全氟辛烷磺酸诱导HepG_2细胞凋亡的线粒体损伤机制研究

Potential mechanism of mitochondrial damage in PFOS-induced HepG_2 cell apoptosis

目的探讨全氟辛烷磺酸(PFOS)诱导人肝肿瘤Hep G_2细胞凋亡的机制。方法采用CCK-8试剂盒检测PFOS对Hep G_2细胞增殖的抑制作用;采用不同剂量PFOS染毒48 h后流式细胞术分析细胞凋亡率;JC-1试剂盒法检测线粒体膜电位;Hoechst 33258染色法观察凋亡细胞核的形态学改变;实时荧光定量PCR技术(Real-time-PCR)检测Cytochrome C、Caspase-3、AIF和Bax等凋亡相关蛋白mRNA表达水平。结果 PFOS对Hep G_2细胞增殖有明显的抑制作用;流式细胞术分析结果显示随着PFOS浓度的增加Hep G_2细胞凋亡率逐渐增加;PFOS染毒使线粒体膜电位降低并使细胞凋亡相关蛋白Cytochrome C、Caspase-3、AIF以及Bax的mRNA表达量增加。结论 PFOS可抑制Hep G_2细胞增殖并诱导其凋亡,其机制可能与影响Cytochrome C、Caspase-3、AIF和Bax等凋亡相关因子的mRNA表达水平有关。

Objective To explore effects of perfluorooctane sulphonate（ PFOS） on proliferation and apoptosis of Hep G_2 cells and the potential mechanism of mitochondrial damage. Methods A model based on human Hep G_2 cells exposed to various concentrations of PFOS for 48 hours was utilized to examine the effects of PFOS on cell proliferation and apoptosis. Cell proliferation was measured with CCK-8 cell counting kit. Mitochondrial membrane potential（ MMP） was measured by using JC-1 assay kit. The morphological changes of the nucleus were observed with fluorescent inverted microscope after staining the cells with Hoechst 33258. Cell cycle distribution and apoptotic rate were evaluated with flow cytometry（ FCM）.Quantitative real-time RT-PCR was used to detect the mRNA expressions of apoptosis related factors including Cytochrome C,Caspase-3,AIF,and Bax. Results PFOS could inhibit the proliferation of Hep G_2 cells evidently. According to FCM analysis,the apoptotic rate of Hep G_2 cells increased with increasing the doses of PFOS. The dissipation of MMP was observed after exposure to PFOS. The mRNA expressions of Cytochrome C,Caspase-3,AIF,and Bax were up-regulated. Conclusion PFOS could inhibit the proliferation and induce apoptosis of Hep G_2 cells. The mechanism might be associated with changing of the mRNA expressions including Cytochrome C,Caspase 3,AIF,and Bax.