to the vasoconstrictor responses elicited by noradrenaline (NA, 1 microgram kg-1, i.v.). Pretreatment of rats with a continuous infusion of SB 209670 (3 mg kg-1, i.v. bolus + 100 micrograms kg-1, i.v. infusion commencing 15 min prior to LPS) significantly augmented the hypotension as well as the vascular hyporeactivity to NA caused by endotoxaemia. 4. Pretreatment of LPS-rats with SB 209670 (3 mg kg-1, i.v. bolus given 15 min prior to LPS) or infusion of SB 209670 (bolus dose and infusion as above) resulted in a reduction in 6 h-survival from 71% (control) to 30% and 13%, respectively. 5. Endotoxaemia for 4 h resulted in rises in the serum levels of urea and creatinine (indicators of renal failure), but not in the serum levels of bilirubin, GPT and GOT (indicators of liver dysfunction and/or hepatocellular injury). Pretreatment of LPS-rats with SB 209670 (3 mg kg-1, i.v. bolus 15 min prior to LPS) significantly augmented the serum levels of creatinine, bilirubin, GPT and GOT caused by endotoxin. In addition, endotoxaemia caused, within 15 min, an acute metabolic acidosis (falls in pH, HCO3- and base excess) which was compensated by hyperventilation (fall in PaCO2). Pretreatment of LPS-rats with SB 209670 (3 mg kg-1, i.v. bolus) significantly augmented the metabolic acidosis caused by LPS. 6. Thus, the non-selective ETA/ETB receptor antagonist, SB 209670, augments the degree of (i) hypotension, (ii) vascular hyporeactivity to noradrenaline, (iii) renal dysfunction and (iv) metabolic acidosis caused by endotoxin in the anaesthetized rat. In contrast to rats treated with LPS alone, LPS-rats treated with SB 209670 exhibited liver dysfunction and hepatocellular injury. We propose that the release of endogenous ET-1 serves to maintain blood pressure and subsequently organ perfusion in septic shock. |
| 1996 | Increased concentrations of cytokines and adhesion molecules in patients after repair of abdominal aortic aneurysm. | Eur J Surg | To evaluate the association between inflammatory mediators and clinical outcome in patients after repair of abdominal aortic aneurysms.Prospective study.University hospital, The Netherlands.30 Consecutive patients who had undergone elective or acute repair of abdominal aortic aneurysms.Plasma concentrations of the cytokines tumour necrosis factor (TNF), interleukin-6 (IL-6) and interleukin-8 (IL-8) as well as soluble TNF receptors and the soluble (s) adhesion molecules E-selectin and intercellular adhesion molecule 1 (ICAM-1) were measured and correlated with the degree of systemic hypotension (shock: hypotension more than 15 minutes) and clinical outcome.Peak plasma concentrations of TNF and IL-6 were significantly higher in shocked patients (p < 0.005 and p < 0.0005, respectively) and those who died (both p < 0.01), whereas concentrations of IL-8 increased only when shock complicated rupture of the aneurysm (p < 0.01). Increases in the concentrations of TNF receptors reflected impaired renal function. In contrast to sE-selectin concentrations, peak sICAM-1 concentrations were significantly higher in shocked patients (p < 0.01) and those that died (p < 0.01).These results strongly suggest that increased concentrations of sICAM-1 and IL-6 reflect the inflammatory response induced by ischaemia after repair of an abdominal aortic aneurysm, and indicate that the postoperative course is likely to be complicated. |
| 1996 | Inhibition of factor XII in septic baboons attenuates the activation of complement and fibrinolytic systems and reduces the release of interleukin-6 and neutrophil elastase. | Blood | In previous studies, we have shown that administration of monoclonal antibody (MoAb) C6B7 against human factor XII to baboons challenged with a lethal dose of Escherichia coli abrogates activation of the contact system and modulates secondary hypotension. To evaluate the contribution of activated contact proteases to the appearance of other inflammatory mediators in this experimental model of sepsis, we studied the effect of administration of MoAb C6B7 on activation of complement and fibrinolytic cascades, stimulation of neutrophil degranulation, and release of the proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). Activation of the complement system, as reflected by circulating C3b/c and C4b/c levels, was significantly reduced in five animals that had received MoAb C6B7 before a lethal dose of E coli as compared with five control animals that had been given a lethal challenge only. Inhibition of contact activation also modulated the fibrinolytic response, since the release of tissue-type plasminogen activator (t-PA) and the appearance of plasmin-alpha2-antiplasmin (PAP) complexes into the circulation was significantly attenuated upon pretreatment with anti-factor XII MoAb. In contrast, plasma levels of plasminogen activator inhibitor (PAI) were modestly enhanced in the treatment group. Degranulation of neutrophils, as assessed by circulating elastase-alpha1-protease inhibitor complexes, and release of IL-6 but not of TNF-alpha was decreased in anti-factor XII-treated animals. Observed differences in the inflammatory response between treatment and control groups were not likely due to different challenges, since the number of E coli that had been infused, as well as circulating levels of endotoxin after the challenge, were similar for both groups. These data suggest that activation of the contact system modulates directly or indirectly various mediator systems involved in the inflammatory response during severe sepsis in nonhuman primates. |
| 1996 | Effect of aminoguanidine on in vivo expression of cytokines and inducible nitric oxide synthase in the lungs of endotoxemic rats. | Res Commun Mol Pathol Pharmacol | Endotoxemia results in the release of multiple mediators such as tumor necrosis factor alpha (TNF-infinity), interleukin-1 beta (IL-1 beta), and nitric oxide (NO), which is thought to be responsible for the hypotension of septic shock. Although there are many reports on the presence of these mediators in serum, in vivo expression of TNF-infinity, IL-1 beta and inducible nitric oxide synthase (iNOS) at the tissue level has not been studied extensively. We investigated in vivo expression of these cytokines and iNOS in the lungs of rats that were injected with saline, endotoxin or endotoxin plus aminoguanidine (AG), an inhibitor of iNOS. Expression of TNF-infinity, IL-1 beta and iNOS was absent in control (saline treated) but was increased in endotoxin treated animals. In animals treated with endotoxin plus AG (400 mg/kg), expression of iNOS was markedly inhibited whereas there was no effect on expression of TNF-infinity and IL-1 beta. The inhibitory effect of AG was probably dose dependent because a lower concentration of AG (50 mg/kg) showed no change in the expression of iNOS. |
| 1996 | Group A streptococcal bacteremia: the role of tumor necrosis factor in shock and organ failure. | J Infect Dis | Severe group A streptococcal infections associated with early onset shock and multiorgan failure define the streptococcal toxic shock syndrome. In the United States, group A streptococcal strains most commonly isolated are M types 1 and 3, which produce pyrogenic exotoxin type A. The role of tumor necrosis factor (TNF)-alpha and the dynamics of cardiovascular and laboratory abnormalities were investigated in a baboon model of group A Streptococcal bacteremia that mimics human Streptococcal toxic shock syndrome. Profound hypotension, leukopenia, metabolic acidosis, renal impairment, thrombocytopenia, and disseminated coagulopathy developed within 3 h after intravenous infusion of M type 3, pyrogenic exotoxin A-producing group A streptococci. Serum TNF-alpha peaked at 3 h and returned to baseline by 10 h. Mortality was 100%. Anti-TNF-alpha monoclonal antibody treatment markedly improved mean arterial blood pressure, tissue perfusion, and survival, suggesting that TNF-alpha plays an important role in the induction of shock and organ failure in group A streptococcal bacteremia. |
| 1996 | TNF-alpha and the pathophysiology of endotoxin-induced acute respiratory failure in sheep. | J Appl Physiol (1985) | We studied changes in cardiovascular and pulmonary function during prolonged endotoxemia in conscious sheep. Sheep with chronic lung lymph fistulas received a 12-h infusion of Escherichia coli endotoxin (10 ng x kg-1 x min-1) and allowed to recover for 12 h. Supportive therapies were withheld. Prolonged endotoxemia without volume support caused systemic hypotension associated with reduced cardiac output and increased systemic vascular resistance, pulmonary hypertension, and acute lung injury with progressive respiratory failure. Plasma tumor necrosis factor-alpha (TNF-alpha) concentrations increased transiently. Sustained pulmonary hypertension and increased pulmonary and systemic vascular resistances contributed to a poor outcome in 9 of 34 sheep (26%). Plasma TNF-alpha concentrations were significantly greater in survivors with sustained pulmonary hypertension and in nonsurviving sheep than in surviving sheep without pulmonary hypertension. Endotoxin (1 ng/ml) increased neutrophil expression of TNF-alpha in vitro. Addition of interleukin-6 prevented this response. Synthesis and release of TNF-alpha may be an important proximal event influencing the development of sustained pulmonary hypertension and progressive respiratory failure with endotoxemia. Interleukin-6 may contribute to the phasic nature of the TNF-alpha response. |
| 1996 | Prolactin inhibits the increased cytokine gene expression in Kupffer cells following haemorrhage. | Cytokine | Kupffer cells are an important source of proinflammatory cytokines and contribute to the systemic inflammatory response observed following haemorrhagic shock. The systemic release of cytokines, such as TNF-alpha, IL-1 beta, IL-6, etc., has been associated with the decreased host immune and organ dysfunction following hypotension. Studies indicate that anterior pituitary hormone prolactin (PRL) plays an important role in the regulation of lymphocyte proliferation and macrophage function in vivo, as well as in vitro. However, it is not known what effects PRL administration has on Kupffer cells proinflammatory mediator release following haemorrhage. Therefore, it was the aim of this study to determine the effect of in vivo PRL administration on cytokine gene expression in Kupffer cells after haemorrhage. To study this, C3H/HeN male mice were bled to and maintained at a mean arterial pressure of 35 mmHg for 60 minutes, then resuscitated with shed blood, and segregated into two groups: one group was treated with PRL (100 micrograms/25 g body weight subcutaneously) while the other group received saline-vehicles. This was followed with lactated Ringer's solution (2 x the volume of shed blood). Two hours thereafter, the animals were sacrificed, Kupffer cells were isolated and stimulated with or without 10 micrograms/ml LPS for 1 hour. Total RNA was extracted and cytokine mRNA was detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results demonstrated that haemorrhage markedly increased the level of mRNA for IL-1 beta, IL-6, TGF-beta and TNF-beta in Kupffer cells. However, in vivo PRL treatment significantly decreased the cytokine gene expression in Kupffer cells following haemorrhage. This indicates that PRL may be useful in blunting the systemic inflammatory response associated with cell and organ depression following shock. |
| The role of tumor necrosis factor in endotoxic shock. | Ann Clin Lab Sci | Tumor necrosis factor (TNF) has been implicated in hemodynamic changes of endotoxic shock. The temporal relationship of hypotension and TNF release in endotoxemia was studied. Carotid arteries of five intubated rats were cannulated and Escherichia coli 0127:B8 lipopolysaccharide (LPS) was infused over 10 seconds. Arterial blood pressure (ABP), heart rate, and plasma TNF concentrations were measured at 0, 5, 15, 30, and 60 mins. Five to 15 mins after LPS, there was a marked decline in ABP (146 +/- 23 vs 57 +/- 5 mm Hg, p < 0.005), without a significant rise in TNF. The heart rate did not change. From 15 to 60 mins, there was a rise in TNF concentrations (523 +/- 333 vs 5783 +/- 629 pg/ml, p < 0.005) while the same degree of hypotension persisted. It is concluded that early hypotension after acute endotoxemia is not dependent on TNF alone. However, TNF may play a role in sustaining hypotension after endotoxemia. |
| 1996 | The role of tumor necrosis factor and nitric oxide in the acute cardiovascular response to endotoxin. | Ann Surg | This study was designed to examine the differential effects of tumor necrosis factor (TNF) and nitric oxide on the acute cardiovascular changes that occur in response to endotoxemia.Recent studies have suggested that some, if not all, of the cardiovascular effects of TNF are mediated through release of nitric oxide. However, the mechanisms through which TNF and nitric oxide induce hypotension and shock in vivo in response to systemic endotoxemia remain poorly characterized, despite current interest in the use of nitric oxide antagonists to ameliorate septic shock.A reproducible model of endotoxemia was established in adult Sprague-Dawley rats. The acute cardiovascular changes that occur after bolus infusion of endotoxin was then determined in rats treated with either TNF antibody, N-methyl arginine, or both.Inhibition of either TNF or nitric oxide restores mean arterial blood pressure to normal after endotoxemia (p < 0.05). However, nitric oxide exerts its effects principally on the peripheral vasculature, whereas TNF appears to act on the myocardium. A combination of TNF antiserum pretreatment and N-methyl arginine administration is necessary to return mean arterial blood pressure to normal 60 minutes after endotoxin infusion.Tumor necrosis factor and nitric oxide mediate the acute cardiovascular effects of endotoxemia through distinct mechanisms. Nitric oxide is released as a result of both TNF-dependent and TNF-independent mechanisms, whereas the cardiovascular effects of TNF are only partially mediated through nitric oxide. |
| 1995 | Indirect evidence for stimulation of nitric oxide release by tumour necrosis factor-alpha in human veins in vivo. | Cardiovasc Res | The detrimental haemodynamic changes observed in septicaemia are generalised vasodilation, arterial hypotension, and hyporesponsiveness to vasopressor compound, all of which could be explained by the release of an endogenous vasodilator. Experimental and clinical evidence suggests that tumour necrosis factor-alpha (TNF) induces the expression of vascular nitric oxide (NO) synthase within hours and that NO released from smooth muscle cells could be involved in the pathogenesis of septic shock. The aim of this study was to investigate the role of NO in the vascular effects of TNF.Using the dorsal hand vein compliance technique, the effect of the NO synthase inhibitor L-NG-monomethyl-arginine (L-NMMA) on alpha 1-adrenergic responsiveness (phenylephrine 1.25-8000 ng/min) was studied after prolonged local venous infusion of TNF (8.7 micrograms in 5 h) in 9 volunteers and in 6 volunteers without previous cytokine exposure.Mean (+/- s.e.) maximum phenylephrine constriction (Emax) was 73 +/- 6% and log dose-rates exerting 50% of Emax (log ED50) were 3.2 +/- 0.09 (geometric mean: 1535 ng/min). Local co-administration of L-NMMA at a dose sufficiently high to block NO formation (3.4 mumol/min) increased venous sensitivity to phenylephrine threefold (log ED50 2.8 +/- 0.1, P < 0.015; geometric mean: 574 ng/min) whereas Emax was similar (73 +/- 5%). In the controls the phenylephrine dose-response relationship remained unaffected by simultaneous administration of L-NMMA.As no basal release of NO occurs in hand veins without previous exposure to TNF these results provide direct evidence for induction of NO formation in the human vasculature and consecutive resistance to alpha-adrenergic venoconstriction. NO might, therefore, be a key mediator of haemodynamic impairment in humans under conditions with known elevations of circulating TNF, such as a septic shock. |
| 1995 | Role for intracellular platelet-activating factor in the circulatory failure in a model of gram-positive shock. | Br J Pharmacol | 1. This study investigates the effects of two structurally different antagonists of platelet-activating factor (PAF), BN52021 and WEB2086, on the circulatory and renal failure elicited by lipoteichoic acid (LTA) from Staphylococcus aureus (an organism without endotoxin) in anaesthetized rats. 2. Administration of LTA (10 mg kg-1, i.v.) caused hypotension and vascular hyporeactivity to noradrenaline (1 microgram kg-1, i.v.) WEB2086 (5 mg kg-1, i.v., 20 min before and 150 min after LTA) inhibited the delayed fall in mean arterial blood pressure (at 300 min: 99 +/- 6 mmHg vs. 75 +/- 6 mmHg, P < 0.01) and prevented the decrease in pressor response to noradrenaline (at 300 min: 36 +/- 5 mmHg min vs. 17 +/- 5 mmHg min, P < 0.01). Surprisingly, BN52021 (20 mg kg-1, i.v., 20 min before and 150 min after LTA) neither prevented the hypotension (74 +/- 6 mmHg) nor the vascular hyporeactivity (21 +/- 5 mmHg min). However, BN52021 inhibited the hypotension to injections of PAF as well as the circulatory failure elicited by lipopolysaccharides (10 mg kg-1, i.v.). 3. LTA caused an increase in plasma concentration of creatinine from 39 +/- 5 microM (sham-operated) to 70 +/- 8 microM and urea from 4.7 +/- 0.1 to 13.1 +/- 1.6 mM. The renal failure elicited by LTA was significantly inhibited by WEB2086 (creatinine: 45 +/- 4 microM and urea: 5.7 +/- 0.7 mM), but not by BN52021. 4. The induction of nitric oxide synthase activity in lungs by LTA was attenuated by WEB2086 from 98 +/- 17 to 40 +/- 15 pmol L-citrulline 30 min-1 mg-1 protein (P < 0.01), but not by BN52021 (148 +/- 21 pmol L-citrulline 30 min-1 mg-1 protein). Similarly, WEB2086, but not BN52021, inhibited the increase in plasma nitrite concentration associated with the delayed circulatory failure caused by LTA. The release of tumour necrosis factor-alpha (TNF-alpha) after injection of LTA was not attenuated by WEB2086. 5. The induction of nitrite release by cultured macrophages activated with LTA (10 micrograms ml-1 for 24 h) was inhibited by 74 +/- 4% by WEB2086 (3 x 10(-4) M), but not by BN52021, indicating that only WEB2086 acts on intracellular PAF receptors. 6. Thus, the intracellular release of PAF contributes to the circulatory and renal failure and induction of nitric oxide synthase elicited by LTA in anaesthetized rats. The difference between the two structurally different PAF antagonists in our septic shock models using either LTA or lipopolysaccharide (LPS), shows the importance of models for Gram-positive sepsis in the elucidation of the pathophysiology of septic shock and for the evaluation of potential drugs. |
| 1995 | Protective effects of reconstituted high-density lipoprotein in rabbit gram-negative bacteremia models. | J Lab Clin Med | Reconstituted high-density lipoproteins (rHDLs) have the ability to bind bacterial lipopolysaccharide and to reduce its endotoxin activity in vitro and in vivo. The aim of the present studies was to investigate the therapeutic potential of rHDL in bacteremia models. Gram-negative sepsis was induced in anesthetized rabbits by intravenous infusion of Escherichia coli organisms (4 x 10(9) CFU/kg infused over 2 hours) and treated with appropriate antibiotics. rHDL or placebo was infused either before (prophylaxis) or 1 hour after (therapy) the beginning of the bacterial challenge. In the control groups, the bacterial challenge resulted in transient bacteremia, high plasma levels of lipopolysaccharide, secretion of TNF, and symptoms of sepsis, including hypotension and acidosis. rHDL had no influence on blood bacterial counts; however, plasma lipopolysaccharide levels were significantly reduced. Peak plasma TNF concentrations were reduced after prophylactic but not after therapeutic rHDL administration. Both prophylactic and therapeutic rHDL improved clinical outcome: acidosis was significantly attenuated and blood pressure tended to be higher in the rHDL groups. No effects of rHDL were seen in a similar model of gram-positive sepsis induced by the infusion of Staphylococcus aureus. |
| 1995 | Lack of effect of TNF antibodies on the cardiovascular sequelae of lipopolysaccharide infusion in conscious rats. | Br J Pharmacol | 1. The aims of the present study were to determine the profile of tumour necrosis factor (TNF) release, and the effect of monoclonal antibodies to TNF, on the changes in regional haemodynamics and the responses to vasodilator and vasoconstrictor challenges, during a continuous 24 h low dose infusion of lipopolysaccharide (LPS) in conscious rats. 2. Male Long Evans rats were chronically instrumented for measurement of regional haemodynamics (renal, superior mesenteric and hindquarters) and were challenged with 3 min infusions of acetylcholine (22 nmol min-1), methoxamine (120 nmol min-1), salbutamol (0.83 nmol min-1) and bradykinin (14.4 nmol min-1). The rats were given either saline, or the TNF antibodies, TN3g1 or TN3g2a, 1 h before the start of a continuous infusion of LPS (150 micrograms kg-1 h-1) and were subsequently re-tested with the vasodilator and vasoconstrictor challenges 2, 6 and 24 h after the start of the LPS infusion. 3. Prior to infusion of LPS, TNF was not detectable in the plasma. During continuous infusion of LPS there was a transient elevation in plasma TNF levels, reaching a maximum (approximately 2300 pg ml-1) after approximately 1 h, and returning to undetectable levels after approximately 3 h of LPS infusion. 4. In the saline pretreated group, after 1-2 h of LPS infusion, there was a small hypotension and a marked renal vasodilation; 6 h after the start of LPS infusion there was a minor elevation in MAP above control levels, renal vasodilatation was maintained and a hindquarters vasoconstriction occurred; after 24 h of LPS infusion, there was a hypotension and renal and hindquarters vasodilatation. There were significant reductions in the tachycardic and renal vasodilator responses and an enhanced depressor response to acetylcholine after 24 h of LPS infusion. LPS infusion also caused a generalized hyporesponsiveness to the cardiovascular effects of methoxamine and salbutamol. The major changes in response to bradykinin were reduced tachycardic and enhanced depressor responses throughout the LPS infusion, a biphasic decrease and increase in renal conductance and enhanced hindquarters vasodilatation at 24 h. 5. Pretreatment with either TN3g1 or TN3g2a antibodies had no major effects on the changes in resting haemodynamics, or on the changes in response to methoxamine, salbutamol or bradykinin challenges during LPS infusion. However, the tachycardic responses to acetylcholine were generally preserved, and its hypotensive effect after 24 h of LPS infusion was not enhanced after TN3g1 or TN3g2a pretreatment. Thus, despite substantial, but transient, elevation of plasma TNF levels during continuous LPS infusion, it appears that the majority of cardiovascular changes were dependent on factors other than plasma TNF. |
| 1995 | Induction of TNF-alpha and proinflammatory secretory phospholipase A2 by intravenous administration of CAMPATH-1H in patients with rheumatoid arthritis. | J Rheumatol | To test the effect of infusions of CAMPATH-1H on levels of proinflammatory secretory phospholipase A2 (sPLA2) and tumor necrosis factor alpha (TNF-alpha) in patients with rheumatoid arthritis (RA).Two patients with RA were infused with CAMPATH-1H; extracellular nonpancreatic sPLA2 activity was tested using radiolabelled E. coli membrane phospholipid, and circulating TNF-alpha levels were tested by ultrasensitive immunoassay.Circulating TNF-alpha began to rise within the first 2 h after infusion, reaching > 1000-fold values compared to preinfusion levels. Circulating sPLA2 activity began to rise a few hours after the start of infusion and reached extremely high values in 12 h, concomitant with fever and hypotension. The activity of sPLA2 decreased to pretreatment values in 3-18 days after infusion.The mechanism leading to the increase of TNF-alpha and hyperphospholipasemia A2 has not been elucidated. It is possible that CAMPATH-1H activates cells that synthesize and release TNF-alpha and sPLA2, and/or that it induces interleukin 2 release, which in turn activates TNF-alpha, with subsequent release of sPLA2. |
| 1995 | Enhanced production of nitric oxide by blood-dialysis membrane interaction. | J Am Soc Nephrol | Nitric oxide (NO) is a powerful vasoactive product of endothelial origin, and one of its major effects is vasodilation, leading to hypotension. The role of NO in some complications of uremia is still debated. This study evaluated whether endothelial NO synthase activity could be modulated by the exposure of healthy blood to hemodialysis materials. In vitro hemodialysis sessions were performed with cuprophan and polymethylmethacrylate membranes. Blood samples from a healthy donor after recirculation for 0, 5, 15, 30, and 60 min were coincubated for 6 h with a murine endothelial cell line (t.End.1); mRNA for inducible NO synthase and enzyme activity, measured as (3H)citrulline produced from (3H)arginine, were detected. The release of interleukin (IL)-1 beta and tumor necrosis factor-alpha (TNF-alpha) from recirculating lymphomonocytes was measured, too. The NO synthase activity of endothelial cells was stimulated by blood dialyzed with cuprophan, peaking at 15 min (11-fold increase in comparison to the basal values), whereas polymethylmethacrylate was ineffective (P < 0.01 versus Cuprophan). Dialysis with cuprophan, but not with polymethylmethacrylate, induced in endothelial cells the expression of mRNA encoding for inducible NO synthase. The release of IL-1 beta and TNF-alpha after 6 h by recirculating lymphomonocytes paralleled the NO synthase activity profile in endothelial cells and was significantly higher after cuprophan exposure than after polymethylmethacrylate (P < 0.0001). In conclusion, the activity of endothelial NO synthase can be enhanced during the dialysis sessions by the interaction of lymphomonocytes with the membranes, possibly via TNF-alpha and IL-1 beta production. |
| 1995 | Systemic leakage and side effects of tumor necrosis factor alpha administered via isolated limb perfusion can be manipulated by flow rate adjustment. | Arch Surg | The tolerated systemic dose of recombinant tumor necrosis factor alpha (rTNF-alpha) is very limited, since its administration leads to a severe septic shock-like condition. Its implementation in isolated limb perfusion (ILP) for metastatic melanoma or advanced soft-tissue sarcoma confined to the limb facilitates doses of rTNF-alpha 10 times higher than the systemic tolerated dose. However, with the traditional high flow rate used in ILP, systemic leakage and side effects are not eliminated.To determine if a lower perfusion flow rate would reduce leakage and consequently toxic effects.Isolated limb perfusion was performed for melanoma and soft-tissue sarcoma confined to the limb using a flow rate of 869 +/- 122 mL/min in nine patients (group 1) and a lower rate of 286 +/- 62 mL/min in six patients (group 2).The systemic leakage rate was 12.5% +/- 2.9% in group 1, compared with 2.3% +/- 1.0% in group 2 (P = .003). Peak TNF-alpha levels were 29,000 +/- 2700 pg/mL in group 1, higher than 1580 +/- 1355 pg/mL in group 2 (P = .02). The tachycardia, hypotension, increased cardiac output, decreased systemic vascular resistance, bilirubinemia, elevation of liver enzyme levels, hypocholestrolemia, thrombocytopenia, and prolongation of prothrombin and partial thromboplastin times all observed in group 1 were significantly attenuated or eliminated in group 2. The limb PO2, PCO2, pH, and viability remained similar in both groups. Also, the tumor response rate remained high and was unaffected by the decrease in flow rate.Decreasing perfusion flow rate during ILP results in diminished leakage of TNF-alpha. Consequently, the systemic hemodynamic, metabolic, and hematologic toxic effects are virtually abolished. |
| 1995 | Novel muteins of human tumor necrosis factor with potent antitumor activity and less lethal toxicity in mice. | Int J Cancer | Eight muteins of recombinant human tumor necrosis factor-alpha (rhTNF; 1SSSRTP...29RR...155L), in which 29Arg was replaced by another amino acid, were prepared and their anti-tumor effects in BALB/c mice bearing Meth A fibrosarcoma were evaluated. The therapeutic indices, which mark the extent of the therapeutically effective dose, of V29 (29Arg-->Val) and D29 (-->Asp) were 3.5 and 3.2, respectively, whereas that of rhTNF was 1.4. Clearly, the therapeutically effective range of these muteins was extended along with a decrease in lethal toxicity. V29 did not produce hypotension in the rat system, but D29 did. In addition, V29 showed potent anti-tumor activity (Tumor Volume Inhibition Rate = 81% on day 15 after implantation) in 3 consecutive injection schedules despite the decreases in toxicity compared with rhTNF. The relative receptor binding constant was determined using HEp-2 cells (expressing mainly 55-kDa-TNF receptor; p55R) and HL60 cells (expressing mainly 75-kDa-TNF receptor; p75R), and revealed that the reduced toxicity of V29 in mice was due to the reduced binding to p55R (34% of rhTNF). On the other hand, the ratio of the constants HEp-2/HL60 of V29 was 11 in comparison with the value of 1.0 for rhTNF, suggesting that this mutein binds preferentially to p55R. The biological activities in human cell lines (HEp-2 and HL60 cells) correlated well with the binding activities to each receptor in vitro. Therefore, the much lower toxicity and the potent anti-tumor activity of this mutein suggest that V29 merits further investigation in pre-clinical and clinical trials. |
| 1995 | Exercise-associated collapse in cyclists is unrelated to endotoxemia. | Med Sci Sports Exerc | Endotoxemia occurs when intestinal ischemia allows bacterial lipopolysaccharide to translocate from colonic flora into the bloodstream, which triggers release of cytokines that can cause hypotension, rigors, fever, shock, and even death. Recently, blood endotoxin levels were shown to be higher in athletes needing medical attention (330 pg.ml-1) than in their competitors with similar performances (81 pg.ml-1). Though there were no data showing that these athletes had elevated core temperatures or severe illness, speculation followed that endotoxin may play a causal role in heat stroke. We examined the relationship between endotoxemia and mild post-exertional illness in 39 cyclists after a 100-mile ride. Thirteen cyclists had at least one of the following: orthostatic hypotension, rigors, nausea, vomiting, diarrhea, or syncope. Only 2/26 case-controls had any of these symptoms. Data were collected on vital signs, hemoglobin, sodium, creatine kinase, creatinine, and uric acid. Endotoxin titer was determined by chromogenic assay; tumor necrosis factor alpha (TNF-alpha) titer was determined by ELISA. One ill cyclist had an endotoxin level of 330 pg.ml-1, one control had an endotoxin level of 150 pg.ml-1, but endotoxin level was < or = 64 pg.ml-1 in all others. Comparison of pre- and post-ride data showed that controls increased creatine kinase activity (154 +/- 34 vs 561 +/- 191 IU.dl, P < 0.05), creatinine concentration (1.5 +/- 0.0 vs 1.6 +/- 0.0 mg.dl-1, P < 0.05), and uric acid concentration (5.4 +/- 0.3 vs 6.3 +/- 0.3 mg.dl-1, P < 0.05). Ill cyclists had lower serum sodium than post-ride controls (138 +/- 2 vs 142 +/- 0.6 mEq.l-1, P < 0.05), but there were no differences between groups in CK, creatinine, or uric acid. These findings suggest that endotoxemia may complicate, but does not cause mild post-exertional illness in cyclists. |
| 1995 | Phase Ia/Ib trial of bispecific antibody MDX-210 in patients with advanced breast or ovarian cancer that overexpresses the proto-oncogene HER-2/neu. | J Clin Oncol | MDX-210 is a bispecific antibody that binds simultaneously to type I Fc receptors for immunoglobulin G (IgG) (Fc gamma RI) and to the HER-2/neu oncogene protein product. MDX-210 effectively directs Fc gamma RI-positive effector cells such as monocytes and macrophages to phagocytose or kill tumor cells that overexpress HER-2/neu. The goals of this phase Ia/Ib trial were to determine the maximum-tolerated dose (MTD) and/or the optimal biologic dose (OBD) of MDX-210.Patients with advanced breast or ovarian cancer that overexpressed HER-2/neu were eligible for treatment. Cohorts of three patients received a single intravenous (IV) infusion of MDX-210 at increasing dose levels from 0.35 to 10.0 mg/m2.Treatment was well tolerated, with most patients experiencing transient grade 1 to 2 fevers, malaise, and hypotension only. Two patients experienced transient grade 3 hypotension at 10.0 mg/m2. Transient monocytopenia and lymphopenia developed at 1 to 2 hours, but no other hematologic changes were observed. Doses of MDX-210 > or = 3.5 mg/m2 saturated > or = 80% of monocyte Fc gamma RI and produced peak plasma concentrations > or = 1 microgram/mL, which is greater than the concentration for optimal monocyte/macrophage activation in vitro. Elevated plasma levels of the monocyte products tumor necrosis factor alpha (TNF alpha), interleukin-6 (IL-6), granulocyte colony-stimulating factor (G-CSF), and neopterin were observed with maximal levels at doses > or = 7.0 mg/m2. Localization of MDX-210 in tumor tissue was demonstrated in two patients. One partial and one mixed tumor response were observed among 10 assessable patients.MDX-210 is immunologically active at well-tolerated doses. The MTD and OBD is 7 to 10 mg/m2. |
| 1995 | Novel mutein of tumor necrosis factor alpha (F4614) with reduced hypotensive effect. | J Interferon Cytokine Res | To eliminate systemic toxicity, including the hypotension associated with human tumor necrosis factor alpha (TNF-alpha), we constructed mutant proteins (muteins) by mean of genetic engineering. A novel mutein, F4614, containing mutations of 5Thr-->Gly and 6Pro-->Asp, which resulted in the introduction of cell-adhesive Arg-Gly-Asp and 29Arg-->Val, had remarkably reduced hypotensive effects and lower lethality. We present evidence that the Arg-->Val mutation at position 29 is largely responsible for the reduced hypotensive effect. This effect of F4614 was thought to be closely correlated with its low inducibility of nitric oxide and prostaglandin E2 in vivo. In addition, the therapeutically effective dose of F4614 to MethA fibrosarcoma-transplanted mice was increased compared with that of TNF-alpha, indicating a wide therapeutic index. These results indicated that F4614 has several advantages as a systemic therapeutic drug in the treatment of cancer. |
