Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027121 (myositis)
 4,538 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fibric acid derivatives (FADs) are a class of drugs that have been shown to reduce the production of very low-density lipoprotein (VLDL) while enhancing VLDL clearance due to the stimulation of lipoprotein lipase activity. The drugs can reduce plasma triglyceride levels while raising high-density lipoprotein (HDL) cholesterol levels. Their effects on low-density lipoprotein (LDL) cholesterol levels are less marked and more variable. There is evidence that oral gemfibrozil (Lopid, Parke-Davis, Morris Plains, NJ) can reduce the risk of serious coronary events, specifically in those patients who had elevations of both LDL cholesterol levels and total plasma triglyceride levels with lower HDL cholesterol levels. Newer FADs (bezafibrate, ciprofibrate, fenofibrate) have been shown to have greater efficacy in reducing LDL cholesterol than gemfibrozil but, in general, these drugs are not as effective as the other primary drugs used to lower LDL levels. The FADs are also used to treat adult patients with very high levels of triglycerides who have pancreatitis and whose disease cannot be managed with dietary therapy. The FADs are well tolerated, with dyspepsia and abdominal pain the most common adverse effects. A small risk of cholelithiasis exists with these drugs, and caution should be used when combining these drugs with HMG-CoA reductase inhibitors because the combination increases the incidence of hyperlipidemic myositis and rhabdomyolysis.
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PMID:Effects of gemfibrozil and other fibric acid derivatives on blood lipids and lipoproteins. 204 26

Hyperlipidemia is common in patients with glomerular proteinuria. It may contribute to atherosclerotic complications and accelerate glomerular damage. Early trials of the fibric acid derivative clofibrate led to a myositis syndrome causing many nephrologists to abandon attempts at treatment of nephrotic hyperlipidemia. Recent trials with lipid-lowering medications have been successful without major side effects. The bile acid sequestrants colestipol and cholestyramine bind bile acids in the gut and deplete the hepatic cholesterol pool, thus inducing LDL hepatocyte receptors. Recent studies showed a reduction of total cholesterol of 8-20% and LDL cholesterol of 19-31% without significant changes in HDL cholesterol. Probucol has reduced total cholesterol 23-30% and LDL cholesterol 23-25% in nephrotic patients. Although HDL cholesterol was reduced, the LDL/HDL ratio remains favorably changed. The fibric acid derivative gemfibrozil inhibits adipose lipolysis and enhances lipoprotein lipase activity thus decreasing LDL synthesis and increasing its removal. It caused a large decrease in triglycerides with a 13-15% decrease in total and LDL cholesterol in a recent trial. HDL cholesterol increased 18%. The HMG-CoA reductase inhibitors inhibit the rate-limiting step in cholesterol biosynthesis hence inducing an increase in LDL receptors on hepatocytes. Trials have shown decreases of 18-36% in total cholesterol and 18-47% in LDL cholesterol, while HDL cholesterol was either increased or unchanged. The use of lipid-lowering agents of several classes has been effective in ameliorating the progression of glomerular damage in a number of different models of glomerulosclerosis. Nevertheless, so far in humans lipid lowering drugs have not been established to have an effect on either the degree of proteinuria or the progression of glomerulosclerosis.
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PMID:Lipid-lowering agents in proteinuric diseases. 225 70

A procedure for the isolation and partial purification of three hydroxymethylglutaryl coenzyme A reductase phosphatases in their native high molecular weight form from rat liver microsomes is described for the first time. Reductase phosphatase Ex (Mr 90,000), IM (Mr 75,000), and IIM (Mr 180,000) were purified 132-, 55-, and 98-fold, respectively. Treatment with 80% ethanol irreversibly inactivated the three enzymes contrary to what is found for cytosolic reductase phosphatases. The three microsomal reductase phosphatases differ among themselves and with respect to the cytosolic reductase phosphatases in molecular weight, response to inhibitors, thermal stability, and optimum pH. Indirect evidence that these three proteins are phosphatases includes their inhibition by inhibitors of phosphatase activity, such as KF, Pi, and PPi. Direct evidence includes their ability to release 32P from highly radioactive homogeneous 32P-labeled HMG-CoA reductase, this dephosphorylation being concomitant with activation of HMG-CoA reductase. The three phosphatases dephosphorylate 32P-labeled phosphorylase a, but only reductase phosphatase IIM shows glycogen synthase phosphatase activity.
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PMID:Partial purification from rat liver microsomes of three native protein phosphatases with activity towards HMG-CoA reductase. 633 Feb 55

