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)

The activities of several enzymes functioning in different areas of fuel catabolism were measured under standardized conditions, using crude homogenates of sartorius and ventricular muscle from outbred guinea-pigs and rabbits indigenous to high or low altitude. The activities of sartorius and myocardium were found to reflect the metabolic patterns known to be associated with white and red muscle. Both species had right ventricular hypertrophy at high altitude. The enzyme activities in the high altitude guinea-pig were not significantly different from those in the sea level animals. In the high altitude rabbit, compared with the low altitude rabbit, the activities of glyceraldehyde-3-phosphate deydrogenase and phosphofructokinase were greater in both the sartorius and myocardium. In addition, mitochondrial glycerol-3-phosphate dehydrogenase activity was greater in the sartorius at high altitude, while aspartate aminotransferase and beta-hydroxyacylcoenzyme A dehydrogenase activities were greater in the myocardium at high altitude. Succinate dehydrogenase activity was comparable at the two altitudes for both tissues. There was a greater proportion of skeletal muscle type lactate dehydrogenase in the high altitude rabbit myocardium but no difference was found with the guinea-pig.
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PMID:Enzyme activities in red and white muscles of guinea-pigs and rabbits indigenous to high altitude. 12 53

The aim of the present study was to investigate whether the levels of the malate-aspartate and alpha-glycerophosphate shuttle enzymes in human skeletal muscle are affected by endurance training. The approach used was to compare six untrained and six endurance-trained subjects as well as through performing a longitudinal study of endurance training on eight untrained subjects. Biopsy samples were obtained from the lateral part of the quadriceps femoris muscle. The trained muscles were characterized by higher levels of oxidative enzymes (55%) as well as enhanced capillary supply (30%). In both the cross-sectional and longitudinal studies, the malate-aspartate shuttle enzyme levels were about 50% higher in the trained state (cytoplasmic malate dehydrogenase 36%, mitochondrial malate dehydrogenase 46%, cytoplasmic aspartate aminotransferase 52% and mitochondrial aspartate aminotransferase 48%). Contrary to this, the alpha-glycerophosphate shuttle enzyme levels did not differ significantly (cytoplasmic and mitochondrial glycerol-3-phosphate dehydrogenase: 10 and -4%, respectively). The activity ratios of the enzymes involved in respective shuttle did not differ significantly between the untrained and endurance-trained states. It is concluded that endurance training may induce increased levels of malate-aspartate shuttle enzymes in human skeletal muscle while the levels of the alpha-glycerophosphate shuttle enzymes are not affected. The study also includes results from several methodological experiments.
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PMID:Malate-aspartate and alpha-glycerophosphate shuttle enzyme levels in human skeletal muscle: methodological considerations and effect of endurance training. 349 92

In rats that received a low protein isocaloric diet (protein content of the diet: 8 instead of 20%) during fetal life and thereafter up to the time of sacrifice at 12-13 weeks of age, a low plasma insulin concentration, a decreased insulin content of isolated pancreatic islets, and an impaired secretory response of the islets to either D-glucose or the association of L-leucine and L-glutamine coincided, in islet homogenates, with a low activity of the mitochondrial glycerophosphate dehydrogenase and an abnormally high ratio between glutamate-alanine and glutamate-aspartate transaminase activities. Opposite enzymatic changes were found in liver extracts of the same rats. No obvious change in these hormonal, secretory, and enzymatic variables were observed when the period of protein deficiency was restricted to fetal life. These findings support the view that, in protein malnutrition, an impaired activity of pancreatic B-cell mitochondrial glycerophosphate dehydrogenase contributes, possibly in association with other enzymatic anomalies, to the perturbation of islet function.
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PMID:Impaired activity of rat pancreatic islet mitochondrial glycerophosphate dehydrogenase in protein malnutrition. 775 Apr 86