摘要
目的:探讨牛磺酸脱氧胆酸(TDCA)诱导HepG2细胞凋亡的分子机制。方法:应用HE染色、电镜和DNA电泳对细胞凋亡定性;应用流式细胞仪对细胞凋亡定量;检测TDCA诱导HepG2细胞凋亡过程中,线粒体细胞色素C释放及凋亡特异性蛋白酶Caspase-3、8、9活性的变化。结果:TDCA 400μmol/L孵育12h可诱导显著HepG2细胞凋亡,凋亡率为50.4±2.20％;TDCA诱导HepG2细胞凋亡过程中,线粒体细胞色素C释放呈时间依赖性增加,同时伴有Caspase-9,3蛋白酶活性显著增高,Caspase-8活性仅轻度增高。结论:启动线粒体细胞色素C释放及随后激活Caspase-9途径,可能是TDCA诱导HepG2细胞凋亡的主要机制。
AIM: To investigate the molecular mechanism of HepG2 cell apoptosis induced by Taurodeoxycholic acid (TDCA). METHODS: Morphologic evaluations of apoptosis were performed by HE staining and electro-microscope. DNA fragment was detected by electrophoresis on 1.5 % agarose gel. Apoptosis rate was measured by flow cytometry using PI probe. After incubation of HepG2 cell with TDCA, the release of cytochrome C from mitochondria into cytosol was determined by Western blot analysis, and the activitives of Caspase-8,9,3 were evaluated by chrolometry. KESULTS: Incubation of HepG2 cells with 400 μmol/L TDCA for 12 h induced significant cell apoptosis. Flow cytometry analysis showed that apoptosis rate was 50.4±2.2 % following TDCA incubation. The release of cytochrome C from mito- chondria to cytosol in a time-dependent pattern was dem- onstrated during the development of apoptosis with sub- sequent activation of Caspase-9 dnd 3 obviously, while the activation of Caspase-8 was slightly involved in this apoptotic pathway. CONCLUSION: TDCA can induce cell apoptosis mainly through initiating the release of cytochrome C from mitochondria to cytosol and the subsequent activation of procaspase-9.
出处
《世界华人消化杂志》
CAS
2003年第8期1148-1151,共4页
World Chinese Journal of Digestology
