抑制免疫抑制因子COX-2对视网膜神经节细胞凋亡的影响及p38MAPK信号的调控作用

Effect of inhibition of immunosuppressive factor COX-2 on apoptosis of retinal ganglion cells and regulation of p38MAPK signal pathway

目的:探讨环氧合酶-2(COX-2)抑制剂NS-398对H_2O_2诱导的视网膜神经节RGC-5细胞活力和凋亡及p38MAPK信号通路的调控作用。方法:200、300、400、600、800μmol/L的H_2O_2刺激视网膜神经节RGC-5细胞建立H_2O_2损伤模型,根据半数抑制浓度选择H_2O_2的浓度; COX-2抑制剂NS-398处理H_2O_2诱导的RGC-5细胞7 h,SB203580作为p38MAPK信号通路抑制剂,通过MTT法及流式细胞术分别检测细胞的活力和凋亡率; Western blot检测细胞增殖核抗原(PCNA)、p53、p38丝裂原活化蛋白激酶(p38MAPK)、p-p38的蛋白表达。结果:不同浓度的H_2O_2均可抑制RGC-5细胞活力,且随H_2O_2浓度升高细胞活力降低,由于400μmol/L的H_2O_2可抑制一半的细胞活力,选择作为研究对象;与空白对照组比较,H_2O_2组细胞活力及PCNA蛋白表达均显著降低,细胞凋亡率及p53和p-p38的蛋白表达均显著升高,与H_2O_2组比较,H_2O_2+NS-398组细胞活力及PCNA蛋白表达均显著升高,细胞凋亡率及p53和p-p38的蛋白表达均显著降低(P<0. 05);与H_2O_2+NS-398组比较,H_2O_2+NS-398+SB203580组细胞活力及PCNA蛋白表达均显著升高,细胞凋亡率及p53和p-p38的蛋白表达均显著降低(P<0. 05)。结论:抑制免疫抑制因子COX-2表达可通过调控p38MAPK信号通路提高视网膜神经节细胞活力和抑制细胞凋亡。

Objective:To investigate the effect of COX-2 inhibitor bevacizumab on the activity and apoptosis of retinal ganglion RGC-5 cells induced by H2O2 and the regulation of p38MAPK signaling pathway.Methods:Retinal ganglion RGC-5 cells was stimulated using H2O2(200,300,400,600,800μmol/L)to establish a H2O2 damage model,H2O2 concentration was selected based on half inhibitory concentration,COX-2 inhibitor bevacizumab treated RGC-5 cell induced by H2O2 for 7 h,SB203580 as a p38MAPK signaling pathway inhibitor,cell viability and apoptosis rate were detected by MTT method and flow cytometry,respectively;the expression of PCNA,p53,p38 and p-p38 protein were detected by Western blot.Results:Different concentrations of H2O2 could inhibit the viability of RGC-5 cells,and the cell viability decreased with the increase of H2O2 concentration,because 400μmol/L H2O2 inhibited half of the cell viability,it was selected as an object of study.Compared with the control group,the cell viability and the expression of PCNA were decreased significantly in H2O2 group,the apoptosis rate and the expression of p53 and p-p38 protein was increased significantly;compared with H2O2 group,the cell viability and PCNA expression were increased significantly in the H2O2+bevacizumab group,the apoptosis rate and the expression of p53 and p-p38 protein were decreased significantly(P<0.05);compared with H2O2+bevacizumab group,the cell viability and PCNA expression were increased significantly in H2O2+bevacizumab+SB203580 group,the apoptosis rate and the expression of p53 and p-p38 protein were decreased significantly(P<0.05).Conclusion:Inhibition of immunosuppressive factor COX-2 expression can improve the activity of retinal ganglion cells and inhibit apoptosis by regulating the p38MAPK signaling pathway.