Histological Study of the Effect of Simvastatin on the Skeletal Muscle Fibers in Albino Rat and the Possible Protective Effect of Coenzyme Q 10

Background: Simvastatin is a lipid lowering agent. It reduces risk of mortality in persons with coronary heart disease. Some patients treated with simvastatin, have developed liver, kidney and skeletal muscle symptoms. Coenzyme Q10 has a significant antioxidant activity acting as a primary scavenger of free radicals and influences membrane stability in many tissues including skeletal muscle. Aim of the Work: Was to evaluate the effect of simvastatin drug on the histological structure of skeletal muscle fibers of adult male albino rats and the possible role of coenzyme Q10 (CoQ10) as a protective agent. Materials and Methods: 38 adult male albino rats were used and divided into three groups. Group I (control), group II included 10 rats treated with simvastatin for 4 and 12 weeks and group III included 10 rats treated with simvastatin and CoQ10 orally for 4 and 12 weeks. The gastrocnemius muscle was dissected and prepared for light and electron microscopic study. Results: In rats subjected to high therapeutic dose of simvastatin for 4 and 12 weeks, the gastrocnemius muscle showed variation in size, splitting and focal degeneration of myofibers as well as mononuclear cellular infiltration and increased deposition of collagen fibers in-between muscle fibers. EM revealed mitochondrial degeneration and dilatation of sarcoplasmic reticulum. Mitochondria were markedly accumulated between myofibrils and in subsarcolemmal space. Coadministration of coenzyme Q 10 with simvastatin for 4 and 12 weeks ameliorated most of the above mentioned histological changes in the animals used. Conclusion: Simvastatin drug caused skeletal muscle damage. Coenzyme Q 10 resulted in protection of the skeletal muscle fibers when given concomitantly with simvastatin.