Potential interaction of green tea extract with hydrochlorothiazide against doxorubicin-induced myocardial damage

Treatment of ischemic hypertensive patients with hydrochlorothiazide can precipitate cardiac arrhythmias. Green tea, by virtue of its antioxidant potential, is responsible for cardio-protective activity.

The present study was under taken to evaluate the pharmacodynamic interaction of green tea extract with hydrochlorothiazide (HCTZ) against doxorubicin (DOX)-induced myocardial toxicity.

Rats were treated with high (500 mg/kg, p.o.) and low (100 mg/kg, p.o.) dose of green tea extract in alone and interactive groups for 28 days. Standard, high and low dose of interactive groups received hydrochlorothiazide (10 mg/kg, p.o.) for the last 7 days. Apart from normal controls, all other groups were subjected to DOX (3 mg/kg, i.p.) toxicity on Days 1, 7, 14, 21 and 28, and the effect of different treatments was evaluated by changes in electrocardiographic parameters, serum biomarkers and tissue antioxidant levels. Apart from that, lipid profile and histological studies were also carried out.

Compared with the DOX control group, both high and low dose of green tea exhibited a significant decrease in serum biomarkers and increase in tissue antioxidant levels. Green tea treatment was also responsible for significant improvement in ECG parameter, lipid profile and histological score. Incorporation of high and low dose of green tea with HCTZ exhibited significant protection compared with the HCTZ alone treated group.

The present findings clearly suggest that the green tea extract dose-dependently reduces DOX-induced myocardial toxicity. Green tea when combined with HCTZ can reduce the associated side-effects and exhibits myocardial protection.