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)

This paper reports a study of changes in red blood cell enzymes and some serum parameters during and after treatment of protein-calorie malnutrition. The red cell GSH levels were low during the crisis, together with the levels of GSSG:NADPH reductase, GSH:H2O2 peroxidase, aspartate aminotransferase and alanine aminotransferase. After treatment the levels of all these enzymes increased significantly to normal values. Of the serum parameters investigated, significant reduction in the activity of the enzymes cholinesterase, catecholamine oxidase, total proteins, albumin, urea and electrolytes were obvious, and returned to normal values after treatment. Ceruloplasmin activity remained low even after three weeks' treatment and could not be related to copper levels. The results are discussed in relation to anemia and liver damage that may accompany the syndrome.
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PMID:Protein-calorie malnutrition: a study of red blood cell and serum enzymes during and after crisis. 82 Apr 94

Wistar rats received an hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, a halogenated pyrrole designated PD 123244-15, orally by gavage for 14 days at 10, 50, 150, 300, and 600 mg/kg. Doses of 150-600 mg/kg caused death and marked systemic toxicity involving stomach, esophagus, liver, gonads, lymphoid tissues, and skeletal muscle. Histopathologic findings included hyperkeratosis in esophagus and forestomach, increased hepatic mitotic activity, ovarian follicular necrosis, testicular atrophy and arrested spermatogenesis, and skeletal muscle necrosis and regeneration. Elevated serum aspartate aminotransferase correlated with muscle necrosis and hepatocellular damage. Marked systemic effects associated with high plasma concentrations were consistent with toxicity defined for other HMG-CoA reductase inhibitors, with the exception of pathologic alterations in the esophagus and ovaries. Direct mucosal irritation may have contributed to forestomach and esophageal lesions induced by this halogenated pyrrole.
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PMID:Subacute toxicity of a halogenated pyrrole hydroxymethylglutaryl-coenzyme A reductase inhibitor in Wistar rats. 130 25

Since fumarate and nitrate are not usually available in the oral ecosystem, it was investigated whether aspartate and asparagine could be used as alternative electron acceptors by Wolinella recta, which is strictly dependent on a respiratory metabolism with formate or H2 as electron donors. Both aspartate and asparagine were indeed shown to support growth of W. recta with formate as electron donor. Fermentative growth with aspartate alone was not possible. Succinate was the major end-product and was formed in equimolar quantities with respect to the amount of formate consumed. The consumption of aspartate and asparagine, on a molar basis, was 10-30% higher than that of formate. Cell-free extracts were prepared from cells grown with formate + fumarate, formate + aspartate, formate + asparagine, and formate + fumarate + aspartate. All these extracts contained high activities of asparaginase, aspartate ammonia-lyase and fumarate-reductase, but no significant activity of aspartate aminotransferase was detected, indicating that fumarate was synthesized directly from aspartate and subsequently reduced to succinate. Based on these results it seems likely that aspartate and asparagine can serve as natural electron acceptors for W. recta in periodontal lesions in which proteolytic bacteria abound.
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PMID:Aspartate and asparagine as electron acceptors for Wolinella recta. 194 91

A method for the purification of chicken liver soluble aspartate aminotransferase, lactate dehydrogenase free, is proposed. The preparation, which contained a mixture of the five molecular forms of the enzyme, showed a 120-fold increase in specific activity, with respect to the initial homogenates. Differences in Km(2-oxoglutarate) and saturating concentrations among solutions of purified enzyme and soluble fraction were due to the 2-oxoglutarate reductase activity of lactate dehydrogenase.
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PMID:Modification of the kinetic parameters of chicken liver cytoplasmic aspartate aminotransferase by lactate dehydrogenase. 405 24

1. In order to assess the effects of oestrogens on the metabolism of tryptophan and vitamin B6, ovariectomized rats have been maintained on diets providing known amounts of tryptophan, nicotinamide and vitamin B6. They received oestrone sulphate, 210 micrograms/kg body-wt per d, either incorporated in the diet for 8 weeks, or by daily intraperitoneal injection for periods of 1-3 d. 2. Oestrone sulphate administration caused a slight reduction in the concentration of pyridoxal phosphate in plasma. It had no effect on the concentration of pyridoxal phosphate in liver or kidney, the urinary excretion of 4-pyridoxic acid, the activation of erythrocyte aspartate aminotransferase (L-aspartate:2-oxo-glutarate aminotransferase, EC 2. 6. 1. 1) by incubation with added pyridoxal phosphate, or the activity of pyridoxal oxidase (aldehyde:oxygen oxido-reductase, EC 1.2.3.1) in the liver. 3. Oestrone sulphate administration caused an increase in the urinary excretion of kynurenine and a reduction in the activity of liver kynureninase (L-kynurenine hydrolase, EC 3.7.1.3). It had no effect on the urinary excretion of N1-methyl nicotinamide or the concentrations of nicotinamide nucleotides in blood, liver or kidney. 4. There was a considerable excess of the apoenzyme of kynureninase in the liver. Incubation of liver homogenates with added pyridoxal phosphate led to a 4- to 5-fold increase in activity. 5. We conclude that there is no evidence of any significant effect of oestrogens on vitamin B6. It is suggested that abnormalities of tryptophan metabolism in women receiving oestrogens, which have been widely attributed to drug-induced vitamin B6 depletion, can be accounted for by inhibition of kynureninase by oestrogen metabolites.
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PMID:Effects of oestrogen administration on vitamin B6 and tryptophan metabolism in the rat. 628 3

