Antilipoperoxidative and membrane stabilizing effect of diosgenin, in experimentally induced myocardial infarction

Altered membrane integrity has been suggested as a major factor in the development of cellular injury during myocardial necrosis. The present study was designed to investigate the effect of diosgenin on lysosomal hydrolases, membrane-bound enzymes, and electrolytes during isoproterenol (ISO)-induced myocardial necrosis in rats. Animals were pretreated with DIOS (80 mg/kg) for a period of 35 days. Myocardial infarction was experimentally induced with ISO (85 mg/kg) twice at 24 h interval. Experimental myocardial infarction was evidenced with marked elevation of creatine kinase-MB (CK-MB) in serum with concomitant increase in lipid peroxidation (plasma thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HP)). Activity of lysosomal hydrolases (beta-glucuronidase, beta-N-acetyl glucosaminidase, beta-D-galactosidase, cathepsin D, and acid phosphatase) was found to be increased in serum and heart tissue of ISO-alone treated animals. DIOS (80 mg/kg) pretreated groups showed significant decrease in CK-MB, lipid peroxidation, and lysosomal hydrolases activity. The membrane-bound enzymes such as Ca2+-ATPase and Mg2+-ATPase activity was increased and Na+/K+-ATPase activity was decreased in the heart tissues of ISO-alone treated animals. These enzyme alterations lead to the change in the electrolytes content such as sodium, potassium, and calcium in the heart tissue. However, DIOS (80 mg/kg) pretreatment reversed the membrane-bound enzymes activity and thereby maintained the normal electrolyte concentration. These results suggest the protective action of diosgenin in ISO-induced myocardial infarction. The salubrious effect observed in this study might be due to the antioxidant and membrane stabilizing potential of diosgenin.