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)

To determine if impaired intestinal absorption contributes to the folate deficiency observed in chronic alcoholics, we assessed in vivo folate absorption in Hanford mini-pigs fed ethanol with an adequate diet. Sixteen minipigs were pair-fed diets supplemented with ethanol or sucrose to 60% of total calories for 11 mo. In the ethanol-fed pigs peak blood alcohol concentrations averaged 28 mmol/L, serum alanine transaminase and aspartate transaminase activities were elevated, and liver histology showed a centrilobular distribution of succinate dehydrogenase. Tissue folate concentrations were comparable in both groups. The jejunal uptake of folic acid, measured by intestinal perfusion, was similar in both groups of animals and was not affected by acute exposure to 445 mmol/L ethanol. The in vivo hydrolysis of polyglutamyl folate was reduced by 35% in one ethanol-fed minipig. Decreased hydrolysis of polyglutamyl folate may represent an early step in the development of folate deficiency in chronic alcoholics.
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PMID:Folate absorption in alcoholic pigs: in vivo intestinal perfusion studies. 259 32

Alcoholic liver disease is associated with abnormal hepatic methionine metabolism and folate deficiency. Because folate is integral to the methionine cycle, its deficiency could promote alcoholic liver disease by enhancing ethanol-induced perturbations of hepatic methionine metabolism and DNA damage. We grouped 24 juvenile micropigs to receive folate-sufficient (FS) or folate-depleted (FD) diets or the same diets containing 40% of energy as ethanol (FSE and FDE) for 14 wk, and the significance of differences among the groups was determined by ANOVA. Plasma homocysteine levels were increased in all experimental groups from 6 wk onward and were greatest in FDE. Ethanol feeding reduced liver methionine synthase activity, S-adenosylmethionine (SAM), and glutathione, and elevated plasma malondialdehyde (MDA) and alanine transaminase. Folate deficiency decreased liver folate levels and increased global DNA hypomethylation. Ethanol feeding and folate deficiency acted together to decrease the liver SAM/S-adenosylhomocysteine (SAH) ratio and to increase liver SAH, DNA strand breaks, urinary 8-oxo-2'-deoxyguanosine [oxo(8)dG]/mg of creatinine, plasma homocysteine, and aspartate transaminase by more than 8-fold. Liver SAM correlated positively with glutathione, which correlated negatively with plasma MDA and urinary oxo(8)dG. Liver SAM/SAH correlated negatively with DNA strand breaks, which correlated with urinary oxo(8)dG. Livers from ethanol-fed animals showed increased centrilobular CYP2E1 and protein adducts with acetaldehyde and MDA. Steatohepatitis occurred in five of six pigs in FDE but not in the other groups. In summary, folate deficiency enhances perturbations in hepatic methionine metabolism and DNA damage while promoting alcoholic liver injury.
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PMID:Folate deficiency disturbs hepatic methionine metabolism and promotes liver injury in the ethanol-fed micropig. 1212 4

This study aims to determine serum folate and plasma homocysteine levels in healthy pregnant women following a live birth and compare them with healthy non-pregnant women. Fifty healthy gravid multiparous women are included in the study and 25 normal non-pregnant female subjects act as controls (group I). The pregnant women are divided into two groups according to interpregnancy interval: group II (six months or less); group III (18-24 months). Venous blood samples are analysed for red blood cell folate and homocysteine, vitamin B12, serum folate and albumin, and serum aminotransferases (ALT and AST). There was a significant decrease in red cell folate and serum folate in group II compared to the control group (P<0.001). Serum vitamin B12 showed no significant difference. Plasma homocysteine and serum albumin showed significant decreases in both groups II and III compared to the control group. (P<0.001) There was significant positive correlation between homocysteine and serum albumin in the three studied groups. (r=0.42, P<0.001; r=0.45, P<0.001; r=0.51, P<0.001, respectively). There was significant negative correlation between red cell folate and homocysteine in the three studied groups. (r=-0.48, P<0.001; r=-0.53, P<0.001; r=-0.49, P<0.001, respectively). Two cases in group II showed signs of intrauterine growth retardation. The results suggest that pregnant females with short interpregnancy intervals are more likely to develop folate deficiency. Educational strategies are required to increase folate awareness among women to promote the benefits of folic acid supplementation. Mandatory folate fortification of foods should be defined and monitored.
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PMID:Folate and homocysteine levels in pregnancy. 1525 Jun 71

