七叶皂苷钠通过抑制Akt和ERK信号通路诱导HeLa细胞凋亡及对死亡受体表达的影响

 目的:探讨七叶皂苷钠诱导宫颈癌HeLa细胞凋亡的作用及其分子机制。方法:采用MTT法检测七叶皂苷钠对宫颈癌HeLa细胞的生长和增殖抑制作用；倒置显微镜观察细胞形态改变；利用annexin V-FITC/PI流式细胞术检测细胞凋亡率；采用DAPI单染法荧光显微镜下观察细胞核变化情况； 利用Western blotting检测凋亡相关蛋白［聚(ADP-核糖)聚合酶（PARP）、cleaved caspase-8、cleaved caspase-9、pro-caspase-3］和细胞存活相关信号通路（Akt、ERK）以及TRAIL受体（DR4、DR5）的变化情况。结果:七叶皂苷钠以剂量依赖的方式显著抑制宫颈癌HeLa细胞的生长和增殖；七叶皂苷钠作用于HeLa细胞后，可见典型的凋亡细胞形态学特征，细胞凋亡率显著增加；随着七叶皂苷钠浓度升高，cleaved PARP、cleaved caspase-8和cleaved caspase-9明显增多，pro-caspase-3显著减少，p-Akt和p-ERK激活减少，细胞内DR4和DR5总蛋白水平上调。结论:七叶皂苷钠通过抑制细胞存活相关信号通路，上调死亡受体水平，抑制细胞增殖，促进细胞凋亡。

Sodium aescinate induces apoptosis of HeLa cells by inhibiting Akt/ERK signaling pathways and increasing death receptor expression

AIM:To study the effects of sodium aescinate on the apoptosis of cervical cancer HeLa cells and its molecular mechanism. METHODS:MTT assay was used to detect the growth and proliferation of HeLa cells. The morphological alteration was observed under inverted microscope. Annexin V-FITC/PI double staining and DAPI nuclear staining were used to determine the apoptosis of HeLa cells induced by sodium aescinate. The apoptosis-related proteins PARP, cleaved caspase-8 and pro-caspase-3, and the proliferation-associated molecules Akt and ERK, as well as TRAIL receptors DR4 and DR5 were detected by Western blotting. RESULTS:Sodium aescinate inhibited the growth of HeLa cells in a concentration-dependent manner. Treatment with sodium aescinate induced the typical morphology of apoptotic cells and increased the apoptotic rate significantly. The cleaved PARP, cleaved caspase-8 and cleaved caspase-9 protein expression was observed. The expression of DR4 and DR5 was up-regulated. Meanwhile, pro-caspase-3 was decreased, and the levels of p-Akt and p-ERK were down-regulated by sodium aescinate in a dose-dependent manner. CONCLUSION:Sodium aescinate inhibits the proliferation and promotes the apoptosis of HeLa cells by increasing death receptor expression and repressing proliferation-associated signaling pathways.