Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.1 (aspartate aminotransferase)
21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Superoxide dismutase (SOD) activity was evaluated by measuring superoxide scavenging capability with the aid of an electron spin resonance (ESR) spin trapping method in a swine orthotopic liver transplantation (OLT) model. The animals were divided into two groups, depending on the length of the survival periods: the short survival group (n = 8) survived less than 6 days and the long survival group (n = 15) 6 days or longer. SOD activity was significantly lower in the short survival group than in the long survival group after reperfusion (P < 0.01). During the period of cold preservation, a minimal change in SOD activity was noted, regardless of the length of preservation. Serum aspartate aminotransferase (AST) levels after reperfusion and serum lactate dehydrogenase (LDH) levels 1 h after reperfusion were significantly higher in the short survival group than in the long survival group (P < 0.01 and P < 0.05, respectively). The difference in polymorphonuclear leukocytes (PMN) was significantly greater in the short survival group at 1 h after reperfusion (P < 0.01). The authors conclude that superoxide scavenging activities in the graft reflect the magnitude of reperfusion injury, which can be a reliable parameter for the estimation of graft outcome.
...
PMID:Superoxide scavenging activity in experimental liver transplantation. 754 46

Superoxide anion radical (O2-) is one factor related to ischemia/reperfusion injury to the liver. The sites of O2- production and injury have yet to be determined. Superoxide dismutase (SOD), a specific scavenger for O2-, has an inhibitory effect on injury caused by O2-. SOD is of low molecular weight; hence, it has a short half-life in the circulating blood. Mannosylated SOD is taken up in sinusoidal endothelial cells of the liver by receptor-mediated endocytosis. In rats with an occluded inflow against 70% of the liver for 30 min followed by reperfusion there were elevations of serum aspartate aminotransferase and alanine aminotransferase, and lipid peroxide concentrations in liver tissue were significantly inhibited by intravenous administration of mannosylated SOD compared to treatment with normal saline. Electron microscopic examination showed that mannosylated SOD protected against damage to the sinusoidal endothelial cells caused by ischemia/reperfusion and that conventional SOD had no such protective effect. Thus, O2- produced by ischemia/reperfusion apparently damages sinusoidal endothelial cells, and damage to hepatic parenchymal cells is secondary. Mannosylated SOD deserves further study for possible use in surgical resection of the liver and for liver transplantations.
...
PMID:Mannosylated superoxide dismutase inhibits hepatic reperfusion injury in rats. 859 29

Age-associated changes in liver injury and post-necrotic regeneration were studied in rats aged 6 and 30 months in a period of 96 h following a dose of thioacetamide (6.6 mmol/kg body weight). Hepatocellular necrosis was detected in both groups by serum aspartate aminotransferase, but the severity of injury was significantly lower (one fourth, p < 0.001) in the oldest. Differences were observed in hepatocyte FAD monooxygenase activity between 6 and 30 months old rats at 24 h (278 versus 170%, p < 0.001, respectively) and also in GSH/GSSG ratio, in protein thiol groups and in malondialdehyde. Glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase activities rose markedly in both groups, this increase being slightly lower in the oldest. Superoxide dismutase and catalase did not show significant changes between both groups. At the end of the 96 h experimental period the restoration towards normal of GSG/GSSG, protein thiols malondialdehyde and the activities of Cu-Zn superoxide dismutase and catalase were significantly lower in hepatocytes from 30 months old rats. We summarize that the main age-related changes in the sequenced process of liver injury and regeneration occurred to a lesser extent in severity of injury and delayed response in the post-necrotic restoration of liver function, probably due to a lower increase in antioxidant enzyme system.
...
PMID:Aging delays the post-necrotic restoration of liver function. 969 17