Fluvastatin sodium (Lescol; Sandoz) the first entirely synthetic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor studied, is structurally distinct from the other HMG-CoA reductase inhibitors currently available, all of which are fungal metabolites and analogues of compactin. Fluvastatin's distinct structure may be responsible for the biopharmaceutical properties that result in its low systemic exposure and, subsequently, low incidence of peripheral adverse events, such as headache and myositis. Fluvastatin is rapidly absorbed from the gastrointestinal tract; has a 30-minute half-life, the shortest of any currently available HMG-CoA reductase inhibitor (lovastatin, 15 hours; pravastatin, 2 hours; simvastatin, 15.6 hours); is highly selective for the liver, undergoing extensive first-pass metabolism; has no active circulating metabolites; and does not penetrate the blood-brain barrier, unlike lovastatin and simvastatin. The low systemic exposure suggests that the occurrence of peripheral adverse events, such as myositis, central nervous system effects, and drug-drug interactions, may be less than what is currently observed with other HMG-CoA reductase inhibitors. Neither niacin nor propranolol had an effect on fluvastatin plasma levels when combined with fluvastatin. In contrast to other HMG-CoA reductase inhibitors, fluvastatin in combination with niacin resulted in no instances of myositis or other serious adverse events. Although the interaction of fluvastatin with cholestyramine resulted in a lower rate and extent of fluvastatin bioavailability, this reduction had no impact on clinical efficacy. Fluvastatin administered to patients chronically receiving digoxin had no effect on the area under the curve (AUC) of digoxin compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Clinical implications of the biopharmaceutical properties of fluvastatin. 819 18

One of the major side-effects of the use of HMG CoA reductase inhibitors for the treatment of hypercholesterolemia is the development of myositis and, in some patients undergoing concomitant immunosuppressive treatment, the development of rhabdomyolysis. Experiments outlined in these studies demonstrate that inhibitors of HMG-CoA reductase activity which differ primary in the substitution of a methyl group for a hydroxyl group have differential effects on both cholesterol levels and cell viability in a striated muscle cell model, the mouse C2-C12 myoblast. Thus, concentrations as high as 200 microM of pravastatin had little effect on total cholesterol level while 25 microM of lovastatin decreased cellular cholesterol by over 90%. Simvastatin and lovastatin decreased viability of C2-C12 myoblasts by nearly 50% at concentrations as low as 1 and 5 microM, respectively, and decreased viability by almost 90% at 10 and 15 microM respectively. However, 300 microM of pravastatin decreased cell viability by less than 50%. The order of potency for the effects on cell viability wassimvastatin>lovastatin>>>pravastatin. The possible relationship between effects on cell viability and the development of myositis is discussed.
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PMID:Differential sensitivity of C2-C12 striated muscle cells to lovastatin and pravastatin. 857 54

Recently, a new class of lipid lowering agents [3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitors] was introduced into clinical practice. The use of these agents could lead to a secondary deficiency in carnitine, which may manifest clinically as a myalgia/myositis-a side effect that is occasionally seen with this class of drugs. In the present study, we examined the effect of an HMG-CoA reductase inhibitor (lovastatin) on serum and tissue levels of carnitine and carnitine acyltransferase activities in the rabbit. Rabbits (n = 6) were fed chow containing lovastatin (30 mg/d) for 16 wk. Blood was collected and tissues (liver, heart, and skeletal muscle) harvested at sacrifice. Free and total carnitine were measured in serum and tissues by a radioenzymatic method. Carnitine acetyltransferase and carnitine palmitoyltransferase (CPT) activities were determined and expressed relative to DNA. Serum free (24.0 +/- 2.6 vs. 29.4 +/- 3.1 microM) and total (35.1 +/- 4.7 vs. 52.8 +/- 8.8 microM) carnitine levels increased significantly with 16 wk of treatment. This increase in total carnitine was mainly due to an increase in the levels of serum acylcarnitine (12.7 +/- 3.1 vs 26.5 +/- 5.7 microM). Tissue levels of total carnitine were significantly decreased by the treatment. Carnitine acetyltransferase was unaffected by the treatment, whereas there was a significant increase in the activity of CPT in the liver and heart.
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PMID:The effects of 3-hydroxy-3-methylglutaryl-CoA reductase inhibition on tissue levels of carnitine and carnitine acyltransferase activity in the rabbit. 886 89

Initial trials hint that HMG-CoA reductase inhibitors may have a role in preventing or retarding the progression of AGAS. Whether the potential of HMG-CoA reductase inhibitors to prevent AGAS is due to their lipid-lowering effect, immunomodulating properties, or a combination of both is also not completely known at present. Further study is needed to fully identify their mode of preventing AGAS and, more important, to determine their usefulness and role in preventing AGAS, especially since concurrent HMG-CoA reductase inhibitor use with cyclosporine is not innocuous. Potential for a pharmacokinetic drug interaction, which results in an elevation of HMG-CoA reductase inhibitor concentrations, exists when these two agents are used together, thus increasing the potential for the HMG-CoA reductase inhibitor to cause musculoskeletal complications. When such combination therapy is used, the likelihood of this interaction can be reduced by prescribing the HMG-CoA reductase inhibitor conservatively--using the smallest effective dose and increasing the daily dosage slowly. Although the risk of musculoskeletal toxicity exists at any HMG-CoA reductase inhibitor dosage, most patients should be able to tolerate daily dosages of up to 20 mg of lovastatin, 10 mg of simvastatin, and 40 mg of pravastatin. Patients also need to be made aware of and monitored for musculoskeletal symptoms suggestive of myositis and/or myalgias. In addition, the avoidance of elevated cyclosporine concentrations and when practical, monitoring of HMG-CoA reductase inhibitor concentrations are recommended.
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PMID:The use of HMG-CoA reductase inhibitors to prevent accelerated graft atherosclerosis in heart transplant patients. 910 Oct 13