| 1995 | Anti-tumor necrosis factor-alpha prevents decreased ventricular contractility in endotoxemic pigs. | Am J Respir Crit Care Med | It is not known how the decrease in left ventricular contractility following endotoxin exposure is mediated, or whether this decrease is preventable by antibodies to tumor necrosis factor-alpha (TNF alpha). Four groups of six anesthetized and instrumented pigs were pretreated with ovine polyclonal antibody to human TNF alpha (anti-TNF alpha), nonspecific IgG, or saline, and then treated with either endotoxin or saline. We measured hemodynamics and left ventricular pressures (Millar catheter) and volumes (conductance catheter). Left ventricular contractility was assessed using the slope (Emax) of the end-systolic pressure-volume relationship. Four hours after the start of endotoxin infusion in the nonspecific IgG pretreated group, Emax had decreased by 44 +/- 6% (p < 0.05), mean arterial pressure had decreased from 115 +/- 7 mm Hg to 70 +/- 10 mm Hg (p < 0.05), and cardiac output was rapidly decreasing after an initial increase (p < 0.05). Anti-TNF alpha significantly reduced the decrease in Emax (11 +/- 9%, p < 0.05), and the systemic hypotension (108 +/- 15 mm Hg to 99 +/- 6 mm Hg, p < 0.05), at 4 h, and prevented the late decrease in cardiac output. This suggests that TNF alpha is an important early mediator in sepsis leading to decreased left ventricular contractility. |
| 1995 | Prevention of endotoxin shock by an antibody against leukocyte integrin beta 2 through inhibiting production and action of TNF. | Int Immunol | Septic shock remains a serious disorder associated with high mortality. Accumulating evidence indicates that TNF is a major and essential mediator of endotoxin shock. We report here that administration of an antibody against CD18 dramatically reduced endotoxin-induced shock in rabbits as revealed by prevention of severe hypotension, metabolic acidosis and a pathological change suggestive of disseminated intravascular coagulation with concomitant inhibition of elevation of plasma TNF activity. The anti-CD18 antibody also inhibited the hypotension induced by administering recombinant TNF. Furthermore, an antibody against a ligand for CD18 complexes, intercellular adhesion molecule-1, also prevented TNF-induced shock as well as endotoxin shock in rabbits. These observations suggest that adhesion of leukocytes to endothelium may be of primary importance in the action of TNF as well as in the production of TNF in vivo and that the antibody against adhesion molecules could be of therapeutic benefit in life-threatening septic shock in humans. |
| 1995 | Hypoxemia in the absence of blood loss or significant hypotension causes inflammatory cytokine release. | Am J Physiol | Although hemorrhagic shock causes a significant elevation of circulating levels of proinflammatory cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, IL-6], it remains unknown whether hypoxemia per se in the absence of blood loss activates macrophages (Mø) to release increased amounts of these mediators. To study this, hypoxemia was induced in C3H/HeN mice by placing them in a plastic box that was flushed with a gas mixture containing 95% N2-5% O2 for 60 min, followed by return of the mice to room air. For control animals, the plastic box was flushed with room air. At 0, 2, or 24 h thereafter, blood samples were obtained, plasma was separated, and then peritoneal Mø (pMø) and Kupffer cells (KC) were isolated and incubated at 37 degrees C for 24 h with lipopolysaccharide. The Mø supernatants, as well as plasma samples, were assayed for TNF-alpha, IL-1 beta, and IL-6 with the use of specific bioassays. Hypoxemia induced a significant (P < 0.05) increase in plasma TNF-alpha levels during the entire study period while circulating IL-6 was elevated by 313% (P < 0.01) at 24 h after hypoxemia compared with shams. Moreover, the release of TNF-alpha, IL-1 beta, and IL-6 by pMø and KC was markedly increased after hypoxemia compared with shams. Thus, hypoxemia in itself, in the absence of any blood loss or tissue injury, induces release of proinflammatory cytokines, which may contribute to systemic inflammation following hypoxemia. |
| 1995 | Comparison of plasma cytokine levels in rats subjected to superior mesenteric artery occlusion or hemorrhagic shock. | Shock | The overall goal of this study was to compare the effects of systemic hypotension (hemorrhagic shock) versus local gut ischemia (superior mesenteric artery (SMA) occlusion) on cytokine production and bacteria/endotoxin translocation. Sham or actual SMA occlusion led to an increase in tumor necrosis factor (TNF), which was greatest at the end of the occlusion period, while the IL-6 response peaked 3 h post-SMA occlusion. The TNF and IL-6 response after hemorrhagic shock differed from that observed after SMA occlusion in that the peak response occurred later and was of lower magnitude (p < .05). Although the animals subjected to SMA occlusion had a significantly increased incidence of bacterial translocation to both the mesenteric lymph nodes and systemic organs compared to rats subjected to hemorrhagic shock, in neither group was the blood level of endotoxin elevated and there was no association between bacterial translocation and cytokine levels. These results suggest that different models of intestinal ischemia have different cytokine profiles and that the early TNF response associated with SMA occlusion model is primarily due to the laparotomy. |
| 1995 | The potential etiologic role of tumor necrosis factor in mediating multiple organ dysfunction in rats following intestinal ischemia-reperfusion injury. | Resuscitation | Endogenous inflammatory cytokines may function as mediators in the development of remote organ damage in response to local ischemic insult. This study was designed to (a) explore the potential role of tumor necrosis factor (TNF) formation in the pathogenesis of systemic tissue injury, (b) determine the relationship between induction of TNF and gut-derived endotoxemia and/or bacterial translocation, and (c) evaluate the protective effect of anti-TNF monoclonal antibody (MoAb) for vital organs following intestinal ischemia-reperfusion in rats. Animals were subjected to superior mesenteric artery occlusion (SMAO) for 45 min. Systemic plasma TNF levels increased rapidly after the onset of reperfusion, reaching a peak value 2 h later (P < 0.01). TNF elevation was found to be associated with gut origin endotoxemia, where the maximal TNF levels occurred approximately 2 h after the initial appearance of endotoxin in portal vein. Prophylactic treatment with anti-TNF MoAb markedly blunted the elevation in plasma TNF levels and afforded protection from the development of hypotension, vital organs dysfunction, and metabolic acidosis. Significant improvement in 48-h survival rate was observed by administration of anti-TNF MoAb prior to inducing ischemia (P = 0.007). These findings suggest that intestinal ischemia-reperfusion could result in TNF production, which may play a key role in mediating subsequent septic response and systemic tissue injury. It seems likely that passage of endotoxin and bacteria from the gut can be responsible for the TNF formation |
| 1995 | A phase IA/IB trial of anti-CD3 murine monoclonal antibody plus low-dose continuous-infusion interleukin-2 in advanced cancer patients. | J Immunother Emphasis Tumor Immunol | Preclinical studies have shown that anti-CD3 antibodies can enhance the in vitro activation of human T lymphocytes in combination with low-dose interleukin-2 (IL-2) and induce the in vivo rejection of murine tumors. A Phase IA/IB trial combining a murine monoclonal antibody, anti-CD3 antibody (OKT3), with low-dose continuous-infusion IL-2 was conducted in cancer patients to define the toxicity and immunologic effects of this combination. OKT3 administered weekly as a 15-min infusion at dose levels of 10, 100, 200, 400, and 600 micrograms/m2 was followed 18 h later by a 100-h infusion of IL-2 at 3 MIU/m2/day for 3 consecutive weeks. When feasible, patients also received the IL-2 course without OKT3 to assess the effects of OKT3 on the IL-2 regimen within the same patient. Thirty patients were enrolled onto the study, with 24 completing the OKT3/IL-2 course and 18 completing both OKT3/IL-2 and IL-2 alone courses. OKT3 administration was associated with acute hypotension with fevers of > 40 degrees C and in two patients cerebral vascular infarcts. At 600 micrograms/m2 OKT3, these toxicities were dose limiting. In a dose-dependent manner, OKT3 induced the transient release of tumor necrosis factor (TNF) and IL-6 into the serum and a profound lymphopenia. OKT3 did not significantly enhance the toxicity of this schedule of IL-2 administration. All solid tumor patients treated at 100-600 micrograms/m2 OKT3 showed induction of a human anti-murine antibody response prior to the third week of treatment. A patient with renal cell cancer treated at the 600-micrograms/m2 OKT3 dose level experienced a 4-month partial remission, and two mixed responses were observed in a sarcoma and a melanoma patient treated at 100- and 400-micrograms/m2 OKT3 dose levels, respectively. Most importantly, we were unable to demonstrate that the addition of OKT3 enhanced immune activation within peripheral blood based upon the magnitude of rebound lymphocytosis, increase in CD56+ or CD3+, CD25+ lymphocytes, induction of natural killer, lymphokine activated killer, or cytolytic T lymphocyte cytotoxicity, or release of serum cytokines (TNF, IL-6) or soluble CD25 (as assayed 24 h following IL-2 infusion). Therefore, this approach was ineffective at enhancing the immunologic effects of a low-dose continuous-infusion IL-2 regimen and will not be pursued further in clinical trials. |
| 1995 | Phase I study of sequentially administered recombinant tumor necrosis factor and recombinant interleukin-2. | J Immunother Emphasis Tumor Immunol | The purposes of this study were to determine the maximally tolerated dose (MTD) of IL-2 when sequentially administered following TNF (at its MTD), to identify any unique toxicities, and determine the immunomodulatory effects of this combination. Patients with metastatic cancer were treated with 160 micrograms/ml rTNF by rapid i.v. infusion for 5 days, followed by rIL-2 therapy daily at doses up to 18 x 10(6) IU/m2/day for 5 days and 6 x 10(6) IU/m2/day for 7 days. Cycles were repeated at 3- or 4-week intervals until progressive disease or unacceptable toxicity developed. Fifteen patients received 46 cycles of therapy (range 1-8, median 3). Major toxicities included hypotension, weight loss, and decreased performance status comparable to that reported with rIL-2 alone. No novel toxicities were identified. Two of 14 patients who received two cycles of therapy had objective responses (1 complete, 1 partial). Both occurred in patients with malignant melanoma, lasted 30 and 75 weeks, respectively, and included a complete response in liver metastasis. Dosage reductions of IL-2 were necessary for 3 patients over 11 treatment cycles (23%), and rTNF in 1 patient for 1 cycle (2%). The MTD of 5-day infusional rIL-2 was determined at 18 x 10(6) IU/m2/day. rTNF did not augment natural killer/lymphokine-activated killer activities beyond that commonly seen with IL-2 infusions. We conclude that full doses of rTNF can be combined with escalating rIL-2 infusions in an outpatient setting without additive toxicity and with clinical activity in patients with malignant melanoma. |
| 1995 | Endotoxin-resistant mice are protected from PAF-induced bowel injury and death. Role of TNF, complement activation, and endogenous PAF production. | Dig Dis Sci | C3H/HeJ (endotoxin-resistant) mice have been used widely in biological research. However, the mechanism of endotoxin (LPS) resistance is only partially understood. In this study, we first investigated the differences in response to PAF, a mediator of endotoxin shock, between normal and C3H/HeJ mice. We found that in control mice, PAF (2.5 micrograms/kg) caused shock, hemoconcentration, complement activation, intestinal hypoperfusion, and necrosis with 75% mortality, whereas all C3H/HeJ mice survived, without complement activation or intestinal injury, and manifesting only mild hypotension and hemoconcentration. PAF also caused elevated serum TNF-alpha in some control mice but not in C3H/HeJ mice. We also observed that PAF induces endogenous PAF production and intestinal phospholipase A2 activation in normal mice, whereas PAF production and phospholipase A2 are suppressed in C3H/HeJ mice. The low endogenous PAF production may account, at least in part, for the resistance to LPS and PAF of C3H/HeJ mice. |
| 1995 | Delayed circulatory failure due to the induction of nitric oxide synthase by lipoteichoic acid from Staphylococcus aureus in anaesthetized rats. | Br J Pharmacol | 1. This study investigates the effect of lipoteichoic acid (LTA) from the cell wall of Staphylococcus aureus, a micro-organism without endotoxin, on haemodynamics and induction of nitric oxide synthase (iNOS) in the anaesthetized rat. 2. Intravenous injection of LTA (10 mg kg-1) resulted in a decrease in blood pressure from 123 +/- 1 mmHg to 83 +/- 7 mmHg after 270 min (P < 0.001) and a reduction of the pressor response to noradrenaline (1 microgram kg-1) from 33 +/- 1 mmHg.min to 23 +/- 3 mmHg.min after 270 min (P < 0.05). 3. The delayed circulatory failure (hypotension and vascular hyporeactivity) caused by LTA was prevented by pretreatment of rats with dexamethasone (10 mg kg-1, 60 min prior to LTA) or the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA, 10 mg kg-1 h-1, i.v. infusion starting 30 min prior to LTA). 4. In contrast, treatment of rats with polymyxin B (0.05 mg kg-1), an agent which binds endotoxin (lipopolysaccharides, LPS), did not affect the delayed circulatory failure caused by LTA. Polymyxin B, however, attenuated the hypotension and vascular hyporeactivity to noradrenaline afforded by endotoxaemia (2 mg kg-1 LPS, i.v.) for 270 min. 5. The delayed circulatory failure caused by LTA was associated with a time-dependent increase in (i) the expression of iNOS protein in the lung (Western blot analysis), and (ii) iNOS activity. This increase in iNOS protein and activity was prevented by pretreatment of LTA-rats with dexamethasone (10 mg kg-1). 6. Intravenous injection of LTA resulted in an increase in serum tumour necrosis factor (TNF)-alpha(maximum at 90 min after LTA), which was attenuated by pretreatment of rats with dexamethasone(10 mg kg-1, 60 min prior to LTA). The magnitude of the rise in TNF-alpha caused by LTA was similar to the one elicited by LPS (10mgkg-', i.v.).7. Thus, an enhanced formation of nitric oxide following the induction of iNOS contributes importantly to the delayed vascular failure (hypotension and vascular hyporeactivity) caused by LTA in the anaesthetized rat. We suggest that the endogenous release of TNF-alpha contributes to the induction ofiNOS caused by LTA in vivo. |
| 1995 | The pathogenesis of experimental toxic shock syndrome: the role of interleukin-2 in the induction of hypotension and release of cytokines. | Shock | Toxic shock syndrome (TSS) is a multisystem disorder characterized by fever, hypotension, and involvement of three other organ systems. The etiologic agent is a toxigenic strain of Staphylococcus aureus which secretes the exotoxin, TSST-1. The toxin is a superantigen which stimulates the immune system to produce interleukin-1 (IL-1), interleukin-2, and tumor necrosis factor (TNF). We hypothesized that TSST-1 induces the release of IL-2 which in turn is either directly involved or acts via an additional mediator to produce hypotension. We submitted four pairs of normal anesthetized adult female baboons to intravenous boluses of TSST-1. One baboon in each pair received anti-IL-2 intravenously and anti-IL-2 receptor intrathyroidally 15 min prior to TSST-1. The other baboon received the same dose and placement of anti-sheep red blood cell antibody. Systolic and diastolic blood pressure was recorded continuously and mean arterial pressure was calculated and plotted. IL-1, IL-2, IL-6, and TNF were measured in serum at varying times before and after toxin administration. Systolic, diastolic, and mean arterial pressure were significantly lower in the sham-treated group versus the experimental (anti-IL-2/IL-2R) group (p < .05 for all variables). In addition no differences were seen in any of the measurements between experimentally treated baboons and those receiving no TSST-1.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1995 | A phase I trial of repeated tumour-infiltrating lymphocyte (TIL) infusion in metastatic melanoma. | Br J Cancer | The aim of the protocol was to evaluate the side-effects induced by repeated tumour-infiltrating lymphocyte (TIL) infusions in patients with metastatic melanoma (MM). Patients were to receive four TIL infusions at given intervals: every 3 weeks (two patients), every 2 weeks (3 patients) and weekly (4 patients). All patients were evaluated and received a total of 34 TIL infusions. The total number of TILs administered varied from 0.65 to 2.34 x 10(11) cells. TIL phenotypes were predominantly CD8+ (two patients), CD4+ (4 patients), CD4+ then CD8+ (two patients) or CD56+ (two patient). Autocytotoxicity was only observed for one culture. Six patients presented at least one WHO grade 3 side-effect: hypotension (5 patients), dyspnoea (two patients), fever (one patient), fatigue (one patient), chills (two patients), diarrhoea (one patient), agitation (one patient), locoregional pain (two patients). Hypotension was constantly seen in patients who were given TILs every week. Two cases of minor pericarditis were recorded. No objective response to treatment was observed; 1 stable disease occurred in one patient and progression in eight. However, five patients presented a partial response on a tumour site for 1-4 months. Three patients presented signs of inflammation or softening at one tumour site. Plasma tumour necrosis factor alpha (TNF-alpha) levels were increased 1.2- to 22-fold after TIL infusion. TILs could be produced in sufficient quantity to perform this study, so repetitive infusions of TIL became possible on a weekly basis. However, no objective response was observed even when TIL infusions were performed weekly. An increase in circulating TNF-alpha was noted after TIL infusion. |
| 1995 | In vivo administration of endotoxin and tumor necrosis factor-alpha produce different effects on constitutive and inducible nitric oxide synthase activity in rat neutrophils and aorta ex vivo. | Proc Soc Exp Biol Med | Tumor necrosis factor-alpha (TNF-alpha) inhibits release of nitric oxide (NO) in vitro by stimulating the degradation of constitutive NO synthase (cNOS III) mRNA. However, TNF-alpha is believed to be the cytokine mediator of the hypotension and upregulation of inducible NO synthase (iNOS II) produced by gram-negative bacterial endotoxin (LPS). Some in vivo effects of TNF-alpha are opposite to those which occur in vitro. This study tested the hypothesis that in vivo administration of exogenous TNF-alpha and endogenously released TNF-alpha induce iNOS II activity and inhibit cNOS III activity, and thereby mediate the acute phase effects of LPS on blood pressure and the NO system in the rat. We show that LPS produces acute phase hypotension in ketamine anesthetized rats. The hypotension was associated with elevation of biologically active TNF-alpha in plasma, increased production of RNI (NO2- and NO3- anion) in rat neutrophils (PMN) and suppression of RNI production by A23187 (1 microM) stimulated thoracic aorta (RTA) ex vivo. TNA-alpha (10(6) U/ml, iv) did not produce acute phase hypotension but initially raised arterial blood pressure and heart rate (HR), did not increase RNI production by PMN, and inhibited RNI production by A23187 stimulated RTA ex vivo. Pretreatment of rats with the immunex monomeric soluble P75 receptor binding protein for TNF-alpha (TNFsr, 0.5 mg/kg, iv) 15 min prior to LPS administration decreased circulating TNF-alpha from 92,137 +/- 12,456 U/ml to undetectable levels as determined by the L929 bioassay. However, LPS-induced increases in RNI in PMN was enhanced and LPS-induced decreases in RNI production by RTA was inhibited by TNFsr. Thus, in vivo administration of TNF-alpha does not mimic the hemodynamic and NO-inducing effects of LPS. However, TNF-alpha mediates in part LPS-induced inhibition of RNI production by RTA. Thus, endogenous TNF-alpha is not required for LPS-induced acute phase hypotension or iNOS II activity. The importance of TNF-alpha in sepsis resides in systems other than iNOSII and blood pressure. |
| Inhibition of and sensitization to the lethal effects of tumor necrosis factor. | J Inflamm | The extension of the positive results obtained with tumor necrosis factor (TNF) in the locoregional treatment of cancer to systemic treatments requires the selective inhibition of its shock-inducing properties. In this paper, recent data regarding the mechanisms by which infections and tumors render mice extremely sensitive to the lethal effects of TNF as well as regarding the inhibition of the dose-limiting toxicities, hypotension and hepatotoxicity, are summarized. An interleukin-12 (IL-12) driven induction of interferon-gamma (IFN-gamma), probably in synergism with endogenous TNF, was found to mediate infection-induced sensitization. The sensitization induced by tumors develops independent of the IL-12/IFN-gamma axis but ultimately leads to a common step, which can be inhibited by alpha-CD11a and is specific for sensitization. Hypotension can be inhibited by methylene blue (MB), an inhibitor of the nitric oxide (NO)-induced activation of the cytosolic guanylate cyclase, without the indispensable protective properties of NO being affected. Finally, two acute phase proteins, alpha 1-acid-glycoprotein (AGP) and alpha 1-antitrypsin (AT), were able to protect against the TNF-induced liver failure. None of these three inhibitors seems to affect the antitumor effects of TNF. |
| 1995 | Cardiopulmonary effects of tumor necrosis factor-alpha in the piglet: influence of cyclooxygenase inhibition. | Biol Neonate | Tumor necrosis factor-alpha (TNF) is believed to play an important role in mediating many of the pathophysiologic changes accompanying bacterial sepsis. In order to characterize the cardiopulmonary responses to TNF in a young animal model and to determine to what extent these changes were secondary to cyclooxygenase byproducts, three groups of mechanically ventilated piglets received an infusion of either TNF, indomethacin followed by TNF (Indo+TNF) or neither (control). Compared to controls at 120 min, TNF resulted in the following changes beginning 30-60 min after the infusion began: mean pulmonary artery pressure (Ppa) increased from 1.7 +/- 0.3 to 4.4 +/- 0.7 kPa (13 +/- 2 to 33 +/- 5 mm Hg) (p < 0.001); cardiac output (CO) fell from 0.28 +/- 0.05 to 0.20 +/- 0.07 liters/kg/min (p < 0.01); mean arterial blood pressure (Psa) decreased from 9.5 +/- 1.2 to 7.9 +/- 1.9 kPa (71 +/- 9 to 59 +/- 14 mm Hg) as did pH from 7.49 +/- 0.04 to 7.13 +/- 0.17 (p < 0.001). Dynamic lung compliance (Cdyn) also decreased; however, pulmonary resistance (RI) remained unchanged. Thromboxane B2 (TxB2) rose in all animals at 60 min coincident with Psa elevation and was significantly blocked by Indo (p < 0.03). In the Indo+TNF group the early TNF-induced rise in Psa was blunted compared to the TNF group [2.9 +/- 1.2 vs. 3.6 +/- 0.8 kPa (22 +/- 3 vs. 27 +/- 6 mm Hg; p < 0.04)] as were the late decreases in pH and Psa (p < 0.04). There were no significant changes in Cdyn secondary to Indo. Although delayed, the hemodynamic changes observed with TNF infusion are similar to those reported for piglets receiving group B streptococci; however, in contrast to the latter the early changes secondary to TNF are only mildly effected by indomethacin. The significant improvement in the late occurring hypotension and acidosis suggests that TNF may act in part via the cyclooxygenase pathway as a mediator of the late hypotension associated with sepsis. |
| 1995 | [Effect of intravenous treatment with tumor necrosis factor alpha in patients with advanced cancer--phase I clinical trials]. | Przegl Lek | Tumor necrosis factor (TNF) is the protein produced by the activated macrophages with the ability to produce haemorrhagic necrosis of tumor, and in some cases complete tumor remission in vivo, as well as cytotoxicity of neoplastic cells in vitro. These properties made us undertake clinical studies on THF. We performed a Phase I assessment of recombinant human THF alpha in 16 patients with advanced solid neoplasms. Therapy consisted of a 30 minute intravenous (IV) infusion on day i thraugh 5, every 2 weeks. Daily doses ranged from 25 micrograms/m2 to 200 micrograms/m2. Side effects hypotension tachycardia nausea or vomiting, headache. No major changes in liver or renal function were seen. |
| 1995 | Neutrophil activation, tumor necrosis factor, and survival after endotoxic and hemorrhagic shock. | J Cardiovasc Pharmacol | Polymorphonuclear neutrophils (PMNs) may contribute to organ injury in both hemorrhagic and endotoxic shock. Both models of shock exhibit a "flight of the leukocytes," but the mechanisms for entrapment of leukocytes in the microcirculation differ. The objective of this study was to investigate lipopolysaccharide (LPS)-induced shock and hemorrhagic shock with similar survival rates, in terms of circulating PMNs, activated circulating PMNs, plasma tumor necrosis factor (TNF) activity, and PMN adhesion. In the LPS protocol, rats received 6.5 mg/kg E. coli LPS i.v., which resulted in 50% survival. In the hemorrhagic shock protocol, rats were maintained for 3 h at 40 mm Hg mean arterial pressure, and survival during a 24-h observation period was 40%. LPS injection and hemorrhage caused rapid neutropenia in survivors and nonsurvivors. Low circulating PMN counts persisted during hypotension in the hemorrhagic protocol and among nonsurvivors in the LPS protocol, but in both protocols a tendency toward significantly higher circulating PMN counts in survivors compared with nonsurvivors was found. In both protocols, survivors had significantly lower fractions of circulating activated PMNs and lower adhesion of circulating PMNs to nylon fibers. In the LPS protocol, higher plasma TNF activity was found in nonsurvivors than in survivors, but no TNF activity in plasma could be found throughout the hemorrhagic protocol. These results indicate that nonsurvivors in both shock models exhibit higher levels of PMN activation. No correlation was detected between PMN activation and plasma TNF activity to suggest that TNF serves as the primary mediator of circulating PMN activation. |
| 1995 | The effect of soluble tumor necrosis factor receptor-II on endotoxin-mediated hemodynamic instability. | J Surg Res | Tumor necrosis factor-alpha (TNF-alpha), a central mediator in the hemodynamic response to injury and infection, is a primary mediator of endotoxin-induced hemodynamic instability. Two types of naturally occurring soluble TNF receptors circulate in human experimental endotoxemia and the recombinant proteins of both have been hypothesized as potential therapeutic agents antagonizing TNF-mediated effects of endotoxemia. The administration of recombinant sTNFr-I has been previously shown to attenuate the hemodynamic collapse of lethal bacteremia. In the current study, we investigated the role of recombinant sTNFR-II at low (0.5 mg/kg) and high (2.5 mg/kg) doses as a potential therapeutic agent for the inhibition of endotoxin lipopolysaccharide (LPS)-mediated hemodynamic instability. Eighteen male Sprague-Dawley rats were anesthetized and cannulated for continuous blood pressure monitoring and cardiac output measurement by thermodilution. Groups of animals received saline, LPS (1 mg/kg), or sTNFr-II (at 0.5 or 2.5 mg/kg) 15 min prior to LPS (1 mg/kg). Hemodynamic variables (blood pressure, cardiac output, heart rate) were monitored every 15 min for 2 hr. LPS caused a 30% decrease in mean arterial pressure by 60 min, which began to recover by 120 min. sTNFr-II was unable to prevent LPS-induced hypotension at low or high dose. Serum levels of immunoreactive TNF-alpha, undetectable in control animals, were significantly increased by sTNFr-II compared to LPS alone. Serum from animals treated with high-dose sTNFr-II showed significantly less TNF cytotoxicity than those treated with low-dose sTNFr-II, indicating that high doses of sTNFr-II are required for the inhibition of the bioactivity of TNF.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1995 | Cytokine levels and systemic toxicity in patients undergoing isolated limb perfusion with high-dose tumor necrosis factor, interferon gamma, and melphalan. | J Clin Oncol | Isolated limb perfusion (ILP) with tumor necrosis factor (TNF), interferon gamma, and melphalan (M) has been reported to result in high response rates for extremity melanoma and sarcoma. We have evaluated the relationship of systemic TNF exposure to induction of several secondary mediators and incidence of systemic toxicity.Nineteen patients with extremity melanoma (n = 16) or sarcoma (n = 3), underwent 90-minute ILP with TNF-alpha, interferon gamma (0.2 mg), and M (10 to 13 mg/L of limb volume) (TNF/IFN/M) (n = 12), or M alone (n = 7). Continuous intraoperative monitoring (CIM) for systemic leak from the perfusion circuit was performed using radioactive iodine-131 albumin. Cytokine levels in the perfusate and systemic circulation during and after ILP were measured by enzyme-linked immunosorbent assay.Systemic leaks > or = 1% from the perfusion circuit occurred in six patients who received TNF/IFN/M and in four who received M alone. Hypotension that required vasopressor support occurred in six of six patients with evidence of a leak (> or = 1%) and zero of six patients without a leak (< 1%). These six patients had significantly higher peak systemic TNF levels during and after perfusion than patients without a leak (2.8 and 8.2 ng/mL v 0.7 and 2.0 ng/mL, respectively; P < .05). All patients who received TNF/IFN/M had significantly greater increases in systemic interleukin-6 (IL-6) levels than in patients with M alone (12,395 +/- 10,374 pg/mL v 79.4 +/- 7.2 pg/mL, respectively; P < .001). Intracellular adhesion molecule (ICAM), IL-8, and TNF-R levels were also increased after ILP with TNF/IFN/M.ILP with TNF/IFN/M can be safely performed, as I131 albumin provides a sensitive measure of systemic leakage from the perfusion circuit. Patients with a measured leak of > or = 1% develop mild and transient postoperative hypotension with significantly higher systemic TNF levels and lower perfusate TNF levels than in patients without leaks. |
| 1995 | Hemodynamic evaluation of recombinant human tumor necrosis factor (TNF)-alpha, TNF-SAM2 and liposomal TNF-SAM2 in an anesthetized dog model. | J Immunother Emphasis Tumor Immunol | We have evaluated the hemodynamic effects of systemically administered recombinant human tumor necrosis factor (TNF)-alpha, TNF-SAM2 and liposome-bound TNF-SAM2 in an anesthetized mongrel dog model. A dose of 10 micrograms TNF protein/kg of each formulation was injected in a peripheral vein and mean systemic arterial pressure (SAP), heart rate (HR) and cardiac output (CO) were measured. TNF-alpha induced a marked drop in SAP in all three dogs (mean decrease = 59.3 +/- 5.2 mm Hg; to 61.5% of baseline; p = 0.008); whereas TNF-SAM2 caused a smaller and transient drop in SAP in four dogs (mean decrease = 25.5 +/- 10.1 mm Hg; to 81.2% of baseline; p = 0.086). In three dogs administered liposome-bound TNF-SAM2, which retains antitumor activity in vivo, a net slight hypertensive phase and sustained elevated CO occurred, followed by a return to an essentially normotensive state (101.0% of baseline SAP). This model demonstrates that the principal acute systemic toxicity of TNF, i.e., hypotension, can be markedly attenuated by liposomal formulation of a second-generation TNF. |
| 1994 | Participation of tumour necrosis factor and nitric oxide in the mediation of vascular dysfunction in splanchnic artery occlusion shock. | Br J Pharmacol | 1. Splanchnic artery occlusion (SAO) shock is characterized by irreversible circulatory failure. Tumour necrosis factor (TNF-alpha) may affect the L-arginine/nitric oxide (NO) pathway, thus contributing to the cardiovascular derangements of circulatory shock. 2. We investigated the contribution of both TNF-alpha and the L-arginine/nitric oxide pathway to the vascular dysfunction of SAO shock. Anaesthetized rats, subjected to total occlusion of the superior mesenteric artery and the coeliac trunk for 45 min developed a severe shock state (SAO shock) resulting in a fatal outcome within 75-90 min after the release of occlusion. Sham operated animals were used as controls. SAO shocked rats had also a marked hypotension and enhanced macrophage and serum levels of TNF-alpha. Furthermore, aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE 1 nM-10 microM) and reduced responsiveness to acetylcholine (ACh 10 nM-10 microM). Endothelium-denuded aortic rings had also a marked hyporeactivity to phenylephrine, which was restored to control values by in vitro administration of NG nitro-L-arginine-methyl ester (L-NAME 10 microM). 3. In vivo administration of cloricromene (2 mg kg-1, i.v.), an inhibitor of TNF-alpha biosynthesis, increased survival, enhanced mean arterial blood pressure and reduced macrophage and serum levels of TNF-alpha. Furthermore, aortic rings from shocked rats treated with cloricromene exhibited a greater contractile response to phenylephrine and improved responsiveness to ACh when compared to aortic rings from vehicle-treated SAO shocked rats. 4. Our results suggest that TNF-alpha alters both endothelial and muscular L-arginine/nitric oxide pathways which in turn produce vascular dysfunction in SAO shock. |
