Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17174 (aspartate aminotransferase)
 14,872 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alcohol abuse is usually regarded as the most likely cause of elevated serum liver enzyme values in those attending for well population screening, but we have found increased body weight to be an important contributing factor. We have measured serum levels of alanine amino-transferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) in approximately 21,000 men attending for routine health screening, and related these to behavioural factors such as alcohol consumption, cigarette smoking, exercise level and obesity. The levels of all three enzymes were positively correlated with levels of alcohol consumption. Decreasing levels of physical activity were associated with increases in mean ALT and GGT levels. Cigarette smoking showed only a weak effect on ALT and AST, which became non-significant after multivariate statistical analysis, but increasing consumption of cigarettes was associated with increased mean levels of GGT. In contrast, all three enzymes showed marked increases in mean levels with increasing body mass index (BMI). The effect of obesity was particularly important in the case of ALT: the prevalence of increased ALT values in obese subjects (BMI greater than or equal to 31 kg/m2) was more than eight times that in those with normal weight (BMI less than or equal to 25 kg/m2), even after allowing for the confounding effect of alcohol consumption. This study is concerned solely with male subjects, but we hope to extend the analysis to females in the near future.
Ann Clin Biochem 1989 Sep
PMID:Effect of body mass and other factors on serum liver enzyme levels in men attending for well population screening. 257 11

The activity of dipeptidyl aminopeptidase IV was studied in the sera of 378 hospitalized patients. The mean activity of dipeptidyl aminopeptidase IV was elevated significantly in patients with neoplasmata and hepatitis, but not in patients with liver cirrhosis. Significant correlations (p less than 0.001) existed with gamma-glutamyl transferase, glutamate dehydrogenase, alkaline phosphatase and leucine aminopeptidase. A significant correlation with lactate dehydrogenase existed only in patients with neoplasmata. Principal component analysis, performed with aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, leucine aminopeptidase, lactate dehydrogenase and dipeptidyl aminopeptidase IV, revealed correlations between the activities of aspartate aminotransferase and alanine aminotransferase, and between alkaline phosphatase and leucine aminopeptidase, but neither dipeptidyl aminopeptidase IV nor lactate dehydrogenase showed any correlation with either of these two groups. In lectin affinity chromatography with concanavalin A and wheat germ lectin sepharose, serum dipeptidyl aminopeptidase IV from liver cirrhosis patients showed the same binding pattern as that from healthy subjects. The activity and glycosylation of dipeptidyl aminopeptidase IV in serum and hepatic plasma membranes was investigated in rats, following the induction of hepatitis with galactosamine. In the serum, dipeptidyl aminopeptidase IV activity was elevated as early as 6 h after galactosamine injection, and the elevated activity persisted until the 7th day. At the same time dipeptidyl aminopeptidase IV activity was also elevated in the hepatic plasma membrane. Ninety eight percent of hepatic dipeptidyl aminopeptidase IV bound to concanavalin A as well as to wheat germ lectin and this value was unchanged during hepatitis. In the serum of control rats, 90% of dipeptidyl aminopeptidase IV bound to concanavalin A but only 39% to wheat germ lectin.(ABSTRACT TRUNCATED AT 250 WORDS)
J Clin Chem Clin Biochem 1989 Sep
PMID:[Dipeptidyl aminopeptidase IV in hospitalized patients and in galactosamine hepatitis of the rat: Activity and lectin affinity chromatography in serum and hepatic plasma membranes]. 257 17

Rats were injected intraperitoneally with CCl4 (2.5 ml/kg body wt.) and the hepatotoxicity was compared with that of rats receiving the same dose of CCl4 and an intraperitoneal injection of fructose 1,6-bisphosphate (2 g/kg body wt.). A 50-70% decrease in plasma aspartate aminotransferase and alanine aminotransferase activities was observed in the latter treatment, indicating a protective role of the sugar bisphosphate in CCl4 hepatotoxicity. The protection was accompanied by elevated hepatic activities of ornithine decarboxylase at 2, 6 and 24 h, S-adenosylmethionine decarboxylase at 6 h, and spermidine N1-acetyltransferase at 2 h. The increase in the enzymes involved in polyamine metabolism was shown in our previous work [Rao, Young & Mehendale (1989) J. Biochem. Toxicol. 4, 55-63] to correlate with increased polyamine synthesis or interconversion, which was related to the extent of hepatocellular regeneration. The hepatic contents of fructose 1,6-bisphosphate and ATP significantly decreased after CCl4 treatment, and administration of the sugar bisphosphate increased hepatic ATP. Fructose 1,6-bisphosphate, an intermediary metabolite of the glycolytic pathway, may decrease CCl4 toxicity by increasing the ATP in the hepatocytes. The ATP generated is useful for hepatocellular regeneration and tissue repair, events which enable the liver to overcome CCl4 injury.
Biochem J 1989 Sep 15
PMID:Protective role of fructose 1,6-bisphosphate during CCl4 hepatotoxicity in rats. 259 Jan 62

The results from an external quality control of dry-chemistry instruments are presented. The performance with regard to imprecision was good. With regard to accuracy, the performance was poor for aspartate aminotransferase, creatine kinase, lactate dehydrogenase, triglycerides and uric acid. The inaccuracy of alanine aminotransferase, bilirubin, cholesterol, creatinine, glucose and potassium was comparable to that obtained by hospital instruments using wet chemistry. There were no large differences with respect to quality between Seralyzer and Reflotron. However, Seralyzer users performed more analyses per week, analysed a higher number of constituents and had more experienced operators than the Reflotron users. Reflotron users more often analysed the sample in connection with the consultation. The importance of an established quality control programme for these instruments is underlined.
Scand J Clin Lab Invest 1989 Sep
PMID:Performance of dry-chemistry instruments in primary health care. 259 43

