Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.1 (aspartate aminotransferase)
 21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum activities of alanine-aminotransferase (ALAT, EC 2.6.1.2), aspartate-aminotransferase (ASAT, EC 2.6.1.1), lactate dehydrogenase (LDH, EC 1.1.1.27), and alkaline phosphatase (AP, EC 3.1.3.1) were increased significantly after a dose of 0.16 g/kg/b. w. (ip.) carbon tetrachloride (tetrachloromethane) in rats pretreated with 10% (v/v) ethanol for one and 10 weeks in comparison with water/carbon tetrachloride-treated animals. At the end of 30 and 52 weeks of ethanol consumption these levels were very slightly increased or not detectable. Ethanol treatment alone did not cause an increase in serum enzyme activities or histological liver damage, but caused a diminished intake of fluid and food and in some cases also a reduction of weight gain in the animal body. Significant decrease in body weight after carbon tetrachloride was more evident in rats pretreated with ethanol (1 week greater than 10 greater than or equal to 52 weeks) than in water drinking animals, the lethality caused by carbon tetrachloride was also higher after one and 10 weeks than after 30 to 52 weeks of ethanol pretreatment. The results indicate a decrease of carbon tetrachloride toxicity with increased duration of ethanol pretreatment. This phenomenon could be attributed to reduced sensibility to those alcohol effects which are responsible for increase of carbon tetrachloride toxicity.
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PMID:Influence of ethanol pretreatment of differing duration on toxic effects of carbon tetrachloride in rats. 208 Sep 8

Two decades of research in ethanol metabolism have culminated in the molecular elucidation of an ethanol-inducible cytochrome P450 (P450IIE1) which is not only involved with ethanol metabolism and ethanol tolerance, but also with the activation of a number of xenobiotics. The unique ability of P450IIE1 to activate xenobiotic agents now appears to be responsible for the increased susceptibility of the heavy drinker to hepatotoxic industrial solvents, commonly used drugs, over-the-counter medications and chemical carcinogens. It also explains some of the interaction of ethanol with nutritional factors, such as hepatic vitamin A: enhanced microsomal degradation of retinoids (together with hepatic mobilisation) promotes depletion. Treatment, however, is complicated by the fact that ethanol also enhances the toxicity of excess vitamin A. All pathways of ethanol metabolism result in the production of acetaldehyde, the toxicity of which has been reviewed (Lieber 1982). New aspects discussed here include the formation of acetaldehyde-protein adducts and an associated immune response that may play a pathogenic role. Also discussed are the implications of ethanol-induced alterations in microtubules, mitochondria and plasma membranes, as they relate, in part, to accompanying acetaldehyde-induced toxicity, to the production of free radicals or to lipid peroxidation-mediated injury associated with glutathione depletion. There is also depletion of S-adenosyl-L-methionine (SAMe). Administration of synthetic SAMe results in a partial correction of the SAMe depletion and a consequent restoration of glutathione levels. Other beneficial effects of SAMe include a significant attenuation of the increase in plasma aspartate transaminase and glutamate dehydrogenase activities. Mitochondrial damage, including giant forms, documented by light and electron microscopy, is also attenuated by SAMe. Thus, the new understanding of the pathophysiology of alcohol-induced liver damage has led to more successful therapy with drugs and nutritional factors.
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PMID:Interaction of alcohol with other drugs and nutrients. Implication for the therapy of alcoholic liver disease. 208 78

Ethanol has profound effects on cellular function, causes hormonal imbalance and either directly or indirectly results in nutritional deficiencies. Together with genetic and environmental factors these metabolic changes eventually cause functional and structural damage to liver, heart, central nervous system and other organs. In order to prevent organ injury the early recognition of the alcoholic patient is important. The combination of physician interview, questionnaire and laboratory markers of ethanol abuse [MCV, GGT, AST and others] is useful for the diagnosis of alcoholism. Abstinence is the most important therapeutic measure. The treatment of organ damage has so far been symptomatic. Initial results of trials of specific treatment of alcoholic liver disease are encouraging.
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PMID:[Biological changes caused by ethanol: their sequelae and importance in the diagnosis of alcoholism]. 219 96