| 1994 | PAF and TNF increase the precursor of NF-kappa B p50 mRNA in mouse intestine: quantitative analysis by competitive PCR. | Biochim Biophys Acta | NF-kappa B, a nuclear transcription factor, is involved in the regulation of inflammatory cytokines. We have previously reported that PAF and TNF induce intestinal injury in rats and mice and the interaction of TNF and PAF probably plays a central role in its pathogenesis. In the present study, we developed a competitive PCR method to quantitate the transcripts of NF-kappa B p50/p105 gene, and investigated the effects of PAF and TNF on p50/p105 gene expression in the small intestine of C3H/HeN mice - p105 is the precursor of the p50 subunit of NF-kB. We found that NF-kappa B p50/p105 gene is constitutively expressed in the normal small intestine in small quantities (7.05 +/- 1.04 attomol/micrograms total RNA). PAF at a dose (1 microgram/kg) causing no systemic changes (e.g., hypotension, hemoconcentration), markedly increased intestinal p50/p105 transcripts within 30 min. TNF, at dose (1 mg/kg) also insufficient to induce systemic changes, increased intestinal p50/p105 gene expression, although its effect was much slower than PAF. The effect of TNF was not blocked by WEB 2086, a PAF antagonist. Our results indicate that both PAF and TNF stimulate the expression of NF-kappa B p50/p105 in vivo. However, the mechanisms of their respective actions are probably different. |
| 1994 | Protection against rat endotoxic shock by p55 tumor necrosis factor (TNF) receptor immunoadhesin: comparison with anti-TNF monoclonal antibody. | J Infect Dis | The protective efficacy of a p55 tumor necrosis factor receptor immunoadhesin (TNFR-IgG) was compared with that of an anti-TNF monoclonal antibody (MAb) in a rat endotoxic shock model. TNFR-IgG (5 mg/kg), given 30 min before endotoxin (LPS), attenuated LPS induction of hypotension and tachycardia and eliminated LPS induction of serum TNF activity. In contrast, anti-TNF MAb (5 mg/kg) had little effect on LPS-induced hemodynamic changes and neutralized only partially the excessive serum TNF activity. The 6-day survival was 1 of 10 controls; 6 of 11, 5 of 7, and 8 of 9 rats receiving 0.2, 1.0, or 5.0 mg/kg TNFR-IgG, respectively; and 3 of 8 rats receiving 5 mg/kg anti-TNF MAb. These results indicate that TNFR-IgG is more potent than anti-TNF MAb at neutralizing excessive TNF activity in vivo. |
| 1994 | Effects of TNF-alpha on hemodynamic changes and circulating endothelium-derived vasoactive factors in dogs. | Am J Physiol | To elucidate the relation of tumor necrosis factor-alpha (TNF-alpha)-induced hemodynamic change to endothelium-derived vasoactive factors, we simultaneously measured hemodynamic parameters and circulating endothelin (ET)-1, ET-3, nitrite/nitrate (NOx), and 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) in anesthetized dogs following administration of TNF-alpha with or without NG-nitro-L-arginine (L-NNA), a nitric oxide (NO) synthase inhibitor, and indomethacin, a cyclooxygenase inhibitor. Natural human TNF-alpha (10 micrograms/kg, n = 5) with or without L-NNA (1 mg/kg, n = 5) or indomethacin (2 mg/kg, n = 5) was administered intravenously as a bolus, while administration of vehicle served as control (n = 5). After administration of TNF-alpha, mean arterial pressure and cardiac index significantly decreased, whereas systemic (SVRI) and pulmonary (PVRI) vascular resistance index increased. Plasma levels of ET-1, ET-3, NOx, and 6-keto-PGF1 alpha significantly (P < 0.01) increased at 1 h. L-NNA or indomethacin blocked TNF-alpha-induced hypotension and remarkably increased SVRI but did not affect decreased cardiac index. Our data suggest that endogenous ET-1 may partly contribute to TNF-alpha-induced increases in SVRI and PVRI, against which ET-3, NO, and prostacyclin may function as compensatory vasodilators. |
| 1994 | Therapy with antibody to tumor necrosis factor against endotoxin shock in rabbits. | J Anesth | The purpose of this study was to determine the efficacy of treatment with anti-tumor necrosis factor (TNF) antibody in preventing the deleterious effects of endotoxin. Polyclonal anti-TNF antibody was produced by immunizing rabbits. Experiments were carried out on 16 rabbits intravenously infused with the lethal dose of lipopolysaccharide (LPS). Pretreatment with anti-TNF antibody resulted in protection from the development of hypotension and metabolic acidosis. The serum TNF level was significantly depressed in the antibody-pretreated group. Eighty-eight percent in the anti-TNF antibody-pretreated rabbits survived more than 48 h, whereas none of the rabbits who were given LPS alone survived over 24 h (LPS group). Prominent histopathological changes in the liver and kidney were evident in the LPS group. In contrast, pathologic changes in the tissue from the anti-TNF antibody group were considerably less prominent. These results support the idea that TNF plays a central role in mediating the pathophysiologic changes during endotoxin shock. |
| 1994 | Platelet-activating factor and endotoxin induce tumour necrosis factor gene expression in rat intestine and liver. | Immunology | We have shown previously that endotoxin, tumour necrosis factor (TNF) and platelet-activating factor (PAF) are important in the pathogenesis of bowel injury, and that endotoxin and TNF induce PAF formation in bowel tissue. In the present study we investigated the effects of endotoxin and PAF on TNF gene expression. Adult rats were injected with endotoxin (2 mg/kg), PAF (1 microgram/kg) or endotoxin plus PAF, and were killed after 30 min. Endotoxin had little systemic effect. PAF induced transient hypotension and mild bowel injury. Endotoxin plus PAF caused profound shock, severe haemoconcentration, leukopenia and intestinal necrosis. Sham-operated rats had barely detectable TNF mRNA in the liver or intestine. Endotoxin or PAF induced a marked increase in TNF mRNA, especially in the distal ileum and in the liver, but much less in the jejunum. Endotoxin plus PAF did not further increase TNF mRNA, probably due to development of tissue injury. Serum TNF levels in animals treated with endotoxin, PAF and endotoxin plus PAF were elevated. Endotoxin induces TNF gene expression probably via both PAF-dependent and PAF-independent pathways, since TNF mRNA formation was only partially blocked by PAF antagonist. |
| Protective effects of BAY U 3405, a thromboxane A2 receptor antagonist, in endotoxin shock. | Pharmacol Res | The present study was designed to investigate the effects of BAY U 3405, a new thromboxane A2 (TxA2) receptor antagonist, in endotoxin shock. Endotoxin shock (ES) was induced in male rats by an i.v. injection of Salmonella enteritidis lipopolysaccharide (LPS; 20 mg kg-1). LPS administration caused animal death (survival = 0%, 48 h after endotoxin challenge), systemic hypotension, depressed phagocytosis and increased blood levels of TNF-alpha, TxB2 and 6-keto-PGF1 alpha, reduced white blood cell (WBC) count (ES = 5.9 +/- 1 x 10(3) mm-3; CTRL = 13.4 +/- 5 x 10(3) mm-3) and enhanced myeloperoxidase (MPO) activity, studied as a quantitative means for assessing leukocyte accumulation, in the ileum (ES = 0.24 +/- 0.7 U g-1 fresh tissue; CTRL = 0.13 +/- 0.04 U g-1 fresh tissue), in the heart (ES = 0.41 +/- 0.1 U g-1 fresh tissue; CTRL = 0.16 +/- 0.08 U g-1 fresh tissue) and in the lung (ES = 0.68 +/- 0.11 U g-1 fresh tissue; CTRL = 0.19 +/- 0.05 U g-1 fresh tissue). Furthermore, endotoxin administration produced characteristic damage of the gastric mucosa consisting of haemmorrhagic infiltrates. BAY U 3405 (30 mg kg-1 i.v., 30 min before endotoxin challenge) increased survival rate (45% survival rate 48 h after endotoxin challenge), reduced hypotension, decreased TNF-alpha levels in serum, enhanced phagocytic activity (ES = 25.6 +/- 1.9%, BAY U 3405 = 45.9 +/- 0.4%, P < 0.001) and lowered MPO activity in the ileum (0.14 +/- 0.05 U g-1 fresh tissue), in the heart (0.18 +/- 0.08 U g-1 fresh tissue) and in the lung (0.44 +/- 0.09 U g-1 fresh tissue). Finally, the gastric alterations were significantly reduced in rats pretreated with BAY U 3405. These data suggest that this thromboxane receptor antagonist might be a useful drug in shock conditions. |
| 1994 | Phase I study of tumor necrosis factor-alpha and actinomycin D in pediatric patients with cancer: a Children's Cancer Group study. | J Immunother Emphasis Tumor Immunol | In preclinical studies, synergy was observed between tumor necrosis factor-alpha (TNF-alpha) and agents that interact with DNA topoisomerase II, such as actinomycin D (Act D). Based upon this, a Phase I study was conducted in pediatric patients utilizing an escalating dose of recombinant TNF (rTNF) in combination with a fixed dose of Act D. Act D (15 micrograms/kg/day) was administered daily by intravenous push immediately followed by intravenous rTNF daily for 5 consecutive days. Thirty-three patients with refractory malignancies were entered in the study, of whom 28 patients could be evaluated for toxicity. Malignancies included sarcomas (16), Wilms' tumor (6), leukemias (3), and others (3). The starting dose for rTNF was 40 micrograms/m2/day x 5 and was escalated in subsequent patient groups until nonhematopoietic, dose-limiting toxicity occurred. At 240 micrograms/m2/day of rTNF, three of six patients experienced grade 4 toxicity consisting of hypotension, hemorrhagic gastritis, and renal and liver biochemical abnormalities. Evidence of antitumor response was observed in two patients: one with metastatic Ewing's sarcoma and one with Wilms' tumor. We conclude that the maximum tolerated dose of rTNF when combined with Act D is between 200 and 220 micrograms/m2/day x 5 for pediatric patients. |
| Recombinant human tumor necrosis factor causes regression in patients with advanced malignancies. | Oncology | Fifteen patients with advanced solid tumors of various types were treated by the intratumoral administration of recombinant human tumor necrosis factor (rH-TNF). The treatment appeared to benefit the 4 cases of superficial tumors: there were 1 complete response, 1 partial response and 2 minor responses. In all 11 patients with deep-seated tumors, including 6 cases of pancreatic cancer, 4 of liver cell cancer and 1 of metastatic liver tumor, no tumor regression was observed, but progression stopped in all these tumors. Seven of the 11 with deep-seated tumors showed a decrease in tumor markers and/or the development of tumor necrosis. Fever, hypotension and fatigue were the main clinical side effects. No significant changes were found in hematologic, renal or liver parameters. These results suggest that administration of rH-TNF to the tumor site has the potential for controlling local tumor growth. |
| Protective effects of a monoclonal antibody against lipid A in endotoxic shock. | Methods Find Exp Clin Pharmacol | Bacterial lipopolysaccharide given intravenously at 30 mg/kg to anesthetized rats results in rapid systemic hypotension and hypovolemia, elaboration of cytokines, increased proteolysis and vascular endothelial dysfunction. When a monoclonal antibody SdJ5-1.17.15 (SdJ5) directed against the lipid A moiety of lipopolysaccharide was administered at (1.25 or 5.0 mg/kg) 5 min prior to the endotoxin, significant protection was afforded to rats. This protection was manifested by a significant reduction in the early hypotension, as well as attenuation of hypovolemia and proteolysis. To evaluate endothelial function, superior mesenteric artery rings were isolated from endotoxemic rats 4 h after endotoxic challenge. Lipopolysaccharide (LPS) significantly reduced superior mesenteric artery vasorelaxation to acetylcholine and A23187, two endothelium-dependent vasodilators, but not to NaNO2, an endothelium-independent vasodilator. SdJ5 significantly preserved vasorelaxation responses to both acetylcholine and A23187, indicating a marked degree of endothelial preservation by this anti-lipid A monoclonal antibody. The protection was dose-dependent since 0.3 mg/kg of SdJ5 did not provide significant protection in any variable measured. Moreover, there was no significant difference between the 1.25 mg/kg and 5.0 mg/kg dose of SdJ5. Furthermore, plasma concentrations of TNF-alpha, a cytokine involved in mediating many of the effects associated with endotoxemia, was significantly reduced in SdJ5-treated animals. Thus, SdJ5 appears to be capable of counteracting many of the in vivo sequelae of endotoxemia in rats. |
| 1994 | [The role tumor necrosis factor in multiple organ dysfunction caused by bowel ischemia and reperfusion]. | Zhonghua Zheng Xing Shao Shang Wai Ke Za Zhi | To explore the role of tumor necrosis factor (TNF) in the pathogenesis of multiple organ dysfunction following bowel ischemia and reperfusion, 98 rats were subjected to occlusion of the superior mesenteric artery for 45 minutes. It was found that the plasma TNF level increased rapidly after release of the clamp, peaking to 27.59 +/- 11.13 ng/ml 2 hours after reperfusion. Its changes in quantity was directly related to endotoxin in the portal circulation. Furthermore, the results showed that pretreatment with monoclonal antibody to TNF-alpha could significantly lowered the plasma TNF content and notably improved the functions of various organs. This study demonstrated that release of TNF might result in systemic hypotension and remarkable damage to liver, kidneys and lungs, which contributed to the development of sepsis and multiple system organ failure following severe ischemia-reperfusion injury of the intestine. |
| Preliminary study on modulation of the biological effects of tumor necrosis factor-alpha in advanced cancer patients by the pineal hormone melatonin. | J Biol Regul Homeost Agents | Previous experimental studies have suggested the possibility to modulate the biological activity and toxicity of cytokines by immunomodulating neurohormones. In particular, the pineal hormone melatonin (MLT) has been proven to amplify the immune effects of IL-2 and to reduce its toxicity. On this basis, we decided to investigate the effect of MLT on biological activity and toxicity of another important antitumor cytokine, TNF. The study was performed in 14 metastatic solid tumor patients, for whom no effective standard antitumor therapy was available. Informed consent was previously obtained from each patient. Patients were randomized to be treated with TNF or TNF plus MLT. Recombinant human TNF was given at a daily dose of 0.75 mg intravenously for 5 consecutive days. MLT was given orally at a daily dose of 40 mg, starting 7 days before TNF. Lymphocyte mean number observed at the end of TNF infusion was significantly higher in patients treated with TNF plus MLT than in those receiving TNF alone. On the contrary, no significant difference occurred in hemoglobin, platelet and neutrophil mean values. Asthenia and hypotension were significantly less frequent in patients treated with TNF plus MLT, whereas no difference occurred in the frequency of fever and chills. Even though limited to a small number of patients, this preliminary study would suggest the possibility to modulate TNF toxicity and biological activity by a concomitant treatment with the pineal hormone MLT. |
| 1994 | Tumor necrosis factor causes microvascular protein leakage independently of neutrophils or mast cells. | J Surg Res | Tumor necrosis factor-alpha (TNF-alpha) has been implicated as an important mediator in the development of multiple system organ failure after either severe injury or infection. Using the rat cremaster muscle, we previously showed that systemically administered TNF-alpha caused hypotension, tachypnea, and microvascular protein leakage in association with leukocyte-endothelial adherence. In the current study, we hypothesized that topical administration of TNF-alpha to the cremaster muscle would cause microvascular protein leakage independent of changes in hemodynamic parameters. In addition, histological methods were used to study the role of neutrophils and mast cells in the TNF-alpha-induced microvascular protein leakage. Topically applied low-dose (1 ng/ml) TNF-alpha caused microvascular leakage in the cremaster, without changes in central hemodynamic parameters, but high-dose TNF-alpha (10 ng/ml) did not cause protein leakage. Histological studies did not demonstrate evidence of either neutrophil adhesion or mast cell degranulation in topically applied TNF-alpha-treated cremasters compared to controls. These data suggest that TNF-alpha-induced macromolecular leakage is a dose-dependent phenomenon which can occur independently of neutrophils or mast cell degranulation. |
| 1994 | Selected treatment strategies for septic shock based on proposed mechanisms of pathogenesis. | Ann Intern Med | To review selected new therapies for septic shock designed to inhibit bacterial toxins or endogenous mediators of inflammation.Scientific journals, scientific meeting proceedings, and Food and Drug Administration advisory committee proceedings.Preclinical and clinical data from trials using core-directed antiendotoxin antibodies and anticytokine therapies for sepsis and studies in animal models of sepsis from our laboratory.Ten clinical trials using core-directed antiendotoxin antibodies produced inconsistent results and did not conclusively establish the safety or benefit of this approach. Both anti-interleukin-1 and anti-tumor necrosis factor (TNF) therapies have been beneficial in some animal models of sepsis but did not clearly improve survival in initial human trials, and one anti-TNF therapy actually produced harm. Neutrophils, another target for therapeutic intervention, protect the host from infection but may also contribute to the development of tissue injury during sepsis. In a canine model of septic shock, granulocyte colony-stimulating factor increased the number of circulating neutrophils and improved survival, but an anti-integrin (CD11/18) antibody that inhibits neutrophil function worsened outcome. Nitric oxide, a vasodilator produced by the host, causes hypotension during septic shock but may also protect the endothelium and maintain organ blood flow. In dogs challenged with endotoxin, the inhibition of nitric oxide production decreased cardiac index and did not improve survival.No new therapy for sepsis has shown clinical efficacy. Perhaps more accurate clinical and laboratory predictors are needed to identify patients who may benefit from a given treatment strategy. On the other hand, the therapeutic premises may be flawed. Targeting a single microbial toxin such as endotoxin may not represent a viable strategy for treating a complex inflammatory response to diverse gram-negative bacteria. Similarly, the strategy of inhibiting the host inflammatory response may not be beneficial because immune cells and cytokines play both pathogenic and protective roles. Finally, our scientific knowledge of the complex timing of mediator release and balance during sepsis may be insufficient to develop successful therapeutic interventions for this syndrome. |
| 1994 | Drug modulation of antigen-induced paw oedema in guinea-pigs: effects of lipopolysaccharide, tumour necrosis factor and leucocyte depletion. | Br J Pharmacol | 1. In guinea-pigs previously sensitized with ovalbumin, the intra-plantar administration of the antigen induced dose-dependent and sustained oedema. An intense infiltrate of neutrophils and eosinophils was observed at the peak of the oedema (4 h). 2. Oedema induced by ovalbumin at the doses of 50 or 200 micrograms/paw was not inhibited by antihistamines (meclizine and cetirizine), a PAF antagonist (BN 50730), a cyclo-oxygenase inhibitor (indomethacin), a lipoxygenase inhibitor (MK-886), a dual type lipo- and cyclo-oxygenase inhibitor (NDGA), a bradykinin antagonist (Hoe 140) or the combination of cetirizine, MK-886, indomethacin and BN 50730. These drugs did inhibit paw oedema induced by their specific agonists or by carrageenin. These results suggest that histamine, PAF, prostaglandins, leukotrienes or bradykinin are not important in the development of immune paw oedema in guinea-pigs. 3. Dexamethasone (10 mg kg-1) inhibited oedema induced by ovalbumin (50 or 200 micrograms/paw, P < 0.05). This effect apparently does not result from inhibition of arachidonate metabolism, since indomethacin, MK-886 and NDGA were without effect. 4. Oedema induced by ovalbumin (50 or 200 micrograms/paw) was also inhibited by azelastine. This effect was not due to the anti-histaminic property of azelastine since two other potent-antihistamines, meclizine and cetirizine, were ineffective. 5. Intravenous injection of lipopolysaccharide (LPS) dose-dependently inhibited the oedema induced by ovalbumin (200 micrograms/paw). This effect could not be attributed to hypotension or leucopenia since the maximal dose applied (81 micrograms kg-1) did not induce significant changes in the blood pressure or in the white blood cell levels of the animals. It is suggested that the effect of LPS is mediated by the endogenous release of cytokines, including tumour necrosis factor (TNF alpha). Murine TNF alpha dose dependently(9-81 microg kg-1) inhibited the paw oedema induced by ovalbumin.7. The anti-oedematogenic effects of LPS and/or TNF alpha are possibly associated with their capacity to inhibit leucocyte emigration. Accordingly, guinea-pigs rendered leucopenic with vinblastine exhibited less intense oedema after ovalbumin. Vinblastine did not affect oedema induced by PAF or bradykinin,indicating that vascular responsiveness was not involved. |
| 1994 | Release of endothelin in relation to tumor necrosis factor-alpha in porcine Pseudomonas aeruginosa-induced septic shock. | Shock | Septic shock is characterized by surges of tumor necrosis factor-alpha (TNF-alpha) along with myocardial dysfunction and systemic hypotension. TNF-alpha promotes the release of immunoreactive endothelin (ET). Because TNF-alpha is elevated in septic shock, we hypothesized that elevated levels of endothelin can contribute to cardiac dysfunction and hypotension. We infused live Pseudomonas aeruginosa into anesthetized, hemodynamically monitored young swine and measured ET and TNF-alpha. Septic swine developed systemic arterial hypotension and had significantly elevated TNF-alpha (4.15 +/- .41 U/ml at 1 h versus .40 +/- .13 U/ml at time zero) compared to control animals. ET levels were significantly elevated at 4 h (52.38 +/- 12.88 pg/ml vs. 10.45 +/- 1.82 pg/ml at time zero) and correlated negatively with the decline in cardiac output. We then passively immunized swine using anti TNF-alpha prior to the induction of sepsis to examine if TNF played a central role in the release ET. The anti TNF-alpha effectively removed circulating TNF-alpha bioactivity in septic animals. Anti-TNF-alpha-treated animals did not develop significant systemic arterial hypotension and had significant attenuation in endothelin (19.01 +/- 4.18 pg/ml at 4 h compared to 52.38 +/- 12.88 pg/ml in septic animals at 4 h) which correlated with preservation of cardiac output. TNF-alpha may cause cardiac dysfunction in sepsis syndrome through increased release of ET. |
| 1994 | Role of tumor necrosis factor-alpha in acute hypovolemic hemorrhagic shock in rats. | Am J Physiol | Hemorrhagic shock was induced in male anesthetized rats by intermittently withdrawing blood from an iliac catheter until mean arterial blood pressure (MAP) fell and stabilized within the range of 20-30 mmHg. Survival rate, MAP, and serum and macrophage levels of tumor necrosis factor-alpha (TNF-alpha) were then evaluated. Furthermore, in ex vivo studies, the responsiveness to phenylephrine (PE; 1 nM to 10 microM) was investigated in aortic rings from hemorrhagic shocked rats. Antibodies raised against TNF-alpha (anti-TNF-alpha; 2 mg/kg) or vehicle (phosphate-buffered saline, 1 ml/kg) were injected intravenously 3 h before the bleeding. Vehicle-treated rats, subjected to hemorrhagic shock, exhibited acute and serious hypotension (MAP = 20-30 mmHg) and high levels of serum (790 +/- 47 pg/ml) and macrophage (78 +/- 9 pg/ml) TNF-alpha and died within 30 min. Moreover, aortas from shocked rats showed a marked hypocontractility to PE compared with the reactivity of aortas from a group of sham shocked rats. Anti-TNF-alpha administration significantly improved survival rate and MAP in hypovolemic shocked rats. Furthermore, the hyporesponsiveness to PE was significantly restored in aortic rings. Therefore, these data suggest that TNF-alpha is an important mediator in the pathophysiology of hypovolemic hemorrhagic shock and it might be responsible, at least in part, for the vascular hyporeactivity of this experimental circulatory shock. |
| 1994 | A human tumor necrosis factor (TNF) alpha mutant that binds exclusively to the p55 TNF receptor produces toxicity in the baboon. | J Exp Med | A number of recent studies have demonstrated that cellular responses to tumor necrosis factor (TNF) mediated by the p55 and the p75 TNF receptors are distinct. To evaluate the relative in vivo toxicities of wild-type TNF alpha (wtTNF alpha) and a novel p55 TNF selective receptor agonist, healthy, anesthetized baboons (Papio sp.) were infused with a near-lethal dose of either wtTNF alpha or a TNF alpha double mutant (dmTNF alpha) that binds specifically to the p55, but not to the p75, TNF receptor. Both wtTNF alpha and dmTNF alpha produced comparable acute hypotension, tachycardia, increased plasma lactate, and organ dysfunction in Papio. However, administration of wtTNF alpha produced a marked granulocytosis and loss of granulocyte TNF receptors, whereas little if any changes in neutrophil number or cell surface TNF receptor density were seen after dmTNF alpha mutant administration. Infusion of dmTNF alpha resulted in a plasma endogenous TNF alpha response that peaked after 90-120 min. We conclude that selective p55 TNF receptor activation is associated with early hemodynamic changes and the autocrine release of endogenous TNF alpha. Significant systemic toxicity results from p55 TNF receptor activation, but the role of the p75 TNF receptor in systemic TNF toxicity requires further study. |
| 1994 | Association between biosynthesis of nitric oxide and changes in immunological and vascular parameters in patients treated with interleukin-2. | Eur J Clin Invest | Hypotension is a dose-limiting side effect of interleukin-2 (IL-2) therapy. This may be due to increased biosynthesis of the potent vasodilator nitric oxide (NO) induced by cytokines such as tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), which are known to be generated during IL-2 therapy. We describe the relationship between NO biosynthesis and changes in immunological and vascular parameters during IL-2 therapy in 13 patients with metastatic cancer. Plasma concentrations of neopterin and nitrite plus nitrate (NOx) were higher in cancer patients prior to treatment compared with normal subjects (neopterin; 10.8 +/- 1.4 vs. 2.0 +/- 0.4 ng ml-1, P < 0.001: NOx; 45 +/- 6 vs. 28 +/- 2 microM, P < 0.005). Pretreatment TNF-alpha and IFN-gamma plasma concentrations were not significantly different in cancer patients from those in controls. During infusion of IL-2 (18 x 10(6) international units m-2 per day for 5 days) these parameters increased, reaching maximal concentrations at day 3 for IFN-gamma and day 5 for TNF-alpha, neopterin and NOx. The maximal induced NOx correlated with maximal TNF-alpha (r = 0.60, P < 0.04), IFN-gamma (r = 0.63, P < 0.02) and neopterin (r = 0.66, P < 0.01). As plasma NOx concentrations increased, systolic blood pressure fell, reaching a minimum at day 3 despite a continued rise in NOx concentrations. These changes were accompanied by a continuous increase in pulse rate throughout the infusion period. These findings indicate that induction of NO biosynthesis contributes to hypotension induced during IL-2 therapy.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1994 | Interleukin-1 beta and tumor necrosis factor-alpha synergistically induce NO synthase in rat vascular smooth muscle cells. | Am J Physiol | Cytokine-inducible nitric oxide (NO) production has been implicated in the pathogenesis of septic shock. The present study was designed to determine which cytokines induce expression of the NO synthase gene in rat aortic vascular smooth muscle cells (VSMC) in vitro and whether NO synthase gene expression is inducible in vivo. NO synthase mRNA appeared after 4-h exposure to interleukin-1 beta (IL-1 beta), and levels continued to increase up to 24 h. Levels of NO synthase transcripts were greatest in VSMC treated with IL-1 beta (1 nM), lower in VSMC treated with Escherichia coli lipopolysaccharide (LPS; 100 micrograms/ml), and just detectable in VSMC treated with tumor necrosis factor-alpha (TNF-alpha; 1 nM). IL-1 beta, TNF-alpha, and LPS each induced NO synthase activity, assessed by release of nitrite, conversion of L-arginine to L-citrulline, and increased levels of guanosine 3',5'-cyclic monophosphate, whereas IL-2, IL-6, and interferon-gamma were ineffective. IL-1 beta was more potent and effective than TNF-alpha; however, submaximal concentrations of TNF-alpha acted synergistically with IL-1 beta to induce NO synthase gene expression and activity. Inducible NO synthase mRNA was present in aorta from rats 6 h after treatment with LPS (5 mg/kg), but not at 24 h. Synergistic activation of NO synthase gene expression in VSMC by IL-1 beta and TNF-alpha may contribute to hypotension in sepsis. |
| 1994 | Intraarterial combined immunochemotherapy for unresectable hepatocellular carcinoma: preliminary results. | Cancer Immunol Immunother | An important objective for patients with unresectable hepatocellular carcinoma (HCC) is the development of effective chemotherapy. We administered a combination of biological response modifiers and anticancer agents to 24 patients with unresectable HCC. Each case had an implanted infuser port which was connected to a catheter placed in the hepatic artery for the intraarterial (i.a.) administration of chemotherapy. The following agents were administered to each patient: recombinant interleukin-2 (800,000 JRU/day infused i.a. continuously for 6 days/week); OK-432 (5 KE injected i.a. twice in 4 weeks and i.m. three times per week); Adriamycin (10 mg injected i.a. twice in 4 weeks); cyclophosphamide (300 mg injected i.a. twice in 4 weeks), and famotidine (40 mg/day administered orally). Objective response was assessed according to tumor size measured by computed tomography and angiography before and after treatment. We observed a complete response (CR) in 4, partial response (PR) in 3, minor response (MR) in 7, no change (NC) in 7, and progressive disease (PD) in 3. The response rate (CR+PR+MR) was 58.3%. The overall 2-year survival rate was 52%. The 2-year survival rate of the responders (CR+PR+MR) was 80%, while that of the non-responders (NC+PD) was 0%. There was a significant difference between the responders and non-responders in respect to survival rate (P < 0.05). The percentages of CD25+ cells, CD56+ cells, and Leu7-CD16+ cells and NK activity in the peripheral blood showed a significant increase following the regimen. Serum levels of tumor necrosis factor alpha TNF alpha rose after the initiation of OK-432. TNF alpha levels were higher in the responders than in the non-responders. Adverse effects included high fever (all patients) and severe transient hypotension (15 patients) that was controlled by conservative therapy. Combined immunochemotherapy administered intraarterially may be a new strategy for treating unresectable HCC. |
| 1994 | Inhibition by all-trans-retinoic acid of tumor necrosis factor and nitric oxide production by peritoneal macrophages. | J Leukoc Biol | Besides their growth-inhibiting and differentiation-inducing properties, retinoids have been shown to exert immunomodulatory and anti-inflammatory functions by mechanisms that are not well understood. Tumor necrosis factor-alpha (TNF), a cytokine produced by mononuclear phagocytes, has been shown to be an important mediator of endotoxin-induced septic shock, cachexia, bone resorption, and inflammation. Nitric oxide may also have a role in septic shock, hypotension, and vasodilatation. In this study, we examined the effects of retinoids on the production of TNF and nitric oxide by murine peritoneal macrophages. Of the various retinoids studied, all-trans-retinoic acid (RA) was most potent; it almost completely inhibited the production of TNF by macrophages activated with endotoxin and interferon-gamma. The inhibitory effect was dependent on the dose and duration of RA exposure to macrophages. RA also blocked phorbol ester-induced TNF production in a macrophage cell line (RAW 264.7). Besides TNF, the retinoid suppressed the production of nitric oxide from activated peritoneal macrophages. The importance of these results in relation to controlling various harmful effects of cytokines released by activated macrophages is discussed. |
