Mzb1通过内质网应激途径改善过氧化氢所致人心肌细胞损伤的研究

Study on Mzb1 Ameliorates H_(2)O_(2)-Induced Injury of Human Cardiomyocytes Through Endoplasmic Reticulum Stress Pathway

目的观察边缘区B和B1细胞特异性蛋白(marginal zone B and B1 cell specific protein,Mzb1)对过氧化氢(hydrogen peroxide,H_(2)O_(2))诱导的人心肌细胞损伤的影响并探求其机制。方法培养人心肌细胞系AC16,H_(2)O_(2)(200μmol/L)诱导心肌细胞损伤模型,通过Lipofectamine®3000脂质体转染Mzb1;将细胞分为(1)对照组:培养液。(2)H_(2)O_(2)组:H_(2)O_(2)(200μmol/L)诱导12 h。(3)Mzb1+H_(2)O_(2)组:转染Mzb1,36 h后加入H_(2)O_(2)(200μmol/L)继续培养12 h。采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐[3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide,MTT]法检测细胞活力;以蛋白质印迹法检测Mzb1,内质网应激相关蛋白葡萄糖调节蛋白94(glucose-regulated protein 94,GRP94)、CCAAT/增强子结合蛋白的同源蛋白(CCAAT/enhancer binding protein homologous protein,CHOP)以及凋亡相关蛋白胱天蛋白酶3(Caspase3)的表达水平。结果与对照组比较,H_(2)O_(2)组细胞活力显著下降,Cleaved-Caspase3水平显著升高,内质网应激相关蛋白GRP94、CHOP表达水平升高,Mzb1表达量显著降低;与H2O2组比较,过表达Mzb1后,AC16细胞中Mzb1的细胞活力有所恢复,内质网应激相关蛋白GRP94、CHOP蛋白表达水平下降,细胞内Cleaved-Caspase3水平显著降低。结论Mzb1通过抑制内质网应激抑制凋亡,改善H_(2)O_(2)引起的心肌细胞损伤。

Objective To detect the effect and mechanism of marginal zone B and B1 cell specific protein(Mzb1)on human cardiomyocytes induced by hydrogen peroxide(H_(2)O_(2)).Methods AC16 human cardiomyocytes were cultured,and H_(2)O_(2)(200μmol/L)was used to induce myocardial cell injury model.Mzb1 was transfected by Lipofectamine®3000 liposomes.The cells were divided into(1)control group,culture medium.(2)H_(2)O_(2) group,induced by H_(2)O_(2)(200μmol/L)for 12 h.(3)Mzb1+H_(2)O_(2) group,transfected with Mzb1,H_(2)O_(2)(200μmol/L)was added after 36 h and continued to culture for 12 h.Determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide(MTT)method is used to detect cell vitality;By western blot method to detect Mzb1,endoplasmic reticulum stress related protein glucose-regulated protein 94(GRP94),CCAAT/enhancer binding protein homologous protein(CHOP)and apoptosis-related protein Caspase3.Results Compared with the control group,cell viability was significantly decreased in H_(2)O_(2) group,Cleaved-Caspase3 levels were significantly increased,ER stress-related proteins GRP94 and CHOP expression levels were increased,and Mzb1 expression levels were significantly decreased.Compared with H_(2)O_(2) group,after overexpression of Mzb1,the cell viability of Mzb1 in AC16 cells was restored,the expression levels of ER stress-related proteins GRP94 and CHOP were decreased,and intracellular Cleaved-Caspase3 levels were significantly reduced.Conclusion Mzb1 ameliorates H_(2)O_(2)-induced cardiomyocyte apoptosis and injury by inhibiting ER stress.