RESUMO
Objectives To study the effect of cadmium (Cd) on the proliferation and apoptosis of mouse spermatocyte (GC-2 spd) cells and explore the underlying molecular mechanism. Methods GC-2 spd cells were cultured with 0, 5, 10, 15, 20 and 30 μM CdCl2, respectively, for 24 hours. The cell viability and IC50 of Cd were estimated based on CCK-8 data. The apoptosis of GC-2 spd cells and cellular concentration of ROS were analyzed by flow cytometry after treatment of the cells with different concentrations of CdCl2 (0, 5, 10 μM) for 24 hours. The expression levels of JNK/c-Jun signaling pathway regulatory proteins, pro-apoptotic factor Bax and anti-apoptotic factor Bcl-2, were determined by Western blot. Results Cd inhibited the proliferation of GC-2 spd cells with IC50 value of 12.99 μM, 95% CI [11.95, 14.00]. Exposure to 5 and 10 μM CaCl2 resulted in increases in apoptosis and cellular ROS generation in a dose-dependent manner, which was statistically significant compared with the control (P 0.05), the phosphorylation level of JNK and c-Jun in Cd group was highly increased as compared to the control (P < 0.05). In addition, Cd exposure significantly increased the expression of Bax protein but decreased the expression Bcl-2 protein (P < 0.05). Conclusions Cadmium induces GC-2 spd cell apoptosis by increasing concentration of ROS and regulating the JNK/c-Jun signaling pathway.