During an outbreak of dengue fever in 1996, 66 children between 45 days and 12 years of age with dengue fever and 25 healthy controls were studied for antioxidants and other biochemical abnormalities. As per World Health Organization (WHO) criteria, 14 children were classified as having classical dengue (DEN), 42 with dengue haemorrhagic fever (DHF), and 10 (including three who died) as having dengue shock syndrome (DSS). Superoxide dismutase (SOD), glutathione peroxidase (GPX), and albumin (ALB), the three main antioxidants studied, were found to be abnormal in 96, 94, and 40 per cent of the cases respectively. The levels for aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine phosphokinase (CPK), total protein (TP), total cholesterol (CHO), and triglycerides (TGL) were abnormal in 79, 50, 30, 93, and 67 per cent of the cases respectively. Among the different groups of dengue the abnormalities were more marked in children with DSS than in those with DEN and DHF, especially with respect to ALB, TP, TGL, AST, ALT, and CPK (p < 0.005). This preliminary report of dengue confirms the assumption of free radical generation and alteration in antioxidant status during acute illness. However, to understand their complex interaction in disease progression and therapeutic utility, further studies are required.
...
PMID:Status of antioxidants and other biochemical abnormalities in children with dengue fever. 1019 85

The purpose of our study was to assess the effects of experimental dicroceliosis on the antioxidant defense capability of the liver in hamsters. Studies were carried out at 80 and 120 days after infection with an oral dose of 40 metacercariae of Dicrocoelium dendriticum. The parasitic pathology was ascertained by the presence of fluke eggs in feces, increased serum ALT and AST activities, and histological findings. The concentration of thiobarbituric acid-reactive substances (TBARS) and the ratio of oxidized to reduced glutathione (GSSG/GSH), measured as markers of oxidative stress, were significantly increased [TBARS: +40% and +84% at 80 and 120 days postinfection (p.i.), respectively; GSSG/GSH: +200% and +117%]. Dicroceliosis increased Se-dependent glutathione peroxidase (GPx) activity in both cytosol (+24% and +46%) and mitochondria (+73% and +41%). Superoxide dismutase activity was significantly reduced in cytosol (-19% and -38%) and mitochondria (-20% and -39%). No significant change was found in the activity of Se-independent GPx or catalase. The ratio of glutathione peroxidase/glutathione reductase at 80 and 120 days p.i. was increased by 25% and 63%, respectively. Gamma-glutamyl cysteinyl synthetase activity was increased by 27% and 20%, respectively. Our data indicate that although dicroceliosis courses with activation of antioxidant enzymes and glutathione synthesis, inefficient scavenging of reactive oxygen species takes place, resulting in oxidative liver damage.
...
PMID:Oxidative stress and changes in liver antioxidant enzymes induced by experimental dicroceliosis in hamsters. 1034 40

Increased oxidative stress and impaired antioxidant defense mechanisms are important factors in the pathogenesis and progression of diabetes mellitus and other oxidant-related diseases. This study was designed to determine whether alpha-lipoic acid, which has been shown to have substantial antioxidant properties, when administered (10 mg/kg ip) once daily for 14 days to normal and diabetic female Sprague-Dawley rats would prevent diabetes-induced changes in biomarkers of oxidative stress in liver, kidney and heart. Serum glucose concentrations, aspartate aminotransferase activity, and glycated hemoglobin levels, which were increased in diabetes, were not significantly altered by alpha-lipoic acid treatment. Normal rats treated with a high dose of alpha-lipoic acid (50 mg/kg) survived but diabetic rats on similar treatment died during the course of the experiment. The activity of glutathione peroxidase was increased in livers of normal rats treated with alpha-lipoic acid, but decreased in diabetic rats after alpha-lipoic acid treatment. Hepatic catalase activity was decreased in both normal and diabetic rats after alpha-lipoic acid treatment. Concentrations of reduced glutathione and glutathione disulfide in liver were increased after alpha-lipoic acid treatment of normal rats, but were not altered in diabetics. In kidney, glutathione peroxidase activity was elevated in diabetic rats, and in both normal and diabetic animals after alpha-lipoic acid treatment. Superoxide dismutase activity in heart was decreased in diabetic rats but normalized after treatment with alpha-lipoic acid; other cardiac enzyme activities were not influenced by either diabetes or antioxidant treatment. These results suggest that after 14 days of treatment with an appropriate pharmacological dose, alpha-lipoic acid may reduce oxidative stress in STZ-induced diabetic rats, perhaps by modulating the thiol status of the cells.
...
PMID:Effects of alpha-lipoic acid on biomarkers of oxidative stress in streptozotocin-induced diabetic rats. 1283 33