Mitochondrial (mt) DNA deletions and low folate status, proposed characteristics of carcinogenesis, in relation to human hepatocellular carcinoma (HCC) susceptibility are not clearly understood. We hypothesised that low folate status may modify frequencies of mtDNA deletions in humans, both of which could predispose individuals to HCC development. Biochemical folate status of serum and lymphocytes, and frequencies of mtDNA deletions in lymphocytes were determined in ninety HCC cases and ninety cancer-free healthy controls, individually matched by age and sex. The data revealed that HCC patients had lower levels of serum folate (P = 0.0002), lymphocytic folate (P = 0.040) and accumulated higher frequency of lymphocytic mtDNA deletions (P < 0.0001) than the controls. In the total studied subjects, frequencies of lymphocytic mtDNA deletions were associated with hepatitic B infection (P = 0.004) and HCC incidents (P = 0.001), and were correlated with serum folate (r - 0.155; P = 0.041), lymphocyte folate (r - 0.314; P = 0.0001), levels of glutamate-oxaloacetate transaminase (GOT) (r 0.206; P = 0.006), glutamate-pyruvate transaminase (GPT) (r 0.163; P = 0.037) and alpha-fetal protein concentrations (r 0.212; P = 0.005). After adjustment for age, sex, lifestyle and one-carbon metabolite factors, individuals with low blood folate ( < 11.5 nmol/l) or high mtDNA deletions (Delta threshold cycle number (Ct)>5.3) had increased risks for HCC (OR 7.7, 95 % CI 1.9, 29.9, P = 0.003; OR 5.4; 95 % CI 1.7, 16.8, P = 0.003, respectively). When combined with folate deficiency (serum folate < 14 nmol/l), the OR of HCC in individuals with high levels of lymphocytic mtDNA deletions was enhanced (OR 13.3; 95 % CI 1.45, 122; P = 0.008). Further controlling for GOT and GPT levels, however, negated those effects on HCC risk. Taken together, the data suggest that biochemical folate status and liver injuries are important modulators to lymphocytic mtDNA deletions. The mt genetic instability that results from a high rate of mtDNA deletions and/or low folate status increased the risk for HCC, which is mediated by clinical hepatic lesions.
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PMID:Lymphocytic mitochondrial DNA deletions, biochemical folate status and hepatocellular carcinoma susceptibility in a case-control study. 1933

Folate deficiency and hyperhomocysteinemia are found in most patients with alcoholic liver disease. Oxidative stress is one of the most important mechanisms contributing to homocysteine (Hcy)-induced tissue injury. However it has not been examined whether exogenous administration of folic acid attenuates oxidative stress and hepatic toxicity. The aim of this study was to investigate the in vivo effect of folic acid supplementation on oxidative stress and hepatic toxicity induced by chronic ethanol consumption. Wistar rats (n = 32) were divided into four groups and fed 0%, 12%, 36% ethanol, or 36% ethanol plus folic acid (10 mg folic acid/L) diets. After 5 weeks, chronic consumption of the 36% ethanol diet significantly increased plasma alanine transaminase (ALT) (P < 0.05) and aspartate transaminase (AST) (P < 0.05), triglycerides (TG) (P < 0.05), Hcy (P < 0.001), and low density lipoprotein conjugated dienes (CD) (P < 0.05) but decreased total radical-trapping antioxidant potential (TRAP) (P < 0.001). These changes were prevented partially by folic acid supplementation. The 12% ethanol diet had no apparent effect on most parameters. Plasma Hcy concentration was well correlated with plasma ALT (r = 0.612(**)), AST (r = 0.652(*)), CD (r = 0.495(*)), and TRAP (r = -0.486(*)). The results indicate that moderately elevated Hcy is associated with increased oxidative stress and liver injury in alcohol-fed rats, and suggests that folic acid supplementation appears to attenuate hepatic toxicity induced by chronic ethanol consumption possibly by decreasing oxidative stress.
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PMID:Folic acid supplementation reduces oxidative stress and hepatic toxicity in rats treated chronically with ethanol. 2225 76