VGLUT2基因表达下调对大鼠胰岛β细胞RIN-5F线粒体功能的影响

摘要

目的 探讨囊泡膜谷氨酸转运体2(VGLUT2)基因表达与大鼠胰岛β细胞RIN-5F线粒体功能之间的关系.方法 体外培养大鼠胰岛β细胞RIN-5F,分为空白组(blank组)、LipofectamineTM2000组(Lip2000组)、Control-siRNA组(采用40 nM的siRNA+Lip2000处理)和VGLUT2-siRNA组(采用40 nM的VGLUT2-siRNA+Lip2000处理).采用VGLUT2-siRNA干扰RIN-5F的VGLUT2基因表达,利用流式细胞技术和Western blot法分别检测大鼠胰岛β细胞RIN-5F线粒体膜电位与Casepase3表达在VGLUT2基因表达下调前后的变化.结果 大鼠胰岛β细胞RIN-5F受VGLUT2-siRNA干扰后,与Blank组和Control-siRNA组比较,VGLUT2-siRNA组VGLUT2 mRNA表达下调显著(P<0.05);VGLUT2-siRNA组RIN-5F线粒体膜电位下降较Control-siRNA组明显(88.3% vs.28.3%,P<0.01);VGLUT2-siRNA组的Caspase-3表达较Blank组和Control-siRNA组均明显上调(P<0.05). 结论 VGLUT2参与胰岛β细胞RIN-5F线粒体膜电位的调控以及Caspase-3的表达.%Objective The main purpose of this study is to observe the influence of VGLUT2 gene expression regulation on rat pancreatic β cell line RIN-5F mitochondria function.Methods Rat pancreatic β cell line RIN-5F were cultured in DMEM medium, cultured cells were divided into to 4 groups as blank, lip2000, control and VGLUT2 specific siRNA transfected.The VGLUT2 gene was down-regulated by its specific siRNAs on rat pancreatic β cell line RIN-5F.The mitochondria membrane potential was measured by flow cytometry.The protein level for Caspase-3 was detected by Western blot.Results After VGLUT2 specific siRNA interference, the VGLUT2 mRNA expression level was declined significantly compared with blank and control groups.The scale of decrease for mitochondria potential was lifted than control groups (88.3% vs 28.3%, P<0.01), meanwhile, the Caspase-3 protein expression was up-regulated in VGLUT2 specific siRNA groups than blank and control groups.Conclusion VGULT2 is involved in β cell apoptosis through regulation of mitochondria membrane potential and Caspase-3 expression.