Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.2 (alanine aminotransferase)
 26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the era of antiretroviral therapy, liver disease has emerged as an important cause of morbidity and mortality in HIV/hepatitis C virus (HCV) coinfected patients. It is believed that HCV is a non-cytopathic virus and that T-cell-mediated events (including the production of pro-inflammatory cytokines) have an important role in promoting both liver damage and viral clearance. Whether HIV coinfection or antiretroviral therapies influence such events is still unclear. In the current study, we compared the expression of NKp46 (a natural killer cell marker), CD3 (a T-cell marker), interferon-gamma (IFN-gamma), tumour-necrosis factor-alpha (TNF-alpha; pro-inflammatory cytokines) and interleukin-10 (IL-10; an anti-inflammatory cytokine) mRNA in the liver of naive HIV/HCV-coinfected patients (group one, n=14), coinfected patients treated with antiretroviral therapy (group two, n=23) and naive HCV mono-infected patients (group three, n=24). All three groups had comparable HCV viremia, with coinfected patients showing similar and relatively high CD4+ T-cell counts and significantly different HIV vireamia. Interestingly, when compared to groups two and three, group one showed significantly higher intrahepatic mRNA levels for CD3, IFN-gamma and TNF-alpha, whereas the expression of NKp46 and IL-10 were comparable in all three groups. Further, higher histopathological grading scores within each group were independently associated with higher mRNA contents for CD3 and IFN-gamma and higher serum alanine aminotransferase levels at the time of liver biopsy. Together, these results suggest that HIV infection may exacerbate the immune-mediated inflammatory response in the liver of patients chronically infected with HCV and antiretroviral therapy may prevent this effect.
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PMID:Naive HIV/HCV-coinfected patients have higher intrahepatic pro-inflammatory cytokines than coinfected patients treated with antiretroviral therapy. 1675 56

Neutrophils are recruited into the liver after acetaminophen (AAP) overdose but the pathophysiological relevance of this acute inflammatory response remains unclear. To address this question, we compared the time course of liver injury, hepatic neutrophil accumulation and inflammatory gene mRNA expression for up to 24 h after treatment with 300 mg/kg AAP in C3Heb/FeJ and C57BL/6 mice. Although there was no relevant difference in liver injury (assessed by the increase of plasma alanine aminotransferase activities and the areas of necrosis), the number of neutrophils and the expression of several pro-inflammatory genes (e.g., tumor necrosis factor-alpha, interleukin-1beta and macrophage inflammatory protein-2) was higher in C3Heb/FeJ than in C57BL/6 mice. In contrast, the expression of the anti-inflammatory genes interleukin-10 and heme oxygenase-1 was higher in C57BL/6 mice. Despite substantial hepatic neutrophil accumulation, none of the liver sections from both strains stained positive for hypochlorite-modified proteins, a specific marker for a neutrophil-induced oxidant stress. In addition, treatment with the NADPH oxidase inhibitors diphenyleneiodonium chloride or apocynin or the anti-neutrophil antibody Gr-1 did not protect against AAP hepatotoxicity. Furthermore, although intercellular adhesion molecule-1 (ICAM-1) was previously shown to be important for neutrophil extravasation and tissue injury in several models, ICAM-1-deficient mice were not protected against AAP-mediated liver injury. Together, these data do not support the hypothesis that neutrophils aggravate liver injury induced by AAP overdose.
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PMID:Pathophysiological role of the acute inflammatory response during acetaminophen hepatotoxicity. 1678 46

