神经妥乐平对H2O2致PC12细胞损伤的保护作用

目的 探索神经妥乐平对H2O2诱导的PC12细胞氧化应激损伤的影响及其潜在机制.方法 用CCK-8法检测细胞存活率,以流式细胞术检测细胞氧化损伤的发生、细胞内活性氧的生成及线粒体膜电位的变化,荧光显微镜观察细胞内活性氧的产生,qRT-PCR测定Caspase-3、Bax和Bcl-2 mRNA的表达.结果 PC12细胞存活率随H2O2浓度的增加而逐渐下降.其中,450μM H2O2处理细胞24 h后细胞存活率、凋亡率、坏死率明显降低;细胞内活性氧水平表达明显升高;线粒体膜电位JC-1红/绿荧光比值下降;Bax和Caspase-3的mRNA表达升高,而Bcl-2的mRNA表达下降,以上指标与对照组相比,差异有统计学意义(P＜0.05).而预先给予0.01UN/ml的NTP处理细胞12h可明显提高细胞存活率,降低细胞凋亡率和坏死率,减少细胞内活性氧生成并提高线粒体膜电位,抑制Bax和Caspase-3的mRNA表达,促进Bcl-2 mRNA的表达,以上指标与H2O2组相比,差异有统计学意义(P＜0.05).结论 NTP能抑制H2O2诱导的PC12细胞损伤,其神经细胞保护作用可能与其降低细胞内活性氧水平、维持线粒体膜电位的高能状态和抑制促凋亡基因表达、促进抗凋亡基因表达有关.

Neuroprotective effect of Neurotropin on H2O2-induced injury in pheochromocytoma cells

Objective To investigate the effect of Neurotropin on H2O2-induced oxidative stress injury in pheochromocytoma (PC12) cells and its potential mechanism.Methods The CCK-8 assay was applied to measure the cell viability while the flow cytometry was used to detect the occurrence of cells oxidative injury,the level of intracellular reactive oxygen species (ROS) and changes of mitochondrial membrane potential.The ROS was observed by fluorescence microscope,and the mRNA expressions of Caspase-3,Bax,and Bcl-2 were detected by immunofluorescence and quantitative real time polymerase chain reaction (qRT-PCR).Results As the increase of H2O2 concentration,the survival rate of PC 12 cells was decreased gradually.The treatment with 450 μM of H2O2 for 24 h induced the cell viability,apoptosis and necrosis significantly and increased the level of the ROS evidently;the red/green fluorescence ratios of JC-1 were decreased in the mitochondrial membrane potential;the mRNA expressions of Bax and Caspase-3 were significantly increased,while the mRNA expression of Bcl-2 was decreased (P＜0.05,compared with the control group).In contrary,with pretreatment of Neurotropin (0.01 UN/ml) for 12 h,it obviously enhanced the cell viability and mRNA expressions of Bcl-2,decreased the rates of apoptosis and necrosis,lessened the accumulation of the ROS,increased the mitochondrial membrane potential,and inhibited the expressions of Bax and Caspase-3 (P＜0.05,compared with the H2O2 group).Conclusion Neurotropin can inhibit the H2O2-induced injury in PC12 cells.Its neuroprotective role may relate to decreasing the level of the ROS,maintaining the high energy of the mitochondrial membrane potential,inhibiting the expression of proapoptotic gene expression and promoting anti-apoptotic gene expression.