In vivo cardioprotective effect of withacoagulin (20β, 27-Dihydroxy-1-oxo-(22R)-witha-2, 5, 24-tetraenolide) in experimental myocardial infarction in albino rats.

The present study was designed to evaluate the in vivo effect of withacoagulin isolated from Withania coagulans fruits in preventing myocardial infarction in rats.  Effect of withacoagulin was compared with Vitamin E, a known cardioprotective antioxidant. Male albino rats (120–150 g) were divided into five experimental groups (n=8): Normal control, Toxic (isoprenaline) control, withacoagulin (25 mg/ kg) per se, Vitamin E control (100 mg/kg, p.o.) and withacoagulin treatment group (25 mg/kg; p.o.). After treatment of 28 days to the animals of withacoagulin and vitamin E group, the rats in the isoprenaline toxic control and withacoagulin/vitamin E treatment group were given isoprenaline (85 mg/kg; s.c.) on day 29 and day 30, at an interval of 24 hour to induce myocardial infarction. On day 31^st, the animals were euthanized using CO₂ chamber and hearts were removed for histopathological and biochemical studies. Biochemical assessment showed significant decrease (P<0.05) in glutathione level. Highly significant decrease (P<0.01) in the level of superoxide dismutase, catalase, creatinine phosphokinase and lactate dehydrogenase has been observed. A highly significant increase (P<0.01) in lipid peroxidation marker malonyldialdehyde level was observed in the hearts of isoprenaline control rat as compared to normal control rat. On histopathological examination, myocardial damage was further confirmed due to injected isoprenaline. Withacoagulin (25 mg/ kg) showed a strong cardioprotective effect in isoprenaline-induced myonecrosis in rat. Augmentation of endogenous antioxidants and maintenance of the myocardial antioxidant status may contribute to its cardioprotective effect.