| 1994 | Biologic and clinical effects of continuous infusion interleukin-2 in patients with non-small cell lung cancer. | Cancer | Interleukin-2 (IL-2) has shown antitumor activity in some neoplasms, such as melanoma and renal carcinoma, but toxicity derived from bolus administration is significant, particularly at the cardiorespiratory level.To test feasibility, antitumor activity, pulmonary and systemic immunologic effects, and pulmonary function changes of continuous-infusion recombinant IL-2 given to patients with non-small cell lung cancer, eleven subjects with Stage III-IV disease were treated in a standard pulmonary medicine unit with a dose of 18 million IU/m2/day from day 1 to day 13 with 1-day rest on day 7. A second induction course was given after a 3-week rest. In patients with nonprogressive disease, four maintenance courses of 6 days' duration at the same dose were planned. Immunologic tests, including lymphocyte phenotype analysis and assays for the detection of tumor necrosis factor (TNF) and of anti-IL-2 antibodies, were performed before and after treatment in serum and bronchoalveolar lavage fluid (BAL). Cardiopulmonary function tests, including spirometry, arterial blood gas analysis, diffusion capacity, and echocardiography, were obtained before, during, and after treatment.Twenty-one cycles (15 induction courses plus 6 maintenance courses) were administered. No patient was able to complete the six planned courses, and only 3 patients entered the maintenance phase. Reasons for discontinuation included progressive disease in five cases, toxicity in three cases, and patient request in three cases. The most common side effects were fever, hypotension, oliguria, and elevated serum creatinine and liver enzyme levels. No patient required intubation or intensive care. No objective response was seen, and the median survival time was 10 months. Lymphocytosis and eosinophilia were observed in all patients. Surface marker analysis revealed a statistically significant increase in the percentage of CD3+, CD4+, CD25+ and DR+ cells in peripheral blood. Lymphoid cells derived from BAL disclosed an increased natural killer activity after IL-2 treatment, and TNF was increased in BAL fluid. Pulmonary function tests evidenced an increased alveolar-arterial difference for oxygen allied with a decrease of forced expiratory volume in 1 second, forced vital capacity, and carbon monoxide transfer coefficient consistent with a significant, albeit not clinically relevant, interstitial lung defect.Continuous-infusion IL-2 is feasible in patients with advanced lung cancer even outside an intensive care unit, but overall compliance is poor. Although clinical pulmonary toxicity is negligible, small but statistically significant alterations of the pulmonary function are evident. In addition, this regimen produces a significant activation of the immune system at the pulmonary level. |
| 1994 | Autoimmunity in human immunodeficiency virus infection and the use of thalidomide. | Panminerva Med | Although it is usually accepted that the pathogeny of HIV infection is related to the direct cytotoxic effect of the virus or indirectly by the invasion of T4 cells altering the T4/T8 ratio, clinical and serological and biochemical manifestations of the B cell polyclonal activation were described early in HIV infection epidemy. It is postulated that the central pathophysiologic mechanism in HIV infection is a high and inefficient production of interferon-gamma, genetically determined, leading to a production of autoantibodies that blocks the target organs even the immune system as well as a progressive interleukins levels increase, including tumor necrosis factor-alpha (TNF-alpha), responsible for many of the symptoms of these patients like fever, headache, fatigue, myalgia, hypotension, seizure and other neurological disorders, hematologic and hepatic disorders. Thalidomide reduces polyclonal hypergammaglobulinemia, that is associated with a clinical and laboratorial improvement, in a dose dependent manner as well as TNF-alpha levels. It seems that HIV infection is more a disease of abnormal host response triggered by HIV than an HIV disease. |
| 1994 | Correlation of serum cytokine and acute phase reactant levels with alterations in weight and serum albumin in patients receiving immunotherapy with recombinant IL-2. | Clin Exp Immunol | Recombinant IL-2 (rIL-2) has been used alone or in combination with other chemotherapeutic agents to enhance host defences against cancer. Prolonged administration of high doses, required for clinical efficacy, may precipitate serious dose-limiting toxicity. rIL-2-induced 'vascular leak syndrome' leads to hypotension, renal insufficiency, respiratory disturbances and other organ dysfunctions. Serial measurements of serum cytokines and the acute phase protein C-reactive protein (CRP) were performed on nine patients who received high-dose i.v. continuous therapy with rIL-2. The influence of these immunological parameters upon alterations in patients' weight and serum albumin, as indicators of toxicity, was assessed. All patients experienced weight increases during the cycle (3-11% of total body weight). The serum levels of tumour necrosis factor (TNF-alpha) and CRP were highly predictive of alterations in patients' weight (both P < 0.001), while no correlation was found with IL-6 and weight change. Serum albumin fell linearly throughout the infusion cycle, but this showed no correlation with variations in serum levels of IL-6, TNF-alpha, or CRP. The complement components C3 and C4 were significantly reduced at the end of the infusion, suggesting a possible role for this cascade system in mediating these clinical changes. The strong association between serum TNF-alpha and weight change, not previously documented, further supports the hypothesis that TNF-alpha is a key mediator in the pathogenesis of the 'vascular leak syndrome'. |
| 1994 | Delayed tumor necrosis factor alpha blockade attenuates pulmonary dysfunction and metabolic acidosis associated with experimental gram-negative sepsis. | Arch Surg | To ascertain the effect of delayed tumor necrosis factor alpha (TNF-alpha) on the evolution of systemic and pulmonary injury after the onset of sepsis.Prospective controlled trial.Anesthetized swine were made septic with a 1-hour infusion of live Pseudomonas aeruginosa, following which a treatment group received an infusion of anti-TNF-alpha monoclonal antibody (5 mg/kg). Control animals received 0.9% saline.Delayed anti-TNF-alpha treatment had no effect on septic pulmonary hypertension or decline in cardiac output. Late recovery in systemic arterial hypotension was associated with a reversal of arterial acidosis (P < .05 by t test and analysis of variance with Tukey's Studentized Range Test) compared with unprotected septic animals. Septic animals had a significant increase in mean (+/- SEM) plasma lactate levels at 5 hours compared with baseline values (3.8 +/- 0.7 vs 2 +/- 0.4, P < .05), but remained unchanged from baseline following anti-TNF-alpha treatment (1.5 +/- 0.1 vs 1.6 +/- 0.2, not significant). Characteristic septic neutropenia was dramatically reversed by anti-TNF-alpha treatment and was associated with downregulation (P < .05 by t test and analysis of variance) of polymorphonuclear neutrophil (PMN) leukocyte CD18 adhesion receptors and reduction (P < .05 by t test and analysis of variance) in lung PMN sequestration measured by myeloperoxidase activity. The mean (+/- SEM) decrease in bronchoalveolar lavage protein indicated an attenuated permeability injury in anti-TNF-alpha animals (septic animals at 5 hours compared with baseline value, 1044 +/- 270 vs 149 +/- 28 micrograms/mL; control animals at 5 hours compared with baseline value, 217 +/- 83 vs 129 +/- 19 micrograms/mL; P < .05 by t test and analysis of variance).These data show that delayed anti-TNF-alpha treatment reversed metabolic acidosis associated with sepsis. Furthermore, anti-TNF-alpha treatment reversed septic neutropenia, reduced PMN sequestration, and was associated with attenuated lung injury in a model of fulminant sepsis. This supports evidence of PMN-mediated tissue injury in sepsis and suggests mechanisms for potential therapeutic benefit of anti-TNF-alpha treatment in clinical practice. |
| 1994 | Liver-lung interactions during E. coli endotoxemia. TNF-alpha:leukotriene axis. | Am J Respir Crit Care Med | The liver modulates host responses to endotoxemia by production and clearance of tumor necrosis factor alpha (TNF-alpha) and eicosanoid lipoxygenation products. Reductions in liver blood flow (QL) are common during endotoxemia, but it is unknown whether the kinetics of TNF-alpha and leukotrienes (LTs) are thereby altered to amplify lung inflammation. To test this hypothesis, reductions in QL were modeled by an end-to-side portacaval shunt (PCS) in Sprague-Dawley rats. Conscious animals received 2.5 mg/kg of intravenous E. coli lipopolysaccharide (LPS) serotype 055:B5 (PCS + LPS; n = 17) or saline (n = 5). Responses were compared with those in sham-operated rats (sham + LPS; n = 13) and NSS-challenged control rats (n = 5). Cardiopulmonary changes, serum TNF-alpha, and formed elements were determined at t = 0, 1.5, 3.5, and 24 h, when organ wet/dry ratios (W/D) were measured with TNF-alpha, LTB4, and polymorphonuclear neutrophils (PMN) in bronchoalveolar lavage fluid (BALF). In PCS + LPS rats, mortality was 59% and serum TNF-alpha peaked at 1.5 h (2,784 +/- 658 U/ml, mean +/- SEM) coincident with the onset of hypotension. Despite equivalent endotoxemia and liver- and lung-associated TNF-alpha in sham + LPS rats at 1.5 h, peak serum TNF-alpha was 38% less and mortality was 15% (p < 0.05). Cardiac, hepatic, and cecal W/D were likewise increased in PCS + LPS versus sham + LPS rats, as were BALF PMNs (p < 0.05). In parallel studies, the disappearance kinetics of infused rTNF-alpha were not altered in nonendotoxemic PCS animals, implicating enhanced lung uptake of LPS and systemic export of TNF-alpha in PCS + LPS rats.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1994 | [Recombinant human tumor necrosis factor alpha (TNF): preclinical studies and results of early clinical trials]. | Acta Haematol Pol | The direct cytostatic and cytotoxic effect of recombinant human TNF alpha on human tumor xenografts encourages further clinical investigation. The most commonly observed toxicities (even after low doses), include constitutional symptoms, such as fever, chills, headache, hypotension and local inflammatory reaction at the injection point. Pharmacokinetic study has shown a rapid clearance following iv. infusion (half time 10-30 min). The phase I study has not revealed any beneficial effect so far (2-4% response), which may be due to low doses. Now the phase II investigations has started incorporating the combined application of TNF with other cytokines and cytostatics as well. The preliminary results seem to be promising. |
| 1994 | Interleukin 1 activates soluble guanylate cyclase in human vascular smooth muscle cells through a novel nitric oxide-independent pathway. | J Exp Med | Recent demonstration of cytokine-inducible production of nitric oxide (NO) in vascular smooth muscle cells (VSMC) from rat aorta has implicated VSMC-derived NO as a key mediator of hypotension in septic shock. Our studies to determine whether an inducible NO pathway exists in human VSMC have revealed a novel cytokine-inducible, NO-independent pathway of guanylate cyclase activation in VSMC from human saphenous vein (HSVSMC). Interleukin 1 (IL-1), tumor necrosis factor (TNF), interferon gamma (IFN-gamma) and Escherichia coli lipopolysaccharide (LPS) increased cGMP at 24 h, whereas IL-2 and IL-6 were ineffective. The effect of IL-1 on cyclic guanosine 3',5'-monophosphate (cGMP) was delayed, occurring after 6 h of exposure, and was maximal after 10 h. Methylene blue and LY83583 reversed the IL-1-induced increase in cGMP, suggesting that it was mediated by activation of soluble guanylate cyclase. However, IL-1-induced cGMP in HSVSMC was not inhibited by extracellular hemoglobin. Also, the effect of IL-1 on cGMP was not reversed by nitro- or methyl-substituted L-arginine analogs, aminoguanidine, or diphenyleneiodonium, all of which inhibit IL-1-induced NO synthase in rat aortic VSMC (RAVSMC). IL-1-induced cGMP in HSVSMC was also independent of tetrahydrobiopterin and extracellular L-arginine, as it was not affected by 2,4-diamino-6-hydroxyprytimidine, an inhibitor of tetrahydrobiopterin biosynthesis, and was similar in L-arginine-free and L-arginine-containing media. Analysis of NO synthase mRNA with the use of polymerase chain reaction indicates that levels of mRNA for inducible NO synthase are several orders of magnitude lower in IL-1-treated human HSVSMC than in IL-1-treated RAVSMC. IL-1-induced cGMP was also NO independent in human umbilical artery VSMC, and NO dependent in rat vena cava VSMC. Together these results indicate that IL-1 activates a novel NO-independent pathway of soluble guanylate cyclase activation in human VSMC. |
| 1993 | Phase I study of bryostatin 1: assessment of interleukin 6 and tumor necrosis factor alpha induction in vivo. The Cancer Research Campaign Phase I Committee. | J Natl Cancer Inst | Many oncogenes have been shown to code for growth factor receptors that are involved in regulation of cell growth and proliferation and can activate transcription via protein kinase C. Bryostatin 1, a partial agonist of protein kinase C, has demonstrated potent antitumor activity in vitro and in vivo in human tumor xenografts.The aim of this phase I study was to determine the optimal dosage and toxicity profile of bryostatin 1 and its influence on cytokine release in vivo.Three successive cohorts consisting of 35 patients with various malignant tumors were treated with bryostatin 1 by intravenous infusion over 1 hour as follows: cohort A--35 micrograms/m2 (three patients) or 50 micrograms/m2 (eight patients) once every 2 weeks; cohort B--25 micrograms/m2 once a week (eight patients); and cohort C--25 micrograms/m2 once a week for 3 weeks, with no treatment during the 4th week (16 patients). Plasma levels of tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) were measured by immunoradiometric assay and by radioimmunoassay, respectively.The dose-limiting toxicity was grade 3 or 4 myalgia in four of 11 patients in cohort A, in two of eight in cohort B, and in none of 16 in cohort C. Occurrence of myalgia was dose related. There was no significant myelosuppression, apart from a small and transient fall in platelet count. Six patients experienced acute but transient skin flushing, dyspnea, hypotension, and bradycardia, probably related to the bryostatin 1 vehicle. TNF-alpha and IL-6 were detected in plasma at 2 and 24 hours after treatment, respectively, and the levels were dose related (P = .02). Two patients with metastatic malignant melanoma had partial remission after three or four cycles of therapy; remission lasted 6 weeks and 10+ months, respectively.The dose-limiting toxicity of bryostatin 1 was myalgia. Plasma IL-6 and TNF-alpha concentrations were increased within 24 hours of therapy. Antitumor activity against malignant melanoma was observed early in the course of treatment.The recommended dosage of bryostatin 1 for phase II studies is 25 micrograms/m2 by intravenous infusion for 1 hour once a week for 3 weeks, with no treatment in the 4th week. IL-6 and TNF-alpha plasma concentrations may be useful in monitoring biological activity of bryostatin 1. Future studies should explore use of this drug with other conventional immune modulators and conventional cytotoxic drugs. |
| 1993 | [Inhibitory effect of mouse antiendotoxin monoclonal antibody (E5) on hypotension induced by endotoxin and TNF-alpha]. | Kansenshogaku Zasshi | Mouse anti-endotoxin monoclonal antibody (E5) is now under clinical trial (Phase II) in Japan by assessing clinical findings and plasma endotoxin levels. We attempted to evaluate an inhibitory effect of E5 on hypotension induced by endotoxin and TNF-alpha. Systolic blood pressure was measured with a programmable sphygmomanometer using the tail-cuff method. The mixture of endotoxin (E. coli O111:B4, Sigma, 2 micrograms/mouse) and recombinant mouse TNF-alpha (Genzyme, 8000 units) were injected into mice (ddY, 6-8-weeks-olds), and the change of blood pressure was observed for 3 hrs. The mixture significantly decreased the blood pressure to about 70% of the control. E5 (20 micrograms/mouse), which was injected 10 min before, significantly abrogated the effect of endotoxin and TNF-alpha. The hypotension induced by the mixture was definitely inhibited by the injection of E5 (50, 100 micrograms/mouse), injected 10 min later, or the injection of E5 (100 micrograms/mouse) 30 min later. We previously found that E5 prevents the lethality induced by a concomitant injection of endotoxin, TNF-alpha and IL-2. These results suggest that E5 effective for inhibition of endotoxin activity in vivo. |
| 1993 | Nitric oxide-releasing agents enhance cytokine-induced tumor necrosis factor synthesis in human mononuclear cells. | Biochem Biophys Res Commun | In septic shock tumor necrosis factor (TNF) leads to increased nitric oxide (NO) production by induction of NO synthase. An inverse regulatory effect, the influence of NO on cytokine synthesis, has rarely been investigated. The present study assessed the influence of NO-releasing agents on TNF production from interleukin-1 alpha (IL-1 alpha)-stimulated human peripheral blood mononuclear cells (PBMC). 3-Morpholino-sydnonimine (SIN-1) enhanced IL-1 alpha-induced TNF synthesis to a maximum of 272% (mean of n = 5 donors), with 100% set as TNF production by stimulation with IL-1 alpha alone. This finding was confirmed using another NO-donor, i.e., sodium nitroprusside (SNP). The effect was specific for TNF compared to the uninfluenced synthesis of IL-1 beta. Kinetic analysis showed the most pronounced increase in TNF synthesis when SIN-1 was added during the first 60 min after IL-1 alpha addition. These data reveal an enhancing effect of NO on cytokine-induced TNF synthesis. It may contribute to the regulation of TNF synthesis in pathological processes such as microbicidal activity, tumor cell lysis or endothelium-mediated hypotension. |
| 1993 | Age-related differences in responses to endotoxin infusion in unanesthetized piglets. | Circ Shock | Newborn endotoxic shock syndrome is associated with high morbidity and mortality, yet presents with different clinical manifestations than in older patients. To determine the influence of age on hemodynamic and metabolic responses to endotoxin, we developed a chronically instrumented endotoxic shock model using eight 1-3-day-old and seven 2-3-week-old piglets. Three days after surgery, 10 mg/kg of endotoxin was infused intravenously over 10 min in the younger group, and 5-10 mg/kg was given to the older animals. Two older piglets died immediately after infusion of 5 mg/kg of endotoxin, and five of the seven died within 4 hr, while all eight younger animals lived longer than 4 hr. Pulmonary artery pressure increased significantly after endotoxin in both groups, and there were no differences between groups. Systemic artery pressure and cardiac index fell by 44 +/- 10% and 70 +/- 15%, respectively, 5 min after endotoxin infusion in the older group, while these values did not change significantly in the younger group. Endotoxin infusion also caused greater elevation in pulmonary vascular resistance index in the older animals. In the later phase, which began 30 min after endotoxin, both groups displayed systemic hypotension and pulmonary hypertension, and the groups did not differ from one another in this regard. With progression of endotoxic shock, more severe metabolic acidosis developed in the older animals than in the younger animals. Plasma thromboxane B2 levels in the older group were about double those in younger piglets. Plasma 6-keto-PGF1 alpha and TNF alpha levels in both groups were similar and were significantly increased in the later phase.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1993 | Tumor necrosis factor alpha inhibits contractions to sympathetic nerve stimulation by a nitric oxide-dependent mechanism. | Proc Soc Exp Biol Med | Gram-negative sepsis and administration of tumor necrosis factor alpha (TNF alpha) are associated with hypotension and peripheral neuropathies suggestive of impaired sympathetic neurotransmission. We examined the effect of TNF alpha on the responses of the bovine pulmonary artery (BPA) to transmural sympathetic nerve stimulation (SNS). BPA contracted to SNS (0.5-32 Hz, 5-10 V, 2-msec duration, 2-msec delay) in a frequency-dependent manner. The contractions of the BPA to SNS were mediated by norepinephrine and activation of postsynaptic alpha 1-adrenoceptors, since they were attenuated by prazosin. Maximum contraction of the BPA to SNS was significantly enhanced (148 +/- 37% increase, n = 6) after inhibition of nitric oxide synthase with L-NG-monomethylarginine (LNMMA, 500 microM), an effect abrogated by L-arginine (1 mM). TNF alpha (0.0042, 0.042, and 0.42 micrograms/ml) selectively inhibited contractions of the BPA to SNS without affecting the contraction of the BPA to exogenous norepinephrine. In BPA incubated with LNMMA (5-500 microM), TNF alpha facilitated rather than inhibited SNS. TNF alpha increased the formation of amperiometrically measured free nitric oxide in bovine adrenal chromaffin cells in primary culture. The data show that in the absence of LNMMA, TNF alpha releases free nitric oxide from a sympathetic neuron and selectively inhibits the contractions of the BPA to SNS. In BPA in which nitric oxide synthase I is inhibited by LNMMA, TNF alpha amplifies the contractions to SNS, even in the absence of endothelium. Thus, TNF alpha can modify vascular smooth muscle tone by affecting SNS. TNF alpha inhibits SNS at the level of the neuron by a mechanism involving the L-arginine-nitric oxide pathway. TNF alpha-induced suppression of SNS and neurotransmission may contribute to the hypotension and peripheral neuropathy of sepsis. |
| 1993 | Interleukin-1 (IL-1) receptor antagonist prevents Staphylococcus epidermidis-induced hypotension and reduces circulating levels of tumor necrosis factor and IL-1 beta in rabbits. | Infect Immun | Similar to shock in gram-negative sepsis, shock from gram-positive organisms is mediated, in part, by tumor necrosis factor (TNF) and interleukin-1 (IL-1). In the present study, rabbits were infused with IL-1 receptor antagonist (IL-1ra) prior to and during Staphylococcus epidermidis-induced hypotension. After injection of bacteria, a maximal fall in mean arterial pressure to -42% below baseline occurred at 200 min in vehicle-treated animals compared with a nonsignificant decrease of only 7% in the IL-1ra-treated group (P < 0.01, vehicle versus IL-1ra). A similar attenuation was observed in the fall in systemic vascular resistance (P < 0.05). After the injection of S. epidermidis, TNF levels rose to a peak elevation of 475 +/- 160 U/ml in vehicle-treated rabbits, but in rabbits receiving IL-1ra, maximal TNF levels rose only to 85 +/- 23 U/ml (P < 0.01). Plasma IL-1 beta reached maximal concentrations at 180 min of 364 +/- 71 pg/ml in vehicle-treated animals but only 145 +/- 12 pg/ml in rabbits given IL-1ra (P < 0.05). The reductions in TNF and IL-1 were not due to interference by IL-1ra in the respective assays. In vitro, IL-1ra inhibited S. epidermidis-induced TNF from mononuclear cells by 31% +/- 11%, from spleen cells by 17% +/- 4% (P < 0.05), and from whole blood by 42% +/- 17%. Despite the near reversal of the fall in mean arterial pressure and systemic vascular resistance in IL-1ra-treated rabbits, leukopenia and thrombocytopenia were unaffected. These results demonstrate that IL-1ra blocks shock-like hemodynamic parameters and reduces circulating IL-1 and TNF levels in a model of gram-positive sepsis. |
| 1993 | NG-monomethyl-L-arginine does not restore loss of hypoxic pulmonary vasoconstriction induced by TNF-alpha. | J Appl Physiol (1985) | Tumor necrosis factor-alpha (TNF-alpha) causes systemic hypotension, pulmonary vasodilation, and loss of hypoxic pulmonary vasoconstriction. NG-monomethyl-L-arginine (L-NMMA) inhibits nitric oxide (NO) production and prevents some systemic manifestations of TNF-alpha. We tested using an isolated perfused canine lobe whether NO also mediates the pulmonary vascular effects of TNF-alpha. Total resistance (RT) was measured during control and hypoxic ventilation over a 90-min period in six control lobes, five lobes treated with TNF-alpha (250 micrograms), six lobes treated with L-NMMA (200 mg), and five lobes treated with L-NMMA (200 mg) + TNF-alpha (250 micrograms). In the control lobes RT increased (P < 0.02) from 0.0474 +/- 0.0105 to 0.0677 +/- 0.0133 cmH2O.ml-1 x min during normoxic and hypoxic ventilation, respectively. RT decreased (P < 0.05) from a baseline of 0.0593 +/- 0.0133 to 0.0449 +/- 0.0176 cmH2O.ml-1 x min 30 min after TNF-alpha administration and did not further change during hypoxic ventilation (0.0475 +/- 0.0107 cmH2O.ml-1 x min). L-NMMA pretreatment did not prevent the TNF-alpha-induced loss of hypoxic pulmonary vasoconstriction, with values of RT unchanged from normoxic (0.0541 +/- 0.0067 cmH2O.ml-1 x min) to hypoxic (0.0545 +/- 0.0078 cmH2O.ml-1.min) ventilation (P > 0.10) in the L-NMMA + TNF-alpha group after TNF-alpha administration. We conclude that NO is not the mediator responsible for the acute pulmonary vascular effects of TNF-alpha. |
| 1993 | [Protective effect of monoclonal antibody of tumor necrosis factor-alpha for vital organs in a model suffering from intestinal ischemia and reperfusion injury]. | Zhonghua Wai Ke Za Zhi | Monoclonal antibody to tumor necrosis factor-alpha (TNFa-MAb), z8, was used to explore protective effect on multiple organ dysfunction caused by intestinal ischemia and reperfusion in rats. Systemic plasma TNF level rose rapidly after release of the clamp, on superior mesenteric artery, and reached peak level 2 hours later. Endotoxemia and bacteremia were associated with systemic TNF level, and portal endotoxin concentration increased significantly before elevation of TNF activity. Pretreatment with anti-TNFa antibody markedly attenuated the increase of TNF level and provided protection from the development of hypotension, vital organ dysfunction, and metabolic acidosis. As a result the survival rate in treatment group increased by 35.7%. Our results demonstrated that TNF might play an important role in mediating the pathophysiologic changes in the pathogenesis of multiple organ damage in this intestinal ischemia-reperfusion injury model, and monoclonal antibody to TNF offered significant protection against multiple organ dysfunction or failure after severe trauma. |
| 1993 | Interferon-alpha and interleukin-2 in the treatment of metastatic melanoma. Comparison of two phase II trials. | Cancer | Interferon-alpha (IFN alpha) and interleukin-2 (IL-2) are active agents against malignant melanoma. There is, however, no consensus on the optimal dosing schedule of both drugs. This is a report of two sequential immunotherapy trials in patients with metastatic melanoma using two different IL-2 dosing schedules.Schedule A consists of IFN alpha, 10 million U/m2/day subcutaneously for 5 days, followed by continuous intravenous infusion of IL-2, 1 mg/m2/24 hours for 5 days. Schedule B consists of the same dose of IFN alpha, but a modified regimen of IL-2. To improve the induction of high-affinity IL-2 receptors, the initial IL-2 dose was increased (1 mg/m2/6 hours, followed by 1 mg/m2/12 hours, and 1 mg/m2/24 hours). To reduce toxicity, the dose was reduced thereafter to 0.25 mg/m2/24 hours for the following 3 days. Both regimens were repeated after 4 weeks.27 patients were treated with schedule A with a response rate of 18% (1 complete response [CR], 4 partial responses [PR]), 95% confidence interval, 6-36%. The response rate in 27 patients treated with schedule B was 41% (3 CR, 8 PR), 95% confidence interval, 22-61%. Severe, often dose-limiting toxicity was associated with IL-2 in schedule A, particularly hypotension and fluid retention. Toxicity was reduced significantly in schedule B. Maximal serum levels of soluble CD25 were 17,022 +/- 13,070 U/ml in schedule A, and 31,148 +/- 4227 U/ml in schedule B (P < or = 0.01). Serum levels of TNF alpha were significantly lower in schedule B than in schedule A, as were the side effects.Toxicity of IL-2 is reduced by modifying the schedule of administration, which also enhances the immunologic response and appears to increase the response rate. |
| 1993 | Tumor necrosis factor-induced mortality is reversed with cyclooxygenase inhibition. | Ann Surg | The authors hypothesized that TNF would induce eicosanoid synthesis, and a cyclooxygenase inhibitor would attenuate both eicosanoid synthesis and improve survival in an LD90 TNF-induced (150 ng/kg/i.v./5 min) mortality model.Tumor necrosis factor is a cardinal mediator in sepsis; however, little is known about its effects on arachidonate metabolism.Conscious male rats with carotid arterial and jugular venous catheters were randomized for mortality: group I, TNF alone (150 kg/i.v./15 min, n = 30); group II, ibuprofen (30 mg/kg/i.v. at t = -20 and +240 min), plus TNF, (n = 28); and for hemodynamics, eicosanoid synthesis, blood gases: group III, TNF alone, (n = 8); group IV, ibuprofen + TNF (n = 8); group V, monoclonal antibody to TNF plus TNF (n = 8). Mortality was determined at 4-72 hr. Other parameters determined over 4 hours (0, 5, 60, 120, 240 min).TNF stimulated synthesis of (a) TXB2 (71 +/- 30 pg/ml, mean +/- SE at base vs. 117 +/- 18 at 4 hr, p < 0.02); (b) PGE2 (70 +/- 6 pg/ml at base vs. 231 +/- 68 at 4 hr, p < 0.02); (c) 6PGF (52 +/- 6 pg/ml at base vs. 250 +/- 80 at 4 hr, p < 0.02). Ibuprofen significantly (p < 0.05) inhibited eicosanoid synthesis from TNF. TNF-induced mortality (87%, 26/30) was dramatically decreased with ibuprofen (11%, 3/28), at 4, 24, and 72 hr (p < 0.01). Monoclonal antibody to TNF prevented all abnormalities and had 100% survival. Hemodynamic events were similar in both groups, but metabolic acidosis was attenuated with ibuprofen.TNF stimulates arachidonic acid metabolism in vivo. A cyclooxygenase inhibitor attenuates eicosanoid synthesis and dramatically improves survival. TNF appears to have different effect on tissues that synthesize certain eicosanoids. Hypotension from TNF is not mediated via the eicosanoids. TNF-induced mortality, like endotoxemia/sepsis may be mediated, in part, via arachidonic acid metabolites. These new findings support the notion that cyclooxygenase inhibitors may be used as adjunctive therapy in clinical sepsis. |
| 1993 | TNF-alpha and cyclooxygenase metabolites do not modulate C. albicans septic shock with disseminated candidiasis. | J Appl Physiol (1985) | We analyzed differences in host regulation of tumor necrosis factor-alpha (TNF-alpha) production and pathophysiological responses in conscious rats after infection with two strains of pathogenic Candida albicans spp. (CA-1 and CA-2) compared with Escherichia coli serotype 055:B5 (EC). The hypothesis was tested that, in contrast to EC, hypotension, organ injury, and mortality after candidemia are not obligatorily dependent on TNF-alpha or TNF-alpha-induced cyclooxygenase pathway metabolites. Dose, viability, and strain-specific dependencies were established after intravenous 10(6) or 10(9) viable CA, as well as heat-killed (HK) or Formalin-inactivated (FI) CA blastospores, compared with live EC at the 24-h LD25 [10(9) colony-forming units (CFU)] and LD100 (10(10) CFU). Shock without endotoxemia developed 4-8 h after 10(9) live CA-1 or CA-2 (LD100 at 24 h) with disseminated yeast-mycelial transformation and increased microvascular permeability in multiple organs but not after HK or FI CA-1. Peak serum TNF-alpha after an LD100 of CA-1 or CA-2 was < 3% of LD25 EC values and was < 1% of peak values during lethal bacteremia. Similar pathogen-specific differences were found in liver- and lung-associated TNF. Production of functionally inactive TNF-alpha during candidemia was excluded by enzyme-linked immunosorbent assay and sodium dodecyl sulfate-polyacrylamide gel electrophoresis with Western blotting. Passive immunization against TNF-alpha 2 h before microbial challenge was not protective against CA but prevented otherwise lethal EC sepsis. Cyclooxygenase inhibition also failed to attenuate candidemic shock. We conclude that the magnitude and kinetics of TNF-alpha production and TNF-alpha-dependent immunophysiological responses are differentially regulated after lethal fungal vs. gram-negative bacterial infection. Thus TNF-alpha is not a pivotal mediator of the acute Candida septic shock syndrome with disseminated candidiasis. |
| 1993 | A reconstituted, apolipoprotein A-I containing lipoprotein reduces tumor necrosis factor release and attenuates shock in endotoxemic rabbits. | Circ Shock | A reconstituted lipoprotein, containing human apolipoprotein A-I and phosphatidylcholine (1:200, molar ratio), referred to as ApoLipo, was used prophylactically in an endotoxin shock model in anesthetized rabbits. ApoLipo was administered at a dose of 75 mg protein/kg body weight 15 min before the beginning of a slow, continuous lipopolysaccharide (LPS, endotoxin) infusion (4.17 micrograms LPS/kg/hr). During the 6 hr LPS infusion, the Control-LPS group manifested a marked increase in serum tumor necrosis factor (TNF, peak value 7.82 [2.7-11.2] ng/ml at 1 hr), and many of the pathophysiologic sequelae of endotoxin shock, including hypotension (MAP: 59 +/- 7 mmHg) and metabolic acidosis (BE: -9.9 +/- 2.7) at 3 hr, and a severe neutropenia developed rapidly (PMN count: 5 +/- 3% of baseline at 30 min). In the ApoLipo treated group, serum TNF levels did not rise during the course of LPS infusion (0.1 [0.06-0.64] ng/ml at 1 hr). Hypotension (77 +/- 2 mmHg) and acidosis (-2.7 +/- 0.4) were also significantly attenuated, and the appearance of leukopenia was delayed by 1 hr (110 +/- 12% at 30 min, but 9 +/- 2% at 2 hr). Endotoxemia in the ApoLipo treated group was reduced in comparison to controls, albeit nonsignificantly. The infusion of the same dose of phosphatidylcholine without apoA-I was significantly less efficacious. |
| 1993 | Characterization of endogenous cytokine concentrations after high-dose chemotherapy with autologous bone marrow support. | Blood | Endogenous cytokines are thought to mediate numerous biologic processes and may account for some adverse effects experienced following the administration of recombinant proteins. This study describes the pattern of endogenous cytokine exposure following high-dose chemotherapy. Blood concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), macrophage colony-stimulating factor (M-CSF), and erythropoietin (EPO) were measured by enzyme-linked immunosorbent assay (ELISA) methods in 68 patients receiving the same ablative chemotherapy regimen (cyclophosphamide, cisplatin, carmustine). Patients were grouped according to cellular support (autologous bone marrow [BM] CSF-primed peripheral blood progenitor cells [PBPCs]) and prescribed growth factor (recombinant human granulocyte or granulocyte-macrophage colony-stimulating factor [rHuG-CSF or rHuGM-CSF]). Leukocyte reconstitution was most accelerated in the groups treated with PBPCs and rHuG-CSF. IL-6, M-CSF, and TNF-alpha concentrations were higher in the groups treated with rHuGM-CSF and without PBPCs. Maximal endogenous cytokine concentrations occurred approximately 12 days after BM reinfusion. High concentrations of EPO occurred in patients experiencing significant hypotension despite routine transfusions for hematocrit < 42%. High M-CSF and IL-6 levels were associated with increased platelet transfusion requirements. Concentrations of all four cytokines were significantly higher in patients experiencing renal or hepatic toxicity, with elevations occurring in a predictable sequence and M-CSF elevations occurring first. This report shows that endogenous cytokine concentrations may be influenced by either cellular or CSF support and are associated with differences in platelet reconstitution and organ toxicity. |
