大黄素诱导白血病K562细胞凋亡的实验研究

Experimental study of K562 leukemia cells apoptosis induced by emodin

目的:探讨大黄素对人白血病K562细胞的增殖抑制与诱导凋亡作用。方法:采用MTT法检测大黄素对K562细胞的增殖抑制作用;通过Wight-Giemsa染色(W-G染色),在普通光镜下观察细胞的形态学变化;运用AnnexinV/PI双标记法检测大黄素对K562细胞的凋亡效应;采用流式细胞技术检测细胞周期变化与凋亡情况;通过比色法检测Caspase-3、8、9的相对活性,分析大黄素诱导K562细胞凋亡的信号途径。结果:大黄素能显著抑制K562细胞的增殖,作用24、48、72h后的半数抑制率浓度分别为80、50、40μmol/L;处理组细胞在普通光镜下可见典型的凋亡形态学改变;AnnexinV/PI双标记法检测到K562细胞在大黄素的诱导下出现早期凋亡并呈剂量依赖性(P<0.01);流式细胞仪结果分析发现,处理组的K562细胞被阻滞于G0/G1期,与对照组相比,凋亡率明显升高并呈现剂量依赖性(P<0.01);大黄素可触发Caspase-3、8、9的活性增高(P<0.01)。结论:大黄素能有效地抑制K562细胞的增殖并诱导其凋亡,其机制和Caspase信号途径的活化有关。

Objective： To study the mechanism of K562 leukemia ceils proliferation and apoptosis induced by emodin. Methods： Inhibitory effect of emodin on proliferation of K562 leukemia cells was assayed by MTT method. The morphologie changes of K562 cells were observed under microscop after Wight-Giemsa staining. Apoptosis was checked by Annexin V/PI. The changes of cell cycle and apoptosis were detected by flow cytometry. The activities of Caspase-3,8,9 were checked by chromatometry to analyze the apoptosis of K562 cells. Results： The proliferation of K562 leukemia cells was significantly inhibited by emodin. The IC50 of K562 cells inhibited with emodin for 24 h, 48 h and 72 h were 80,50 and 40 μ mol/L respectively. Typical morphological changes of K562 cells were observed by microscopy. The proliferation of K562 cells was obviously inhibited in dose-dependent manner. In Annexin V/PI, emodin induced K562 cells toward apoptosis in dose-dependent manner （P〈0.01）. The result of flow cytometry indicated that the cell cycle was blocked in G0/G1 phase （P〈0.01）. After treated with emodin, the activities of Caspase-3,8,9 were significantly higher than those in the normal control （P〈0.01 ）. Conclusion： Emodin inhibits proliferation and induces apoptosis of K562 leukemia cells, and up-regulating the experession of Caspase may be one of its mechanisms.