Protective effects of dioscin against isoproterenol-induced cardiac hypertrophy via adjusting PKCε/ERK-mediated oxidative stress

Cardiac hypertrophy (CH) plays a central role in cardiac remodeling and is an independent risk factor for cardiac events. It is imperative to find drugs with protective effect on CH. Dioscin, one natural product, shows various pharmacological activities, and PKCepsilon (PKCε) plays an important role in the physiological hypertrophic responses. Thus, we aimed to investigate the possible protective effect of dioscin on CH through PKCε. In the present study, the isoproterenol (ISO)-induced H9C2 cells and primary cardiomyocytes models, and the ISO-induced rat model were established, and the pharmacodynamics and mechanism of dioscin were investigated. In vitro results prompted that, dioscin significantly improved ISO-induced cardiomyocyte hypertrophy, decreased the levels of cell size, protein content of single cell, reactive oxygen species, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), beta-myosin heavy chain (β-MHC). Moreover, in vivo, changes in histopathological of the animals caused by ISO are improved by dioscin. And dioscin decreased the index of CH and the levels of CK, MDA, LDH, and increased the levels of GSH, SOD and GSH-Px. Mechanism research showed that dioscin inhibited the expression levels of PKCε, and affected the expression levels of p-MEK, p-ERK, Nrf2, Keap1 and HO-1 to inhibit oxidative stress. In addition, the results of ISO-induced CH in PKCε siRNA transfected H9C2 cells and C57BL/6 mice further showed that the protective effect of dioscin on CH, which was mediated by inhibition of PKCε/ERK signal pathway. In summary, dioscin can effectively inhibit CH by regulating PKCε-mediated oxidative stress, which should be considered as one potent candidate for new drug research and development to treat CH in the future.