中文摘要：

目的探讨雷公藤红素对体外c6胶质瘤细胞凋亡及细胞周期阻滞的影响及机制。方法雷公藤红素处理体外培养的c6胶质瘤细胞，MTT法检测细胞增殖，Hochest33342染色荧光显微镜观察以及锇铀铅染色透射电镜观察胶质瘤细胞形态变化，流式细胞术分析细胞凋亡率及细胞周期改变。蛋白印迹分析检测凋亡相关蛋白及细胞周期调控蛋白的表达变化。结果雷公藤红素对c6胶质瘤细胞的增殖抑制作用呈浓度和时间依赖性；2．56μmo／L雷公藤红素处理C6胶质瘤细胞24h后，荧光显微镜、透射电镜下均可见凋亡形态学改变。流式细胞术检查显示，凋亡细胞比例由1．32％升高到19．34％；并且，处于G0／G1期的细胞比例由76．42％降低到54．52％，G2／M期细胞比例由9．29％升高到30．50％。蛋白印迹分析显示，雷公藤红素降低了Bcl-2及XIAP蛋白表达，促进了Bax及Caspase-3的表达以及PARP的剪切；雷公藤红素在诱导细胞周期调控蛋白021、p27及cyclinB，蛋白表达增加的同时抑制了cdk2蛋白的表达。结论雷公藤红素能够通过调节凋亡相关蛋白及细胞周期相关因子的表达影响C6胶质瘤细胞的凋亡及细胞周期阻滞。

英文摘要：

Objective To investigate the effects of celastrol on the apoptosis and cell cycle arrest of C6 glioma cells and its mecbanism. Methods C6 glioma cells were cultured in vitro. MTT was used to assay cellular proliferation. Fluorescence microscope and transmission electron microscope were used to evaluate the morphological alterations of 05 glioma cells after being incubated with 2. 56 μmol/L celastrol. Flow cytometry was used to analyze the alterations of apoptosis rate and cell cycle. Results The inhibitory effects of celastrol on C6 glioma cells were dependent on celastrol concentration and incubation time. Typical morphological alterations of apoptosis were observed under photomicroscope,fluorescence microscope and transmission electron microscope respectively. Flow cytometry showed that the apoptosis rate increased from 1.32% in control group to 19. 34% in celastrol group, and cellular quantity decreased from 76. 42% to 54. 52% at G0/G1 phase but increased from 9. 29% to 30. 50% at G2/M. Western blotting analysis showed that the expression of apoptosis- related proteins Bcl- 2 and XIAP were down- regulated, but Bax,Caspase- 3 and cleaved PARP were up-regulated. Moreover,the expression of cell cycle regulator p21, p2 and cyclin BI were increased,but cdk2 was decreased. Conclusion Celastrol could induce C6 glioma cell apoptosis and cell cycle arrest via influencing the expression of apoptosis related proteins and cell cycle regulators.