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)

This randomized, double-blind, multicenter, diet-and-placebo-controlled study was designed to clarify the dose-response relationship of lovastatin therapy to lipid-modifying efficacy and drug-related adverse events. Exclusion criteria were minimized so that study patients were representative of the majority of patients with moderate hypercholesterolemia seen in medical practice. After 6 weeks on the American Heart Association Step 1 Diet, a total of 8,245 patients were randomly assigned to 48 weeks of treatment with diet and placebo or lovastatin at dosages of 20 or 40 mg once a day or 20 or 40 mg twice a day. All adverse events were monitored, with particular attention to evaluation of liver and muscle. Liver transaminase elevations suggestive of possible hepatotoxicity, defined as successive elevations in either aspartate transaminase or alanine aminotransferase greater than 3 times the upper limit of normal, occurred in equal numbers of placebo and lovastatin 20 mg/day treated patients (0.1%). The frequencies were higher in lovastatin 40 mg/day and 80 mg/day patient groups (0.9 and 1.5%, respectively). No patient was diagnosed as having clinically symptomatic hepatic dysfunction. Creatinine kinase (CK) elevations above the upper limit of normal occurred frequently in placebo- (29%), as well as lovastatin-treated patients (29-35%), and muscle symptoms were reported with similar frequency in all groups (7-9%). The combination of muscle symptoms with marked CK elevations (greater than 10 times the upper limit of normal) was seen in only five patients: one in a 40 mg/day dose group and four in the 80 mg/day dose group. No patient developed rhabdomyolysis. The incidence of clinical and laboratory adverse events requiring discontinuation was 6% for the placebo group and from 7% (20 mg/day) to 9% (80 mg/day) for lovastatin treatment groups. No new types of adverse experiences related to lovastatin treatment were reported. Lovastatin, as an adjunct to diet for the reduction of elevated LDL cholesterol, was generally very well tolerated.
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PMID:Expanded clinical evaluation of lovastatin (EXCEL) study results: IV. Additional perspectives on the tolerability of lovastatin. 183 Oct 6

Pravastatin, lovastatin, and simvastatin, drugs which lower cholesterol by inhibiting 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, have been linked to skeletal myopathies in humans and rats. The myotoxicity of these three drugs was compared, after 48 hr exposure, in cultures of primary neonatal rat skeletal myotubes. Measurements included HMG CoA reductase activity ([14C]acetate incorporation into cholesterol), indicators of membrane damage (CPK, LDH, and AST), cell viability (mitochondrial dehydrogenase metabolism of MTT), protein synthesis ([3H]leucine incorporation), and energy status (ATP). All three drugs inhibited cholesterol synthesis to the same extent in rat hepatocytes (IC50s approximately 0.07 microM). Lovastatin- and simvastatin-induced inhibition of cholesterol synthesis in myotubes was unchanged compared to that of hepatocytes, but pravastatin was 85-fold less potent (IC50 = 5.9 microM). Protein synthesis and ATP levels were the most sensitive indicators of toxicity. Pravastatin (IC50 = 759 microM) was > 100-fold less inhibitory of protein synthesis than lovastatin (IC50 = 5.4 microM) or simvastatin (IC50 = 1.9 microM). Addition of mevalonic acid (the immediate product of the HMG CoA reductase reaction), as 100 microM mevalonic acid lactone, reversed the toxicity of all three drugs. Removal of serum for 24-72 hr did not alter the toxicity of any of the drugs compared to cultures containing 10% serum, suggesting that differences in protein binding did not account for the differences in toxicity of the drugs. These results indicate that pravastatin is less myotoxic than lovastatin or simvastatin in this in vitro system using neonatal rat skeletal muscle cells, and this differential toxicity is correlated with the selective decrease in inhibition of HMG CoA reductase by pravastatin in nonhepatic tissues.
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PMID:In vitro myotoxicity of the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, pravastatin, lovastatin, and simvastatin, using neonatal rat skeletal myocytes. 787 72

