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)

The effect of variable doses of ethanol on plasma lecithin: cholesterol acyltransferase (LCAT) activity was examined in male, atherosclerosis-susceptible squirrel monkeys over a 12-month period. Primates were divided into three groups: 1) Controls fed isocaloric liquid diet; 2) Low Ethanol monkeys given liquid diet with vodka substituted isocalorically for carbohydrate at 12% of calories; and 3) High Ethanol animals fed diet plus vodka at 24% of calories. There were no significant differences between the treatments in serum glutamate oxaloacetate transaminase (SGOT), a measure of liver function. However, plasma LCAT activity (% esterification/min) measured in vitro was significantly reduced in High Ethanol monkeys while cholesterol esterification was elevated in the Low Ethanol group and intermediate in Controls. Similarly, the in vivo appearance of radiolabeled cholesteryl ester in high density lipoproteins (HDL) following the intravenous injection of 3H mevalonolactone was highest in the Low Ethanol primates, intermediate in Controls and significantly lower in monkeys fed the high alcohol diet. In vitro measurement of LCAT enzyme efficiency was similar for the three groups while substrate efficiency was lower in the High Ethanol treatment. Although LCAT activator (apoprotein A-I) was not markedly altered by dietary ethanol and the concentration of LCAT substrates (HDL free cholesterol and phosphatidyl choline) was significantly elevated in the High Ethanol group, subtle modifications in substrate-product composition may account for the observed reduction in cholesterol esterification. These include potential substrate and/or product LCAT inhibition resulting from increased concentrations of plasma free cholesterol, HDL lysophosphatidyl choline, and higher HDL2/HDL3 subfraction ratios, as well as alterations in HDL phospholipid fatty acid profiles in the High Ethanol group. Results from this study provide the first evidence of an anomalous enhancement in LCAT activity in nonhuman primates fed ethanol at 12% of calories and a marked depression in cholesterol esterification at the 24% dose which may be due to substrate alterations and product inhibition prior to overt biochemical evidence of liver dysfunction.
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PMID:Effect of ethanol on lecithin:cholesterol acyltransferase (LCAT) activity. 399 6

Male squirrel monkeys fed ethanol at variable doses were used to assess whether alcohol enhances de novo synthesis of high density lipoprotein (HDL) cholesterol in vivo. Monkeys were divided into three groups: 1) Controls fed isocaloric liquid diet; 2) Low Ethanol monkeys fed liquid diet with vodka substituted isocalorically for carbohydrate at 12% of calories; and 3) High Ethanol animals fed diet plus vodka at 24% of calories. High Ethanol primates had significantly higher levels of HDL nonesterified cholesterol than Control and Low Ethanol animals while serum glutamate oxaloacetate transaminase was similar for the three treatments. There were no significant differences between the groups in HDL cholesteryl ester mass or specific activity following intravenous injection of labeled mevalonolactone. By contrast, High Ethanol monkeys had significantly greater HDL nonesterified cholesterol specific activity with approximately 60% of the radioactivity distributed in the HDL3 subfraction. This report provides the first experimental evidence that ethanol at 24% of calories induces elevations in HDL cholesterol in primates through enhanced de novo synthesis without adverse effects on liver function.
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PMID:Ethanol enhances de novo synthesis of high density lipoprotein cholesterol. 646 61

