Bacopa monniera protects rat heart against ischaemia–reperfusion injury: role of key apoptotic regulatory proteins and enzymes

Abstract

Rat isolated hearts were perfused in a Langendorff model to study the cardioprotective effects of Bacopa monniera, a medicinal herb used in the Indian system of medicine, on cardiomyocyte apoptosis and antioxidant status following ischaemia-reperfusion (I-R) injury. Forty-eight rats were randomly divided into four groups (12 in each group): sham group (no ischaemia-reperfusion injury), B. monniera control group (orally fed B. monniera at a dose of 75 mg/kg, for three weeks); ischaemia-reperfusion control group(subjected to ischaemia-reperfusion-induced myocardial injury) and B. monniera-treated group (same protocol as ischaemia-reperfusion control group except that rats also fed B. monniera). Post-ischaemic reperfusion injury resulted in significant cardiac necrosis, apoptosis, depression of heart rate, decline in antioxidant status and elevation in lipid peroxidation. Oral administration of B. monniera per se for three weeks to healthy rats caused augmentation of myocardial antioxidants, superoxide dismutase, catalase and glutathione, along with induction of heat shock protein 72 (HSP72). Ischaemia-reperfusion-induced biochemical and histopathological perturbations were significantly prevented by B. monniera (75 mg/kg) pre-treatment. Interestingly, B. monniera also restored the antioxidant network of the myocardium and reduced myocardial apoptosis, caspase 3 and Bax protein expression. Histopathological studies and myocardial creatine phosphokinase content further confirmed the cardioprotective effects of B. monniera (75 mg/kg) in the experimental model of ischaemia-reperfusion injury. The study provides scientific basis for the putative therapeutic effect of B. monniera in ischaemic heart disease.