N-acetylcysteine (NAC) is an antioxidant and cytoprotective agent with scavenging action against reactive oxygen species and inhibitory effects on pro-inflammatory cytokines. In a previous study, we found that pretreatment with NAC attenuated organ dysfunction and damage, reduced the production of free radicals, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) following endotoxemia elicited by administration of lipopolysaccharide (LPS). In the present study, we tested the effects of post-treatment with NAC on the sepsis-induced change. Post-treatment imitates clinical therapeutic regimen with administration of drug after endotoxemia. Endotoxin shock was induced by intravenous injection of Klebsiella pneumoniae LPS (10 mg/kg) in conscious rats. Mean arterial pressure (MAP) and heart rate (HR) were continuously monitored for 48 h after LPS administration. NAC was given 20 min after LPS. Measurements of biochemical substances were taken to reflect organ functions. Biochemical factors included blood urea nitrogen (BUN), creatinine (Cre), lactate dehydrogenase (LDH), creatine phosphokinase (CPK), aspartate transferase (GOT), alanine transferase (GPT), TNF-alpha, interleukin-6 (IL-6), and interleukin-10 (IL-10). LPS significantly increased blood BUN, Cre, LDH, CPK, GOT, GPT, TNF-alpha, IL-6, IL-10 levels and HR, and decreased MAP. Post-treatment with NAC diminished the decrease in MAP, increased the HR, and decreased the markers of organ injury (BUN, Cre, LDH, CPK, GOT, GPT) and inflammatory biomarkers (TNF-alpha, IL-6, IL-10) after LPS. We conclude that post-treatment with NAC suppresses the release of plasma TNF-alpha, IL-6, and IL-10 in endotoxin shock, and decreases the markers of organ injury. These beneficial effects protect against LPS-induced kidney, heart and liver damage in conscious rats. The beneficial effects may suggest a potential chemopreventive effect of this compound after sepsis.
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PMID:Post-treatment with N-acetylcysteine ameliorates endotoxin shock-induced organ damage in conscious rats. 1686 Mar 47

Chronicity in hepatitis B virus (HBV) infection is maintained by increased type 2 T-helper cell response, possibly because of increased interleukin-10 (IL-10) productions. B7-H1 can negatively regulate T-cell responses via its receptor, programmed death 1. Ligation of B7-H1 to T-cells can result in the preferential secretion of IL-10. In this study, we investigated whether there was an upregulated expression of B7-H1 in peripheral blood mononuclear cells in patients chronically infected by HBV and further explored the correlation between B7-H1 expression and serum interleukin 2, interferon-gamma, IL-10, HBeAg, alanine aminotransferase (ALT) levels and viral load. Fifty-five patients with chronic HBV infection and 20 healthy controls (HCs) were enrolled in the present study. The results showed that in patients with chronic hepatitis B CD14+ monocytes but not CD3+ and CD19+ cells had a significantly increased expression of B7-H1 compared with HCs, which positively correlates with serum IL-10 levels and the presence of HBeAg and negatively correlates with serum ALT levels. In conclusion, chronic HBV patients harbour an increased B7-H1 expression in CD14+ monocytes compared with controls, which may be responsible for the increased serum IL-10 levels. This might be an important way by which HBV evades an adequate immune response, leading to viral persistence and disease chronicity.
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PMID:B7-H1 expression is upregulated in peripheral blood CD14+ monocytes of patients with chronic hepatitis B virus infection, which correlates with higher serum IL-10 levels. 1705 71

To elucidate the roles of enteric bacteria and immunological interactions among liver, spleen and intestine in the pathogenesis of liver injury during obstructive jaundice, we studied the effects of antibiotics and splenectomy on bile-duct-ligated C57BL mice. When animals were subjected to bile-duct-ligation (BDL), plasma levels of bilirubin, alanine aminotransferase and aspartate aminotransferase increased markedly. However, the increases in plasma transaminases were significantly lower in splenectomized or antibiotics-treated groups than in the control BDL group. Histological examination revealed that liver injury was also low in the two groups. BDL markedly increased plasma level of interferon-gamma (IFN-gamma) and the expression of inducible nitric oxide synthase (iNOS) in liver and spleen. These changes were suppressed either by splenectomy or administration of antibiotics. Kinetic analysis revealed that BDL-induced liver injury and the increase of interleukin-10 (IL-10) and INF-gamma were lower in iNOS(-/-) than in wild type animals. BDL markedly increased the expression of IgA in colonic mucosa. These observations suggest that enteric bacteria, nitric oxide and cytokines including IFN-gamma and IL-10 derived from spleen and intestines form a critical network that determines the extent of liver injury during obstructive jaundice.
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PMID:Mechanism of Liver Injury during Obstructive Jaundice: Role of Nitric Oxide, Splenic Cytokines, and Intestinal Flora. 1839 95