Effects of high doses of cobra venom, (150 micrograms/120 +/- 20 g body wt) and viper venom (300 micrograms/120 +/- 20 g body wt) on aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), acetylcholinesterase (ACh) and alkaline phosphatase (ALP) of brain of albino rats were studied. While AST, LDH, ACh and ALP activities increased in both viper and cobra venom treated rats, ALT decreased in both groups compared to control.
Indian J Exp Biol 1989 Sep
PMID:Effect of envenomation on enzymes of brain of albino rats. 263 6

To determine whether liver function tests and clinical and demographic information would predict methotrexate-associated hepatotoxicity, we identified 78 patients who had undergone 147 liver biopsies associated with methotrexate therapy for psoriasis. The joint sensitivity of aspartate aminotransferase, alkaline phosphatase, and total bilirubin values in detecting abnormal results from a biopsy specimen obtained after treatment was .86; the predictive value of negative test results was .93. A logistic regression model significantly predicted the presence of abnormal (grade III or higher) liver biopsy specimen results. The concordance index was .92 (perfect, 1.0). Regression coefficients may be used along with information from a specific patient to calculate the predicted probability of an abnormal result from a liver biopsy specimen after treatment. We conclude that this multivariate risk estimation model significantly predicts the likelihood of positive findings from liver biopsy specimens in this patient population. The clinical use of this model awaits further validation.
Arch Dermatol 1989 Sep
PMID:Detection of hepatotoxicity associated with methotrexate therapy for psoriasis. 277 96

The effects on metabolism of the fluorinated dicarboxylic acid, perfluorosuccinate, were examined in hepatocytes from fasted rats. Perfluorosuccinate (5 mM) inhibited gluconeogenesis from lactate by 80% and from pyruvate by 40%. Significant inhibition (up to 30%) occurred at a concentration of perfluorosuccinate of 50 microM. Cellular ATP levels were not affected by perfluorosuccinate, nor was the rate of formation of ketone bodies from palmitate, although the ratio [3-hydroxybutyrate]/[acetoacetate] was increased up to 5-fold relative to the control. An increased concentration of cellular L-malate was measured in the presence of perfluorosuccinate but this did not reflect inhibition of malate transport between the mitochondrial and cytoplasmic compartments. In addition, ethanol oxidation by hepatocytes was inhibited 25% by 1 mM perfluorosuccinate. Ureogenesis from ammonia was relatively insensitive to inhibition by perfluorosuccinate. In cytoplasmic extracts of rat liver, the activities of phosphoenolpyruvate carboxykinase and aspartate aminotransferase were inhibited 40-50% and 23%, respectively, by 1 mM perfluorosuccinate. The observed metabolic effects of perfluorosuccinate are consistent with inhibition of the activities of phosphoenolpyruvate carboxykinase and aspartate aminotransferase within the cytoplasm.
Biochem Pharmacol 1989 Sep 01
PMID:The characterization of perfluorosuccinate as an inhibitor of gluconeogenesis in isolated rat hepatocytes. 277 10

The high-Mr isoenzyme of alkaline phosphatase (AP, EC 3.1.3.1), a highly sensitive index to cholestasis, was measured by liquid chromatography in 45 patients with cystic fibrosis. Results of serum tests for liver dysfunction--including gamma-glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, total AP, bilirubin, and bile acids--were compared with those for high-Mr AP. Values for high-Mr AP were increased in 44.4% of our patient population, with activities ranging from 0.4 to 17.3 U/L. The upper limit in the control group was 2.5 U/L. We find increased high-Mr AP to be a more sensitive indicator of liver dysfunction in patients with cystic fibrosis than are other tests.
Clin Chem 1989 Sep
PMID:High-molecular-mass ("biliary") isoenzyme of alkaline phosphatase and the diagnosis of liver dysfunction in cystic fibrosis. 277 12

The localization of the human genes for cytosolic and mitochondrial aspartate aminotransferase (AspAT) has been determined by chromosomal in situ hybridization with specific human cDNA probes previously characterized in our laboratory. The cytosolic AspAT gene is localized on chromosome 10 at the interface of bands q241-q251. Mitochondrial AspAT is characterized by a multigene family located on chromosomes 12 (p131-p132), 16 (q21), and 1 (p32-p33 and q25-q31). Genomic DNA from ten blood donors was digested by ten restriction enzymes, and Southern blots were hybridized with the two specific probes. Restriction fragment length polymorphism was revealed in only one case for cytosolic AspAT, with PvuII, while no polymorphism for mitochondrial AspAT was found.
Hum Genet 1989 Sep
PMID:Chromosomal localization of human aspartate aminotransferase genes by in situ hybridization. 277 55

To identify the mechanisms of reduced bile flow after hypertonic amino acid and glucose infusion, acute experiments were performed on anesthetized pigs. When secretin was not administered, amino acids or glucose reduced bile acid-dependent bile secretion to 65 +/- 3% of control. During secretin stimulation amino acids or glucose diminished bile acid-independent bile secretion to 78 +/- 2% of control. No changes in serum bilirubin, alanine aminotransferase, and aspartate aminotransferase were observed. Amino acids and glucose attack different mechanisms responsible for bile formation, but the result is that when secretin is not administered, biliary secretion of bile acids is reduced, and, accordingly, bile acid-dependent bile flow diminished. During secretin stimulation biliary NaHCO3 secretion is depressed, accounting for a fall in bile acid-independent bile flow. Amino acids exert no effect on bile acid secretion or, as a result, on bile acid-dependent bile flow after secretin infusion.
Scand J Gastroenterol 1989 Sep
PMID:Amino acid- and glucose-induced cholestasis before and during secretin stimulation. 279 88


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