Various aliphatic alcohols potentiate the toxicity of a wide range of xenobiotics including several haloalkanes. The present series of experiments were designed to test: (i) whether a single subtoxic dose of alcohol can potentiate CCl4 and CHCl3 hepatoxicity, and (ii) whether this potentiation leads to greater animal lethality. Selected members of a homologous series of straight chain alcohols were chosen for this study. Methanol, ethanol, isopropanol, t-butanol, pentanol, hexanol, octanol, decanol, and eicosanol at equimolar doses (10 mmol/kg) were tested in the present investigation. Each alcohol was administered orally to male Sprague-Dawley rats (175-250 g) 18 hr prior to a single oral administration of CCl4 or CHCl3. Liver injury was assessed by plasma transaminases (alanine aminotransferase, ALT; aspartate aminotransferase, AST) and histopathological examination of liver sections 24 hr after the halomethane treatment. None of these alcohols alone increased plasma ALT or AST significantly, whereas CCl4 or CHCl3 administration to alcohol-treated animals resulted in significant elevation of plasma transaminases. Eicosanol (20-carbon alcohol) did not potentiate the toxicity of either halomethane. Methanol, ethanol, isopropanol, and decanol in combination with CCl4 caused massive liver damage but failed to augment CCl4 lethality. t-Butanol, pentanol, hexanol, and octanol significantly decreased the LD50 of CCl4. The hepatotoxic effects of CHCl3 were potentiated by all of the alcohols and the LD50s were also decreased significantly. On a comparative basis, alcohol-potentiated CHCl3 toxicity was greater than the toxicity of CCl4. These findings indicate that even though halomethane liver injury might be potentiated by alcohols, the underlying mechanisms differ among alcohols since not all alcohols potentiate the lethal effects of these halomethanes.
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PMID:Potentiation of CCl4 and CHCl3 hepatotoxicity and lethality by various alcohols. 225 8

The present investigation examines the possibility that Cd and ethanol have a significant toxicological interaction. This examination was warranted as exposure to either chemical is known to compromise human health. Inasmuch as both chemicals affect the morphology, biochemistry, and physiology of liver, it seemed reasonable to consider liver as a possible site of interaction. Specifically, the hypothesis that ethanol alters the hepatotoxic action of Cd was evaluated. Accordingly, male rats were injected iv with hepatotoxic (3.0 mg/kg) or lethal (4.5 mg/kg) dosages of Cd, 24 hr after single-dose ethanol administration (7 g/kg, po). Cd-induced hepatotoxicity was assessed by measuring the activities of alanine aminotransferase, aspartate aminotransferase, and sorbitol dehydrogenase in serum collected 10 hr after Cd injection. Lethality was assessed by recording the number of survivors over a 7-day period. Prior exposure to ethanol substantially reduced the lethal and hepatotoxic properties of Cd. Two mechanisms were evaluated in an effort to explain ethanol-induced suppression of Cd hepatotoxicity. Ethanol pretreatment was postulated to: (1) enhance Cd excretion in bile thereby decreasing hepatic Cd content and/or (2) reduce the interaction between Cd and target sites in liver such as organelles and cytosolic high-molecular-weight (HMW) proteins. The first proposed mechanism was incorrect as the biliary excretion of Cd was nearly abolished and the concentration of Cd in whole liver increased (33%) as a result of ethanol exposure. The second proposed mechanism was a plausible explanation of ethanol-induced suppression of Cd hepatotoxicity because ethanol pretreatment decreased (approximately 60%) the content of Cd in nuclei, mitochondria, and endoplasmic reticulum, and nearly eliminated the association of Cd with cytosolic HMW proteins. Reduction in the concentration of Cd in potential target sites of intoxication was caused by a metallothionein-promoted sequestration of Cd in cytosol.
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PMID:Ethanol decreases cadmium hepatotoxicity in rats: possible role of hepatic metallothionein induction. 226 92

This article examines the commonly used laboratory indicators of heavy alcohol use (elevated MCV, GGTP and AST values) in subgroups of drug-using and non-drug-using alcoholic men admitted to an inpatient alcoholism treatment program. A total of 380 consecutive admissions meeting DSM-III diagnostic criteria for alcohol use or dependence were studied. Of these subjects, 75% used both alcohol and drugs. The most frequently used drugs were marijuana, cocaine, amphetamines and tranquilizers. Overall, subjects who used drugs with alcohol had significantly lower MCV and GGTP values than subjects who used alcohol alone. More specifically, cocaine use was associated with lower MCV values, marijuana use with lower AST values and heroin use with higher AST and GGTP values. These differences between drug-using and non-drug-using alcoholics were significant even after controlling for variables that affect the laboratory values such as age, quantity, frequency and duration of alcohol consumption. These findings indicate that any study of laboratory markers of alcoholism needs to consider concomitant illicit drug use patterns.
J Stud Alcohol 1990 Jul
PMID:Effect of combined substance use on laboratory markers of alcoholism. 235 10