The involvement of oxidative and nitrosative mediators in liver injury caused by heat stress remains unclear. This study aimed to elucidate the role of endothelial nitric oxide synthase (eNOS), and inducible NOS (iNOS)-derived NO and nitrotyrosine in the whole-body hyperthermia (WBH)-induced liver injury. Rats were anesthetized with intraperitoneal pentobarbital, and were exposed to a heating lamp for 60 min to raise the core temperature to 42.5 degrees C. The rats were maintained at the hyperthermic state for an additional 50 min. Blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, lactic dehydrogenase, creatine phosphokinase, amylase, lipase, nitrate/nitrite, methyl guanidine, and proinflammatory cytokines (tumor necrosis factoralpha, interleukin-1beta and interleukin-10) were measured before and 14 h after hyperthermia. Immunohistochemical staining was employed to detect the eNOS, iNOS and nitrotyrosine levels. Western blotting was used to examine the expression of heatshock protein 70 (HSP 70). Histopathological examination of the liver tissue was performed. WBH caused liver injury accompanied with significant increases in biochemical factors, nitrate/nitrite, methyl guanidine, and proinflammatory cytokines. In addition, WBH enhanced the eNOS, iNOS, nitrotyrosine and HSP 70 levels. WBH caused hepatic injury. The pathogenetic mechanism is likely mediated through the NOS-derived NO, free radical, proinflammatory cytokines and nitrotyrosine. The enhanced expression of HSP 70 may play a protective role.
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PMID:Oxidative and nitrosative mediators in hepatic injury caused by whole body hyperthermia in rats. 1866 11

The freshwater clam is a widely-consumed shellfish and is used as a remedy for chronic hepatitis in Asia. However, its contribution to acute liver injury (ALI) remains unclear. The aim of this study is to assess the protective effects of freshwater clam extract (CE) in ALI induced by hemorrhage in rats. Rats were randomly divided into 5 groups, (1) blood loss (BL) 40%, (2) CE 150 mg/kg plus BL 40%, (3) CE 75 mg/kg plus BL 40%, (4) CE 150 mg/kg, and (5) CE 75 mg/kg groups. CE was given by femoral vein catheter in Groups 2 to 5. Initial hemorrhage was induced by withdrawing blood (loss 40% of total blood volume) from a femoral arterial catheter after CE administration in Groups 2 and 3. The levels of blood tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were measured at several time points during the experimental period. Rats were sacrificed after 48 hours, and the liver was harvested for hematoxylin and eosin (HE) stain to show liver tissue injury. The results indicated that hemorrhage significantly decreased mean arterial pressure (MAP), increased blood AST, ALT and LDH levels and induced liver injury. Pre-treatment with the CE increased MAP and IL-10 levels and decreased AST, ALT, LDH and TNF-alpha levels after hemorrhage. The HE stains showed diminished organ injury in the CE groups. In conclusion, freshwater clam extract is a potential immunomodulating agent and ameliorates acute liver injury.
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PMID:Freshwater clam extract ameliorates acute liver injury induced by hemorrhage in rats. 1905 40