This study compared the efficacy and safety of a once-a-night, time-release niacin formulation, Niaspan (Kos Pharmaceuticals, Miami Lakes, FL), with plain niacin and placebo for the treatment of primary hypercholesterolemia. The study was conducted in nine academic lipid research clinics in a randomized, double-blind design. Niaspan 1.5 g at bedtime was compared with plain niacin 1.5 g/d after 8 weeks and 3.0 g/d after 16 weeks in divided doses and with placebo. A total of 223 hypercholesterolemic adult men and women participated. Compared with placebo at 8 weeks, Niaspan versus plain niacin at 1.5 g/d showed comparable efficacy, comparably lowering total cholesterol (C) (8%/8%), triglycerides (16%/18%), low-density lipoprotein (LDL)-C (12%/12%), apolipoprotein (apo B) (12%/12%), apo E (9%/7%), and lipoprotein(a) [Lp(a)] (15%/11%), and raising high-density lipoprotein (HDL)-C (20%/17%), HDL2-C (37%/33%), HDL3-C (17%/16%), and apo A-I (8%/6%) (P < or = .05 in all instances). After 16 weeks, the Niaspan effect on LDL-C and triglyceride was unchanged while the plain niacin effect approximately doubled. At equal doses of 1.5 g/d of Niapan versus plain niacin, respectively, AST increased 5.0% versus 4.8% (difference not significant [NS]), fasting plasma glucose increased 4.8% versus 4.5% (NS), and uric acid concentrations increased less, 6% versus 16% (P=.0001). Flushing events were more frequent with plain niacin versus Niaspan (1,905 v 576, P < .001). Flushing severity was slightly greater with Niaspan, but still well tolerated. In conclusion, Niaspan 1.5 g hour of sleep (hs) has comparable efficacy, a lower incidence of flushing, a lesser uric acid rise, and an equivalent hepatic enzyme effect than 500 mg thrice-daily plain niacin in hyperlipidemic subjects. Niaspan may be an equivalent or better alternative to plain niacin at moderate doses in the management of hyperlipidemia.
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PMID:Equivalent efficacy of a time-release form of niacin (Niaspan) given once-a-night versus plain niacin in the management of hyperlipidemia. 975 Dec 39

Ten years' experience of treatment with the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor simvastatin in 45 hypercholesterolemic high-risk patients is reported. All patients started with 20 mg simvastatin/day. The simvastatin dose was increased to 40 mg in 22 patients. Fourteen patients needed further addition of cholestyramine. Simvastatin reduced plasma cholesterol by 33% after 1 month and was further reduced after adjustment of the lipid-lowering treatment. The mean reduction in plasma cholesterol varied between 30% and 35% in 2 to 10 years. Low-density lipoprotein cholesterol demonstrated mean reductions of 34% to 42%. Mean plasma triglycerides were reduced by 26% after 1 month and by 1% to 19% the following years. High-density lipoprotein (HDL) cholesterol increased initially by 8% and remained elevated at 7% to 11% during the first 6 years, but then dropped slightly below baseline. HDL2 cholesterol increased by 9% to 25% the first 6 years and then decreased. HDL3 cholesterol showed a persistent elevation during simvastatin treatment. About half of the subjects had minor transient but clinical insignificant increases in creatine kinase. No cases of myopathy were seen. Mean serum aspartate aminotransferase and alanine aminotransferase increased significantly but within the normal ranges during the 10 years. The tolerability and compliance of simvastatin treatment was excellent as judged from patients' reports and from analyses of low-density lipoprotein cholesterol. This 10-year study demonstrates that simvastatin is an effective and safe drug with excellent tolerability with only few minor side effects, and causes a pronounced and persistent cholesterol-lowering effect during long-term treatment of hypercholesterolemic patients at risk.
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PMID:Efficacy and safety of simvastatin for high-risk hypercholesterolemia. 1019 May 17

This randomized, double-blind, placebo-controlled crossover study was performed in 67 patients of both sexes aged 20 to 78 years with moderate hypercholesterolemia to investigate the antilipemic efficacy and tolerability of food supplement policosanol--a mixture of aliphatic primary alcohols from rice (Oryza sp.). After a 8-week run-in period in which patients were placed on therapeutic lifestyle changes, in particular cholesterol-lowering diet, they were randomly assigned to receive policosanol 10 mg capsules or placebo capsules once daily with the evening meal for 8 weeks. During next 8 weeks those receiving policosanol during the first 8 weeks, received placebo and those taking placebo during the first 8 weeks, received policosanol. Total cholesterol (C), LDL-C, HDL-C, HDL2-C, HDL3-C, triglycerides, oxidized LDL, apoproteins A I and B and lipoprotein (a) as well as AST, ALT, GGT, CK, blood glucose and bilirubin were determined before the treatment, after the first part of the study i.e. after the first 8 weeks and at the end of the study, i.e after the second 8 weeks. Policosanol significantly reduced plasma total cholesterol and increased apoprotein A I but did not change plasma triglycerides, HDL-C, HDL2-C, HDL3-C, LDL-C, oxidized LDL, Lp (a) and apoproteinS. It was well tolerated, with no drug-related effects on safety parameters such as serum aminotransferases, blood glucose, bilirubin, and CK, neither did it cause any clinical adverse reactions.
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PMID:[A randomized, double-blind, placebo-controlled study of the antilipemic efficacy and tolerability of food supplement policosanol in patients with moderate hypercholesterolemia]. 1658 32