艰难梭菌毒素A诱导结肠癌SW480细胞线粒体凋亡途径的研究

目的:探讨艰难梭菌毒素A（Tcd A）对结肠癌细胞株SW480增殖、凋亡的影响及其作用机制。方法:采用四唑蓝比色法（MTT）检测Tcd A对SW480细胞增殖的影响；流式细胞术（FCM）分析细胞凋亡情况和线粒体膜电位的变化；PI细胞荧光双染色法观察细胞凋亡的形态学变化。结果:Tcd A能显著抑制SW480细胞的增殖，且抑制率呈浓度依赖性；流式细胞仪分析处理组SW480细胞出现明显的凋亡以及线粒体膜电位的降低；细胞荧光染色观察到典型的凋亡形态学变化。结论:Tcd A可诱导SW480细胞发生凋亡，其机制可能是通过诱导线粒体膜电位的下降，破坏其外膜结构而诱发的。

Clostridium difficile toxin A-induced apoptosis on colonic carcinoma cells SW480 in mitochondrial pathway

Objective:To investigate the effects and mechanism of clostridium difficile toxin A (Tcd A)-induced apoptosis and proliferation inhibition on colonic carcinoma cell lines SW480.Methods:MTT assay was used to measure inhibition effect of SW480 cells' proliferation treated with Tcd A.Apoptosis and mitochondrial membrane potential(MMP) were detected by FCM assay.Fluorescence staining was utilized to discern typical alteration of morphology of apoptosis in SW480 cells.Results:Proliferation of SW480 cells were inhibited significantly by Tcd A in a time-and dose-dependent manner.There was typical cellular apoptosis and decline of MMP through FCM analyzing.The formulation of apoptotic morphological characteristics was observed intuitively under fluorescence microscope by cell fluorescence staining.Conclusion:Tcd A can induce apoptosis on colonic carcinoma SW480 cells and the mechanism may cause decline of MMP and damage mitochondrial structure.