The coexistence of hypercholesterolemia and hypertension often requires concomitant drug treatments. Thus, it is interesting to evaluate the efficacy, safety, and tolerability of the new lipid-lowering agent fluvastatin, a 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA)-reductase inhibitor, in patients receiving concomitant antihypertensive/cardiovascular drug treatments. A retrospective analysis was based on data from controlled clinical trials in which 1815 patients were treated with fluvastatin and 783 patients received placebo. The daily dose of fluvastatin was > or = 20 mg. At least one of the following drug treatments was taken by 445 of the fluvastatin-treated patients (24.5%) and 181 of those receiving placebo (23.1%): beta-adrenergic-receptor blockers (fluvastatin: n = 182; placebo: n = 84); diuretics (fluvastatin: n = 168; placebo: n = 72); calcium antagonists (fluvastatin: n = 161; placebo: n = 69); and angiotensin-converting enzyme (ACE) inhibitors (fluvastatin: n = 101; placebo: n = 30). The majority of patients received monotherapy with one of the above-mentioned antihypertensive agents (fluvastatin: 69%; placebo: 65%). The efficacy of fluvastatin in modifying low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol and triglyceride levels was not consistently different in patients taking a given antihypertensive compared with the overall group and the patients not taking the antihypertensive agent. In patients taking fluvastatin and antihypertensives, confirmed (measured at two consecutive occasions) increases more than three times the upper limit of normal in aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) occurred in only two patients. One case involved the concomitant use of a beta-blocker (ASAT and ALAT) and the other a diuretic (ALAT).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Safety and tolerability of fluvastatin with concomitant use of antihypertensive agents. An analysis of a clinical trial database. 790 74

The concurrence of hypertension and hypercholesterolemia leads to the clinical need to lower lipids in hypertensive patients. Thus, it is interesting to evaluate the efficacy and safety of fluvastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA)-reductase inhibitor, in such a patient population. A retrospective analysis of the clinical efficacy and safety of fluvastatin was based on the data from 1815 patients who received fluvastatin at daily doses of > or = 20 mg compared with 783 patients taking placebo. The results showed that 332 (18.3%) of the fluvastatin-treated and 124 (15.8%) of the placebo-treated patients were identified as having hypertension. The percentage change from baseline of low-density lipoprotein cholesterol (LDL-C) in hypertensive patients taking fluvastatin at doses of 20 and 40 mg/day was -20% and -26%, respectively (placebo: 1.4%), and did not differ from the response in non-hypertensive patients. Increases in high-density lipoprotein cholesterol (HDL-C) as well as decreases in triglycerides with fluvastatin were not consistently different between hypertensive and non-hypertensive patients. Irrespective of the presence or absence of hypertension, confirmed (measured on two consecutive occasions) increases > three times the upper limit of normal in aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) were observed in three (0.2%) and 12 (0.7%) patients, respectively. With placebo, ALAT was increased in two patients (0.2%). The incidence of notable increases more than 10 times the upper limit of normal in creatine kinase was similar with fluvastatin compared with placebo (0.3% in both).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Efficacy and safety of fluvastatin in hypertensive patients. An analysis of a clinical trial database. 829 42

Fluvastatin, a new synthetic inhibitor of HMGCoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase, has been studied in several models to examine its effects when used in combination with other lipid-modifying agents such as derivatives of fibric acid (bezafibrate), resins (cholestyramine), and niacin. The combination of fluvastatin with bezafibrate has been studied in a double-blind trial involving patients with well-documented familial hypercholesterolaemia. Fluvastatin 40 mg/day, combined with either bezafibrate 400 mg/day or cholestyramine 8 g/day, resulted in reductions in levels of low-density lipoprotein cholesterol (LDL-C), these being indistinguishable between the groups; however, significantly greater increases in levels of high-density lipoprotein cholesterol (21.3%) and reductions in levels of triglycerides (25.1%) were seen with the fluvastatin-bezafibrate combination. No notable increases were seen in levels of serum creatine kinase, aspartate aminotransferase, or alanine aminotransferase, and no cases of myopathy were observed. In a study model that examined low-dose combinations of fluvastatin with cholestyramine, reductions in levels of LDL-C of 15.8% and 19.3% were seen with fluvastatin 10 mg and 20 mg, respectively. After an 8-week interval in which a daily dosage of cholestyramine 8 g was added, from baseline, reductions of 26.3% in the 10 mg fluvastatin-cholestyramine group and 31.2% in the 20 mg fluvastatin-cholestyramine group were observed, whereas the placebo-cholestyramine group displayed a reduction of 14.9%. Doubling the resin dosage to 16 g/day for the final 8 weeks of the study provided little additional benefit. Myotoxicity has been observed when lovastatin is coadministered with niacin, and so the combination of niacin with fluvastatin has also been studied to examine the possibility of this effect occurring. Patients were randomised to either fluvastatin 20 mg or placebo for 6 weeks, after which time open-label niacin was administered to all patients and titrated to a final dosage of 3 g/day. After 6 weeks, fluvastatin produced a 20.8% reduction in LDL-C levels from baseline. When combined with niacin, a 43.7% reduction was noted at the week 15 endpoint, against the 26.5% reduction seen with niacin monotherapy. The combination was well tolerated, with no reports of myopathy or of significant elevations in creatine kinase or liver transaminase levels. Combinations of fluvastatin with a variety of other agents have been shown to have significant effects on lipid profiles, with no evidence to date of clinically remarkable safety findings. Thus, the use of combination therapies may result in optimal management of patients with moderately severe hypercholesterolaemia and mixed dyslipidaemic profiles.
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PMID:Fluvastatin in combination with other lipid-lowering agents. 1949 70