| 1993 | Effects of pentoxifylline on tumor necrosis factor production and survival during lethal E. coli sepsis vs. disseminated candidiasis with fungal septic shock. | Circ Shock | Lethal circulatory shock during microbial sepsis is thought to be initiated by early molecular events, including production of tumor necrosis factor (TNF) and cytokine-mediated upregulation of neutrophil (PMN) function, irrespective of the causative organism. The phosphodiesterase inhibitor pentoxifylline (PTX) inhibits TNF gene transcription and modulates PMN function, and has been shown to improve outcome in experimental sepsis. We hypothesized that PTX would attenuate gram-negative and fungal septic shock by different mechanisms: reduced TNF production in Escherichia coli (EC) sepsis vs. enhanced PMN-mediated defense during Candida albicans (CA) fungemia. Conscious chronically catheterized rats received PTX (25 mg/kg, i.v.) before i.v. challenge with 10(10) viable EC (serotype 055:B5), 10(9) viable serotype A yeast-phase CA (each the LD100 in < 24 hr in naive rats), or normal sterile saline (NSS), and then PTX posttreatment (6.5 mg/hr x 4.5 hr). Treatment controls received NSS before and after challenge. Serum TNF peaked 1.5 hr after EC infection in NSS-treated animals (1654 +/- 390 U/ml, mean +/- SE), and was significantly reduced by PTX (120 +/- 32 U/ml, P < 0.01), but PTX did not improve 24 hr survival. PTX also aggravated systemic hypotension after EC, and did not modify neutropenia, thrombocytopenia, or microvascular permeability assessed by organ wet/dry weight (W/D) ratios. Peak serum TNF in CA + NSS animals (130 +/- 45 U/ml) was delayed 8 hr compared to EC animals, and were not reduced by PTX (67 +/- 25 U/ml, P = NS). Moreover, PTX did not alter CA-induced mortality, hypothermia, hypotension, neutropenia, increased lung W/D, or interstitial and alveolar hemorrhage. We conclude that PTX-induced suppression of endogenous TNF production does not prevent gram-negative shock in this model, possibly due to impaired TNF-mediated antibacterial host defense. Since fungal septic shock with acute disseminated candidiasis evolves prior to significant increases in circulating TNF, PTX also appears ineffective in its treatment. |
| 1993 | Chemically induced hypotension increases PGE2 release and depresses macrophage antigen presentation. | Am J Physiol | Hemorrhagic shock causes severe depression of macrophage functions and is associated with increased susceptibility to sepsis. Because hemorrhagic shock and resuscitation encompasses several pathophysiological conditions, such as hypotension, low-flow conditions, hypoxia, and reperfusion injury, it remains unknown whether severe hypotension in the absence of blood loss has any adverse effects on macrophage functions. To study this, systemic arterial hypotension was induced in C3H/HeN mice for 15 min by intravenous infusion of sodium nitroprusside or ATP-MgCl2. Peritoneal macrophages (PM) was harvested 20 h later with lavage. Antigen presentation was measured by coculturing PM with the D10.G4.1 Th cell clone. Tumor necrosis factor (TNF), interleukin (IL)-6, IL-1, and prostaglandin (PG) E2 levels in supernatants of PM stimulated with lipopolysaccharide were measured with bioassays or radioimmunoassay. Systemic arterial hypotension resulted in a significant decrease of PM capacity to present antigen. Although the release of TNF, IL-6, and IL-1 by PM was unaltered after hypotension, PGE2 release by PM was significantly elevated compared with the control group. These data indicate that chemically induced systemic arterial hypotension without blood loss leads to a depression of antigen presentation, which may be caused by elevated release of the immunosuppressive eicosanoid PGE2. |
| 1993 | CGS 8515 and indomethacin attenuate cytokine-induced cardiopulmonary dysfunction in pigs. | Am J Physiol | We evaluated the effect of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 alpha (IL-1 alpha) on pig cardiopulmonary function by intravenously infusing each cytokine individually or in combination (0.5 microgram/kg from 0 to 0.5 h + 5 ng.kg-1 x min-1 from 0.5 to 6 h for each cytokine). The role of eicosanoids in mediating the TNF-alpha + IL-1 alpha-induced cardiopulmonary dysfunction was also investigated by pretreating cytokine-infused pigs with CGS 8515 (5-lipoxygenase inhibitor) or indomethacin (cyclooxygenase inhibitor). Coinfusion of TNF-alpha with IL-1 alpha caused additive increases (P < 0.05) in total peripheral resistance and plasma concentrations of 6-keto-prostaglandin F1 alpha (PGF1 alpha). The increases in mean pulmonary arterial pressure (Ppa), pulmonary vascular resistance (PVR), alveolar-arterial O2 gradient (AaDO2), alveolar dead space-to-tidal volume ratio (VD/VT), and plasma concentrations of thromboxane B2 were either additive or synergistic. CGS 8515 blocked the TNF-alpha + IL-1 alpha-induced increases (P < 0.05) in mean aortic pressure, total peripheral resistance (4-6 h), VD/VT (5-6 h), and, at 6 h, attenuated the increases in Ppa, PVR, and AaDO2. Indomethacin blocked or attenuated the cytokine-induced increases (P < 0.05) in Ppa, PVR, AaDO2, VD/VT, and plasma concentrations of thromboxane B2 and 6-keto-PGF1 alpha. The 1-to 2-h systemic hypotension, caused by TNF-alpha + IL-1 alpha, was not abrogated by either indomethacin or CGS 8515. The cytokines did not alter plasma concentrations of leukotriene B4 or 5-hydroxyeicosatetraenoic acid. We conclude that coinfusion of TNF-alpha with IL-1 alpha induces physiological responses that are additive or synergistic and that cyclooxygenase and 5-lipoxygenase products (other than leukotriene B4 and 5-hydroxyeicosatetraenoic acid) importantly mediate cardiopulmonary dysfunction in pigs infused with TNF-alpha + IL-1 alpha. |
| 1993 | Anti-lipopolysaccharide monoclonal antibodies inhibit macrophage TNF messenger RNA synthesis in vitro. | J Surg Res | Gram-negative bacterial lipopolysaccharide (LPS, endotoxin) directly stimulates macrophages to produce tumor necrosis factor (TNF). TNF, in turn, produces a constellation of adverse effects that includes hypotension, systemic acidosis, arterial hypoxemia, and death. Transcription of the TNF gene occurs within minutes of LPS stimulation and appears to be a critical control point in the synthesis and secretion of TNF protein by macrophages. We hypothesized that murine monoclonal antibody (mAb) 8G9 directed against Escherichia coli 0111:B4 LPS would provide protective capacity against an E. coli 0111:B4 bacterial challenge in vivo and would concurrently inhibit LPS-induced synthesis of TNF mRNA and secretion of TNF protein in vitro. E. coli 0111:B4 LPS was used to stimulate a macrophage-derived cell line (RAW 264.7) to produce TNF in the presence or absence of mAb 8G9. Media alone and LPS without 8G9 mAb served as controls against which the effect of 8G9 mAb was compared. Total cellular RNA was purified and analyzed by a Northern blotting technique utilizing a radiolabeled cDNA probe specific for TNF mRNA. TNF mRNA levels from each sample were quantitated by autoradiograph densitometry. Pretreatment with mAb 8G9 provided protective capacity against an intraperitoneal E. coli 0111:B4 bacterial challenge in vivo when compared with saline pretreatment alone (22% versus 90% mortality respectively, P < 0.05). Preincubation of LPS with mAb 8G9 resulted in a significant inhibition of LPS-induced TNF mRNA synthesis (63 +/- 20%, P < 0.01) and TNF protein secretion (88 +/- 10%, P < 0.001) in vitro.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1993 | Serum cytokine levels in human septic shock. Relation to multiple-system organ failure and mortality. | Chest | Cytokines have been associated with the development of sepsis and diffuse tissue injury following septic or endotoxic challenges in humans. Furthermore, relative organ-system dysfunction, not specific organ dysfunction, appears to predict outcome from critical illness. We hypothesized that persistence of inflammatory cytokines within the circulation, reflecting a generalized systemic inflammatory response, is associated with multiple-system organ failure (MSOF) and death from critical illness. In addition, since hepatic function is central to host-defense homeostasis, we further reasoned that critically ill patients with hepatic cirrhosis would have an increased incidence of MSOF and death following sepsis associated with a persistence of cytokines in the blood.We measured serum levels of tumor necrosis factor (TNF), interleukin (IL) 1, IL-2, IL-6, and interferon gamma (IFG) serially for the first 48 h following the onset of hypotension (systolic blood pressure < 90 mm Hg) thought likely to be due to sepsis in all patients presenting to one ICU. These data were correlated with initial severity of shock and retrospective determination of septic or nonseptic origin, preexistent hepatic cirrhosis, subsequent development of MSOF, and outcome.Fifty-three specific episodes of shock in 52 patients were recorded (35 septic and 18 nonseptic episodes). Mortality was higher in septic patients (41 vs 17 percent, p < 0.01), as was the development of MSOF (29 vs 6 percent, p < 0.001), incidence of cirrhosis (21 vs 0 percent, p < 0.01), and TNF levels over the study interval (p < 0.01). Nonseptic patients also had an initial elevation in TNF over 48-h levels (p < 0.05) that were higher than serum levels reported for normal subjects (chi 2, p < 0.05). There was no relation between peak TNF level and outcome. Sixty-seven percent of the cirrhotic patients had development of MSOF and died, while only 30 percent of the noncirrhotic patients had development of MSOF or died (p < 0.05). The TNF and IL-6 levels in patients who had MSOF or who died were both elevated and did not decrease over time independent of presence or absence of sepsis (p < 0.01). Similarly, IL-6 levels after 12 h were higher in cirrhotic patients than in noncirrhotic septic patients (p < 0.05). No elevation in IL-1, IL-2, or IFG was seen in any patient subpopulation.TNF and IL-6 serum levels are higher in septic than in nonseptic shock, but the persistence of TNF and IL-6 in the serum rather than peak levels of cytokines predicts a poor outcome in patients with shock. |
| 1992 | Evidence that antihuman tumor necrosis factor monoclonal antibody prevents OKT3-induced acute syndrome. | Transplantation | We have used an antihuman tumor necrosis factor monoclonal antibody, CB006 (murine IgG1), to prevent the OKT3-induced acute clinical syndrome. This syndrome is due to the massive, although transient release in the circulation of various cytokines (TNF, interferon gamma, interleukin 2, interleukin 6) and represents one important side effect linked to in vivo use of OKT3. Fourteen kidney allograft recipients undergoing prophylactic OKT3 therapy were treated with CB006 in a single i.v. injection of either 0.4 mg/kg (group I, 7 patients) or 2 mg/kg (group II, 7 patients), 1 hr before the first OKT3 administration. Nineteen consecutive patients formed a historical control group. None of the CB006-pretreated patients showed any of the common, severe OKT3-associated symptoms (hypotension, respiratory distress, or neurotoxicity), which were observed in 10% of the historical controls. In addition, CB006-treated patients showed a lower frequency of pyrexia (> or = 39 degrees C) and gastrointestinal symptoms. None of the CB006-treated patients presented severe vomiting or diarrhea, defined as repeated episodes inducing significant fluid and electrolyte loss. Two out of the 7 patients in group I and group II had mild transitory diarrhea. Mild single vomiting episodes occurred in 2 group I patients and 3 group II patients. At variance in all controls, gastrointestinal symptoms were long lasting and associated with major prostration due to electrolyte and fluid loss. Importantly, CB006-treated patients who presented mild symptoms had detectable bioactive circulating TNF, showing incomplete inactivation of OKT3-induced TNF by CB006. CB006 was perfectly well tolerated, did not induce xenosensitization, and did not affect the biological or clinical effectiveness of OKT3. |
| 1992 | Phase I evaluation of thrice-daily intravenous bolus interleukin-4 in patients with refractory malignancy. | J Clin Oncol | A phase I dose-escalation trial of recombinant human interleukin-4 (IL-4) was performed to determine its toxicity, biologic activity, and potential antineoplastic effects.Ten patients with refractory malignancies received IL-4 by bolus intravenous injection every 8 hours on days 1 to 5 and 15 to 19 (maximum, 28 doses) of a 31-day study period. Three patients received 10 micrograms/kg per dose and seven received 15 micrograms/kg per dose of IL-4.Toxic symptoms noted at the second dose level included nasal congestion, diarrhea, nausea and vomiting, fatigue, anorexia, headache, dyspnea, and capillary leak syndrome (median weight gain, 6.1%; range, 3.4% to 11.7%). Fever or sustained hypotension sufficient to require pressors did not occur. Decreases in lymphocyte count and serum bicarbonate, sodium, albumin, fibrinogen and immunoglobulin (Ig) levels, and increases in hematocrit, prothrombin time/partial thromboplastin time (PT/PTT), soluble CD23, and, occasionally, serum creatinine and transaminases occurred. All side effects resolved by day 31. Phenotypic analysis of peripheral-blood mononuclear cells (PBMC) showed a decrease in the percentage of circulating CD16 and CD14(+) cells. Plasma tumor necrosis factor (TNF) and IL-1 beta levels were unaffected, whereas serum C-reactive protein (CRP) concentrations increased slightly and plasma IL-1 receptor antagonist (IL-1RA) levels increased markedly. No tumor responses were observed.We conclude that 10 micrograms/kg per dose of IL-4 is the maximum-tolerated dose for this schedule, although 15 micrograms/kg per dose can be tolerated if more intensive, but still non-intensive care unit level care is provided. The results of this study should aid in the design of future phase II trials that involve IL-4 alone or phase I studies that combine IL-4 with other cytokines such as IL-2. |
| 1992 | Interleukin-1 and tumor necrosis factor and their naturally occurring antagonists during hemodialysis. | Kidney Int Suppl | Cytokines are polypeptides which possess various biological properties affecting host defense function and response to disease. Two cytokines, interleukin-1 (IL-1) and tumor necrosis factor (TNF) induce fever, hypotension and inflammation when injected into animals or human subjects. In humans injected with either IL-1 or TNF, sleepiness, generalized myalgias and headache are commonly reported. Therefore, the production of IL-1 and TNF as a consequence of hemodialysis was hypothesized to explain, in part, the signs and symptoms of the dialysis patient. Laboratory studies confirmed that the activation of complement and the passage of microbial products from the dialysate into the blood compartment induces the synthesis of IL-1 and TNF. Although elevated production of IL-1 and TNF in the mononuclear cells and in the circulation of patients during and after hemodialysis have been reported, these levels have not been a consistent finding and are low compared to the amount of dialysis related symptoms. Recent studies, however, demonstrate that IL-1 and TNF have naturally occurring antagonists which specifically block the biological activities of these two cytokines. The IL-1 receptor antagonist blocks IL-1 binding to cells but has no IL-1 activity of itself. Soluble TNF receptors prevent TNF from binding to its cellular receptors and hence serve as anti-TNF mechanisms. These inhibitors are currently in clinical trials for sepsis where efficacy has been demonstrated; however, the IL-1 receptor antagonist (IL-1Ra) and soluble TNF receptors (sTNFR) are likely candidates for use in dialysis patients with symptomatic hypotension. Although levels of IL-1Ra and sTNFR are elevated in patients on HD, these levels reflect the host response to inflammation. It is unclear whether acute or chronic administration of IL-1Ra or sTNFR will be beneficial in treating some of the acute or chronic changes seen in dialysis patients. |
| 1992 | Passive immunization against tumor necrosis factor inhibits interleukin-2-induced microvascular alterations and reduces toxicity. | Surgery | Antineoplastic therapy with interleukin-2 (IL-2) has been limited by dose-dependent systemic toxicities. Previous studies suggest that the hemodynamic instability and "vascular leak syndrome" that develop immediately after IL-2 administration occur secondary to neutrophil-mediated events in the microcirculation. Because IL-2 has limited direct effects on neutrophils and acutely induces the production of tumor necrosis factor-alpha (TNF), we hypothesized that the acute microvascular alterations and hemodynamic instability induced by IL-2 were mediated by TNF.The cremaster muscles of anesthetized rats were prepared for intravital microscopy. All animals were injected with fluorescein isothiocyanate conjugated to bovine serum albumin, and relative interstitial fluorescence was quantitated as an index of macromolecular leakage. Vital signs, leukocyte-endothelial interactions, and interstitial fluorescence were quantitated every 30 minutes for 2 hours after intravenous injections of IL-2, TNF, and IL-2 with polyclonal antibody to TNF.Both IL-2 and TNF acutely induced hypotension, tachycardia, increased macromolecular leakage, and increased leukocyte-endothelial adherence. Polyclonal antibody to TNF effectively inhibited IL-2-induced leukocyte-endothelial adherence, macromolecular leakage, and hypotension.These data suggest that the acute microvascular alterations and hypotension induced by IL-2 are mediated by TNF. |
| 1992 | The cytokine network in the critically ill. | Anaesth Intensive Care | There is increasing experimental and clinical evidence that a number of cytokines play a major role in the response to injury and infection and in the development of organ damage in critically ill patients. Tumour necrosis factor (TNF) is now proposed to be a key mediator of organ injury during sepsis. It is elevated early in the course of septic shock and high levels correlate with unfavourable outcome. In animals it can produce the effects of endotoxin. The prophylactic administration of anti-TNF antisera protects mice and rabbits from lethal effects of lipopolysaccharide. Interleukin-1 (IL-1) is an endogenous pyrogen which induces leukocytosis and muscle catabolism. It causes hypotension and tachycardia by reducing smooth muscle contractility. IL-1 receptor blockers have been shown to diminish mortality in experimental endotoxic shock. Interleukin-6 (IL-6) is a pyrogen and lymphocyte activator. It is the major stimulus to acute phase protein production by the liver. A recently described neutrophil-activating peptide (Interleukin-8; IL-8) may be involved in the pathogenesis of ARDS. High blood levels of IL-8 have been found in patients with septic shock. Platelet-derived growth factor (PDGF) has been shown to stimulate TNF production, leukocyte chemotaxis and pulmonary vasoconstriction in response to endotoxin. Other cytokines and growth factors have not yet been studied in critical illness. The cytokine network can be either protective or damaging. Its activation during critical illness triggers complex and still poorly understood interactions. A better comprehension of its role in protection from infection and in the pathogenesis of multiple organ failure may allow therapeutic manipulations aimed at minimising adverse effects while retaining immunological protection. |
| 1992 | Lipopolysaccharide, tumor necrosis factor, and interleukin-1 interact to cause hypotension. | J Lab Clin Med | Lipopolysaccharide (LPS) causes the syndrome of septic shock by initiating the release of endogenous mediators such as tumor necrosis factor (TNF) and interleukin-1 (IL-1) from macrophages. Hypotension is one of the important clinical features of septic shock; however, TNF is only hypotensive in high doses. Therefore we have investigated the interactions of low, nonhypotensive doses of LPS, IL-1, and TNF in the restrained unanesthetized rabbit. Combinations of nonhypotensive doses of TNF, IL-1, and LPS produced significant (p less than 0.05) decreases in blood pressure as compared with doses of each of the substances alone. TNF bioactivity in animals that were made hypotensive with combinations of TNF, IL-1, and LPS was lower than in animals that were made hypotensive with TNF alone. This suggests that TNF release that is stimulated by LPS is not the sole cause of the hypotension that is seen in this model of endotoxic shock. In this model, interactions of LPS, IL-1, and TNF occur and may explain hypotension during some episodes of sepsis. |
| 1992 | A phase I pharmacokinetic study of recombinant human tumor necrosis factor administered by a 5-day continuous infusion. | Invest New Drugs | Nineteen patients with advanced cancer were entered into a phase I clinical trial of Tumor Necrosis Factor (TNF) which was designed to determine the pharmacokinetic profile, safety, and maximal tolerated dose (MTD) of the recombinant human cytokine in vivo. TNF was administered by continuous infusion for 24 hours followed by pharmacokinetics and a 120-hour infusion repeated every 3 weeks. The initial dose was 40 micrograms/m2 and was ultimately escalated to 200 micrograms/m2. A total of forty 5-day cycles were administered to 18 of these patients; and all were evaluable for toxicity. Toxicities in this trial included fever, chills, rigors, hypotension, headaches, seizures, lethargy, weight loss, and malaise. At all dose levels, but more significantly at the highest doses, hematological toxicities were observed and grade 3 neurotoxicity (headache and confusion), and hypotension were noted. Two patients expired during the study, and this was felt to be related to septic episodes. Because of these severe toxicities, 160 micrograms/m2 was defined as the MTD. At 160 micrograms/m2 peak serum levels occurred within 5-20 minutes of initiation and were not detectable 1 hour later. No anti-tumor responses were observed. No measurable plasma levels of TNF were observed with the administration of doses of 80 micrograms/m2. This dose level could be further studied in phase II studies alone and in combination with other agents, utilizing a continuous infusion schedule. |
| 1992 | Protective effects of a leukotriene inhibitor and a leukotriene antagonist on endotoxin-induced mortality in carrageenan-pretreated mice. | Infect Immun | The leukotrienes and tumor necrosis factor (TNF) play an important role in the pathophysiology of septic shock, in which hypotension, leukopenia, thrombocytopenia, and hemoconcentration are observed. This study was performed to examine the effects of a 5-lipoxygenase inhibitor (AA-861), a selective leukotriene receptor antagonist (ONO-1078), and a cyclooxygenase inhibitor (indomethacin) on endotoxin-induced mortality and TNF production in mice. Mice were injected intraperitoneally with carrageenan (5 mg per mouse), which we previously reported as an effective priming agent for lipopolysaccharide (LPS)-induced TNF production and mortality (M. Ogata, S. Yoshida, M. Kamochi, A. Shigematsu, and Y. Mizuguchi, Infect. Immun. 59:679-683, 1991). The indicated doses of AA-861, ONO-1078, indomethacin, or controls were administrated subcutaneously 30 min before LPS (50 micrograms per mouse) provocation. The mortality of mice was significantly decreased by pretreatment with AA-861 (P less than 0.001) or ONO-1078 (P less than 0.01) but not by pretreatment with indomethacin. The 50% lethal dose of LPS in the mice treated with dimethyl sulfoxide or ethanol was 32 or 33 micrograms, respectively, and it increased to 83 micrograms with AA-861 or 59 micrograms with ONO-1078, respectively. Neither AA-861 nor ONO-1078 suppressed LPS-induced TNF production in sera. Treatment with AA-861 significantly decreased the leukopenia and thrombocytopenia, and ONO-1078 significantly decreased the hemoconcentration and thrombocytopenia. The role of endogenous TNF was also examined in the carrageenan-pretreated mice. Treatment with 2 x 10(5) U of rabbit anti TNF-alpha antibody intravenously 2 h before LPS challenge significantly suppressed the LPS-induced TNF activity and decreased the mortality. Therefore, both leukotrienes and TNF play important roles in endotoxin-induced shock and mortality. |
| 1992 | Tumor necrosis factor and regulation of metabolism in infection: role of systemic versus tissue levels. | Proc Soc Exp Biol Med | Tumor necrosis factor (TNF), a pleiotropic cytokine, is produced by macrophages and other cells in a variety of infectious and noninfectious diseases. Ultimately, the net biological effects of TNF may be either beneficial or injurious to the host. For instance, during overwhelming bacterial infection, the acute overproduction of TNF causes septic shock syndrome characterized by hypotension, organ failure, and death. Antibodies against TNF prevent and reverse these sequelae in animal models of septic shock, and their use in humans is currently under investigation in clinical trials. In another instance, TNF has been implicated as an injurious mediator in the state of malnutrition that complicates the course of chronic infection and cancer. Termed cachexia, this chronic syndrome inevitably causes the afflicted host to succumb from weight loss, anorexia, and catabolism of protein and lipid. Experimental studies of animals exposed to TNF for protracted periods indicate that this cytokine is capable of causing cachexia, and the biochemical basis for these catabolic changes has been identified. More recent data indicate that the detrimental metabolic effects of TNF are not dependent upon its circulating levels in the bloodstream, but rather are dependent upon its actions locally in vital organs (e.g., brain). Thus, the metabolic basis for cachexia in infection may be largely dependent upon the amount of cytokine produced in metabolically important tissues. As a result, circulating TNF levels in cachectic patients may not accurately reflect the metabolic state of the host, and do not correlate to weight loss.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1992 | Endotoxin and hypoxia-induced intestinal necrosis in rats: the role of platelet activating factor. | Pediatr Res | We have previously shown that intravascular platelet activating factor (PAF) causes ischemic bowel necrosis in rats morphologically similar to neonatal necrotizing enterocolitis (NEC). Because endotoxin (LPS) and hypoxia are risk factors for NEC, we studied their effect on PAF metabolism and the development of intestinal injury. Young male Sprague-Dawley rats were anesthetized with pentobarbital and divided into six experimental groups: 1) control, 2) LPS alone (2 mg/kg), 3) hypoxia alone (5% O2), 4) LPS+hypoxia, 5) WEB 2086 (PAF antagonist)+LPS+hypoxia, and 6) SRI 63-441 (PAF antagonist)+LPS+hypoxia. Evaluations included blood pressure recording, superior mesenteric artery blood flow, arterial blood gas, white blood cell count, hematocrit, plasma PAF, plasma acetylhydrolase, plasma tumor necrosis factor, intestinal perfusion, and intestinal injury at 3 h. We found that LPS+hypoxia synergistically contributed to hypotension (mean blood pressure 27 +/- 5.6% baseline versus 101 +/- 3.9% control), metabolic acidosis (pH 7.05, base deficit 24 mEq/L), hemoconcentration, decreased superior mesenteric artery blood flow (2.2 +/- 0.3 mL/min versus 5.8 +/- 0.2 mL/min control), and intestinal injury. The morbidities resulting from LPS+hypoxia were partially or completely prevented by PAF antagonists. In addition, animals treated with LPS+hypoxia had neutropenia, elevated plasma acetylhydrolase, and elevated plasma TNF. These results suggest that endogenous PAF may contribute to LPS+hypoxia-induced intestinal hypoperfusion and necrosis. |
| 1992 | Effect of meningococcal endotoxin in a rabbit model of shock. | Circ Shock | Endotoxin in the form of a lipooligosaccharide (LOS) plays a key role in the development of shock in meningococcal sepsis. To examine hemodynamic and biochemical alterations during meningococcal endotoxic shock, we established a rabbit model. Thirty-nine rabbits, weighing 2.5-4.4 kg, were studied. After anesthesia with intramuscular ketamine (20 mg/kg) and xylazine (4 mg/kg), femoral venous and arterial catheters were inserted. Control animals received only saline, while rabbits in each of four additional groups were given LOS in 10-fold increments from 0.1 microgram/kg to 100 microgram/kg. Mean arterial pressure (MAP), heart rate (HR), respirations (RR), temperature (T), urine output, and arterial blood gases (pH, PCO2, PO2, and bicarbonate) were determined at baseline and hourly. Endotoxin levels and TNF levels were measured at 30, 60, 120, 180, 240, 300, and 360 min post-LOS. Survival was recorded. One-way analysis of variance (ANOVA) and the Scheffe procedure, paired samples t-test, two-tailed t-test, and Fisher's exact test were used. Pearson's coefficients were calculated. Animals receiving meningococcal LOS developed tachycardia and compensated metabolic acidosis with an initially normal pH and MAP. With progression of the shock state, the pH decreased and hypotension ensued. Maximal levels of endotoxin were measured 30 min after LOS injection and declined during the ensuing 6 hr. TNF rose from undetectable to markedly elevated levels and peaked at 60-120 min post-LOS. Increasing the amount of injected endotoxin produced more profound degrees of shock until a dose of 10.0 micrograms/kg was reached. There was no correlation between serum TNF at 60 min and survival at 6 hr or 24 hr.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1992 | Clinical and biologic effects of combination therapy with gamma-interferon and tumor necrosis factor. | Cancer | Tumor necrosis factor (TNF) and gamma-interferon (gamma-IFN) are cytokines with synergistic biologic and antiproliferative effects in vitro and in mouse models. The biologic effects of the combination of TNF and gamma-IFN, however, have not been studied well in humans. A Phase I trial was conducted of TNF and gamma-IFN therapy in 24 patients with advanced malignancies to determine the tolerability of the combination and the biologic effects of TNF and gamma-IFN in vivo. Both TNF and gamma-IFN were administered as 30-minute intravenous infusions three times per week. Doses of TNF ranged from 25 to 100 micrograms/m2; all patients received 100 micrograms/m2 of gamma-IFN. Dose-limiting toxicity consisted primarily of orthostatic hypotension and constitutional symptoms. The maximum tolerated dose level (MTDL) of 50 micrograms/m2 of TNF and 100 micrograms/m2 of IFN-gamma was less than the maximum tolerated dose (MTD) observed in previous Phase I trials of gamma-IFN and TNF alone. Biologic responses were studied in seven patients treated at the MTDL. Serum interleukin-2 receptor levels and neopterin secretion were enhanced significantly 24 hours after therapy (P = 0.002); enhancement of monocyte Fc receptor levels had borderline statistical significance (P = 0.07). With the exception of the mean fluorescent intensity on monocytes positive for histocompatibility antigen HLA-DR (P = 0.03), HLA Class I and II cell surface protein expression was not increased. The combination significantly enhanced indoleamine dioxygenase activity and serum beta 2-microglobulin expression (P less than 0.04) but not 2',5'-oligoadenylate synthetase activity, bactericidal function, or chemiluminescence. These results were compared retrospectively with those observed in previous Phase I trials of gamma-IFN and TNF alone. The combination of TNF and gamma-IFN significantly increased urinary kynurenine levels more than either TNF alone or gamma-IFN alone. Given the limitations inherent in any retrospective analysis, however, the enhancement in the other biologic parameters measured at the MTDL during this trial did not differ significantly from the changes observed at the MTD of either TNF or gamma-IFN alone. It was concluded that the combination of TNF and gamma-IFN, when administered at the MTDL of the combination, does not offer any enhancement in biologic responses over either agent alone. |
| 1992 | Cloricromene, a coumarine derivative, protects against lethal endotoxin shock in rats. | Eur J Pharmacol | Endotoxin shock was induced in male rats by an intravenous (i.v.) injection of Salmonella enteriditis lipopolysaccharide (LPS; 20 mg/kg i.v.). Survival rate, macrophage and serum tumor necrosis factor (TNF-alpha), mean arterial blood pressure (MAP) and white blood cell count were then evaluated. Furthermore the in vitro effect of cloricromene on peritoneal macrophage phagocytosis and TNF-alpha release by primed peritoneal macrophages was investigated. LPS administration caused animal death (0% survival 24 h after endotoxin challenge), hypotension, marked leukopenia and increased the levels of TNF-alpha in both serum and macrophage supernatants. Cloricromene administration (0.5, 1 and 2 mg/kg i.v. 15 min after endotoxin) protected against LPS-induced lethality (100% survival rate 24 h after endotoxin challenge), reverted LPS-induced hypotension and leukopenia, and decreased TNF-alpha in both serum and macrophage supernatants. Finally, cloricromene, added in vitro to peritoneal macrophages collected from endotoxin-treated rats increased macrophage phagocytosis and reduced TNF-alpha formation by activated mononuclear phagocytes. Our data suggest that cloricromene increases survival rate in endotoxin shock through an inhibition of TNF-alpha production. |
