Effect of Artesunate on Proliferation, Cell Cycle and Apoptosis of SKM-1 Cells and Its Underlying Mechanisms

Abstract

To investigate the effects of artesunate (ART) on proliferation, cell cycle and apoptosis of SKM-1 cells in vitro and to explore the underlying mechanisms. After SKM-1 cells were treated with different concentrations of ART, the cell proliferation was determined by CCK-8 method. Apoptosis and distribution of cell cycle were detected by flow cytometry. Both DCFH-DA fluorescent probe and Fluo-3-Am fluorescent probe were used to detect the changes of intracellular reactive oxygen species (ROS) and calcium ion concentration. Western blot was used to measure the protein levels of BCL-2, BAX, BAD, P-BAD, survivin and XIAP. ART obviously inhibited the growth of SKM-1 cells in time and dose-dependent manners (r = -0.841; r = 0.-786). The antioxidant trolox-pretreatment significantly decreased the growth inhibition effect of ART on SKM-1 cells. Caspase inhibitor Ac-DEVD-CHO partially reduced the growth inhibition effect of ART on SKM-1 cells. After treatment with ART for 24 hours, the apoptosis of SKM-1 cells was found, the cell cycle of SKM-1 was arrested in G0/G1 phase, ART could elevate the levels of calciumion and reactive orygen. ART could significantly down-regulate the protein expression levels of P-BAD and survivin in SKM-1 cells, and showed a highly negative correlation with ART dose (r = -0.909; r = -0.849). On the contrary, ART had no significant effect on expression levels of BAD and XIAP in SKM-1 cells, and after ART treatment, although BCL-2 protein expression was not significantly different when compared with control group, but the BCL-2/BAX ratio significantly decreased and highly negatively correlated with ART dose (r = -0.866). The ART significantly suppresses the cell proliferation, induces the apoptosis and promoted cell cycle arrest at G0/G1 phase in SKM-1 cells. The mechanisms of ART anti-MDS is associated with the increase of intracellular calciumion concentration and ROS levels. In addition, the pro-apoptotic activity of ART may be involved in the regulation of BCL-2 /BAX ratio and the expressions of P-bad and survivin.