水杨酸钠诱导PC12细胞凋亡的作用

Role of sodium salicylate in inducing apoptosis of PC12 cells

目的:观察水杨酸钠诱导大鼠肾上腺嗜铬细胞瘤细胞(PC12)凋亡的作用并初步探讨其机制。方法:实验于2004-07/2005-11在武汉大学完成。选择大鼠肾上腺嗜铬细胞瘤细胞(PC12)为观察对象,将PC12细胞培育于培养板,无血清同步化后随机分组。以不同浓度的水杨酸钠[低浓度(0.3125,0.625mmol/L),高浓度(1.25,2.5,5mmol/L)]处理72h,MTT法检测细胞活力;倒置显微镜和荧光显微镜下观察细胞形态;流式细胞术检测凋亡率;Westernblotting检测胞内NF-κB的含量。结果:水杨酸钠为1.25～5mmol/L时显著减少PC12细胞的存活率(P<0.01);并引起典型的凋亡形态学改变:表现为细胞体积明显缩小、变圆,部分细胞从贴壁状态变为悬浮状态,折光性减弱。流式细胞术检测细胞凋亡率,随着水杨酸钠浓度的增加,细胞凋亡率明显升高,较低浓度水杨酸钠(0.3125,0.625mmol/L)处理组凋亡率与对照组比较升高不明显(P>0.05)。高浓度水杨酸钠(1.25,2.5,5mmol/L)处理组细胞出现典型凋亡峰,凋亡率较对照组显著增高,差异有显著性(P<0.01),并且具有浓度依赖性。随着水杨酸钠作用浓度的增加,PC12细胞中NF-κBP65蛋白表达水平逐渐降低。结论:高浓度的水杨酸钠可以体外诱导PC12细胞凋亡;水杨酸钠可剂量依赖性的减少PC12细胞内的NF-κB含量。

AIM： To observe whether sodium salieylate could induce the apoptosis of adrenal gland ehromaffin tumor cell （PC12）, and primarily explore the possible mechanism. METHODS： The experiment was conducted in Wuhan University from July 2004 to November 2005. Rat adrenal gland ehromaffin tumor cell （PC12） was observed. PC12 cell was cultured in the culture plate and was randomized after synchronization without serum. Then it was treated by sodium salieylate of various concentrations [low concentration （0.312 5, 0.625 mmol/L）, high concentration （1.25, 2.5, 5mmol/L）] for 72 hours. The cell viability was determined by Methyl thiazolyl tetrazolium （MTT） assay, cell form was observed under inverted microscope and fluorescence microscope, ratio of apeptosis was detected with flow eytometry, and the content of NF-KB was assessed by Western blotting. RESULTS： Treatment of PC12 cells with sodium salieylate for 72h, in the range of 1.25-5 mmol/L, caused a great decrease in cell survival （P 〈 0.001） and induced typical morphological changes of apeptosis. It was showed that the volume of the cells deflated and became round obviously, some cells changed from adherence condition to suspension condition while the character of photonasty weakened. The ratio of apeptosis detected with flow eytometry showed that the ratio of apeptotie cells was decreased with the concentrations of sodium salieylate increasing. Compared with the control group, the ratio of apoptotie cells which had been treated with low concentration of the sodium salieylate （0.312 5, 0.625 mmol/L） did not increase obviously. But typical apeptotie peak appeared while disposal with high eoneentrationof the sodium salieylate （1.25, 2.5, 5 mmol/L）. The ratio of apeptotie cells was significantly increased as compared with the control group （P 〈 0.01）. Moreover, it was concentration-dependent. The content of NF-κB in PC12 cells was decreased with the concentrations of sodium salieylate increasing. CONCLUSION： Sodium salicylate of high concentration can induce the apoptosis of PC12 cells in vitro. Sodium salieylate can decrease the NF-κB content in a concentration-dependent manner.