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)

It is well established that caloric restriction extends life span and significantly retards the rate of occurrence of most age-associated degenerative disease processes. A paucity of data exists relative to the mechanisms by which caloric restriction accomplishes these events. We have examined the effect of caloric restriction in rats on several hepatic enzymes of intermediary metabolism. The activities of glycolytic and supporting enzymes including lactate dehydrogenase, pyruvate kinase, sorbitol dehydrogenase, and alcohol dehydrogenase were all decreased in response to caloric restriction. Fructose 1-phosphate aldolase and creatine phosphokinase were not altered. Likewise, enzymes associated with lipid metabolism (malic enzyme and glycerokinase) were reduced (fatty acid synthetase was reduced, but not to a statistically significant degree). Activities of enzymes supporting gluconeogenesis (glutamate oxaloacetate transaminase, tyrosine aminotransferase, glutamate pyruvate transaminase, glutamate dehydrogenase, amino acid oxidase, malate dehydrogenase, and glucose 6-phosphatase) were either unchanged or increased significantly by caloric restriction. Glucagon levels were decreased. Comparisons between young ad libitum fed and older calorically restricted rats revealed similar but not identical metabolic activity. These results suggest that caloric restriction produces an effect on intermediary metabolism, favoring the role of glucagon and glucose synthesis; but limiting the role of insulin and glucose catabolism in the liver. The former observation provides for the efficient support of peripheral tissues and the latter a level of energy production necessary only for self maintenance. Limited lipid metabolism suggests decreased potential for fatty acid epoxide formation and free radical damage to cellular macromolecules. Additionally, caloric restriction may delay the progressive age associated changes in the activities of some of the enzymes investigated.
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PMID:Effect of chronic caloric restriction on hepatic enzymes of intermediary metabolism in the male Fischer 344 rat. 266 33

A comparative trial was conducted with the oral administration of zinc sulphate to pregnant cows and heifers aimed at influencing the selected metabolic parameters in the dam-calf line. The total daily ZnSO4.7H2O dose of 3 g (680 mg Zn++) was given to dry standing cows and heifers for 35 days on an average (15-65) before the expected date of calving. The breeding conditions in the stock were problematic: losses of calves suffered in the last half-a-year period were higher than 30% of born calves; the main causes of this high mortality were coli-septicaemia and coli-enteritis. As compared with the eight control animals, the experimental cows and heifers (12 head) exhibited a transient increase in zincaemia, followed by a tendency to proteinaemia; aspartate aminotransferase activity increased, total immunoglobulins remained unchanged, and decreases were recorded in the activities of alanine aminotransferase, alkaline phosphatase, creatine phosphokinase and aldolase. On the other hand, the concentration of total bilirubin tended to increase. In 77% of the cows and first-calvers of the experimental group the quality of colostrum complied with the standard; in the case of the control animals this proportion was 83%. Significant zincaemia occurred in the calves of the experimental cows between the first and 14th day of their age; no differences from the control calves were recorded in immunoglobulinaemia, proteinaemia, albuminaemia and in the activities of alanine aminotransferase and creatine phosphokinase. On the other hand, aspartate aminotransferase activity tended to grow and alkaline phosphatase activity tended to sink. Neonatal hyperbilirubinaemia disappeared within the first 14 days of age in both the experimental and the control calves. The results failed to show clearly that the intention to increase the values of the studied parameters of immunopoiesis was met.
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PMID:[Peroral administration of zinc sulfate to pregnant cows and its effect on selected metabolic indicators in the dam-calf lineage]. 273 89

Ten male Holstein-Friesian calves naturally infected by Mycobacterium paratuberculosis were experimentally re-infected orally at an average of 17 days. Monthly measurements were conduced of the following activities, in the period between post infection days 160 and 400: total protein (TPR), albumin (ALB), cholesterol (CHOL), triglycerides (TRIG), Zn and Cu concentrations as well as sorbitol dehydrogenase, lactate dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (alpha-HBDH), gamma-glutamyltransferase, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), alkaline phosphatase and fructose-1,6-diphosphate aldolase (ALD). TPR, ALB, TRIG, and CHOL were reduced by day 400, in conjunction with disorders of digestion and absorption. Increased activities of CK, ALD, LDH, alpha-HBDH, AST and ALT primarily indicated damage to skeletal muscle and/or liver. Serum CK and ALD activities as well as TRIG and TPR concentrations may serve as aids to specific diagnosis of paratuberculosis, particularly in the advanced stage of the disease.
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PMID:Experimental paratuberculosis (Johne's disease)--studies on biochemical parameters in cattle. 277 44

