C_2-神经酰胺对线粒体膜间隙蛋白释放影响研究  

Effect of C_2-ceramide on release of mitochondria intermembrane space proteins

作　　者：张晓峰[1] 李百祥[1] 任锐[1] 张旸[1] 

机构地区：[1]哈尔滨医科大学公共卫生学院卫生毒理学教研室,黑龙江哈尔滨150081

出　　处：《毒理学杂志》2008年第1期1-3,共3页Journal of Toxicology

基　　金：国家自然科学基金资助项目(30471447)

摘　　要：目的探讨外源性C2-神经酰胺对线粒体膜间隙蛋白释放的影响。方法12.5、25和50μmol/L C2-神经酰胺作用人结肠癌HT-29细胞24 h,采用Mitochondrial/Cytosol Fractionation试剂盒分离细胞线粒体和细胞液,应用Western Blotting方法检测线粒体和细胞液中Cyt c、Smac和HtrA2蛋白表达水平。结果C2-神经酰胺作用细胞后,Cyt c、Smac和HtrA2总蛋白的表达水平未见明显改变,但随着C2-神经酰胺浓度增加,Cyt c、Smac和HtrA2从线粒体释放入细胞液中的水平逐渐增加,具有剂量-效应关系。Caspases抑制剂存在下,50μmol/L C2-神经酰胺仍能使Cyt c和HtrA2从线粒体释放入胞液中,但Smac却不能释放。结论C2-神经酰胺能通过Caspases依赖和非依赖的方式促进线粒体膜间隙蛋白的释放入细胞液,诱导细胞凋亡作用。Objective To investigate the effect of C2-ceramide on the release of mitochondria intermembrane space proteins. Methods Human colon carcinoma HT-29 cells were treated with 12.5,25 and 50/anol/L C2-ceramide for 24 h. Mitochondria and cytosol were extracted with mitoehondrial/cytosol fractionation kit, and western blotting was used to determine the expression of cytochrome c（Cyt c）, second mitochondria-derived activator of caspases （Smac） and high temperature requirement A2 （HtrA2） in the mitochondria and cytosol. Results There were no effect of C2-ceramide on the total expression of Cyt c, Smae and HtrA2 in HT-29 cells. But the release levels of Cyt c, Smae and HtrA2 from mitochondria into cytosol were gradually increased with the increasing concentration of C2-ceramide. Under the treatment of, caspases inhibitor 50 μmol/L C2-ceramide could induce the release of Cyt c and HtrA2 from mitochondria to cytosol, but failed to induce the release of Smac. Conclusion C2 -ceramide could promote the release of mitochondria intermembrane space proteins in easpase-dependent and caspases-independent manner, and induced apoptosis in HT-29 cells.

关 键 词：C2-神经酰胺 线粒体 线粒体膜间隙蛋白 凋亡 

分 类 号：R735.3[医药卫生—肿瘤]