Effectiveness of flavonoid-rich leaf extract of Acalypha indica in reversing experimental myocardial ischemia: biochemical and histopathological evidence.

OBJECTIVE

In this study, we investigated the antimyocardial ischemic effects of flavonoid-rich methanolic leaf extract of Acalypha indica (AIE).

METHODS

An animal model of myocardial ischemic injury was induced by isoproterenol (ISO) in adult rats. Albino Wistar rats were pretreated with the AIE (100 and 200 mg/kg body weight orally) for 30 d followed by ISO (85 mg/kg subcutaneously) at an interval of 24 h for 2 d. At the end of the experimental period (12 h after the second dose of ISO injection), rats were sacrificed by anaesthetization with an intramuscular injection of ketamine hydrochloride (24 mg/kg). To ensure anti-ischemic potential of AIE, the plasma lipids such as total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), free fatty acids (FFA), phospholipids (PL), myocardial lipids and hepatic lipids (TC, TG, FFA and PL) were estimated. Histopathology of heart tissue was also examined.

RESULTS

Administration of AIE maintained the levels of plasma lipids in all the treatment groups (100 and 200 mg/kg) when compared with the ISO-injected model rats. Histopathological examination of heart tissue of ISO-administered model rat showed myofiber loss, extensive subendocardial necrosis, infiltration of inflammatory cells, marked myocellular edema and vacuolar degeneration. However, pretreatment with AIE at 200 mg/kg showed predominantly normal myocardium structure with myofibers appeared and no inflammatory cell infiltration, edema and necrosis.

CONCLUSIONS

The biochemical and histological evidence from this study shows that AIE is protective against ISO-induced myocardial ischemia.