丝胶蛋白对链脲佐菌素诱导胰岛细胞株INS-1凋亡相关因子的影响研究

摘要

Objective To investigate the effect of sericin on apoptosis related factors Bcl-2 and Bax in Streptozotocin(STZ)-induced INS-1 cells.Methods This study was conducted from June 2015 to March 2016.INS-1 cells were divided into normal group(without any treatment),STZ group(STZ addition) and sericin group(STZ and sericin treatment).The survival rate of INS-1 cells was measured with CCK-8 assay.Apoptosis rate of INS-1 cells was detected with flow cytometry.The expression of apoptosis related factors Bcl-2 and Bax mRNA and protein were determined by RT-PCR and Western blotting,respectively.Results Compared with the STZ group,both the normal group and the sericin group had higher survival rate of INS-1 cells(P<0.05).Flow cytometry assay found that,both the normal group and sericin group had lower apoptosis rate of INS-1 cells than STZ group did(P<0.05).Compared with the normal group,the STZ group had lower expressions of Bcl-2 mRNA and protein,Bcl-2 mRNA/Bax mRNA and Bcl-2/Bax(P<0.05),but higher expressions of Bax mRNA and protein in INS-1 cells(P<0.05).Higher expressions of Bcl-2 mRNA and protein,Bcl-2 mRNA/Bax mRNA and Bcl-2/Bax and lower expressions of Bax mRNA and protein in INS-1 cells were observed in the sericin group compared with the STZ group(P<0.05).Conclusion Sericin could inhibit the apoptosis of STZ-induced INS-1 cells,and increase the Bcl-2/Bax ratio.%目的 探讨丝胶蛋白对链脲佐菌素(STZ)诱导胰岛细胞株INS-1凋亡相关因子B淋巴细胞瘤2(Bcl-2)、Bcl-2相关X蛋白(Bax)的影响.方法 2015年6月-2016年3月,将大鼠胰岛细胞株INS-1分为3组:正常组胰岛细胞株INS-1不作任何处理,STZ组以STZ作用胰岛细胞株INS-1,丝胶蛋白组以STZ和丝胶蛋白作用胰岛细胞株INS-1.CCK-8法检测各组细胞存活率;流式细胞术检测各组细胞凋亡率;实时荧光定量聚合酶链式反应(RT-PCR)法和Western blotting法检测凋亡相关因子Bcl-2和Bax mRNA表达及其蛋白的表达.结果 STZ组胰岛细胞株INS-1细胞存活率较正常组降低,丝胶蛋白组胰岛细胞株INS-1细胞存活率较STZ组升高(P<0.05).流式细胞术检测结果显示,STZ组胰岛细胞株INS-1细胞凋亡率较正常组升高,丝胶蛋白组胰岛细胞株INS-1细胞凋亡率较STZ组降低(P<0.05).STZ组胰岛细胞株INS-1 Bcl-2 mRNA及其蛋白表达水平、Bcl-2 mRNA/Bax mRNA、Bcl-2/Bax较正常组降低,Bax mRNA及其蛋白表达水平较正常组升高(P<0.05);丝胶蛋白组胰岛细胞株INS-1 Bcl-2 mRNA及其蛋白表达水平、Bcl-2 mRNA/Bax mRNA、Bcl-2/Bax较STZ组升高,Bax mRNA及其蛋白表达水平较STZ组降低(P<0.05).结论 丝胶蛋白可抑制STZ诱导的胰岛细胞株INS-1的凋亡,提高Bcl-2/Bax的比值.