Effect of green tea extract on Doxorubicin induced cardiovascular abnormalities: antioxidant action

Doxorubicin (DOX) induces oxidative stress leading to cardiovascular abnormalities. Green tea extract (GTE) is reported to possess antioxidant activity mainly by means of its polyphenolic constituent, catechins. Our study was aimed to find out the effect of GTE (100 mg/kg / day p.o. for 28 days) on DOX induced (3 mg/kg, IP on days 1, 7, 14, 21, 28) cardiovascular abnormalities in rat heart. DOX treatment led to significant increase in blood pressure, ST interval, serum levels of LDH, CK, SGOT, lipid peroxidation .The antioxidant enzymes such as super oxide dismutase, catalase and reduced-glutathione were decreased considerably in the heart of DOX treated rats as compared to the normal control. A combined treatment with GTE and DOX showed a considerable decrease in serum markers of cardiotoxicity such as LDH, CK, SGOT and lipid peroxides. There was significant increase in the activities of antioxidant enzymes and also showed improvement in hemodynamic parameters and ECG changes as compared to DOX treated animals. DOX treatment caused disorganization of myocardial tissue which was restored in animals treated with GTE along with DOX. Thus it can be concluded that GTE possesses an antioxidant activity and by virtue of this action it can protect the heart from DOX induced cardiovascular abnormalities.