We have recently observed that oral administration of D-glucose saves animals from lipopolysaccharide (LPS)-induced death. This effect is the likely consequence of glucose-induced activation of the sodium-dependent glucose transporter-1. In this study, we investigated possible hepatoprotective effects of glucose-induced, sodium-dependent, glucose transporter-1 activation. We show that oral administration of D-glucose, but not of either D-fructose or sucrose, prevents LPS-induced liver injury, as well as liver injury and death induced by an overdose of acetaminophen. In both of these models, physiological liver morphology is maintained and organ protection is confirmed by unchanged levels of the circulating markers of hepatotoxicity, such as alanine transaminase or lactate dehydrogenase. In addition, D-glucose was found to protect the liver from alpha-amanitin-induced liver injury. In this case, in contrast to the previously described models, a second signal had to be present in addition to glucose to achieve protective efficacy. Toll-like receptor 4 stimulation that was induced by low doses of LPS was identified as such a second signal. Eventually, the protective effect of orally administered glucose on liver injury induced by LPS, overdose of acetaminophen, or alpha-amanitin was shown to be mediated by the anti-inflammatory cytokine interleukin-10. These findings, showing glucose-induced protective effects in several animal models of liver injury, might be relevant in view of possible therapeutic interventions against different forms of acute hepatic injury.
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PMID:Intestinal glucose uptake protects liver from lipopolysaccharide and D-galactosamine, acetaminophen, and alpha-amanitin in mice. 1970 Jul 51

The present study was conducted to assess the effects of whole body cooling on multiorgan dysfunction that occurred during heatstroke in streptozotocin (STZ)-induced diabetic rats. The rats were randomly divided into four groups: [1] the normal control, [2] diabetic control, [3] diabetic heatstroke, and [4] diabetic heatstroke-whole body cooling (WBC). They were exposed to ambient temperature of 43 degrees C for exactly 58 min to induce heatstroke. When the diabetic heatstroke rats underwent heat stress, their survival time values were found to be 11-13 min. Immediately after the onset of heatstroke, resuscitation with body cooling greatly improved survival (221-257 min). Compared with the diabetic (STZ-treated) controls, the diabetic-heatstroke rats displayed higher levels of body temperature, intracranial pressure, serum nitric oxide metabolite, tumor necrosis factor-alpha and dihydroxybenzoic acid, blood urea nitrogen, creatinine, alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. In contrast, the values of mean arterial pressure, cerebral perfusion pressure, and brain levels of local blood flow, and partial pressure of oxygen were all significantly lower during heatstroke. The cerebrovascular, renal, and hepatic dysfunction, the increased levels of nitric oxide metabolites, tumor necrosis factor-alpha, and dihydroxybenzoic acid in the serum during heatstroke were significantly reduced by WBC. Although the serum interleukin-10 maintained at a negligible levels before heat stress, they were significantly elevated by WBC in diabetic-heatstroke rats. The data demonstrate that heatstroke-induced multiorgan dysfunction in streptozotocin-induced diabetic rats can be decreased by WBC.
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PMID:Decrease of heatstroke-induced multiorgan dysfunction by whole body cooling in streptozotocin-induced diabetic rats. 1976 53

In this study, the effects of fucoidan on aspirin-induced ulcers in rats were evaluated: both biochemical and immunological parameters were taken into consideration. The status of stomach tissue glycogen storage and histological changes were also examined. Examination of basic biochemical parameters showed significant (p<0.01) alterations in aspartate (AST) and alanine (ALT) transaminases in ulcer-induced rats. Also, moderate alterations (p<0.05) were observed in the levels of cholesterol and blood urea nitrogen (BUN). Histopathological examination showed neutrophil infiltration and inflammation in oxyntic cells with altered glycogen storage. Analysis of serum cytokines of aspirin-induced rats showed a moderate decrease in interleukin-10 (IL-10) with considerable increase of interleukin-6 (IL-6) and interferon-gamma (INF-gamma) when compared with control. Administration of fucoidan showed considerable (p<0.05) protection against ulceration by inhibiting the acute alterations of AST, ALT, cytokines and stomach glycogen. However, aggravated serum INF-gamma was observed in the fucoidan-pretreated group. These findings suggest that the anti-ulcer property of fucoidan might contribute in protecting the inflammatory cytokine-mediated oxidative damage to gastric mucosa.
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PMID:Effect of fucoidan on aspirin-induced stomach ulceration in rats. 1978 92


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