The effects of recombinant human interleukin-1 beta (rhIL-1 beta) on various serum constituents were studied following subcutaneous injection (12.5 or 125 micrograms/kg) in female Wistar rats. Protein electrophoresis and the determination of the serum concentrations of carboxypeptidase N (CPN), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, aldolase, total proteins, iron, urea, creatinine, and several amino acids were performed 12, 24, and 72 hr after injection. With both doses of rhIL-1 beta, iron, albumin, CPN, and lysine were significantly decreased whereas alpha 2-globulin, urea, and creatinine were significantly increased 12 hr after administration. Iron and CPN were still low after 24 hr but returned to normal levels after 72 hr. With the higher dose of rhIL-1 beta, only alanine and phenylalanine levels were increased after 12 and 72 hr, taurine after 12 hr, and methionine after 24 hr. There were no biochemical or histological signs of hepatotoxicity. The findings indicate that rhIL-1 beta produces a reversible alteration of various biochemical plasma constituents without any apparent signs of cytotoxicity. Moreover, the decrease in CPN observed may influence the degradation of inflammatory peptides.
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PMID:Recombinant human interleukin-1 beta decreases serum carboxypeptidase N and modifies serum amino acid concentrations in rats. 278 29

The stability and storage characteristics were studied of 11 bovine enzymes of potential clinical significance, namely, aldolase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, acetylcholinesterase, creatine kinase, gamma glutamyltransferase, glutathione peroxidase (GSH-Px), alpha-hydroxybutyrate dehydrogenase, lactate dehydrogenase and superoxide dismutase (SOD). Enzyme activities in fresh serum were compared with those in plasma containing various anticoagulants including lithium heparin, EDTA and oxalate/fluoride. The same preservatives were assessed for their effects on the whole blood activities of GSH-Px and SOD. Stabilities of enzymes in plasma and serum stored at room (+20 degrees C), refrigerator (4 degrees C) or deep freeze (-20 degrees C) temperatures were also compared. In addition, SOD and GSH-Px activities in samples stored, at the same temperatures, as whole blood or aqueous lysates were monitored.
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PMID:Stability and storage characteristics of enzymes in cattle blood. 286 28

The stability and storage characteristics were studied of 11 ovine enzymes of potential clinical significance, namely, aldolase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, acetylcholinesterase, creatine kinase, gamma glutamyltransferase, glutathione peroxidase (GSH-Px), alpha-hydroxybutyrate dehydrogenase, lactate dehydrogenase and superoxide dismutase (SOD). Enzyme activities in fresh serum were compared with those in plasma containing various anticoagulants including lithium heparin, EDTA and oxalate/fluoride. The same preservatives were assessed for their effects on the whole blood activities of GSH-Px and SOD. Stabilities of enzymes in plasma and serum stored at room (+20 degrees C), refrigerator (4 degrees C) or deep freeze (-20 degrees C) temperatures were also compared. In addition, SOD and GSH-Px activities in samples stored, at the same temperatures, as whole blood or aqueous lysates were monitored. The results are discussed with particular reference to the differences between sheep and cattle.
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PMID:Stability and storage characteristics of enzymes in sheep blood. 286 29

Energy metabolism in proliferating cultured rat thymocytes was compared with that of freshly prepared non-proliferating resting cells. Cultured rat thymocytes enter a proliferative cycle after stimulation by concanavalin A and Lymphocult T (interleukin-2), with maximal rates of DNA synthesis at 60 h. Compared with incubated resting thymocytes, glucose metabolism by incubated proliferating thymocytes was 53-fold increased; 90% of the amount of glucose utilized was converted into lactate, whereas resting cells metabolized only 56% to lactate. However, the latter oxidized 27% of glucose to CO2, as opposed to 1.1% by the proliferating cells. Activities of hexokinase, 6-phosphofructokinase, pyruvate kinase and aldolase in proliferating thymocytes were increased 12-, 17-, 30- and 24-fold respectively, whereas the rate of pyruvate oxidation was enhanced only 3-fold. The relatively low capacity of pyruvate degradation in proliferating thymocytes might be the reason for almost complete conversion of glucose into lactate by these cells. Glutamine utilization by rat thymocytes was 8-fold increased during proliferation. The major end products of glutamine metabolism are glutamate, aspartate, CO2 and ammonia. A complete recovery of glutamine carbon and nitrogen in the products was obtained. The amount of glutamate formed by phosphate-dependent glutaminase which entered the citric acid cycle was enhanced 5-fold in the proliferating cells: 76% was converted into 2-oxoglutarate by aspartate aminotransferase, present in high activity, and the remaining 24% by glutamate dehydrogenase. With resting cells the same percentages were obtained (75 and 25). Maximal activities of glutaminase, glutamate dehydrogenase and aspartate aminotransferase were increased 3-, 12- and 6-fold respectively in proliferating cells; 32% of the glutamate metabolized in the citric acid cycle was recovered in CO2 and 61% in aspartate. In resting cells this proportion was 41% and 59% and in mitogen-stimulated cells 39% and 65% respectively. Addition of glucose (4 mM) or malate (2 mM) strongly decreased the rates of glutamine utilization and glutamate conversion into 2-oxoglutarate by proliferating thymocytes and also affected the pathways of further glutamate metabolism. Addition of 2 mM-pyruvate did not alter the rate of glutamine utilization by proliferating thymocytes, but decreased the rate of metabolism beyond the stage of glutamate significantly. Formation of acetyl-CoA in the presence of pyruvate might explain the relatively enhanced oxidation of glutamate to CO2 (56%) by proliferating thymocytes.
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PMID:Glutamine and glucose metabolism during thymocyte proliferation. Pathways of glutamine and glutamate metabolism. 286 9