This randomized, double-blind study was undertaken to compare the efficacy and tolerability of policosanol (10 mg/day) and lovastatin (20 mg/day) in patients with hypercholesterolemia and noninsulin dependent diabetes mellitus. After 6 weeks on a lipid lowering diet, 53 patients were randomized to receive either policosanol or lovastatin tablets that were taken o.i.d. for 12 weeks under double-blind conditions. Both groups were similar at randomization. Policosanol significantly (p < 0.001) lowered low-density lipoprotein (LDL)-cholesterol (20.4%), total cholesterol (14.2%) and the ratio of LDL-cholesterol to high-density lipoprotein (HDL)-cholesterol (23.7%). Lovastatin significantly (p < 0.01) lowered LDL-cholesterol (16.8%), total cholesterol (14.0%) and the ratio (p < 0.05) of LDL-cholesterol to HDL-cholesterol (14.9%). Triglyceride levels did not significantly change after therapy. Policosanol, but not lovastatin, significantly increased (p < 0.01) levels of HDL-cholesterol (7.5%). Comparison between groups showed that changes in HDL-cholesterol induced by policosanol were significantly greater (p < 0.01) than those induced by lovastatin. Both treatments were safe and well tolerated. Lovastatin moderately but significantly (p < 0.05) increased levels of aspartate aminotransferase, creatine phosphokinase and alkaline phosphatase. Adverse reactions were more frequent in the lovastatin group (p < 0.01) than in the policosanol group. In conclusion, policosanol administered at 10 mg/day produces more advantageous changes in HDL-cholesterol and has a better safety and tolerability profile than lovastatin 20 mg/day.
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PMID:Comparative study of the efficacy and tolerability of policosanol and lovastatin in patients with hypercholesterolemia and noninsulin dependent diabetes mellitus. 1093 29

A case of colchicine-induced rhabdomyolysis is reported. A 48 year old African-American male with history of hypertension and chronic gout on colchicine 0.6 mg daily presented with symptoms of a community acquired pneumonia. The patient was started on 500 mg of clarithromycin orally twice daily and represented to the emergency room after 3 days complaining of severe muscle pain. His liver panel showed elevations in the serum aminotransferases; AST 513 mU/ml (nl 15-41) and ALT 182 mU/ml (nl 17-63). His complete blood count showed an elevated white blood cell count of 18,800/ml (nl 4,000-10,000/ml). Urine analysis was positive for myoglobin with no red cells present. Serum creatine kinase (CK) was 22,996 mU/ml (nl 31-221) with a normal troponin I 0.18 (nl <0.4).Investigations confirmed the presence of rhabdomyolysis and discontinuation of colchicine and clarithromycin resulted in resolution of clinical and biochemical features of rhabdomyolysis. By hospital day four, his muscle soreness had improved markedly. His serum CK improved to 3,389 mU/ml (nl 31-221 mU/ml) and serum creatinine improved to 1.5 mg/dl (nl 0.8-1.2). On hospital day five, the patient was discharged on oral anti-hypertensive medication and a ten-day course of doxycycline. Metabolism of colchicine by the cytochrome P450 3A4 system has been previously described, but this is the first published report of colchicine associated rhabdomyolysis secondary to drug metabolism interactions with an antibiotic. A review of medications that are metabolized via the cytochrome 3A4 and A-SLAVED-LIVER (Amiodarone, Simvastatin, Lovastatin, Atorvastatin, Verapamil, Erythromycin, Diltiazem, cLarithromycin, Itraconazole, Voriconazole, colchicinE, Ritonavir) pneumonic was established.
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PMID:Short term treatment with clarithromycin resulting in colchicine-induced rhabdomyolysis. 2541 92

The effects of polarized-light therapy (PLT) on high-cholesterol diet (HCD)-induced hypercholesterolemia and atherosclerosis were investigated in comparison with that of lovastatin in rabbits. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 1% cholesterol in diet for 2 weeks and maintained with 0.5% cholesterol for 6 weeks, followed by normal diet for 2 weeks for recovery. Lovastatin (0.002% in diet) or daily 5-min or 20-min PLT on the outside surface of ears was started 2 weeks after induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaques formation covering 57.5% of the arterial walls. Lovastatin markedly reduced both the cholesterol and LDL, but the reducing effect (47.5%) on atheroma formation was relatively low. By comparison, 5-min PLT preferentially decreased LDL, rather than cholesterol, and thereby potentially reduced the atheroma area to 42.2%. Notably, 20-min PLT was superior to lovastatin in reducing both the cholesterol and LDL levels as well as the atheromatous plaque formation (26.4%). In contrast to the increases in blood alanine transaminase and aspartate transaminase following lovastatin treatment, PLT did not cause hepatotoxicity. In addition, PLT decreased platelets and hematocrit level. The results indicate that PLT attenuates atherosclerosis not only by lowering blood cholesterol and LDL levels, but also by improving blood flow without adverse effects. Therefore, it is suggested that PLT could be a safe alternative therapy for the improvement of hypercholesterolemia and atherosclerosis.
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PMID:Anti-hypercholesterolemic and anti-atherosclerotic effects of polarized-light therapy in rabbits fed a high-cholesterol diet. 2247 73