| 1992 | Complement activation and the production of inflammatory mediators during the treatment of severe sepsis in humans. | Scand J Infect Dis | Sepsis or septic shock is frequently associated with activation of the complement system, coagulation and fibrinolytic changes and the release of several cytokines. In this study we analyzed the relation of complement activation to the inflammatory mediators, hemodynamic and biochemical parameters and severity of illness and outcome in 20 consecutive patients with clinically defined sepsis. Levels of C3a and C3d were elevated in 90% of the patients (median levels 0.19 mg/l and 8.6 mg/l respectively) in comparison to 14% and 42%, respectively of 7 patients with non-septic shock. Levels of C4 were decreased in only 1 of the 20 septic patients. Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, respectively (median levels 122 ng/l and 1300 U/ml) and were clearly interrelated (r = 0.67, p less than 0.01). C3a levels correlated with the APACHE II score (r = 0.57, p less than 0.05) and high C3a levels were associated with fatal outcome (p less than 0.05). C3a was also correlated inversely with mean arterial pressure (r = 0.50, p less than 0.01). Levels of complement C3a and C3d significantly correlated with levels of plasminogen activator inhibitor-1 (PAI) and correlated inversely with AT-III levels. We found no correlation between these complement products and leukocyte counts or lactate levels, nor was there a correlation between C3a or C3d and the cytokines TNF and IL-6. Levels of C3a and C3d did not decrease significantly during the first 24 h of treatment, in contrast to a clear decrease in IL-6 levels in all patients and a decrease in TNF in the surviving patients. TNF levels remained stable or increased in the non-survivors. We conclude that both the complement system and the cytokine system are involved in the pathogenesis of septic shock and may be involved in the development of some of the fatal complications like hypotension and disseminated intravascular coagulation. |
| 1992 | Recombinant human TNF-alpha: preclinical studies and results from early clinical trials. | Immunol Ser | The application of recombinant DNA technology to the production of tumor necrosis factor has resulted in the availability of large quantities of a highly purified protein product. This product has been evaluated extensively in preclinical studies, which have documented a direct cytostatic and cytotoxic effect on human tumor cells, as well as a variety of immunomodulatory effects on various immune effector cells, including neutrophils, macrophages, and T cells. In addition, a number of anti-infective and metabolic effects have been documented. In addition to its in vitro effects, rTNF has been shown to have antitumor activity in vivo in preclinical studies involving both transplantable murine tumors and human tumor xenografts. Such observations have led to the evaluation of rTNF as a potential antineoplastic agent in humans. Both single- and multiple-dose phase I studies have confirmed that rTNF can be safely administered to patients with advanced malignancies in a dose range associated with anticancer effect without concomitant serious toxicities such as shock and cachexia. The most commonly observed clinical toxicities include constitutional symptoms, such as fever, chills, headache, and fatigue, and toxicities, which can be at least partially controlled with concomitant administration of nonsteroidal anti-inflammatory drugs, such as acetaminophen and meperidine. Hypotension, which occurs at high doses administered by short intravenous infusion, can usually be prevented by prehydration with intravenous fluids or otherwise controlled by the administration. An intense local inflammatory reaction at the injection site as well as thrombocytopenia appear to be the dose-limiting toxicities after subcutaneous and intramuscular administration. Neurologic toxicity is infrequent, except following continuous intravenous infusion, where it may manifest as transient focal neurologic deficits or seizure. Prolonged administration of rTNF at higher doses may be associated with transient, subclinical decreases in diffusing capacity. Patients with underlying cardiopulmonary disease should be excluded from rTNF therapy in future clinical studies until the end-organ toxicities of this agent are better defined. For at least one preparation of rTNF there appears to be no evidence for the formation of antibodies to rTNF in patients who receive multiple administrations of the agent. Pharmacokinetic studies have shown a relatively rapid clearance following intravenous infusion with a half-life of 15 to 30 min and dose-dependent pharmacokinetics. rTNF can be detected in the serum following intramuscular or subcutaneous injection at only relatively high doses, suggesting a decreased bioavailability with the routes of administration. Early phase I studies defined tolerable dose ranges for each route of administration and began to explore immunomodulatory and metabolic effects of rTNF.(ABSTRACT TRUNCATED AT 400 WORDS) |
| 1992 | Differential effects of hemorrhage on Kupffer cells: decreased antigen presentation despite increased inflammatory cytokine (IL-1, IL-6 and TNF) release. | Cytokine | Although studies indicate that simple hemorrhage induces profound depression of cell-mediated immunity and enhances the host's susceptibility to sepsis, the mechanism for this remains unknown. Since the Kupffer cells (KC) are positioned to have constant exposure to various immunomodulators and antigens released during hypotension, we have examined whether antigen presentation by KC, a critical component in eliciting an antigen specific immune response or those processes associated with it, are depressed following hemorrhage. C3H/HeN mice were bled to and maintained at a mean BP of 35 mmHg for 60 min, and then resuscitated with their own blood and adequate fluids. The mice were killed at varying periods of time after hemorrhage to obtain KC from the liver, and assessed for their capacity to present antigen to a sensitized clone Th/cell line (D10.G4.1). Hemorrhaged mice exhibited a marked decrease in antigen presenting capacity beginning as little as 2 h and lasting up to 3-5 days post-hemorrhage. The ability of KC to express mouse interleukin 1 (mIL-1) showed a significant decline at 2 h following hemorrhage, but this effect was not apparent at 24 h post-hemorrhage. In contrast, KC capacity to produce IL-1, IL-6 and tumour necrosis factor (TNF) (cytokines which can co-stimulate T cell antigen presentation) was markedly enhanced during the first 24 h following hemorrhage. A marked decrease was observed in both the mean of the average fluorescence per KC and the percent of Ia antigen-positive KC which persisted for at least 3 days after hemorrhage. The ability of ibuprofen (a cyclooxygenase blocker) to partially restore the antigen presenting capacity of KC from hemorrhaged mice in vitro indicates that prostaglandins are involved in this dysfunction. Thus, the depression of KC antigen presentation, as well as the enhanced capacity of these cells to release inflammatory mediators (TNF, IL-1, IL-6 and prostanoids) which may produce cell and organ dysfunction, could contribute to the host's enhanced susceptibility to sepsis following hemorrhage. |
| 1992 | Combination of interleukin-2 and interferon-alpha in renal cell carcinoma and malignant melanoma: a phase II clinical trial. | Biotechnol Ther | A total of 22 patients with metastatic renal cell carcinoma or malignant melanoma were treated in a phase II study to assess the safety and efficacy of combination therapy of interleukin-2 (IL-2) and interferon-alpha (IFN-alpha). 3 x 10(6) U/m2/day recombinant human (rh)IL-2 was given in repetitive cycles by continuous 24-h infusion from day 1 to day 4; 6 x 10(6) U/m2/day rhIFN-alpha was given subcutaneously on days 1 and 4. There was one complete remission and two partial remissions in the renal cell carcinoma group and two partial remissions in the malignant melanoma group, giving an overall response rate of 24% in 21 evaluable patients with a median response duration of 5+ months. Toxicity was moderate, with hypotension, fever, chills, nausea, neurotoxicity, and dermatitis as prominent side effects. Measurement of circulating cytokine levels showed increased serum tumor necrosis factor-alpha (TNF), interferon-tau, and soluble interleukin-2 receptor levels during each cycle with a tendency to higher concentrations of TNF in responders as compared to nonresponders. With regard to therapeutic efficacy and tolerance, our approach might represent an alternative to the high-dose protocols and the labor- and cost-intensive strategies of adoptive immunotherapy. |
| 1991 | [Acute clinical syndrome associated with OKT3 administration. Prevention by single injection of an anti-human TNF monoclonal antibody]. | Presse Med | This study analyzed the capacity of an anti-human tumour necrosis factor (TNF) monoclonal antibody, CB006 (murine IgG1, Celltech), to prevent the OKT3-induced acute clinical syndrome. Fourteen renal allograft recipients undergoing prophylactic OKT3 therapy were included. CB006 was administered as a single i.v. injection, 0.4 mg/kg (Group I, 7 patients) and 2 mg/kg (Group II, 7 patients), one hour prior to the first OKT3 administration. Nineteen consecutive patients that were part of a randomized multicenter trial constituted the historical control group. In all patients CB006 was perfectly well tolerated and significantly decreased the frequency of the common OKT3-associated acute symptoms. None of the CB006 pretreated patients showed severe life threatening symptoms (hypotension, respiratory distress or neurotoxicity), observed in 10 per cent of historical controls. At variance with controls, in CB006 treated patients gastrointestinal symptoms (vomiting, diarrhea) and pyrexia (body temperature greater than or equal to 39 degrees C) appeared in low frequency, were mild and short lasting, never promoting major prostration of the patients due to electrolytes and fluid loss. Importantly, the presence in some patients of these mild symptoms, correlated with detectable bioactive TNF in the circulation thus reflecting incomplete blockade by CB006 of OKT3-induced TNF. CB006 pharmacokinetics data further stressed the need for adequate dosage adaptation. CB006 did not affect the biological or clinical effectiveness of OKT3. None of the patients showed evidence of anti-CB006 xeno-sensitization. |
| 1991 | Single-dose tumor necrosis factor protection against endotoxin-induced shock and tissue injury in rats. | Infect Immun | Tumor necrosis factor (TNF), a macrophage product released in response to endotoxin and other stimuli, has been shown to be a central mediator of endotoxin or septic shock. However, its highly conserved and wide-ranging physiological effects suggest that it may also be an essential cytokine in the host defense against acute bacterial infection or sepsis. A single nontoxic dose of human recombinant TNF administered intravenously 24 h prior to a lethal infusion of Escherichia coli lipopolysaccharide (LPS) completely prevented acute LPS-induced hypotension, ameliorated tissue injury in the lungs and liver, and improved survival in male Fisher 344 rats. The protective effects of TNF were dose dependent and required a 24-h pretreatment interval. After the infusion of LPS, animals in both groups (TNF-treated animals and saline-pretreated controls) initially appeared acutely ill and had a similar severe metabolic acidosis, indicating that TNF did not inactivate or prevent the toxic effects of LPS. Twelve hours after the administration of TNF, the gene for manganous superoxide dismutase, a mitochondrial enzyme which scavenges toxic reactive oxygen species and is induced during conditions which generate a free radical stress, was expressed in liver tissue, suggesting that the induction of manganous superoxide dismutase may be an important in vivo protective mechanism against cellular injury during lethal endotoxemia. |
| 1991 | Fever, hyperdynamic shock, and multiple-system organ failure. A pseudo-sepsis syndrome associated with chronic salicylate intoxication. | Chest | To describe a sepsis-like syndrome associated with chronic salicylate intoxication.Retrospective clinical study.University-affiliated county hospital.Five patients who became accidentally intoxicated while ingesting salicylates on a long-term daily basis.All five salicylate-intoxicated patients had clinical and laboratory features that were highly suggestive of sepsis, but no bacteriologic or pathologic evidence of infection could be documented. Features included fever, leukocytosis with increased band forms, hypotension with a reduced SVR and multiple system organ failure (ARDS, encephalopathy, renal failure, and DIC). A diagnosis of salicylate intoxication was made at the time of admission to the hospital in only one case. In the other four cases, the presumptive diagnosis was sepsis; a correct diagnosis of salicylate intoxication was not established until between 16 h and 10 days after admission in these four cases. Two patients died, one patient required permanent hemodialysis, and two patients recovered fully only after prolonged and complicated hospitalizations. The pathogenesis of this syndrome is uncertain. In two cases, serum levels of TNF-alpha, IL-1 beta and IL-6 were measured by ELISA. In both cases serum IL-6 was markedly increased, and in one case serum TNF-alpha was also elevated.Occult salicylate intoxication should be considered when apparent sepsis syndrome occurs without a readily easily identifiable source of infection. |
| 1991 | Sequential release of tumour necrosis factor, platelet activating factor and eicosanoids during endotoxin shock in anaesthetized pigs: protective effects of indomethacin. | Br J Pharmacol | 1. The effects of indomethacin were investigated on haemodynamics, haematological and blood glucose values, and the release of tumour necrosis factor (TNF), platelet activating factor (PAF) and eicosanoids in anaesthetized pigs receiving 5 micrograms kg-1 E. coli lipopolysaccharide (LPS) over 60 min into the superior mesenteric artery. The animals were observed for an additional period of 2 h after the termination of LPS infusion. 2. Eight of the 17 animals infused with LPS and not treated with indomethacin died within 30 min after the beginning of LPS infusion (non-survivors), while the other 9 survived the experimental period of 3 h though in a state of shock (survivors). 3. No alterations were observed in plasma concentrations of PAF and eicosanoids (thromboxane B2 (TXB2), 6-keto prostaglandin F1 alpha (6-keto PGF1 alpha) and leukotriene B4 (LTB4] in non-survivors. However, a marked increase was detected in TNF release. A significant, though transient, increase in concentrations of PAF, TNF and eicosanoids occurred in the survivors. The peak in the concentrations of PAF and TXB2 preceded the maximum in TNF values in survivors. 4. Another group of 7 LPS-infused pigs was treated with indomethacin (2 mg kg-1, i.v. bolus 60 min before the start of LPS infusion, followed by a continuous infusion of 3 mg kg-1 h-1). This treatment prevented death and shock despite the high concentrations of circulating TNF and PAF. Concentrations of cyclo-oxygenase enzyme products were reduced, whereas LTB4 release was not affected. The effect of indomethacin on haemodynamic changes occurred earlier than on cyclo-oxygenase products.5. In another group of 6 pigs indomethacin (2mg kg- 1, i.v.) was given 20-25 min after the start of LPS infusion at which time mean arterial blood pressure (MABP) had decreased below 40mmHg indicating imminent death. This indomethacin treatment immediately reversed the hypotension, restored the organ perfusion, delayed the haemoconcentration and thrombocytopenia and prevented death. However, TNF and PAF concentrations remained elevated. Concentrations of cyclo-oxygenase products studied were reduced by the end of the observation period, whereas LTB4 production was unaffected.6. The decrease in MABP induced by exogenous PAF was temporarily prevented by indomethacin.7. These data indicate that the beneficial effect of indomethacin in LPS-induced septic shock is related to cyclo-oxygenase inhibition as well as to a direct vasoconstrictor property of the drug. |
| 1991 | A Southwest Oncology Group phase II Trial of recombinant tumor necrosis factor in metastatic breast cancer. | Cancer | New approaches are needed in the treatment of advanced breast cancer. In vitro studies have shown that recombinant tumor necrosis factor (TNF) is a growth inhibitor for the MCF-7, ZR-75-1, and BT-20 human breast cancer cell lines. Based on these considerations, the Southwest Oncology Group performed a Phase II trial of recombinant TNF (Genentech) (150 micrograms/m2) given by 30-minute intravenous infusion on days 1 to 5 of every other week for 8 weeks. Patients with metastatic breast cancer who had received one prior chemotherapy regimen for advanced disease were eligible. Of the 22 patients who were entered, 3 were ineligible. Nineteen patients who had a performance status of 2 or less could be examined (median age, 53 years). One possible fatal toxic reaction has been seen in a patient who had intracranial bleeding caused by a previously undiagnosed brain metastasis; no other treatment-related deaths have occurred. Toxicity has included nausea, vomiting, fever, chills, myalgia, and fatigue. No Grade 4 toxicity has been observed. Grade 3 toxic reactions have included hypotension (two patients), diarrhea (one patient), transient leukopenia (two patients), and reversible elevations of liver function test values (two patients). No objective responses have been observed. Twelve of 19 patients have died (median survival time, 8.5 months). Recombinant TNF is inactive as a single agent in patients with previously treated metastatic breast cancer. |
| 1991 | [Cardioangioimmunology: the immune implications in the principle cardiovascular pathologies]. | G Ital Cardiol | At present, it is known that the immune system acts through the release of protein factors, so-called cytokines. In addition to their immunomodulating and endocrinometabolic effects, cytokines have appeared to be able to have an influence on the cardiovascular system by inducing important haemodynamic changes. Cytokines cause hypotension, particularly IL-2 and TNF, due at least in part to a production of nitric oxide by endothelial cells. Cytokines, such as IL-1, IL-6 and TNF, stimulate myocardial infiltration by activating leukocytes and inducing the release of cytotoxic factors during myocardial infarction; that would extend the area of necrosis. Finally, cytokines would be involved in the pathogenesis of the atherosclerosis, and cholesterol metabolism itself would be under a cytokine control. On these bases, it is possible to suggest in the near future the elaboration of new therapeutic strategies and prognostic indications, according to the bioimmunological response of patients with cardiovascular diseases. |
| 1991 | Local treatment of liver metastases with recombinant tumour necrosis factor (rTNF): a phase one study. | Neth J Surg | Fifteen patients with therapy-resistant liver metastases were treated in a phase-I study with recombinant human TNF (rTNF). The rTNF was injected into one liver metastasis by ultrasound guidance, using a 50 microgram escalating dose schedule (3 patients/dosage) ranging from 100-350 micrograms/injection. Influenza-like symptoms like fever, chills, nausea and vomiting were the main clinical side effects. Two patients, treated concomitantly with rTNF and morphine, showed mild hypotension. Other toxicities, as reported after systemic use of rTNF, such as decrease in leukocyte and platelet counts, renal or liver toxicity were not observed. In eight patients growth arrest was observed in rTNF-treated metastases, whereas non-injected lesions showed growth progression. The maximum tolerated dose by this route of administration is greater than 350 micrograms/injection. Based on these observations it is concluded that the toxicity of rTNF injected into liver metastases by sonographic control is transient and mild and that intratumoural administration of rTNF might play a role in local tumour control. |
| 1991 | Treatment with recombinant human tumor necrosis factor-alpha protects rats against the lethality, hypotension, and hypothermia of gram-negative sepsis. | J Clin Invest | Tumor necrosis factor (TNF) is a peptide secreted by macrophages in response to endotoxin that can produce many of the changes seen in septic shock. After cecal ligation and puncture (CLP) rats gradually develop tachycardia, hypotension, tachypnea, and hypothermia. At 5 h post-CLP, rats have a peak in serum levels of endotoxin and 60% of rats have blood cultures that grow Gram-negative rods (Escherichia coli and Klebsiella pneumonia). At 20 h post-CLP all rats develop positive blood cultures. Serum levels of TNF are not reproducibly measurable in rats following CLP. Rats undergoing CLP have a 50-80% mortality with deaths usually occurring 24-72 h postinjury. Repetitive (twice daily x 6 d) i.p. injection of sublethal doses of recombinant human TNF-alpha (100 micrograms/kg) to rats undergoing CLP 1 d after the treatment period resulted in a significant reduction in mortality compared to control rats previously unexposed to rTNF (P less than 0.03). Animals treated with rTNF had no hypotension or hypothermia after CLP and regained normal food intake faster than control rats. 12 h after CLP the gene expression for manganous superoxide dismutase (MnSOD), an inducible mitochondrial metalloenzyme responsible for cellular resistance to injury from toxic reactive oxygen species, was higher in livers of rats treated with rTNF suggesting that the TNF treatment augmented expression of this protective enzyme. Unlike MnSOD, expression of the gene for copper-zinc SOD was not affected by CLP or rTNF treatment. The results suggest that prior treatment with recombinant TNF can ameliorate the lethality, hypotension, hypothermia, and anorexia of Gram-negative sepsis in rats and that the mechanism may be related to enhanced hepatic expression of the gene for MnSOD. Repeated administration of recombinant TNF may be a strategy to minimize mortality and morbidity of Gram-negative sepsis. |
| 1991 | Priming by platelet-activating factor of endotoxin-induced lung injury and cardiovascular shock. | Circ Res | Platelet-activating factor (PAF) is a glycerophospholipid known for its unusual potent vasoactive and proinflammatory activities. The present study examined whether PAF might serve as a priming factor in endotoxin-induced tumor necrosis factor-alpha (TNF alpha) synthesis, cardiovascular shock, and lung injury in anesthetized rats. Intravenous infusion of PAF (1 pmol/kg/min for 60 minutes, n = 5) alone or endotoxin (0.1 micrograms/kg i.v. bolus, n = 5) failed to alter blood pressure, serum TNF alpha and thromboxane B2, platelet and leukocyte count, and hematocrit, nor was lung histology, myeloperoxidase activity, and water content changed. In contrast, the combined administration of PAF and endotoxin markedly elevated serum TNF alpha (1,359 +/- 362 pg/ml, n = 5, p less than 0.01) and thromboxane B2 (43 +/- 5 pg/100 microliters, n = 8, p less than 0.01) along with hypotension, hemoconcentration, leukopenia, and thrombocytopenia. Most notably, the combined regimen caused neutrophil aggregation, adhesion, and accumulation into the lung parenchyma along with platelet-fibrin deposits in postcapillary venules, pulmonary edema, and increased lung myeloperoxidase activity. The role of PAF in this process was confirmed by 1) the prevention of the priming effect by pretreatment with the PAF antagonist BN 50739 (n = 5), and 2) the failure of lyso-PAF, the cardinal nonactive PAF-metabolite, to prime for endotoxin-induced production of TNF alpha (n = 4). These data suggest that PAF could serve as a key mediator in priming for endotoxin-induced tissue injury, especially the typical pulmonary pathophysiology of adult respiratory distress syndrome, a severe pathological outcome of septic shock, burns, and multiple organ injury. |
| 1991 | Elevated plasma interleukin-6 and increased severity and mortality in alcoholic hepatitis. | Clin Exp Immunol | Recent studies in alcoholic hepatitis have proposed a role for the cytokine tumour necrosis factor-alpha (TNF-alpha) a mediator of endotoxic shock in sepsis. In this study plasma levels of the closely related cytokine interleukin-6 (IL-6) were assayed in 96 samples from 58 patients with severe alcoholic hepatitis, and 69 patients in control groups (21 normal, 10 alcoholic without liver disease, 10 inactive alcoholic cirrhosis, 18 chronic liver disease, 10 chronic renal failure). Plasma IL-6 levels were markedly elevated in patients with alcoholic hepatitis when compared with all control groups (P less than 0.001). IL-6 levels were higher in patients who died (P = 0.04) and correlated with the features of severe disease including: increased grade of encephalopathy, increased neutrophil count, increased prothrombin ratio, hypotension, increased serum creatinine and increased serum bilirubin. Surprisingly, no correlation was found between levels of plasma IL-6 and plasma TNF-alpha or endotoxin, or the presence of infection; an inverse correlation was found between plasma IL-6 and serum globulins. These findings provide further evidence that the IL-6/TNF cytokine system is activated in severe alcoholic hepatitis and may mediate hepatic or extra-hepatic tissue damage. |
| 1991 | Staphylococcus epidermidis induces complement activation, tumor necrosis factor and interleukin-1, a shock-like state and tissue injury in rabbits without endotoxemia. Comparison to Escherichia coli. | J Clin Invest | Tumor necrosis factor (TNF) and IL-1 are thought to mediate many of the pathophysiologic changes of endotoxemia and Gram-negative bacteremia. In these studies, heat-killed Staphylococcus epidermidis were infused into rabbits to determine whether an endotoxin (LPS)-free microorganism also elicits cytokinemia and the physiologic abnormalities seen in Gram-negative bacteremia. S. epidermidis induced complement activation, circulating TNF and IL-1, and hypotension to the same degree as did one-twentieth the number of heat-killed Escherichia coli. Circulating IL-1 beta levels had a greater correlation coefficient (r = 0.81, P less than 0.001) with the degree of hypotension than TNF levels (r = 0.48, P less than 0.02). Leukopenia, thrombocytopenia, diffuse pulmonary capillary aggregation of neutrophils, and hepatic necrosis with neutrophil infiltration were observed to the same extent after either S. epidermidis or E. coli infusion. However, S. epidermidis infusion did not induce significant (less than 60 pg/ml) endotoxemia, whereas E. coli infusion resulted in high (11,000 pg/ml) serum endotoxin levels. S. epidermidis, E. coli, LPS, or S. epidermidis-derived lipoteichoic acid (LTA) induced TNF and IL-1 from blood mononuclear cells in vitro. E. coli organisms and LPS were at least 100-fold more potent than S. epidermidis or LTA. Thus, a shock-like state with similar levels of complement activation as well as circulating levels of IL-1 and TNF were observed following either S. epidermidis or E. coli. These data provide further evidence that host factors such as IL-1 and TNF are common mediators of the septic shock syndrome regardless of the organism. |
| 1991 | Human interleukin-1 induces a rapid relaxation of the rabbit isolated mesenteric artery. | Br J Pharmacol | 1. Strips of rabbit superior mesenteric artery, precontracted with phenylephrine, relaxed when exposed to human recombinant interleukin-1 (IL-1) of the alpha or beta types. The effect was observed within 10 min, was optimal 32 min after the application of the cytokines and concentration-dependent (12-290 pM). 2. IL-1 alpha and IL-1 beta were equipotent in relaxing the rabbit mesenteric artery. A synthetic fragment corresponding to IL-1 beta 163-171 was approximately one million fold less active than IL-1 beta. The tripeptide Lys-D-Pro-Thr, an analogue of IL-1 beta 193-195, was inactive as an antagonist of IL-1 beta on the preparation. 3. Indomethacin (2.8 microM) prevented or acutely reversed IL-1-induced relaxations in the rabbit mesenteric artery. Purified haemoglobin (10 microM) or the removal of endothelium had no effect on relaxations elicited by IL-1 beta. 4. The preparation exhibited some selectivity for IL-1 as recombinant human tumour necrosis factor-alpha (TNF-alpha), IL-2 or IL-6 failed to influence it. TNF-alpha was not synergistic with a subthreshold concentration of IL-1 beta. 5. Immunoreactive 6-keto-prostaglandin F1 alpha and prostaglandin E2 were increased in the bathing fluid of isolated mesenteric arteries exposed to IL-1 beta as compared to controls. 6. A supernatant of lipopolysaccharide-stimulated human monocytes produced a relaxation of the preparation with a profile similar to that produced with IL-1s and there was a good quantitative agreement between the extent of the relaxation and the enzyme immunoassay measurements of IL-1 alpha and IL-1 beta in the supernatant.Furthermore the relaxation of crude monocyte IL-i was prevented by preincubating with antibodies to IL-l alpha and IL-1 beta. This experiment illustrates the possible use of the preparation for bioassay of IL-1. 7. It is concluded that either form of IL-I relaxes the precontracted rabbit mesenteric artery by a prostaglandin-dependent, nitric oxide-independent mechanism. The model is also useful for distinguishing the mechanism of IL-1-induced hypotension in vivo in rabbits. |
| 1991 | Biological and clinical effects of intravenous tumor necrosis factor-alpha administered three times weekly. | Cancer Res | Tumor necrosis factor (TNF) is a cytokine with pleiotropic biological and antitumor effects in vitro and in mouse models. The immunological effects of the molecule as a single agent, however, have not been well studied clinically. We conducted a Phase I trial of TNF in 53 patients with advanced malignancies in order to determine the biological and clinical effects of TNF when administered as a 30-min i.v. infusion three times/week. Dose levels of TNF ranged from 5 to 275 micrograms/m2; doses of TNF were escalated between patient groups. The most common clinical toxicities of TNF consisted of rigors, anorexia, headache, and fatigue. Dose-limiting toxicity consisted of hypotension, fatigue, and nausea. Four patients treated at the maximally tolerated dose of 225 micrograms/m2 received dexamethasone to determine whether the toxicities of TNF could be ameliorated. No significant differences in hypotension or subjective symptomatology were observed in those patients receiving dexamethasone and those who did not or between injections in which dexamethasone was administered and when it was not. One patient with colorectal carcinoma treated with 50 micrograms/m2 had a partial response lasting about 9 months. Biological responses were evaluated in 8 patients treated at the maximally tolerated dose before therapy and 24 h afterward. TNF significantly (P less than 0.05 for all) enhanced serum beta 2-microglobulin, serum neopterin, and serum interleukin-2 receptor (Tac antigen) levels. Indoleamine 2,3-dioxygenase activity was also increased 24 h following the administration of TNF, although this increase was only of borderline statistical significance (P = 0.07). TNF did not enhance granulocyte bactericidal activity. The expression of cell surface proteins on monocytes, including HLA-DR, HLA-DQ, beta 2-microglobulin, and the Fc receptor, and serum interleukin-1 activity also were not significantly increased by the administration of TNF. Thus, in humans TNF caused biological response modulation with evidence of HLA Class I (beta 2-microglobulin) increase and T-cell (Tac antigen) and monocyte (neopterin) activation. |
| 1991 | Group B streptococcus induces tumor necrosis factor in neonatal piglets. Effect of the tumor necrosis factor inhibitor pentoxifylline on hemodynamics and gas exchange. | Am Rev Respir Dis | Group B streptococcus (GBS), a common neonatal gram-positive pathogen, causes similar pathophysiologic features in human newborns and neonatal animal models of sepsis. Previous reports suggest that mediators in addition to TxA2 and PGI2 contribute to the late effects of GBS infusion (2 to 4 h), which include persistent increases in Ppa, hypoxemia, systemic hypotension, and a progressive fall in CO. Tumor necrosis factor (TNF) infusion in animals produces several of the late GBS effects. We hypothesized that GBS causes increased serum TNF levels 2 to 4 h into infusion in neonatal piglets. We also postulated that the TNF inhibitor, pentoxifylline (PTF), would attenuate both GBS-induced TNF production and late GBS effects. In piglets infused with 1.25 x 10(9) cfu/kg/h of GBS, serum TNF levels (pg/ml, ELISA assay) significantly increased at 2 h (231 +/- 41) and at 4 h (1,047 +/- 290, n = 9). In piglets infused with concomitant GBS + PTF, serum TNF levels at 4 h (208 +/- 39, n = 8) were reduced compared to GBS alone piglets (p less than 0.02). Control piglets infused with 0.9% saline or PTF alone for 4 h had no detectable serum TNF (less than 35). GBS alone and GBS + PTF infusion caused similar increases in serum TxB2 levels at 1, 2, and 4 h. Serum 6-keto-PGF1 alpha levels (pg/0.1 ml) significantly increased at 4 h (85 +/- 18) with GBS alone, and were more elevated at 4 h (306 +/- 75) with GBS + PTF infusion.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1991 | A specific receptor antagonist for interleukin 1 prevents Escherichia coli-induced shock in rabbits. | FASEB J | Despite antibiotic therapy, the septic shock syndrome continues to have a high mortality. Tumor necrosis factor (TNF) and interleukin 1 (IL 1), two polypeptide cytokines produced during sepsis, are thought to mediate the hypotension and tissue damage of shock. In the present studies, rabbits were infused with Escherichia coli organisms to produce shock. The IL 1 receptor antagonist (IL 1ra), which competes with IL 1 for occupancy of the IL 1 cell-surface receptors without agonist properties, was given 15 min before the bacterial infusion and during the subsequent 4 h. In saline-treated controls, hypotension was sustained for 4 h and death occurred for two of five rabbits; in rabbits treated with the IL 1ra, however, blood pressure was only transiently decreased, returned to pre-E. coli levels, and no deaths occurred. The associated leukopenia was also reduced by treatment with the antagonist (P less than 0.05). Histological examination of lung tissues showed reduced infiltrating neutrophils in the IL 1ra treatment group. Despite the attenuated responses in animals treated with the IL 1ra, circulating TNF and IL 1 levels were nearly identical in both groups. We conclude that specific blockade of IL 1 at the receptor level demonstrates an essential role for this cytokine in the pathogenesis of septic shock. |