The use of lipid-altering drugs has been shown to reduce the progression of atherosclerotic lesions and reduce the risk of atherosclerotic events (such as myocardial infarction and stroke). In general, these lipid-altering drugs are well tolerated but there is the potential for drug interactions. For example, HMG-CoA reductase inhibitors may interact with macrolides, azalides, azole antifungals and cyclosporin. Resins (such as cholestyramine and colestipol) may impair the absorption of many concurrent medications. Fibrates have potential drug interactions with warfarin, furosemide (frusemide), oral hypoglycaemics and probenecid. Nicotinic acid (niacin) may have potential drug interactions with high dose aspirin (acetylsalicylic acid), uricosuric agents (such as sulfapyrazone) and alcohol (ethanol). Finally, probucol may have potential drug interactions with antidysrhythmics, tricyclic antidepressants and phenothiazines. In addition, lipid-altering drugs, used in combination, may have the potential for drug interactions, enhancing some of the risks of adverse effects, such as myositis and hepatotoxicity. Therefore, in order to use lipid-altering drugs in the most effective, and safest manner, it is important for the clinician to have an understanding of the mechanisms of potential drug interactions, which drug interactions may theoretically occur, and specifically, which spe cific drug interactions have already been described.
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PMID:Drug interactions of lipid-altering drugs. 982 49

Hyperlipidemia is an important cardiovascular risk factor. Lipid-lowering therapy has been shown to decrease morbidity and mortality in these patients. Combination therapy with a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor and a fibric-acid derivative has been reported to be more efficacious to reduce low-density lipoprotein (LDL) cholesterol and triglycerides but may be associated with an increased risk of myositis. The aim of this study was to investigate the efficacy and tolerability of fluvastatin, an HMG-CoA reductase inhibitor, alone and in combination with bezafibrate, a fibric-acid derivative. In a randomized controlled trial with 454 hypercholesterolemic patients (mean cholesterol, 8.6 +/- 1.6 mM), fluvastatin (20 mg/day) significantly lowered total plasma cholesterol levels (-12.5%; p < 0.0001 vs. placebo), LDL cholesterol (-14%; p < 0.0001), and triglycerides (-4%; p = 0.05). A small increase in high-density lipoprotein (HDL) cholesterol levels (3%, NS) also was observed. Combination therapy with fluvastatin and bezafibrate (400 mg/day) in 71 patients with persistent hypertriglyceridemia during treatment with the statin resulted in a more pronounced reduction in triglyceride (-47%; p < 0.0001) and total cholesterol levels (-15%; p < 0.0001) than did fluvastatin alone. Furthermore, the additional bezafibrate significantly increased HDL cholesterol (+5%; p < 0.001). No significant increases in creatine phosphokinase levels or in frequency of myalgia were observed. In summary, fluvastatin decreases both cholesterol and triglyceride levels. In patients with persistent hypertriglyceridemia, combination therapy with fluvastatin and bezafibrate may be safely used to lower triglyceride and cholesterol levels more efficiently.
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PMID:Efficacy and tolerability of fluvastatin and bezafibrate in patients with hyperlipidemia and persistently high triglyceride levels. 1071 Jan 19

Simvastatin belongs to a class of lipid-lowering drugs which completely inhibit 3-hydroxy-3-methylglutaryl co-enzyme A (HMG CoA) reductase. The commonest adverse effects of therapy with simvastatin HMG CoA reductase inhibitors are gastro-intestinal disturbance, myositis and myopathy. Rhabdomyolysis leading to renal failure has been reported, but it appears to be very rare, except in patients also receiving cyclosporin, nicotinic acid or gemfibrozil. Here we report the case of an elderly lady who was known to have chronic renal failure, but who developed rhabdomyolysis following simvastatin therapy. Her symptoms of muscle pain, fatigue, myoglobulinuria, oliguria and pulmonary oedema appeared 48 h after the first dose of simvastatin. Simvastatin was immediately stopped, and the patient was dialysed for 1 week. Her renal function improved and came back. We suggest that extreme care should be exercised in prescribing this drug, particularly for the elderly with renal impairment.
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PMID:Simvastatin-induced rhabdomyolysis in a patient with chronic renal failure. 1127 41


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