活性氧在氯化锰致PC12细胞凋亡中的作用

Mechanism of reactive oxygen species in manganese chloride-induced apoptosis in PC12 Cells

目的探讨活性氧(ROS)在氯化锰(MnCl2)诱导PC12细胞凋亡中的作用机制。方法构建MnCl2诱导的PC12细胞模型,MTT法检测细胞存活率,流式细胞分析PC12细胞凋亡率;琼脂糖凝胶电泳检测DNA片段化程度;分光光度法检测培养基中活性氧(ROS)生成量变化;化学发光法检测细胞三磷酸腺苷(ATP)生成量和Caspase3表达量的变化;RTPCR法检测凋亡相关基因bclxl和bax的表达。结果PC12细胞存活率与MnCl2诱导浓度和诱导时间呈负相关(P<0.01);2mmolLMnCl2诱导PC12细胞36h,细胞凋亡率明显上升(P<0.01);核DNA发生明显片段化;细胞ROS生成量明显增加(P<0.001),细胞ATP生成量受到明显抑制(P<0.01);基因bclxl表达被抑制,bax表达上升(P<0.01);Caspase3在细胞凋亡中被激活(P<0.01)。结论MnCl2诱导的PC12细胞凋亡与ROS升高、线粒体功能破坏和激活Caspase3有关。

Objective To explore the mechanism of reactive oxygen species （ROS） in manganese chloride （MnC12）-induced apeptosis in PC12 cells. Methods The model that MnC12 induced apoptosis in PC12 cells was established.The apeptotic effect of MnC12 on PC12 cells was analyzed with the MTT, the flow cytometry and the DNA fragmentation. The production of ROS and ATP in MnC12-induced apoptosis of PC12 cells was examined. The influence of MnC12 on the expression of bcl-xl, bax and the activity of Caspase 3 was also analyzed. Results MnC12 triggered PC12 cells apoptosis in a dose-and time-dependent manner （P 〈 0.01）. The rate of aptosis was significantly increased （P 〈 0.01） when MnC12 of 2 mmol/L induced PC12 cells for 36 hours. The production of ROS was increased （ P 〈 0.001） and the quantity of ATP was decreased （ P 〈 0.01 ） in PC12 cells with the same inducement of MnC12. The expression of bcl-xl was inhibited and the bax was activated in this process （ P 〈 0.01）. Caspase 3 was also activated （ P 〈 0.01）. Conclusion MnC12 induces apoptosis of PC12 cells,which is related to the increase of ROS, the inhibition of the mitochondria and the activation of Caspase3.