Cardioprotective effect of juglone on isoproterenol-induced myocardial injury in SD rats

Aims: Therapeutic and/or preventive interventions using phytochemical constituents for ischemic heart disease have gained considerable attention worldwide, mainly due to its antioxidant activity. This study investigated the cardioprotective effect and possible mechanism of juglone, a major constituent of Walnut tree, using isoproterenol (ISO)-induced myocardial infarction (MI) model in rats.

Methodology: Rats were pretreated for five (5) days with juglone (1, 3 mg/kg, i.p) and atenolol (1 mg/kg, i.p) in separate experiments before inducing myocardial injury by the administration of ISO (80 mg/kg, s.c) at an interval of 24 hrs for 2 consecutive days (4^th and 5^th day). The cardioprotective effect of juglone was confirmed through lead II electrocardiograph (ECG), the cardiac biomarkers (ALT, AST, CPK, CK-MB, LDH and cTnI) and histopathological study.

Results: The results of our present study suggest that prior administration of juglone proved to be effective as a cardioprotective therapeutic agent in reducing the extent of myocardial damage (induced by ISO) by fortifying the myocardial cell membrane, heart tissue architecture, preventing inflammation, edema, necrosis and also by normalizing cardiac marker enzymes (AST, ALT, CPK, CK-MB, LDH and cTnI). Conclusion: In conclusion, this study has identified phytochemical constituents: juglone as a potential cardioprotective agent.