目的研究铝致人神经母细胞瘤细胞(SH-SY5Y)死亡过程中MAPK信号通路的作用,探索铝致神经细胞死亡的机制。方法用4mmol/L的AlCl3·6H2O染毒SH-SY5Y细胞模拟铝致神经细胞死亡模型,用凋亡的特异性阻断剂zVAD-fmk(20μmol/L)抑制凋亡发生,用程序性坏死的特异性阻断剂necrostatin-1(Nec-1,60μmol/L)抑制程序性坏死发生,用CCK-8检测不同组间细胞活力的变化,用流式细胞术检测凋亡率及坏死率的差异,用蛋白印迹法检测MAPK信号通路蛋白磷酸化水平的改变。结果与空白对照组、溶剂对照组、zVAD—fmk对照组和Nec-1对照组相比,染铝组、凋亡抑制组和程序性坏死抑制组的细胞活力下降(P〈0.05);与染铝组相比,程序性坏死抑制组和凋亡抑制组的细胞活力上升(P〈0.05)。与空白对照组、溶剂对照组、zVAD.fmk对照组和Nec-1对照组相比,染铝组、凋亡抑制组和程序性坏死抑制组的凋亡率和坏死率上升(P〈0.05);与染铝组相比,凋亡抑制组和程序性坏死抑制组的凋亡率和坏死率下降(P〈0.05)。与空白对照组、溶剂对照组、zVAD—fmk对照组和Nec-1对照组相比,染铝组、凋亡抑制组和程序性坏死抑制组p38磷酸化水平升高,ERK磷酸化水平下降(P〈0.05);与染铝组相比,程序性坏死抑制组的p38磷酸化水平下降,ERK磷酸化水平上升(P〈0.05)。结论MAPK信号通路中的p38和ERK信号通路参与了铝致SH—SY5Y细胞程序性坏死,ERK信号通路参与了铝致SH—SY5Y细胞凋亡。而JNK信号通路耒参与铝致SH—SYSY细胞死亡。
Objective To explore the role of MAPK signaling pathway in apoptosis and necroptosis induced by aluminum in SH-SY5Y cells. Methods To imitate neural cell death induced by aluminium, AlCl3 ·6H2O (4 mmol/L) was used to treat SH-SYSY cells. Necrostatin-1 (Nec-1,60 μmol/L) ) , the specific inhibitor for necroptosis, and zVAD-fmk (20 μmol/L) , the specific inhibitor for apoptosis, were added into cultures for inhibiting the occurrence of necroptosis and apoptosis. CCK-8 was performed to measure cell viability, flow cytometry was used to test the difference of apoptosis rate and necrosis rate between groups,and western-blot was used to detect the change of MAPK protein. Results Compared with blank control group, solvent control group, Nec-1 control group and zVAD-fmk control group, cell viabiligy of Al^3+ exposed group, Al^3+ plus Nec-1 group and Al^3+ plus zVAD-fmk group decreaced ( P 〈 0.05 ). Compared with Al^3+ exposed group, cell viability of Al^3+ plus Nec-1 group and Al^3+ plus zVAD-fmk group increased (P 〈 0.05 ). Necrotic rate and apoptotic rate in Al^3+ exposed group, Al^3+ plus Nec-1 group and Al^3+ plus zVAD-fmk group obviously increased compared with blank control group, solvent control group, Nec-1 control group and zVAD-fmk control group ( P 〈 0.05 ). Compared with Al^3+ exposed group, necrotic and apaptotic rate of Al^3+ plus zVAD-fmk group and Al^3+ plus Nec-1 group were statistically significant decreased (P 〈0.05). Compared with blank control group, solvent control group, Nec-1 control group and zVAD-fmk control group, expression of p-p38 in Al^3+ exposed group, Al^3+ plus Nec-1 group and Al^3+ plus zVAD-fmk group increased obviously(P 〈 0.05) , and expression of p-ERK decreased significantly (P 〈 0.05 ). Compared with Al^3+ exposed group, expression of p-p38 decreased(P 〈 0.05 ) , but p-ERK increased in Al^3+ plus Nec-1 group (P 〈0.05). Conclusion The ERK and p38 MAPK signaling pathways are involved i