The toxicity of atorvastatin (AT), an inhibitor of hydroxymethylglutaryl-coenzyme A reductase (HMG), was evaluated in beagle dogs. In 4 studies [2-wk rising dose (daily increasing doses for 1 wk; maintenance for 1 wk), 12-wk rising dose (daily dosing with weekly increases in dose), 2-wk toxicity (daily dosing for 2 wk; 3 dose levels), 13-wk toxicity (daily dosing for 13 wk; 3 dose levels)], dogs received up to 400 mg/kg orally. Doses of 180 mg/kg induced moribundity, necessitating euthanasia. Weight losses up to 26% were seen at doses > or = 150 mg/kg. Decreases in cholesterol levels were dose-related. Alanine and/or aspartate aminotransferase were increased at doses > or = 80 mg/kg; alkaline phosphatase was increased at doses > or = 150 mg/kg. Histopathologic findings were seen at > or = 150 mg/kg and included hepatocellular eosinophilia related to increased smooth endoplasmic reticulum and cholangiohepatitis and cholecystitis at 150 mg/kg in the 2-wk toxicity study; hepatocellular degeneration, centrilobular bridging, cholecystitis, hemorrhage in gallbladder and brain, demyelination of optic nerve, and skeletal muscle necrosis at > or = 280 mg/kg in the 12-wk rising dose study; and erosion and hemorrhage in large intestine, hepatocellular degeneration and necrosis, and inflammation and necrosis of gallbladder epithelium at 320 mg/kg in the 2-wk rising dose study. Doses up to 80 mg/kg for 13 wk did not induce histopathologic lesions in examined organs. AT effectively lowered serum cholesterol in normal lipidemic dogs. Toxicity at AT in dogs was similar to that with other inhibitors of HMG except that lenticular changes were not seen, significant hepatic, testicular, or neurological toxicity was associated only with high doses at AT, and skeletal muscle changes similar to those described in rats and rabbits were identified.
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PMID:Subchronic toxicity of atorvastatin, a hydroxymethylglutaryl-coenzyme A reductase inhibitor, in beagle dogs. 886 88

We found that NADPH-dependent ubiquinone reductase (NADPH-UQ reductase) in rat liver cytosol reduces ubiquinone (UQ) to ubiquinol (UQH2) in lipid membranes and consequently inhibits lipid peroxidation [Takahashi T., et al., Biochem. J., 309, 883-890 (1995)]. Here we examined whether or not this UQH2-regenerating system functions as a cellular antioxidant defense in animals. Rats were given UQ-10 for 2 weeks, and were then exposed to carbon tetrachloride (CCl4). The UQ-10 supplement increased only in the NADPH-UQ reductase and the UQH2-10 pool of rat liver without any appreciable change in the levels of other antioxidant factors. On the other hand, CCl4 markedly increased plasma aspartate aminotransferase and alanine aminotransferase, liver weight and thiobarbituric acid reacting substances formation, which are indicators of CCl4-hepatitis, and it decreased the liver levels of L-ascorbic acid, reduced form of glutathione (GSH), alpha-tocopherol, NADPH-UQ reductase and glutathione S-transferase. However, all the above indicators of CCl4-induced hepatitis were significantly improved in rats given UQ-10. Furthermore, alpha-tocopherol, but neither L-ascorbic acid nor GSH, was significantly saved. UQ-10 supplement also was recovered glutathione S-transferase and NADPH-UQ reductase activities slightly. These results indicated that UQ-10 given to rats increased the cellular UQH2-10 pool and cytosolic NADPH-UQ reductase activity in their livers, resulting in the inhibition of lipid peroxidation in the biomembranes, and consequently protected the rats from the CCl4-hepatotoxicity.
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PMID:Cellular antioxidant defense by a ubiquinol-regenerating system coupled with cytosolic NADPH-dependent ubiquinone reductase: protective effect against carbon tetrachloride-induced hepatotoxicity in the rat. 887 5


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