The present experiments were designed to study the effect of chronic ethanol consumption on endotoxin toxicity. The intravenous injection of endotoxin produced a more pronounced increase of serum AST and ALT activities in chronic ethanol-fed rats, when compared to controls. The activities of hepatic mitochondrial enzymes, succinate dehydrogenase and cytochrome oxidase, were also distinctly decreased by endotoxin treatment in chronic ethanol-fed rats. Consistent with these biochemical alterations, light and electron microscopic examinations revealed severe liver injury after endotoxin injection in chronic ethanol-fed rats. Furthermore, the increase of blood BUN and creatinine levels accompanied by the degeneration of the renal tubulus and slight infiltration of neutrophils into the glomerule were produced by endotoxin treatment and were more conspicuous in chronic ethanol-fed rats than controls. Therefore, the biochemical and histological evidence indicates that endotoxin markedly potentiates organ injury after chronic ethanol consumption. In addition, a more pronounced decrease in blood antithrombin III activity accompanied by an increase in fibrin degradation product level in blood was recognized in chronic ethanol-fed rats receiving endotoxin, when compared to controls receiving endotoxin. This increase of blood fibrin degradation product level correlated well with the decrease of antithrombin III activity (r = -0.6116; p less than 0.005). These findings of blood antithrombin III activity and fibrin degradation product level indicate that the coagulation-fibrinolysis system is more activated by endotoxin treatment after chronic ethanol consumption. Furthermore, the activation of the coagulation-fibrinolysis system was well correlated with biochemical and histological alterations representing hepatorenal involvement.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endotoxin-induced hypercoagulability: a possible aggravating factor of alcoholic liver disease. 254 Oct 59

Two recently proposed biochemical markers of alcoholism, namely, quantitation of plasma transferrin variant (Tf5.7) and the ratio of plasma mitochondrial aspartate aminotransferase (m-AspAT) to total AspAT (t-AspAT), were tested for their ability to detect young adult alcoholics. Another commonly used biochemical test, namely, activity of plasma gamma glutamyltransferase (GGT) was included as a comparison. Although mean values of GGT, TF5.7, total transferrin (Tftot), m-AspAT and t-AspAT in alcoholics were significantly higher than those in controls, there were too many overlapping values in each test between alcoholics and controls to render any of these tests suitable as a marker for young adult alcoholics. Depending on cut-off limits, the sensitivity of each test ranged from 0-52% and the specificity ranged from 80-97%. Moreover, the m-AspAT/t-AspAT and Tf5.7/Tftot ratios were not significantly different between alcoholics and controls. A stepwise linear discriminant function analysis of all the variables resulted in a slight increase in classification sensitivity (66%) but a decrease in specificity (77%). The relatively short duration (mean = 5.6 years) of heavy alcohol intake and the time elapsed (mean = 5.8 days) since the alcoholics last consumed alcohol very likely contributed to the low sensitivity. Young adults might also be more resilient with regard to the damaging biochemical effects of ethanol. Abnormal biochemical values might reverse to normal values much more quickly in young adult alcoholics than in those who are older and have more years of alcohol abuse.
Drug Alcohol Depend 1989 Jan
PMID:Transferrin and mitochondrial aspartate aminotransferase in young adult alcoholics. 256 67

The 7 day-long intragastric administration of ethanol and ethyleneglycol in a dose of 1/3 DL50 was studied for its effect on the circadian variations of the aspartate aminotransferase activity (AST, EC 2.6, 1.1) in the liver, brain, myocardium and kidney of male rats. The ethanol and ethylene glycol administration reduced the mean circadian enzymic activity in the above organs. Moreover, ethanol significantly reduced the amplitude of circadian variations of the AST activity in the liver, brain and kidney, while ethylene glycol--in the liver, myocardium and kidney.
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PMID:[The effect of alcohols on daily variations in aspartate amino- transferase activity in rat organs]. 258 42

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


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