Sesame oil is regarded as a daily nutritional supplement to increase cell resistance to lipid peroxidation. The aims of this study were to examine the effects of parenteral sesame oil on oxidative stress and hepatic disorder induced by lipopolysaccharide and to determine the defense mechanisms involved in sesame oil-associated anti-oxidative effects in rats. Oxidative stress was induced by lipopolysaccharide (5 mg/kg, intraperitoneally) and assessed by determination of lipid peroxidation. Sesame oil (8 ml/kg, subcutaneously) was given 3 h after lipopolysaccharide, and lipid peroxide levels, hydroxyl radical, superoxide anion, the enzyme activities of superoxide dismutase and catalase as well as the levels of glutathione and nitrite were examined 6 h after lipopolysaccharide. Hepatic function was assessed by determining the activities of serum aspartate aminotransferase and alkaline phosphatase. Sesame oil reduced lipid peroxidation and hydroxyl radical, but failed to affect superoxide anion. Superoxide dismutase and catalase were increased, but glutathione was not affected, and the levels of nitrite were reduced. Further, sesame oil-treated groups showed attenuated hepatic disorder in lipopolysaccharide-treated rats. Thus, parenteral sesame oil can be used to attenuate oxidative stress and relieve hepatic disorder after lipopolysaccharide intoxication in rats.
...
PMID:Parenteral sesame oil attenuates oxidative stress after endotoxin intoxication in rats. 1503 64

This study was planned to determine the protective role of zinc, if any, in attenuating the toxicity induced by nickel sulfate in rat liver. Female Sprague Dawley (SD) rats received either nickel alone in the dose of 800 mg/l in drinking water, zinc alone in the dose of 227 mg/l in drinking water, and nickel plus zinc or drinking water alone for a total duration of eight weeks. The effects of different treatments were studied on various parameters in rat liver which include antioxidant enzymes, levels of nickel and zinc and histoarchitecture at the light microscopic level. Further, the activities of hepatic marker enzymes AST and ALT were also studied in rat serum. Nickel treatment to the normal control animals, resulted in a significant increase in lipid peroxidation and enzyme activities of catalase and glutathione-S-transferase. On the contrary, nickel treatment to normal rats caused a significant inhibition in the levels of reduced glutathione. Superoxide dismutase activity was found to be decreased which however was not significant. Interestingly, when Zn was supplemented to nickel treated rats, the activities of catalase, and glutathione-S-transferase and the levels of GSH and lipid peroxidation came back to within normal limits. Activities of serum AST and ALT were increased significantly following nickel treatment to normal rats. Simultaneous zinc administration to nickel treated rats tended to restore the altered levels of AST and ALT. Normal control and zinc treated animals revealed normal histology of liver. On the other hand, nickel treated animals showed alterations in normal hepatic histoarchitecture which comprise of vacuolization of the hepatocytes and dilatation of sinusoids as well as increase in the number of bi-nucleated cells. Administration of zinc to nickel treated rats resulted in marked improvement in the structure of hepatocytes, thus emphasizing the protective potential of zinc in restoring the altered hepatic histoarchitecture. The nickel administration to normal rats indicated increased concentrations of nickel and decreased concentrations of zinc. However, zinc effectively brought the altered levels of nickel and zinc to within normal range. The study concludes that zinc has the potential in alleviating the toxic effects of nickel in rat liver because of its property to induce metallothionein (S-rich protein) as a free radical scavenger, or its indirect action in reducing the levels of oxygen reactive species.
...
PMID:Protective role of zinc in nickel induced hepatotoxicity in rats. 1553 90

