SIRT2抑制对MPP^(+)诱导的帕金森病细胞模型凋亡和线粒体动态平衡的影响

The Effect of SIRT2 on Apoptosis and Mitochondrial Function in Parkinson's Disease Model Cells Induced by MPP^(+)

探究siRNA敲减沉默信息调节因子2(SIRT2)对1-甲基-4-苯基吡啶离子(MPP^(+))诱导的帕金森病细胞模型细胞损伤的影响和机制。CCK-8法检测不同浓度MPP+处理对体外培养小鼠海马神经元HT-22细胞生存率的影响。将细胞分为对照组、MPP^(+)最佳浓度处理组(1mmol/LMPP+处理组)、阴性转染组(对照组基础上转染SIRT2阴性序列)、SIRT2siRNA处理组(损伤组基础上转染SIRT2siRNA)。观察各组细胞凋亡情况,检测凋亡相关蛋白(Bcl-2、Bax、Caspase-9)、线粒体分裂及融合相关蛋白(Drp1、Fis1、OPA1、Mfn1、Mfn2)。与对照组相比,MPP+处理组细胞抑制率均升高,细胞抑制率随MPP+浓度增加而逐渐增加(P<0.05)。与SIRT2siRNA转染组相比,损伤组Bax、Caspase-9、Drp1、Fis1蛋白表达和细胞凋亡率升高,Bcl-2、Mfn1、Mfn2蛋白表达降低(P<0.05)。SIRT2在MPP+诱导帕金森病细胞模型中表达升高,抑制SIRT2可减轻MPP+诱导帕金森病细胞模型中细胞凋亡并促进线粒体融合,从而对神经元具有一定的保护作用。

To investigate the effect and mechanism of cell apoptosis of siRNA knockdown silent information regulator 2( SIRT2) in Parkinson ’s disease model cells induced by 1-methyl-4-phenylpyridinium( MPP+).Immortalized mouse hippocampal neuron HT-22 cells were cultured in vitro and treated with MPP+at different concentrations,and CCK-8 assay was used to detect cell inhibition. The cells were divided into control group,MPP+optimal concentration group( 1 mmol/L MPP+treatment,injury group),the negative transfection group( based on the control group which was transfected with SIRT2 negative sequence),and the SIRT2-siRNA treatment group( based on the injury group which was transfected with SIRT2-siRNA). The apoptosis of cells in each group was observed,apoptosis-related proteins( Bcl-2,Bax,Caspase-9) and the main proteins mediating fission and fusion of mitochondrial function( Drp1,Fis1,OPA1,Mfn1,Mfn2) were detected by Western blot.Compared with the control group,the cell inhibition rate of MPP+treatment group increased,and with the concentration increased,the inhibition rate gradually increased( P < 0. 05). Compared with the SIRT2 siRNA treatment group,the injury group increased the expression of apoptosis and mitochondrial fission factors( Bax,Caspase-9,Drp1,Fis1) and decreased the expression of anti-apoptotic and mitochondrial fusion factors( Bcl-2,Opa1,Mfn1,Mfn2). The expression of SIRT2 significantly increased in a cell model of MPP+-induced Parkinson’s disease,and the inhibition of the SIRT2 was able to decrease apoptosis,promote mitochondrial fusion,inhibit mitochondrial fission and protect neurons.