The high degree of constancy of enzyme catalytic activity in the plasma of a given individual is regulated by a complex system of flux equilibria consisting of eight basic processes. Some of these processes are of primarily theoretic importance. Enzymes from all tissues of the body, including the liver, are released via a continuous physiological process into the interstitial space and get into the intravascular space by way of lymphatic transport. The release of enzymes from tissues directly into the intravascular space is of secondary importance as is the exchange of enzyme molecules across capillary membranes from the intravascular to the interstitial space and vice versa. In contrast, enzymes from circulating blood cells are transported directly into the intravascular space. Enzymes are removed from the intravascular space at rates which vary greatly between both enzymes and species. In a review of the literature, half-lives of diagnostically important enzymes in plasma of man, dogs and rats were given and the striking differences in the results for a given enzyme are discussed from a methodological point of view. In a mathematical analysis, data for lymphatic transport of enzymes from dogs and rats (Lindena et al. (1986) this J. 24, 19-33) and of enzyme efflux from in vivo ageing erythrocytes (Lindena et al. (1986) this J. 24, 49-59) into the plasma are related to the elimination rate constants of enzymes from the plasma. The contribution of lymphatically transported enzymes to the basal catalytic activity in plasma (Lindena & Trautschold (1986) this J. 24, 11-18) amounts to 55-80% for lactate dehydrogenase and malate dehydrogenase, 80-90% for adenylate kinase and phosphohexose isomerase, 90-95% for aspartate aminotransferase and aldolase and 99% for creatine kinase. A model of Ca2+ -mediated vesicular transport of enzymes out of ageing erythrocytes is proposed. The importance of lymphatically transported enzymes to total plasma catalytic activity in dogs and rats argues for a similar contribution of lymph transport in man.
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PMID:Kinetic of adjustment of enzyme catalytic concentrations in the extracellular space of the man, the dog and the rat. Approach to a quantitative diagnostic enzymology, V. Communication. 351 20

Excessive fat accumulation in the liver is a common metabolic disorder seen in humans and animals. Fatty liver was induced in the rat by feeding the animals with a sucrose rich diet containing 1% orotic acid for 2-3 weeks. In the sera from fatty liver rats there were significant changes in the level of alanine aminotransferase (+ 68.7%), malic dehydrogenase (+ 77.8%), gamma-glutamyl transpeptidase (- 53.4%) and total lipids (+ 26.6%). There were small to no changes in the levels of aspartate aminotransferase, glucose-6-phosphate dehydrogenase, lactic dehydrogenase, aldolase, malic enzyme, 6-phosphogluconic acid dehydrogenase, alkaline phosphatase and albumin. In fatty liver, significant differences were seen in the levels of glucose 6-phosphate dehydrogenase (+ 235%), malic enzyme (+ 170%), gamma-glutamyl transpeptidase (+ 113%), 6-phosphogluconate dehydrogenase (+ 63%), aspartate aminotransferase (+ 35.6%), malic dehydrogenase (+ 38%), lactic dehydrogenase (+ 37%), and alanine aminotransferase (- 23%). Comparison of the non-fatty part with the fatty part of the fatty liver showed larger changes in the non-fatty part of the liver, suggesting that during the fattening process, there is an induction of enzymes in the liver reaching a peak prior to lipid accumulation, declining thereafter during liver fattening. The increase in NADPH-generating lipogenic enzymes suggests that accumulated fat in the liver is at least partially from de-novo increased synthesis in the liver.
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PMID:Biochemical changes in liver and blood during liver fattening in rats. 377 7

Common bile duct ligation (CBDL) in rats was used to induce liver disease and secondary kidney damage. The biochemical changes in the liver, kidney and plasma were studied at 3, 6, 10 and 21 days post CBDL. The observed alterations climaxed at the 6th day following ligation. Renal, activities of aldolase (ALD), lactic dehydrogenase (LDH), isocitric dehydrogenase (ICDH), sorbitol dehydrogenase (SDH), and alkaline phosphatase (ALP), were lowered in CBDL rats. Further, microsomal Na,K-ATPase and Mg-ATPase and mitochondrial oxidative-phosphorylation were inhibited. In the liver from CBDL rats the activities of aspartate aminotransferase (AST), Mg-ATPase and ALP were elevated, while SDH, ALD, malic dehydrogenase (MDH), LDH, malic enzyme (ME) and Na,K-ATPase were lowered. Plasma enzymes, AST, ALP, MDH, LDH, ALD, acid phosphatase (ACP) and ICDH and the metabolites bile acids, bilirubin, creatinine and urea were elevated. Addition of bile acids or bilirubin at concentrations comparable to those found in the plasma of CBDL rats, to the reaction mixture of the various enzymes strongly inhibited most, particularly mitochondrial oxidative phosphorylation. High concentrations of these substances in the blood may explain the development of renal failure during liver disease and its reversibility when liver function returns to normal.
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PMID:Biochemical changes in liver, kidney and blood associated with common bile duct ligation. 378 11


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