Cardioprotective Potential of Methanol Extract of Polygonum glabrum on Isoproterenol Induced Myocardial Necrosis in Rats

Aim: The aim of present study was to evaluate the cardioprotective efficacy of Polygonum glabrum on isoproterenol induced myocardial necrosis in rats. Methods: Experimental rats were treated orally with methanol extract of Polygonum glabrum at two doses (200 mg and 400 mg/kg) for 30 days. Isoproterenol (85 mg/kg, s.c.) was administered on 29 th and 30 th day to induce myocardial necrosis.  At the end of the experiment, serum cardiac marker enzymes [creatine kinase muscle brain (CK-MB), lactate dehydrogenase (LDH), serum glutamate oxaloacetate transaminase (SGOT)], serum glutamate pyruvate transaminase (SGPT) and total protein (TP) were estimated. Plasma total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), low density lipoprotein (LDL) and very low density lipoprotein (VLDL) levels were also recorded. Further, antioxidant parameters viz catalase (CAT), superoxide dismutase (SOD),  glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GRD) and malondialdehyde (MDA) levels were evaluated in heart tissue homogenate. Results: The results of the study indicated that, methanol extract of Polygonum glabrum showed greater cardioprotection by restoring the cardiac marker enzymes and attenuated the level of plasma lipid profiles along with an increase in HDL. Additionally, level of myocardial antioxidants significantly increased along with a reduction in the content of malondialdehyde. The cardioprotective effect was compared with propranolol     (10 mg/kg, oral) which was used as the standard. Histopathological findings revealed a decrease in the degree of necrosis and inflammation following pretreatment with Polygonum glabrum . Conclusion: The present investigation indicates that Polygonum glabrum could protect myocardium from isoproterenol induced necrosis.