苦参碱在调节Bax和Bcl-2蛋白表达诱导Hep G2细胞凋亡中的作用

The Role of Matrine in Regulating the Expression of Bax and Bcl-2 in Hep G2 Cells Which Induce Apoptosis

目的:探讨Bax和Bcl-2蛋白在苦参碱诱导HepG2细胞凋亡中的作用。方法:采用MTT法和细胞凋亡ELISA试剂盒检测细胞活力和凋亡;用蛋白印迹试验(Western blotting)检测细胞内Bax,Bcl-2,Caspase-9和Caspase-3蛋白的表达情况。结果:苦参碱诱导HepG2细胞凋亡,呈时间和剂量依赖性。苦参碱随时间进行性降低Bcl-2蛋白的表达,相应地稳步提高Bax蛋白的表达。而且苦参碱还促进Bax从胞浆内向线粒体移位,紧接着降解Caspase-3,-9蛋白。结论:苦参碱通过调节细胞内Bax和Bcl-2蛋白的表达经线粒体信号转导途径诱导HepG2细胞的凋亡。

Objective： To investigate the effect of Matrine on Human hepatoma cells in vitro and explore the underlying mechanism. Methods： The MTT test and cell death detection ELISA were used to determine the effect of Matrine on the viability and apoptotic death of human hepatoma cells. And then immunoblot analysis was performed to analyze the expression of Bcl and Bax. Results： Matrine induced apoptotic cell death in Hep G2 cells in a time-, and dose-dependent manner. The expression levels of the anti-apoptotic Bcl-2 in matrine-treated cells were decreased in a time-dependent manner. This reduction was coupled to a stable increased expression level of the pro-apoptotic Bax. Furthermore, the Bax was shifted from the cytosol to the mitochondria in cells treated with Matrine time-dependently, followed by cleavage of Caspase-3 and Caspase-9. Conclusion： Matrine causes death of liver cancer cells via the mitochondrial apoptotic pathway. These effects are most likely dependent on the regulation of the levels of antiapoptotic and proapoptotic proteins.