| 1991 | Comparative and interactive in vivo effects of tumor necrosis factor alpha and endotoxin. | Circ Shock | A comparative and interactive analysis of the effects of tumor necrosis factor alpha (TNF) and endotoxin (ETX) on selected hemodynamic and glucoregulatory alterations was performed in conscious, unrestrained, adult male Holtzman rats. Rats with indwelling carotid artery and jugular vein cannulae were administered intravenous (i.v.) bolus injections of either (1) ETX at 1.55 or 30 mg/kg; (2) TNF at 0.1, 0.5, or 1.0 mg/kg; or (3) TNF plus ETX as a low dose co-treatment at 0.1 mg/kg plus 1.55 mg/kg, respectively. Control groups received either saline or heat-inactivated TNF. TNF induced a lethal response such that 1.0 mg/kg resulted in five out of six deaths within 6 hr. Elevated pulse rates, early hyperglycemia, late hypoglycemia, hyperlactacidemia, hypoinsulinemia, and elevated catecholamine concentrations were evident after injection of 1.0 mg/kg TNF. The pathophysiological alterations observed after 1.0 mg/kg TNF were comparable to the changes observed after the administration of a highly lethal, 30 mg/kg dose of ETX (six out of six deaths within 24 hr). Co-treatment with low doses of TNF plus ETX resulted in the rapid demise of the rats, resulting in six out of six deaths within 4 hr. The resultant shocklike state was accompanied by significant hypotension, hyperglycemia and hyperlactacidemia, similar to the changes induced by highly lethal doses of TNF or ETX alone. This study supports the involvement of TNF in the pathogenesis of gram-negative septic shock and documents the hemodynamic and glucoregulatory alterations which accompany the exacerbated shocklike state induced after co-treatment with separately, minimally lethal doses of TNF plus ETX. |
| 1991 | Effects of stress on cytokine production. | Methods Achiev Exp Pathol | Physiologic stress results in significant alterations in the release of multiple cytokines. Increased production of interleukin-1 (IL-1) occurs following hemorrhage and thermal injury. Hemorrhage, accidental trauma and burns are followed by decreased interleukin-2 (IL-2) generation. Production of interleukin-3 (IL-3) and interleukin-5 (IL-5) is diminished following hemorrhage. Gamma-interferon release appears to be increased following hemorrhage. Stress secondary to infection is accompanied by marked elevations in serum levels of tumor necrosis factor (TNF), which contribute to hypotension and physiologic instability in this setting. Alterations in cytokine release probably play important roles in mediating alterations in immunologic, hemodynamic and cardiorespiratory function known to occur following physiologic stress. The production of all cytokines so far examined is altered by stress. Increased generation of IL-1, and probably of TNF and IL-6, contributes to the acute-phase reaction and hypermetabolic response which accompanies injury, burns, hemorrhage, and overwhelming infection. Severe immunosuppression, involving both T and B cell function, and contributing to the increased incidence of infection after injury may result, at least in part, from the multiple actions of stress-induced alterations in interleukin release. T cell activation is clearly affected by injury-induced decreases in IL-2, IL-3, and IFN-gamma release. Similarly, the depressed generation of systemic and mucosal antibodies to bacterial antigens following injury may be affected by alterations in the production of cytokines affecting B cell function, namely IL-1, IL-2, IL-3, IL-5 and IFN-gamma.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1991 | Phase I trial of recombinant human tumour necrosis factor alpha in patients with advanced malignancy. | Eur J Cancer | A phase I clinical trial was conducted with recombinant human tumour necrosis factor alpha (rhTNF-alpha) in 62 patients with advanced malignancy refractory to previous standard therapy. rhTNF-alpha was given as a 30 min infusion twice a day at 6 h intervals. A total of 10 different dose levels was escalated in cohorts of 6 patients ranging from 2.5 to 200 micrograms/m2 twice a day for 5 days every second week for a total of 8 weeks followed by a 4-week observation period. Major side-effects of TNF-alpha therapy, seen in almost all patients studied, were fever and chills. As dose-limiting side-effects hypotension and liver toxicity were recorded in 4 of 5 patients treated with 200 micrograms/m2 twice a day. Pharmacokinetic studies revealed a TNF-alpha serum half-life of 13 to 25 min, a dose-dependent decrease in TNF clearance, and a dose-dependent increase in the area under the time/concentration curve. No anti-TNF-alpha antibodies could be detected, except in 1 patient. Tumour response to TNF treatment was poor. Only in 3 of 57 evaluable patients was partial tumour regression observed. |
| 1991 | Recombinant tumour necrosis factor alpha administered subcutaneously or intramuscularly for treatment of advanced malignant disease: a phase I trial. | Eur J Cancer | The pharmacokinetics, toxicity and biological effects of subcutaneous and intramuscular treatment of cancer patients with recombinant tumour necrosis factor alpha (rTNF-alpha) was investigated. 17 patients suffering from refractory malignant disease were treated with either 1.0 micrograms/m2, 10 micrograms/m2 or 100 micrograms/m2 rTNF-alpha. Vital signs, peripheral blood cell counts, TNF and interferon (IFN) gamma serum levels, neopterin, beta 2-microglobulin, C reactive protein (CRP) and cortisol levels were measured immediately before and 2, 12, 24, 48 and 168 h after the first administration of rTNF-alpha. Tumour response was evaluated after 4 and 12 weeks of treatment. The pharmacokinetics followed the same characteristics as those reported for other cytokines. Major toxicities were dose dependent and comprised fever, constitutional symptoms and hypotension. TNF dependent changes were observed in serum levels of IFN-alpha, CRP, neopterin, beta 2-microglobulin, cortisol and white blood cell counts. No objective tumour response was observed. This study indicated that rTNF-alpha administered subcutaneously or intramuscularly results in measurable TNF serum levels, significant toxicity and biological response in absence of clinical efficacy in patients with advanced cancer. |
| 1991 | Production of tumor necrosis factor alpha and interferon gamma in interleukin-2-treated melanoma patients: correlation with clinical toxicity. | Cancer Immunol Immunother | Interleukin-2 (IL-2)-based immunotherapy regimens are accompanied by dose-limiting toxicity consisting of fever, tachycardia, chills and capillary leak syndrome. We hypothesized that the toxicity was caused by the induction and release of endogenous cytokines such as tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma). We measured the serum levels of TNF alpha and IFN gamma in IL-2-treated melanoma patients and attempted a correlation with clinical toxicity. A total of 23 patients received either 6 x 10(6) IU or 12 x 10(6) IU Cetus IL-2/m2 by i.v. bolus daily for 5 consecutive days on weeks 1, 3 and 5. Serum TNF alpha and IFN gamma levels were measured by enzyme-linked immunosorbent assay. Clinical toxicity was scored each day by objective measurements of hypotension, tachycardia, fever and chills/rigors. Clinical toxicity and IFN gamma levels correlated nicely, peaking on the 5th day of each treatment cycle. The kinetics and magnitude of TNF alpha production, however, were not predictable and did not correlate with either IFN gamma or toxicity. Some patients had modest increases in TNF alpha production while others had markedly increased levels during the second and third treatment weeks. Remarkably, these high levels persisted during nontreatment weeks and after completion of therapy. This clinical study demonstrates novel kinetics for immunoreactive TNF alpha in IL-2 cancer patients, which do not correlate well with toxicity. |
| 1990 | Inhibition of interleukin-2-induced tumor necrosis factor release by dexamethasone: prevention of an acquired neutrophil chemotaxis defect and differential suppression of interleukin-2-associated side effects. | Blood | High concentrations of tumor necrosis factor (TNF) alpha have been detected in the plasma of patients undergoing immunotherapy with interleukin 2 (IL-2), suggesting that this cytokine may play a role in the fever and shocklike state induced by the administration of high-dose IL-2. Dexamethasone has been shown to inhibit the synthesis of TNF by monocytes activated in vitro by endotoxin. To determine if dexamethasone can exert a similar suppressive effect on IL-2-induced TNF synthesis in vivo, the concentration of TNF alpha was measured in plasma samples serially obtained (a) from cancer patients participating in a phase I dose escalation clinical trial with high-dose IL-2 administered in conjunction with dexamethasone (IL-2/Dex) and (b) from patients participating in concurrent studies with IL-2 alone. In contrast to the high plasma levels of TNF alpha detected in patients receiving IL-2 alone, TNF levels in most of the IL-2/Dex patients remained below the threshold of detectability of our TNF radioimmunoassay. The concurrent administration of dexamethasone also prevented the IL-2-induced increase in serum levels of C-reactive protein, a hepatic acute phase reactant whose synthesis is regulated by proinflammatory cytokines such as TNF. The steroid-treated patients also failed to develop the neutrophil chemotactic defect characteristic of IL-2 recipients. The concomitant administration of dexamethasone increased the maximum tolerated dose of IL-2 approximately threefold and markedly reduced the hypotension and organ dysfunction ordinarily observed in these patients. These results demonstrate that dexamethasone inhibits the release of TNF into the circulation of patients undergoing immunotherapy with IL-2. They further suggest that the altered spectrum and reduced severity of IL-2 side effects observed in patients receiving dexamethasone may be attributable in part to the suppressive effect of steroids on IL-2-induced TNF synthesis. |
| 1990 | Platelet activating factor (PAF) and tumor necrosis factor-alpha (TNF alpha) interactions in endotoxemic shock: studies with BN 50739, a novel PAF antagonist. | J Pharmacol Exp Ther | BN 50739, a new PAF receptor antagonist, was tested in vitro and in vivo for its capacity to block PAF, endotoxin and recombinant human tumor necrosis factor-alpha (rTNF)-mediated effects. In vitro, BN 50739 blocked PAF-induced platelet aggregation by 60 to 100% at 0.2-1 x 10(-7) M (P less than .002), respectively. In the conscious rat, pretreatment (30 min) with BN 50739 (n = 5-13) dose-dependently attenuated PAF-induced hypotension (-5 +/- 5 vs. - 43 +/- 2 mm Hg, P less than .01) and shortened the recovery time of mean arterial pressure (22 +/- 13 vs. 325 +/- 46 sec, P less than .01). BN 50739 (10 mg/kg i.p., n = 5-11) prevented endotoxin (14.4 mg/kg) induced-hemoconcentration (54 +/- 1 vs. 46 +/- 1%, P less than .01) and reduced 24-hr mortality (100 vs. 60%, P less than .05). Only partial protection was conveyed by BN 50739 against the hypotensive response to endotoxin (115 +/- 3 vs. 91 +/- 4 mm Hg, P less than .03). Also, BN 50739 attenuated the lipopolysaccharide-induced elevation of plasma thromboxane B2 (21.2 +/- 0.8 vs. 46.7 +/- 11.8 pg/100 microliters, P less than .01) and tumor necrosis factor-alpha (7523 +/- 3983 vs. 26,430 +/- 3541 U/ml, P less than .05), whereas leukopenia and thrombocytopenia remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1990 | Tumor necrosis factor infusions in humans prime neutrophils for hypochlorous acid production. | Am J Physiol | Five cancer patients undergoing intravenous infusions of human recombinant tumor necrosis factor (TNF)alpha were evaluated for the effects these infusions had on the priming of circulating neutrophils for hypochlorous acid (HOCl) production. These patients were also studied for changes in temperature, circulating white blood cell counts, blood pressure, and spontaneous monocyte interleukin 1 beta (IL-1 beta) and TNF production. As predicted by previous in vitro studies, patient neutrophils increased their HOCl production to unopsonized zymosan from a baseline of 29.2 +/- 5.9 nmol I- oxidized/4 x 10(6) cells to a peak of 64.2 +/- 9.8 nmol I- oxidized/4 x 10(6) cells at 4 h after TNF infusion (P less than 0.01). Similar increases were also seen at 4 h with phorbol myristic acetate and opsonized zymosan as the stimuli. The priming effect could be reproduced in neutrophils from a normal individual by incubating them with the 30-min serum samples from the infused patients. The ability of this serum to prime neutrophils was completely blocked by a monoclonal anti-TNF alpha-antibody but not by an anti-IL-1 beta antibody. In addition to the priming of their neutrophils, patients also experienced fever, marked hypotension, and an initial fall, followed by rebound to an elevation, in circulating white blood cell counts. The TNF infusions did not produce detectable circulating IL-1 beta nor did they induce significant production of TNF or IL-1 beta by circulating blood monocytes. These studies confirm the role of TNF in producing the signs of sepsis such as hypotension, fever, and leukopenia followed by leukocytosis.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1990 | The role of the complement system in shock and tissue injury induced by tumour necrosis factor and endotoxin. | Immunology | It has previously been shown that tumour necrosis factor-alpha (TNF), together with bacterial lipopolysaccharide (LPS), induces shock and bowel necrosis in the rat. Since the complement system plays an important role in inflammation and tissue injury, its role has been studied in a similar model in mice. In most of the present experiments, a low dose (0.2 micrograms/g) of TNF was used for priming, followed 30 min later by LPS (3 micrograms/g), and the experiment was terminated in 150 min. It is shown that: (i) TNF exerts no systemic effects by itself; LPS elicits only mild hypotension but causes no lethality; (ii) TNF-primed mice show exaggerated effects of shock, hypothermia, haemoconcentration and bowel injury after LPS; the majority of these mice died within 150 min; (iii) administration of LPS alone mildly activates the complement system in vivo, while TNF alone has no effect; (iv) the effects of TNF and LPS on complement activation are synergistic; (v) the acute development of shock and bowel injury in response to TNF-LPS is dependent on an intact complement system, more specifically C5, since C5-deficient mice were protected from TNF-LPS-induced shock and tissue injury; C5-deficient mice also showed less hypotension, hypothermia, haemoconcentration and better intestinal perfusion compared with C5-sufficient animals; (vi) however, when the priming dose of TNF was raised to 0.5 micrograms/g, most of the C5-deficient mice developed marked hypothermia, hypotension, haemoconcentration, bowel injury and died. Thus, it is concluded that TNF and LPS act synergistically in activating the complement system, which plays an important role in mediating the tissue injury and lethality induced by these agents. |
| 1990 | Tumor necrosis factor-induced neonatal pulmonary hypertension: effects of dazmegrel pretreatment. | Pediatr Res | The endogenously produced cytokine, tumor necrosis factor-alpha (TNF-alpha), has been shown in adult animal models to be associated with many of the pathophysiologic effects of sepsis, including systemic hypotension and hemorrhagic necrosis. TNF-alpha can induce the release of various vasoactive arachidonic acid metabolites, suggesting that TNF-alpha may act either directly or via intermediary substances in producing its effects. The pathophysiologic role of TNF-alpha in neonatal sepsis, especially its potential effect on pulmonary vascular tone, is presently unknown. To assess the role of TNF-alpha in neonatal sepsis, 19 piglets (19 +/- 5 d old) were anesthetized, intubated, paralyzed, mechanically ventilated, and catheterized to assess pulmonary and systemic vascular hemodynamics and pulmonary gas exchange. The multiple inert gas elimination technique was used to assess ventilation perfusion matching. A 30-min infusion of human recombinant TNF-alpha (250 micrograms/kg total dose) was administered to animals pretreated with either 10 mg/kg dazmegrel, a thromboxane synthase inhibitor (n = 9) or placebo (n = 10). TNF-alpha alone induced a prompt and sustained rise in pulmonary arterial pressure and pulmonary vascular resistance that continued at least for 2 h after onset of the infusion. In contrast, the animals pretreated with dazmegrel demonstrated no rise in pulmonary vascular resistance until 2 h after the onset of the infusion. Neither group of animals demonstrated a significant decline in arterial PO2 or evidence from inert gas analysis of VA/Q mismatching or increase in intrapulmonary shunt.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1990 | NG-methyl-L-arginine inhibits tumor necrosis factor-induced hypotension: implications for the involvement of nitric oxide. | Proc Natl Acad Sci U S A | Clinical assessment of the activity of tumor necrosis factor (TNF) against human cancer has been limited by a dose-dependent cardiovascular toxicity, most frequently hypotension. TNF is also thought to mediate the vascular collapse resulting from bacterial endotoxin. The present studies address the mechanism by which TNF causes hypotension and provide evidence for elevated production of nitric oxide, a potent vasodilator initially characterized as endothelium-derived relaxing factor. Nitric oxide is synthesized by several cell types, including endothelial cells and macrophages, from the guanidino nitrogen of L-arginine; the enzymatic pathway is competitively inhibited by NG-methyl-L-arginine. We found that hypotension induced in pentobarbital-anesthetized dogs by TNF (10 micrograms/kg, i.v., resulting in a fall in mean systemic arterial pressure from 124.7 +/- 7 to 62.0 +/- 22.9 mmHg; 1 mmHg = 133 Pa) was completely reversed within 2 min following administration of NG-methyl-L-arginine (4.4 mg/kg, i.v.). In contrast, NG-methyl-L-arginine failed to reverse the hypotensive response to an equivalent depressor dose of nitroglycerin, a compound that acts by forming nitric oxide by a nonenzymatic, arginine-independent mechanism. The effect of NG-methyl-L-arginine on TNF-induced hypotension was antagonized, and the hypotension restored, by administration of excess L-arginine (100 mg/kg, i.v.). Our findings suggest that excessive nitric oxide production mediates the hypotensive effect of TNF. |
| 1990 | Effects of in vivo 'priming' on endotoxin-induced hypotension and tissue injury. The role of PAF and tumor necrosis factor. | Am J Pathol | Exogenously administered tumor necrosis factor-alpha (TNF) and bacterial endotoxin (LPS) induce shock and tissue injury. Here, the authors studied the effect of endogenous TNF on LPS-induced hypotension and tissue injury and investigated the role of PAF in these responses. Rats were primed with intraperitoneal injection of zymosan 24 hours before, or Bacillus Calmette-Guérin (BCG) 12 to 15 days before intravenous injection of low dose (0.5 mg/kg) LPS. It was found that nonprimed animals showed mild hypotension and moderate leukopenia in response to LPS. In contrast, zymosanprimed rats developed shock and marked leukopenia, and more severe bowel injury than nonprimed rats. The authors then showed that, following LPS injection, zymosan-primed animals had higher TNF and platelet-activating factor (PAF) levels than nonprimed rats. Pretreatment of the animal with PAF antagonist, SRI 63-441, markedly ameliorated the hypotension and tissue injury. Interestingly, BCG-primed rats did not show aggravation of LPS-induced hypotension. Only TNF (but not PAF) level in these animals was increased. Thus, it appears that TNF release alone, without a sufficient increase in PAF, is incapable of causing severe hypotension. However, most of the BCG-primed animals showed tissue injury, which could be prevented by pretreatment with PAF antagonist. The authors discuss the possible mechanisms of this discrepancy between systemic and local responses in BCG-primed animals. |
| 1990 | Local/regional recombinant interleukin 2 (rIL-2) immunotherapy of tumors. Intra-arterial continuous infusion of rIL-2 in bladder cancer patients: a phase I study. | Ann Ist Super Sanita | We have investigated clinical and immunological effects of two 5-day cycle continuous infusion of four escalating doses (3,000; 30,000; 300,000; 3,000,000 U/m2/day) of intra-arterial (i.a.) rIL-2, in ten patients with superficial (Ta-T1, N0, M0) bladder TCC. Tumor TUR was performed four days after the end of the second IL-2 cycle. No clinical or laboratory toxicity was detected in any but one patient, who developed grade III hypotension and grade III neurological toxicity. Two CR and two PR were observed in patients treated with 30,000 and 300,000 U/m2/day of rIL-2, respectively. Clinical responses lasted 8+, 8+, 4+ and 4+ months, respectively. Two out of ten patients developed recurrences two months after tumor resection. In the peripheral blood, no changes in the percentage of T (CD3+) lymphocytes were observed, while a significant increase of CD3+ CD16+ T cells was found in 6/9 patients. In contrast, NK (CD3- CD16+) cells were augmented only in 2/9 patients. An increase of B lymphocytes (CD19+ cells) and monocytes (CD14+ cells) was also observed in 3/9 and 7/9 patients, respectively. Lymphocyte activation marker expression (CD25, CD71, HLA-DR) increased mainly on T lymphocytes. NK and LAK activities were enhanced in 4/10 patients, while ADCC activity augmented in 2/10 patients. No detectable increased levels of plasmatic lymphokines (gamma-IFN and alpha-TNF) were found. Enhanced CD8+ and CD4+ tumor infiltrating lymphocytes were demonstrated after IL-2 treatment. Moreover, at the tumor site, lymphocytes expressing CD25 and HLA-DR antigens were noted. Tumor infiltrating macrophages were positive for IL-1 alpha, IL-1 beta and alpha-TNF. |
| 1989 | A phase I trial of subcutaneously administered recombination tumor necrosis factor to patients with advanced malignancy. | J Biol Response Mod | Nineteen patients with advanced cancer for which there was no effective standard therapy or whose disease was refractory to standard therapy were treated with recombinant tumor necrosis factor (rTNF). The rTNF was administered subcutaneously for 5 consecutive days every other week for 3 treatment weeks. The doses administered ranged from 5 micrograms/m2/day to 150 micrograms/m2/day. There was no intrapatient dose escalation. Systemic side effects of chills, fever, hypotension, nausea, vomiting, and headache were mild and self-limiting. At the maximum tolerated dose of 150 micrograms/m2/day, five of seven patients experienced moderate to severe thrombocytopenia. Mild rapid declines in total leukocyte count occurred within 60-90 min of administration of the drug, followed by a rise in the total leukocyte count by 120 min. When the total daily dose was administered in a single subcutaneous site, skin ulceration and necrosis occurred at the 100 micrograms/m2/day dose. By giving the total daily dose in two subcutaneous sites, the maximum tolerated dose increased to 150 micrograms/m2/day, and there was no further skin ulceration or necrosis. Skin necrosis occurred in the abdomen and thigh but not on the upper extremity at the 100 micrograms/m2/day dose given in a single site. There was no other significant organ toxicity. No rTNF was detectable in the serum even at the highest doses. No antibodies to TNF developed in any of the patients. The recommended dose of rTNF for Phase II trials given for 5 days subcutaneously is 150 micrograms/m2/day divided into two or more sites. |
| 1989 | Experience with the use of high-dose interleukin-2 in the treatment of 652 cancer patients. | Ann Surg | We have administered 1039 courses of high-dose interleukin-2 (IL-2) to 652 cancer patients. Five hundred ninety-six patients had metastatic cancer that either had failed standard effective therapies or had disease for which no standard effective therapy existed, and 56 patients were treated in the absence of evaluable disease in the adjuvant setting. IL-2 was administered either alone (155 patients) or in conjunction with activated immune cells such as lymphokine activated killer (LAK) cells (214 patients) or tumor infiltrating lymphocytes (TIL) (66 patients), with other cytokines such as alpha interferon (a-IFN)(128 patients) or tumor necrosis factor (TNF)(38 patients), with monoclonal antibodies (32 patients), or with the chemotherapeutic agent cyclophosphamide (19 patients). Initial results with the treatment of high-dose IL-2 alone or in conjunction with LAK cells have indicated that objective regressions of cancer can be achieved in 20% to 35% of patients with selected advanced metastatic cancers. Although most responses have been seen in patients with metastatic renal cell cancer, melanoma, colorectal cancer, and non-Hodgkin's lymphoma, many histologic types of cancer have not been treated in significant numbers. These regressions can be durable; of 18 patients achieving a complete response, ten have not experienced recurrence at intervals from 18 to 52 months. Although combinations of IL-2 with TNF do not appear to result in increased responses, there is a suggestion in our initial phase I studies that the combination of a-IFN and IL-2 is more effective than the administration of cytokine alone and this combination deserves further study. Similarly the adoptive transfer of TIL in conjunction with IL-2 also appears to be more effective than the use of IL-2 alone. The toxic side effects in patients treated with high-dose IL-2 are presented and include malaise, nausea and vomiting, hypotension, fluid retention, and organ dysfunction. Treatment-related deaths were seen in 1% of all treatment courses and in 1.5% of patients. These studies demonstrate that a purely immunologic manipulation can mediate the regression of advanced cancers in selected patients and may provide a base for the development of practical, effective biologic treatments for some cancer patients. |
| 1989 | A phase I trial of recombinant human tumor necrosis factor and interferon-gamma: effects of combination cytokine administration in vivo. | J Clin Oncol | The combination of tumor necrosis factor (TNF) and interferon-gamma has synergistic bioactivity in numerous preclinical model systems. We have tested this potential synergism in vivo by administration of both cytokines to patients with advanced cancer using overlapping 24-hour continuous intravenous (IV) infusions in a phase I trial. Thirty-six patients were treated with a fixed dose of interferon-gamma (200 micrograms/m2/d) with interpatient dose escalation of TNF (from 5 to 205 micrograms/m2/d). The dose-limiting toxicity at the maximal-tolerated dose (MTD) of TNF (205 micrograms/m2) with interferon-gamma was hypotension. Other toxicities noted included an influenza-like syndrome, transient decreases in circulating leukocyte and platelet counts, subclinical evidence of disseminated intravascular coagulation, and the sporadic occurrence of acute pulmonary toxicity. The recommended phase II dose for this combination schedule is TNF, 136 micrograms/m2, with interferon-gamma, 200 micrograms/m2. The addition of interferon-gamma to TNF resulted in a greater than three-fold increase in toxicity compared with TNF administered as a single agent, supporting the hypothesis that the combination of these cytokines may induce synergistic effects in vivo. |
| 1989 | Failure of tumor necrosis factor to produce hypotensive shock in the absence of endotoxin. | Surgery | Tumor necrosis factor (TNF) is reported to cause a shock syndrome similar to that produced by endotoxin (LPS). The purpose of this study was to determine the relationship between TNF and LPS in causing shock. Eighty rats received infusions of either TNF, LPS, or TNF plus LPS, as compared with saline solution. Temperature, blood, and tissue specimens were obtained at 2 hours. Blood pressure was measured over 4 hours in a separate group of awake rats. Mortality was assessed over 24 hours. Neither TNF (1 mg/kg) nor LPS (1 mg/kg) altered hematocrit, blood gases, temperature, or caused hypotension or mortality. If the same dose of TNF was combined with LPS, however, there was significant (p less than 0.05) hemoconcentration and metabolic acidosis associated with hypotension and 100% mortality by 4 hours. Pathologic changes were restricted to the small intestine and occurred in this group only. It was concluded that TNF does not cause hypotension or shock in the rat. TNF will cause lethal shock, however, if combined with a sublethal dose of endotoxin. This suggests that synergy between TNF and endotoxin is important in septic shock. |
| 1989 | [Transcatheter arterial embolization with hepatic arterial induction of endogenous TNF in hepatocellular carcinoma]. | Gan To Kagaku Ryoho | Antitumor effect and reduction of tumor size by some cytokines as Biological Response Modifier have been demonstrated by various studies. Endogenous tumor necrosis factor is produced from macrophage. To increase the antitumor effect of transcatheter arterial embolization (TAE) in hepatocellular carcinoma (HCC), we treated 7 HCC patients with endogenous tumor necrosis factor (ETNF) which was induced by hepatic arterial injection of gamma-IFN (1.0-3.0 X 10(6) IU) as priming agent and OK-432 (2-5 KE) as triggering agent. TAE was performed with Lipiodol, ADM and gelatin sponge on 3-10 days after the induction of ETNF. TNF activity was detected in 2 cases and suspected to depend on the dose of gamma-IFN and OK-432. Serum alpha-Fetoprotein levels after the injection of ETNF began to decrease from 3-30 days in 5 patients and remained unchanged in 2 cases. Serum alpha-Fetoprotein levels after TAE with the induction of ETNF were decreased 1-5 months in 5 cases. Reduced size and low-density area on CT scan in 3 advanced cases after these procedures were no different from those of HCC patients treated with TAE alone. In one of two inoperable cases with a single mass lesion in the liver, CT scan after one more added TAE following these procedures showed a low-density area around the Lipiodol uptaking tumor, indicating obstruction of the peripheral portal vein. CT scan of another case revealed low density around Lipiodol in the tumor, which showed complete necrotic change. In all cases, middle-grade fever and hypotension were seen transiently, but these subsided by symptomatic treatment. The antitumor effect of TAE in HCC might be enhanced with ETNF induced by hepatic arterial injection of a low dose of gamma-INF and OK-432. |
| 1989 | Circulating tumour necrosis factor-alpha (cachectin) in myocardial infarction. | J Intern Med | In a prospective study, 22 patients with prolonged chest pain were monitored by serial serum tumour necrosis factor-alpha (TNF; cachectin) measurements. In five patients serum TNF markedly increased, peaking at greater than 145 ng l-1; all these patients had large infarcts complicated by hypotension, pulmonary oedema and/or arrhythmia. Two of these patients died. In contrast, TNF levels were either normal or only slightly raised in patients with small or uncomplicated infarcts and in patients with prolonged angina without evidence of infarction. The results show that extensive myocardial infarction induces the release of the monocyte/macrophage-derived polypeptide hormone TNF into circulation. This finding may be clinically relevant with respect to systemic metabolic consequences of myocardial infarction. |
| 1989 | The effects of tumor necrosis factor and their selective inhibition by ibuprofen. | Ann Surg | High doses of tumor necrosis factor (TNF) cause hypotension, metabolic acidosis and, death. At Brigham and Women's Hospital, the effects of a sublethal, 6-hour infusion of TNF (0.57 X 10(5) Units/kg body weight) in twelve anesthetized dogs were studied. The dose caused falls in mean arterial pressure from 153 mmHg to 96 mmHg, pulmonary artery pressure (-4.5 mmHg), central venous pressure (-2.5 mmHg) and pulmonary capillary wedge pressures (-5.25 mmHg). Associated with these responses were a fourfold increase in urine volume (22.4 ml/kg/6 hours as compared to 5.2 ml/kg/6 hours in controls), significant pyrexia (from 38.1 C to 39.5 C, rectal), tachycardia (from 125 to 175 beats/minute), and hypermetabolism. In addition, leukopenia and increased circulating stress hormone concentrations were observed. Blood glucose concentrations fell from 4.68 mM/1 to 3.97 mM/1 (84-71 mg/dl) within 3 hours of TNF infusion, whereas lactate and pyruvate concentrations increased. These alterations occurred in the absence of severe hypotension or acidosis and were similar to changes observed after endotoxin administration or gram-negative septicemia. Pretreatment of the animals with the cyclooxygenase inhibitor ibuprofen abolished most of the hemodynamic changes and attenuated other responses. These findings support the hypothesis that TNF is an important mediator of septic responses and that some of the effects of TNF are mediated via cyclooxygenase pathways. |
