LAUSR

Abstract Objectives Cardiovascular diseases (CVDs) are highly prevalent in various countries, and heart failure accounts for the majority of deaths. The present study focuses on determining the protective effect of ethanol extract of leaves of Tamarindus indica (TIEE) by in vitro and in vivo methods. Methods In vitro cardiotonic activity was determined using Langendorff’s heart perfusion assembly. In vivo studies were performed using Doxorubicin (1.5 mg/kg, i.p for seven days) induced cardiotoxicity in rats. These animals were simultaneously treated with the TIEE at a low dose (200 mg/kg, p.o), high dose (400 mg/kg, p.o) and standard drug Digoxin (100 μg/kg, p.o) for seven days. At the end of the study, various parameters like electrocardiogram (ECG) recording, serum levels of serum glutamic pyruvic transaminase (SGPT), lactate dehydrogenase (LDH), creatinine phosphokinase (CPK), and presence of cardiac troponin (cTnI) were determined. Isolated hearts were subjected to histopathological studies. Results The TIEE at a concentration of 60 μg/mL showed a significant cardiotonic effect in vitro that was evident by increased force of contraction, heart rate, and cardiac output. In vivo studies revealed that the TIEE decreased the prolongation of QT and RR interval of ECG, lowered the serum enzyme levels like LDH, CPK indicating cardiac protection, and the same was established by the absence of cTnI in blood. Histopathological examinations of heart tissue sections showed improved architecture in the treatment groups when compared with diseased groups. Conclusions The study revealed the cardioprotective activity of T. indica leaf extract by both in vitro and in vivo methods.