Liguzinediol improved the heart function and inhibited myocardial cell apoptosis in rats with heart failure

Aim: Liguzinediol is a novel derivative of ligustrazine isolated from the traditional Chinese medicine Chuanxiong (Ligusticum wallichii Franch), and produces significant positive inotropic effect in isolated rat hearts. In this study we investigated the effects of liguzinediol on a rat model of heart failure. Methods: To induce heart failure, male SD rats were injected with doxorubicin (DOX, 2 mg/kg, ip) once a week for 4 weeks. Then the rats were administered with liguzinediol (5, 10, and 20 mg.kg(-1).d(-1), po) for 2 weeks. Hemodynamic examination was conducted to evaluate heart function. Myocardial cell apoptosis was examined morphologically. The expression of related genes and proteins were analyzed using immunohistochemical staining and Western blot assays, respectively. Results: Oral administration of liguzinediol dose-dependently improved the heart function in DOX-treated rats. Electron microscopy revealed that liguzinediol (10 mg.kg(-1).d(-1)) markedly attenuated DOX-induced injury of cardiomyocytes, and decreased the number of apoptotic bodies in cardiomyocytes. Furthermore, liguzinediol significantly decreased Bax protein level, and increased Bcl-2 protein level in cardidmyocytes of DOX-treated rats, led to an increase in the ratio of Bcl-2/Bax. Moreover, liguzinediol significantly decreased the expression of both cleaved caspase-3 and NF-kappa B in cardiomyocytes of DOX-treated rats. Administration of digitalis (0.0225 mg.kg(-1)d(-1)) also markedly improved the heart function and the morphology of cardiomyocytes in DOX-treated rats. Conclusion: Liguzinediol improves the heart function and inhibits myocardial cell apoptosis in the rat model of heart failure, which is associated with regulating BcI-2, Bax, caspase-3, and NF-kappa B expression.