The aim of this study is to examine the relationship between alcohol dependence and oxidative status. The biochemical parameters and antioxidants status were measured among 28 patients with alcohol dependence. Nineteen healthy persons without drinking problem were recruited as the control subjects. The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (gamma-GT), and levels of cholesterol, triglyceride (TG), and uric acid were significantly increased in the specimen of patients compared with control. Serum malondialdehyde (MDA) levels of the patients were found to be significantly increased compared with controls and decreased after abstinence. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were, respectively, 86% and 37% lower in alcoholic patients. After 14 d of abstinence, SOD activity was significantly reduced by 85%, CAT by 52%, and GPX by 54%, whereas no change was found in activity of glutathione reductase (GR). The duration of alcohol dependence is significantly correlated with the levels of MDA. In addition, the activity of CAT was significantly correlated with MDA levels. The results of this study suggest that oxidative stress occurred during alcohol dependence and subsequently affected the antioxidants mechanisms.
...
PMID:Oxidative status in patients with alcohol dependence: a clinical study in Taiwan. 1607 62

Nitrosamine compounds are known hepatic carcinogens. In the metabolism of nitrosamines, such as N-nitrosodiethylamine (NDEA), there is evidence of the formation of reactive oxygen species (ROS) resulting in oxidative stress, which may be one of the factors in the etiology of cancer. The formation of ROS may alter the antioxidant system, while the presence of Vitamin E may counteract NDEA induced oxidative stress. This study was planned to determine whether pre-treatment with Vitamin E (40 mg/kg body weight, i.p., twice a week for 4 weeks) to NDEA induced rats provides protection against oxidative stress in liver caused by the carcinogen. A single necrogenic dose of NDEA (200mg/kg body weight) was administered i.p. to the male albino rats with or without Vitamin E pre-treatment and the animals were sacrificed on Days 7, 14 or 21 after the administration of NDEA. The result showed enhanced levels of hepatic lipid peroxidation (LPO) and conjugated dienes of NDEA treated rats as the indices of oxidative stress, however, Vitamin E pre-treated rats administered NDEA showed decreased LPO and conjugated dienes (Day 21). Superoxide dismutase (SOD) activity in liver was not altered significantly in NDEA treated rats with or without Vitamin E pre-treatment. Catalase (CAT) activity was inhibited with NDEA treatment, however, Vitamin E pre-treatment showed recovery in hepatic CAT activity (Days 14 and 21). Total and Se-glutathione peroxidase (GSH-Px) activities and glutathione-S-transferase (GST) activity in liver increased in NDEA treated rats irrespective of Vitamin E pre-treatment. Glutathione reductase (GSH-R) activity as well as total glutathione (GSH) content in liver decreased in NDEA treated animals, both of which were recovered in Vitamin E pre-treated rats administered NDEA. Activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were increased significantly following NDEA treatment to rats with or without Vitamin E pre-treatment. The activities of AST and ALT enzymes were significantly reduced on Days 14 and 21 and ALP activity was reduced on Day 21 in NDEA+Vitamin E treated animals when compared to NDEA treated alone. LDH enzyme activity was normalized on Day 14 in Vitamin E pre-treated animals administered NDEA. However, the AST, ALT and ALP enzyme activities remained high in all treatment groups as compared to control group. Normal control and Vitamin E treated alone rats revealed normal histology of liver. On the other hand, NDEA treated animals showed alterations in normal hepatic histoarchitecture, which comprised of necrosis and vacuolization of the cells. However, the rats treated with Vitamin E+NDEA showed that the liver cells were normal, with very little necrosis (Day 21). This study concludes that the pre-treatment with Vitamin E prior to the administration of NDEA, reduced the degree of oxidative stress, although this vitamin produced only slight changes in the hepatic injury, in a time-dependent manner.
...
PMID:Protective role of Vitamin E pre-treatment on N-nitrosodiethylamine induced oxidative stress in rat liver. 1614 95


1 2 3 4 5 Next >>

---