雪胆素乙诱导刀豆蛋白A刺激的小鼠淋巴细胞凋亡及其机制的研究

Cucurbitacin IIb induces apoptosis of concanavalin A-activated mouse lymphocytes

目的:分析雪胆素乙(CuIIb)对刀豆蛋白A(Con A)刺激的小鼠淋巴细胞体外凋亡的影响,并探讨其作用机制。方法:以Annexin V染色结合流式细胞术分析小鼠淋巴细胞凋亡情况;利用JC-1染色分析淋巴细胞线粒体膜电位变化;Western blotting检测凋亡相关蛋白变化。结果:CuIIb处理后,早期和中期凋亡细胞比例明显增加,淋巴细胞线粒体膜电位降低。同时,CuIIb以剂量依赖方式激活caspase-3凋亡通路并明显降低抗凋亡蛋白survivin的表达。结论:CuIIb诱导淋巴细胞凋亡,其机制可能与其降低线粒体膜电位、激活caspase-3凋亡通路有关。

AIM： To explore the potential anti-inflammatory effect and the underlying mechanism of cucurbita cin II b （CuIIb） on concanavalin A （Con A）-activated mouse lymphocytes. METHODS： The cell apoptosis was analyzed by flow cytometry with Annexin V staining. The change of mitochondrial membrane potential was detected by JC-1 staining. The levels of caspase-3, phosphorylated H2AX and survivin were detected by Western blotting. RESULTS： Compared with Con A-activated lymphocytes, the significant increases in the proportion of the cells with reduced mitochondrial mem brane potential or with increased Annexin V staining were observed, reflecting increased apoptosis in CuIIb plus Con A treated cells. The increased levels of activated caspase-3 and phosphorylated H2AX （ a marker of double-stranded DNA breaks） were manifested in Con A-activated cells co-treated with CuIIb. Although only a slight difference of cleavage of po ly（ADP-ribose） polymerase was found in the cells with or without CuIIb treatment, the expression of survivin, an inhibitor of apoptosis protein, was markedly reduced by CuIIb in Con A-activated cells. CONCLUSION： CuIIb promotes apoptosis in mouse lymphocytes.