| 1989 | A phase I clinical trial of recombinant human tumor necrosis factor given daily for five days. | Cancer Chemother Pharmacol | A phase I trial of human recombinant tumor necrosis factor (rH-TNF) has been carried out in patients with advanced solid tumors. Sixty-six courses of the drug were given by 1 h IV infusion, daily for 5 days to 33 patients at doses of 5, 10, 20, 30, 45, 60, and 80 x 10(4) U/m2/day. All patients received isotonic saline (up to 21/day) and either indomethacin or ketoprofen. Acute toxicity resembled that seen with the phase I study of a single dose (5). Dose limiting toxicity was acute, rapidly reversible, hepatic dysfunction and hypotension. Hypertension during drug infusion and dyspnea were marked in some patients. There was one complete and one minor response, both in patients with renal cell carcinoma. The dose of 80 x 10(4) U/m2/day x 5 was poorly tolerated and the recommended starting dose for phase II studies is 60 x 10(4) U/m2/day x 5. Caution is recommended in treating patients with pre-existing hepatic function abnormalities, hypertension, hypotension or significant obstructive airway disease. |
| 1989 | Intravenous recombinant tumor necrosis factor in the treatment of AIDS-related Kaposi's sarcoma. | J Acquir Immune Defic Syndr (1988) | Tumor necrosis factor (TNF) has demonstrated antitumor activity against a variety of tumors and is particularly cytotoxic to capillary endothelial cells, which are the presumed cell of origin of Kaposi's sarcoma. We evaluated the toxicity and clinical antitumor and antiretroviral effects of recombinant TNF administered at a once weekly dose of 100 micrograms/m2 intravenously for 8 weeks in five men with AIDS-related Kaposi's sarcoma and without prior opportunistic infection. One patient was removed from study at week 4 due to rapid progression of Kaposi's sarcoma, another patient with stage IV disease and a pretreatment CD4 count of 11 developed fever, hypotension, and pneumonia at week 7 and died 8 days after discontinuing recombinant TNF. No pathogenic organisms were isolated. He had marked eschar formation of his Kaposi's sarcoma lesions, particularly in areas previously exposed to radiation therapy. Uniform toxicities included fevers, rigors, and headaches during drug infusion that were ameliorated by prophylactic meperidine hydrochloride and acetaminophen. All experienced fatigue and three had arthralgias. One patient had transient hypotension which corrected with i.v. fluids. No significant hematologic, hepatic, or renal toxicities were seen. All patients had some progression of their Kaposi's sarcoma on study. There was no change in CD4 or CD8 count or in CD4:CD8 ratios. Serum human immunodeficiency virus (HIV) p24 antigen levels increased greater than 50% in three patients. We conclude that, as a single agent, at a dose of 100 micrograms/m2 recombinant TNF by i.v. infusion has no obvious antitumor or antiretroviral effects in patients with AIDS-related Kaposi's sarcoma. |
| 1989 | Phase II clinical trial of high-dose recombinant human tumor necrosis factor. | Cancer Chemother Pharmacol | Based on a phase I study in 1986, 22 patients have been entered in a phase II study of high-dose human tumor necrosis factor (rH-TNF) since May 1987. Of these patients, 18 are evaluable at present, 2 are still under investigation, and 2 have dropped out. All had advanced stages of cancer (9 soft-tissue sarcomas, 3 melanomas, 5 hypernephromas) and inclusion in the study was ethically acceptable (informed consent). The daily dose of rH-TNF was 15 x 10(5) units/m2, escalated to 21 x 10(5) units/m2 (683-956 micrograms/m2 every week; range 1-6 cycles). Additional prophylactic ketoprofen administration was carried out. Of the 18 evaluable patients, 4 responded with no change (2/4, clinical improvement) and 14 showed progressive disease. The main toxicities observed were hypotension (decrease in systolic blood pressure, 21-60 Torr), leukocytosis, increases in ALAT/ASAT (WHO grade 0-4), fever (WHO grade 1-2), chills (mild to moderate), neurotoxicity (WHO grade 0-2), and nausea/vomiting (WHO grade 0-3). |
| 1989 | Phase I study of recombinant human tumor necrosis factor alpha in advanced malignant disease. | Cancer Immunol Immunother | A phase I study with recombinant human tumor necrosis factor alpha (rhuTNF-alpha; Knoll AG, Ludwigshafen, FRG) in patients with advanced malignant disease was undertaken to evaluate drug toxicity (organ specificity, time course, predictability, reversibility, maximal tolerated dose), effectiveness, antigenicity and pharmacokinetics. TNF was administered as a test dose followed by daily i.v. infusions for 5 days, every 3 weeks (single i.v. infusion lasting 10 min, TNF dissolved in 50 ml 5% human albumin). Dosage was increased in groups of 3 or 4 patients from 0.04 mg/m2 to 0.28 mg/m2. A total of 19 patients with different cancers, including seven large-bowel carcinomas, three chronic myelogenous leukemias, three hypernephromas, two small-cell lung cancers, one malignant melanoma, one malignant lymphoma, one rhabdomyosarcoma and one fibrosarcoma were treated. Major side-effects were chills and fever (maximum 40.4 degrees C, median 38.7 degrees C, 19/19), headache (12/19), nausea and vomiting (12/19) and pronounced (greater than 20%) hypotension (4/19). Acute side-effects could be diminished by paracetamol or indomethacin pretreatment, and with one possible exception no tachyphylaxis to TNF was noted. Mild renal toxicity was seen during TNF treatment. Pharmacokinetic studies showed a serum half-life (t1/2) ranging from 11 min to 17 min for doses from 0.04 mg/m2 to 0.16 mg/m2 and prolonged clearance with t1/2 ranging from 54 min to 70 min in the 0.20-0.28 mg/m2 dose range. No objective antitumor effects were observed in this phase I study. |
| 1989 | Tumour necrosis factor: clinical relevance. | Cancer Surv | The anticancer effect of tumour necrosis factor (TNF) in murine tumours and in vitro has stimulated great enthusiasm for investigating its possible therapeutic role in humans. Results have now indicated that 400-800 micrograms ng/m2 of TNF may be given to patients and further dose increases are limited by hypotension and hepatic damage. At this dose, no consistent anticancer effects have yet been seen and measurement of TNF serum concentrations suggests that these effects are less than those required to induce regression of mouse tumours. TNF as a single agent is unlikely to have a major role in the treatment of cancer in humans and further studies will explore combination with other agents. During the investigation of the clinical role of TNF, observations have clarified its biological role as a mediator of inflammation and shock, cachexia and organ dysfunction. |
| 1989 | Altered control of carbohydrate metabolism in endotoxemia. | Prog Clin Biol Res | Based on our data, we envisage the following sequence of events to occur after the administration of a moderately severe dose of endotoxin: Sympathetic stimulation due to hypotension, and possibly other factors, increases plasma concentration of catecholamines. Increased hepatic phosphorylase a activity depletes existing glycogen stores and causes transient hyperglycemia. Lactate release from skeletal muscle is also enhanced, due to the more sustained activation of muscle phosphorylase a and increased uptake of plasma glucose. Stimulation of the immunologically active tissues by endotoxin with the participation of mononuclear phagocytes and TNF results in elevated glycolysis in these tissues as well, thus further enhancing the hyperlactacidemia. The increased precursor concentration and their delivery to the liver stimulate gluconeogenesis, in spite of endotoxin-induced suppression of PEPCK activity. Thus, an elevated precursor supply accelerates gluconeogenesis which is primarily responsible for the increased glucose Ra when hepatic glycogen stores are depleted. It appears that both an increase in blood lactate and catecholamines are important in maintaining the increased gluconeogenesis. This is illustrated schematically in Fig. 4. We postulate that in the fasted nutritionally nonsupported rat, endotoxin enhances glucose utilization in immunologically active tissues as well as in muscle. The presence of catecholamines and the glycolytically produced lactate stimulates gluconeogenesis. These events support the mounting of an effective immune response and aid the body to maintain the immune response by conserving glucose carbon. |
| 1989 | A phase I trial of recombinant tumor necrosis factor (rTNF) administered by continuous intravenous infusion in patients with disseminated malignancy. | Biotherapy | rTNF was administered to 28 patients with advanced metastatic cancers by continuous intravenous infusion for 5 consecutive days every 2 weeks. The dose levels were 30, 40, 70, 110, 180 and 290 micrograms/M2/day. Groups of 3 patients were started at each successive dose level and then on subsequent courses treated with the next dose level through 4 escalations as tolerated. Tumor types were: colon cancer 14; adenocarcinoma of unknown primary, 2; renal cancer, 2; leiomyosarcoma, 2; lung cancer, 1; prostate cancer, 1; thymona, 1; bladder cancer; 1; parotid, 1; Kaposi's sarcoma 2; ovarian 1. Toxicities included fever and chills (usually within the first 8 hours of infusion), fatigue, headache, decreased performance status, hypotension and CNS. All patients experienced leukopenia and thrombocytopenia within 24 hours or less after start of infusion with return of baseline by 72 hours after rTNF was stopped. The fall in these counts averaged 50% and was not dose related. No major changes in liver or renal function, coagulation or blood lipids were seen. Major dose limiting toxicities were fatigue, confusion, thrombocytopenia, seizures, hypotension and decreased performance status. NK cell activity measured against K562 target cells was augmented from about 30% target cell lysis to about 70% target cell lysis over the first 7 days of treatment. Two patients, both with metastatic colon cancer showed transient, objective tumor regression which did not qualify as a partial response. One patient with ovarian cancer had a stable partial response but progressed after 13 courses of treatment. Continuous infusion of TNF can be safely administered to patients with a maximum tolerated dose of only between 30 and 40 micrograms/M2/day.(ABSTRACT TRUNCATED AT 250 WORDS) |
| 1989 | Interleukin-1 induces a shock-like state in rabbits: synergism with tumor necrosis factor and the effect of cyclooxygenase inhibition. | Prog Clin Biol Res | In addition to activating T and B lymphocytes, interleukin-1 (IL-1) induces several hematologic and metabolic changes typical of host responses to infection and injury. We now report a new biological property, namely, the induction of hypotension. Rabbits given a single intravenous injection of recombinant human IL-1-beta (5 micrograms/kg) rapidly developed decreased systemic arterial pressure with the lowest levels after 50-60 min. Associated with the hypotension, systemic vascular resistance and central venous pressure fell while cardiac output and heart rate increased. These responses were prevented by intravenous ibuprofen given 15 minutes prior to the IL-1. A bolus injection of IL-1 plus a 2 hour infusion sustained the hypotension and was associated with leukopenia and thrombocytopenia. Ibuprofen given at the mid-point of the infusion reversed the changes in all hemodynamic parameters. Tumor necrosis factor (TNF) induced a more profound shock-like state in rabbits. When the dose of IL-1 or TNF was reduced to 1 microgram/kg, no hemodynamic changes were observed; however, the combination of these low doses of both cytokines resulted in a profound shock-like state. Ibuprofen prevented the hemodynamic, leukocyte and platelet changes induced by the low-dose cytokine combination. These results demonstrate that IL-1, like TNF, possesses the ability to induce hemodynamic and hematological changes typical of septic shock, that the combination of IL-1 and TNF is more potent than either agent alone, and that cyclooxygenase products are involved in IL-1/TNF-mediated shock. |
| 1988 | Tumor necrosis factor and the acute metabolic response to tissue injury in man. | J Clin Invest | Tumor necrosis factor (cachectin), a protein produced by monocytes and macrophages, has been implicated as an important mediator of the lethal effects of endotoxic shock and the cachexia of chronic infection. Recombinant human tumor necrosis factor alpha (rTNF) was given intravenously to patients as part of an antineoplastic trial. Fever, tachycardia, and at higher doses, hypotension occurred after a single injection of rTNF. Metabolic effects after rTNF administration were dose related and included enhanced energy expenditure with elevated CO2 production, increased whole body protein metabolism and peripheral amino acid efflux from the forearm, and decreased total arterial amino acid levels associated with a significant increase in plasma cortisol. Elevated serum triglycerides, as well as increased glycerol and free fatty acid turnover were seen, suggesting increased whole body lipolysis and fat utilization after rTNF. These findings indicate that administration of TNF in man reproduces many of the acute physiologic and metabolic responses to tissue injury, including energy substrate mobilization. |
| 1988 | Recombinant human tumor necrosis factor administered as a 24-hour intravenous infusion. A phase I and pharmacologic study. | J Natl Cancer Inst | Recombinant human tumor necrosis factor (rH-TNF) is a cytokine with direct antitumor properties. In a phase I trial we continuously infused rH-TNF for 24 hours. We gave a total of 115 courses of therapy to 50 patients. Doses ranged from 4.5 to 645 micrograms of rH-TNF/m2. Systemic toxicity, including fever, chills, fatigue, and hypotension, increased with the dose of rH-TNF administered. Doses greater than 454 micrograms/m2 frequently caused severe lethargy and fatigue, which precluded hospital discharge of the patient at the completion of therapy. The dose-limiting toxicity was hypotension, and five patients treated at the two highest dose levels required dopamine treatment. Other organ-specific toxicity was modest and spontaneously resolved after 48 hours. The 24-hour infusions of rH-TNF were associated with significant decreases in serum cholesterol and high-density lipoprotein levels. Pharmacokinetic studies using an enzyme-linked immunosorbent assay demonstrated peak plasma rH-TNF levels of 90-900 pg/mL. Despite continuous infusion of rH-TNF, no steady-state level was achieved. The recommended phase II dose for rH-TNF as a 24-hour continuous infusion is 545 micrograms/m2. |
| 1988 | Interleukin-1 and tumour necrosis factor cause hypotension in the conscious rabbit. | Clin Sci (Lond) | 1. The cardiovascular effects of intravenous injections of interleukin-1 (IL-1) and tumour necrosis factor (TNF) have been investigated in the conscious rabbit. They have been compared with the effects of bacterial lipopolysaccharide (LPS) because both IL-1 and TNF are released from macrophages by LPS. 2. IL-1, TNF and Escherichia coli J5-LPS all caused hypotension when given intravenously in a dose with low mortality. The time course of the hypotension caused by IL-1 and LPS was similar, although the maximal fall in mean blood pressure occurred earlier after IL-1. TNF produced a more sustained fall in blood pressure. Hypotension was not accompanied by a compensatory tachycardia after any of the test substances. Hypotension was associated with a fever after TNF, hypothermia after LPS and no significant change in temperature after IL-1. 3. The packed cell volume did not change during hypotension in any of the study groups, implying that the hypotension was not due to fluid loss resulting from increased capillary permeability. 4. IL-1 and TNF are candidates for the role of effectors of LPS-induced hypotension. |
| 1988 | Participation of tumor necrosis factor in the mediation of gram negative bacterial lipopolysaccharide-induced injury in rabbits. | J Clin Invest | Macrophages are induced by LPS to release a number of products that determine the host response during gram negative sepsis. To examine the role of one such substance, tumor necrosis factor (TNF), in mediating LPS-induced injury, we employed a rabbit model of endotoxic shock to (a) determine the kinetics and extent of release of TNF into plasma after injection of LPS, and (b) to evaluate the protective effect of in vivo neutralization of LPS-induced TNF by prior infusion of anti-TNF antibody. TNF was maximally induced 45-100 min after injection of 10 micrograms i.v. parent Salmonella minnesota Re595 LPS or 250 micrograms Re595 LPS-HDL complexes. Maximal induction of TNF by LPS was associated with development of hypotension, focal hepatic necrosis, intravascular fibrin deposition and lethality. Based on (a) the peak levels of TNF observed in serum, 2.5 X 10(3) U/ml, (b) the specific activity of purified rabbit macrophage-derived TNF, 1 X 10(8) U/mg, and (c) the biphasic disappearance of intravenously injected purified TNF (t1/2 = 0.5 min, 11 min) we constructed a kinetic model showing that at least 130 micrograms of TNF (1.3 X 10(7) U) was released into plasma 30-200 min postinjection of LPS. Prior infusion of anti-TNF antibody (30-45 min before LPS injection) resulted in neutralization of the LPS-induced serum TNF activity and provided significant protection from the development of hypotension, fibrin deposition, and lethality. Thus, these results provide further evidence that TNF plays a central role mediating the pathophysiologic changes that occur during gram negative endotoxic shock. |
| 1988 | Interleukin 1 induces a shock-like state in rabbits. Synergism with tumor necrosis factor and the effect of cyclooxygenase inhibition. | J Clin Invest | In addition to activating T and B lymphocytes, interleukin 1 (IL-1) induces several hematologic and metabolic changes typical of host responses to infection and injury. We now report a new biological property, namely, the induction of hypotension. Rabbits given a single intravenous injection of recombinant human IL-1-beta (5 micrograms/kg) rapidly developed decreased systemic arterial pressure, which reached the lowest levels after 50-60 min and slowly returned to pre-IL-1 values after 3 h. Associated with the hypotension, systemic vascular resistance and central venous pressure fell, while cardiac output and heart rate increased. These responses were prevented by ibuprofen given 15 min before the IL-1. A bolus injection of IL-1 followed by a 2-h infusion sustained the hypotension and was associated with leukopenia and thrombocytopenia. Ibuprofen given at the mid-point of the infusion reversed the changes in all hemodynamic parameters, but had no effect on the leukopenia or thrombocytopenia. Tumor necrosis factor (TNF) also induced a shock-like state in rabbits. When the dose of IL-1 or TNF was reduced to 1 microgram/kg, no hemodynamic changes were observed; however, the combination of these low doses of both cytokines resulted in a profound shock-like state including histological evidence of severe pulmonary edema and hemorrhage. Pretreatment with ibuprofen prevented the hemodynamic, leukocyte, and platelet changes induced by the low-dose cytokine combination, and ameliorated the pulmonary tissue damage. These results demonstrate that IL-1, like TNF, possesses the ability to induce hemodynamic and hematological changes typical of septic shock, and that the combination of IL-1 and TNF is more potent than either agent alone. These effects seem to require cyclooxygenase products, and suggest that intravenous cyclooxygenase inhibitors may be of therapeutic value in patients with IL-1/TNF-mediated shock. |
| 1988 | Cachectin: a hormone that triggers acute shock and chronic cachexia. | J Infect Dis | Septic shock and invasive infection are diseases caused by humoral mediators of both exogenous and endogenous origin. The search for and identification of these factors has led to the discovery and molecular cloning of cachectin. This pyrogenic cytokine is identical to tumor necrosis factor (TNF) and, when released into the circulation, causes profound shock and multiple organ injury. Cachectin antibodies protect against the lethal effects of mice given endotoxin and baboons given E. coli, a result suggesting that this mediator is both necessary and sufficient to provoke septic shock. Cachectin is produced in humans after endotoxin infusion; the infusion of small doses of TNF is associated with fever, rigors, headache, and hypotension. Septicemic patients also produce cachectin, and during meningococcal infection, patients with the highest serum levels of cachectin die. Chronic cachectin production causes a potentially lethal syndrome of cachexia, anemia, and protein and lipid wasting. Future investigation is being directed toward the development of cachectin antibodies for use in treating the humorally mediated systemic complications of infectious disease. |
| 1988 | Recombinant human tumor necrosis factor administered as a five-day continuous infusion in cancer patients: phase I toxicity and effects on lipid metabolism. | J Clin Oncol | Recombinant human tumor necrosis factor (rH-TNF) is a cytotoxic monokine with pleiotropic effects. A phase I trial of rH-TNF was initiated using a five-day continuous intravenous (IV) infusion repeated every 28 days. Thirty-eight courses of therapy were administered to 19 patients. The starting dose was 5 X 10(4) U/m2/d, with escalations to 1.0 X 10(5), 2.0 X 10(5), 2.4 X 10(5), and 3.0 X 10(5) U/m2/d. Systemic side effects, including fever, chills, hypotension, fatigue, anorexia, and headaches, were mild and self-limiting. At the maximum tolerated dose of 3.0 X 10(5) U/m2/d, dose-limiting hematologic toxicity was manifested by transient thrombocytopenia and leukopenia. Elevated bilirubin levels were also seen at the higher dose levels. Lipoprotein analysis demonstrated that the five-day treatment with rH-TNF was associated with decreases in high-density lipoproteins, as well as increases in triglycerides and very-low-density lipoproteins. Pharmacokinetic studies using an enzyme-linked immunosorbent assay (ELISA) test indicated plasma rH-TNF levels less than 0.2 U/mL. The recommended phase II dose of rH-TNF administered as a five-day continuous infusion is 2.4 X 10(5) U/m2/d. |
| 1988 | Phase I study of recombinant human tumor necrosis factor (rHu-TNF:PT-050). | Cancer Detect Prev | A phase I study of recombinant human tumor necrosis factor (rHu-TNF:PT-050) given by intravenous infusion over 30 min or by intratumoral administration was performed in 53 patients with various types of malignant tumors. The dose of rHu-TNF was started with 0.1 x 10(6) U/body for both intravenous infusion and intratumoral administration and increased to 5 x 10(6) U/body for intravenous infusion and 2 x 10(6) U/body for intratumoral administration. The side effects of rHu-TNF given by intravenous infusion included fever, shaking chills, hypotension, general malaise, nausea, and vomiting, and clinical laboratory tests showed elevations of GOT, GPT, and ALP, etc. Among these, only hypotension was dose-related and was considered to be a dose-limiting factor. The maximum tolerable dose estimated was 1 x 10(6) U/body. The plasma concentration of rHu-TNF after completion of a 30-min infusion was dose-dependent, and the elimination half-life was 0.5-2.4 hr. When the rHu-TNF was administered intratumorally, the frequency of side effects was low compared with intravenous infusion. |
| Anti-cachectin/TNF monoclonal antibodies prevent septic shock during lethal bacteraemia. | Nature | Bacterial infection of the mammalian bloodstream can lead to overwhelming sepsis, a potentially fatal syndrome of irreversible cardiovascular collapse (shock) and critical organ failure. Cachectin, also known as tumour necrosis factor, is a macrophage-derived peptide hormone released in response to bacterial lipopolysaccharide, and it has been implicated as a principal mediator of endotoxic shock, although its function in bacterial sepsis is not known. Anaesthetized baboons were passively immunized against endogenous cachectin and subsequently infused with an LD100 dose of live Escherichia coli. Control animals (not immunized against cachectin) developed hypotension followed by lethal renal and pulmonary failure. Neutralizing monoclonal anti-cachectin antibody fragments (F(ab')2) administered to baboons only one hour before bacterial challenge protected against shock, but did not prevent critical organ failure. Complete protection against shock, vital organ dysfunction, persistent stress hormone release and death was conferred by administration of antibodies 2 h before bacterial infusion. These results indicate that cachectin is a mediator of fatal bacteraemic shock, and suggest that antibodies against cachectin offer a potential therapy of life-threatening infection. |
| 1987 | Tumour necrosis factor in man: clinical and biological observations. | Br J Cancer | Eighteen patients with advanced cancer have been treated intravenously with human recombinant tumour necrosis factor (rhTNF). The drug produced febrile reactions at all doses although these were preventable by steroids and indomethacin. Doses at or above 9 x 10(5) units (400 micrograms)m-2 were associated with hypotension, abnormal liver enzymes, leucopenia and mild renal impairment in a substantial proportion of patients. RhTNF was cleared from plasma with a half life of approximately 20 minutes but non-linear pharmacokinetics lymphoma, improvements in their tumours were recorded. RhTNF was noted to produce rapid increases in serum C-reactive protein concentrations. Endogenous TNF levels were not found to be elevated in 72 cancer patients. TNF deserves further therapeutic evaluation and these observations support its biological importance as an endogenous pyrogen, mediator of acute phase protein responses, and a mediator of endotoxic shock. |
| 1987 | The biology of interleukin 1 and comparison to tumor necrosis factor. | Immunol Lett | Interleukin 1 (IL-1) is a major product of the stimulated monocyte and is responsible for diverse biological effects. The systemic effects of IL-1 include fever, increased circulating neutrophils, hepatic acute phase proteins, slow wave sleep, elevated insulin levels and hypotension. In vitro, IL-1 induces increased synthesis of a number of lymphokines (IL-2, IL-3, IL-4 and IL-6), a variety of colony stimulating factors, and endothelial factors leading to clot formation and vascular congestion. IL-1 also induces histamine release and granule release from basophils, eosinophils and neutrophils. IL-1 dramatically increases arachidonic acid metabolites in a variety of cells; increased PGE2 synthesis accounts for its inflammatory properties. Tumor necrosis factor shares with IL-1 many of the systemic and local effects of IL-1; these include fever, acute phase protein synthesis and sleep. Some of the in vitro effects of IL-1 are not shared with TNF, but the combination of TNF with IL-1 often enhances the response several-fold. A dramatic synergism between IL-1 and TNF occurs on islets of Langerhans. In vivo, these two cytokines induce shock and pulmonary hemorrhage when given together but at doses at which neither cytokine is effective alone. Profound leukopenia and thromocytopenia are present. Since both cytokines are produced in large amounts following appropriate stimulation, the end result for the host is the combined effect of both cytokines. |
| 1987 | Phase I clinical trial of recombinant human tumor necrosis factor. | Cancer Chemother Pharmacol | A phase I and pharmacokinetic study of recombinant tumor necrosis factor (rH-TNF Asahi) was carried out in 29 patients, who received a total of 72 courses with doses ranging from 1 to 48 X 10(4) units/m2. Drug was given as 1-h i.v. infusions. Acute toxicities, taking the form of fever, chills, tachycardia, hypertension, peripheral cyanosis, nausea and vomiting, headache, chest tightness, low back pain, diarrhea and shortness of breath were seen, but were not dose-limiting or dose-related. Some early rise in SGOT, without any change in serum bilirubin, was noted at the highest doses. Eosinophilia, monocytosis, mild hypocalcemia and an increase in fibrin degradation products were seen in a few patients. The dose-limiting toxicity was hypotension, which occurred after the end of the drug infusion and was seen in all 5 patients treated at the highest dose. There was no mortality or long-term morbidity. There were no responses. Pharmacokinetic studies indicated a rapid plasma clearance and a short plasma half-life, generally less than 0.5 h. |
| 1987 | Clinical studies with tumour necrosis factor. | Ciba Found Symp | The mechanism of tumour necrosis factor (TNF) cytotoxicity remains unknown. The in vivo antitumour effects of TNF may be related to direct cytotoxicity, immunomodulatory effects or endothelial effects on tumour vasculature. Phase I and early Phase II clinical trials of human recombinant TNF are under way in Japan, the USA, the UK and Germany. The maximum Phase II dose for TNF has not been established. The clinical toxicity of TNF is generally similar to that of other biological agents. Systemic toxicity, including fever, chills, anorexia and nausea, has been seen in most patients treated with TNF and has not been clearly related to dose. Other toxicities have included liver function abnormalities, hypotension, transient neurological changes and haematological abnormalities. Few clinical responses have been reported but organized Phase II testing remains to be completed. Combination trials with interferons have recently been initiated. Phase II efficacy studies of TNF as a single agent and in combination are needed for an assessment of the value of this agent in cancer therapy. |
| 1987 | Phase I study of recombinant human tumor necrosis factor. | Cancer Chemother Pharmacol | A phase I clinical and pharmacokinetic study of recombinant human tumor necrosis factor (rH-TNF) was conducted in a single dose schedule in 33 patients with advanced cancer. rH-TNF was given by i.v. infusion over 30 min with a starting dose of 1 x 10(5) units/m2. The dose was escalated up to 16 x 10(5) units/m2 according to the modified Fibonacci scheme. Toxic effects were similar but not identical to those reported with interferons and interleukin-2, and included fever, rigors, nausea and vomiting and anorexia in a non-dose-dependent manner, and hypotension, leukocytosis, thrombocytopenia and transient elevation of transaminases (SGOT and SGPT) in an approximately dose-dependent manner. DIC syndrome was observed in one patient who had received 16 x 10(5) units/m2. The dose-limiting toxicities were hypotension, thrombocytopenia and hepatotoxicity, and the maximum tolerated dose in a single i.v. infusion of rH-TNF appeared to be 12 x 10(5) units/m2 when thrombocytopenia and elevation of SGOT and SGPT were taken as the dose-limiting toxicities. However, if hypotension was included, the maximum safely tolerated dose appeared to be 5 x 10(5) units/m2. |
| 1987 | Structure-function relationship of tumour necrosis factor and its mechanism of action. | Ciba Found Symp | We have cloned the cDNAs of both human and mouse TNF and expressed them to high efficiency in Escherichia coli. Many transformed cell lines are sensitive to the cytotoxic action of TNF, especially in the presence of gamma-interferon, whereas normal cells either are unaffected or respond mitogenically. A number of human-mouse chimeric TNF genes have been constructed and expressed. All show biological activity but none of the chimeric proteins is neutralized by monoclonal antibodies to TNF. TNF has potent antitumour activity in nude mice carrying human xenografts or in mice bearing syngeneic tumours. In some systems direct effects can be demonstrated (in combination with species-specific gamma-interferon) but in others TNF acts indirectly. Combination of TNF with cytostatic drugs can also be effective in curing in vivo. The major limitation of the use of TNF is its toxicity. On many cell types TNF has an action similar to interleukin 1 (IL-1). At least some of the secondary, intracellular events may be identical for the two effectors. A possible mechanism of action of TNF is the release and metabolism of polyunsaturated fatty acids, which would explain the synthesis of prostaglandins and leukotrienes by many cell types after TNF treatment. The activation of the phospholipase can be blocked by corticoids. Some protease inhibitors protect cells from TNF-induced cytotoxicity but the target of these inhibitors has not been identified. Several genes are switched on by TNF (and by IL-1), including the gene for the 26 kDa protein recently identified as B cell stimulation factor 2. Events preceding death in rats include hypothermia, hypotension, acidosis and hypoglycaemia. All these effects can be largely eliminated by indomethacin pretreatment, with a resulting improvement in survival. As indomethacin does not inhibit the cytotoxic action of TNF on malignant cells it may form the basis for improved treatment protocols. |
| 1986 | [A phase I study of recombinant human tumor necrosis factor (rHu-TNF: PT-050). The PT-050 Study Group]. | Gan To Kagaku Ryoho | A Phase I study of rHu-TNF (PT-050) was conducted in patients with various malignant tumors refractory to conventional therapy. rHu-TNF was administered by 30-min intravenous (i.v.) infusion or intratumor (i.t.) injection. The starting dose of 1 X 10(5) U/body was increased to 5 X 10(6) U/body in the i.v. group and to 2 X 10(6) U/body in the i.t. group. rHu-TNF was evaluated in 41 patients among the enrolled 43 patients of the i.v. group, and in 9 out of 10 in the i.t. group. In the i.v. group, fever (68.3%), chills (75.6%), hypotension (46.3%), general fatigue (34.1%), nausea/vomiting (22.0%/22.0%), pain in the extremities (17.1%), etc. were observed as adverse reactions (ADRs), and elevation of GOT/GPT (46.3%/43.9%), elevation of ALP(26.8%)and decrease in platelets (12.2%), etc. were observed as abnormal laboratory findings. Among these, hypotension was recognized as the dose-limiting factor and the maximum tolerated dose was considered to be 1 X 10(6) U/body. Plasma levels of rHu-TNF after 30-min i.v. administration were dose-related, and decreased with half-lives of 0.5-2.4 hours. In the i.t. group, ADRs occurred with a lower incidence than in the i.v. group except for fever, chills and general fatigue. Plasma levels after i.t. administration were all within the assay limit. Evident tissue necrosis was observed in the region where rHu-TNF was administered in the i.t. group. |