白藜芦醇对胰岛β细胞凋亡的影响及机制探讨

摘要

目的：观察白藜芦醇对H2 O2诱导的小鼠胰岛素瘤β-TC-6细胞株（以下简称胰岛β细胞）凋亡的影响，并探讨其机制。方法将胰岛β细胞随机分为观察组、对照组、空白组，分别置于含白藜芦醇10μmol／L＋H2 O2200μmol／L、含H2 O2200μmol／L、不含H2 O2的培养基中培养48 h。采用流式细胞术检测三组细胞凋亡率及活性氧簇（ROS）， RT-PCR法检测细胞超氧化物歧化酶1（SOD1） mRNA，Western blot 法检测细胞沉默信息调节因子2相关酶类1（SIRT1）、过氧化物酶增殖物活化受体γ辅激活因子1α（PGC-1α）蛋白。结果细胞凋亡率对照组＞观察组＞空白组，P均＜0．05；细胞SOD1 mRNA的相对表达量空白组＞观察组＞对照组，P均＜0．05；ROS水平对照组＞观察组＞空白组，P均＜0．05；SIRT1蛋白表达量空白组＞观察组＞对照组，P均＜0．01；观察组、空白组PGC-1α蛋白表达量均高于对照组，P均＜0．01。结论白藜芦醇可降低H2 O2诱导的胰岛β细胞凋亡，其机制可能与其活化SIRT1／PGC-1α通路导致SOD1表达升高、ROS表达降低有关。%Objective To observe the effect of resveratrol on the apoptosis of mice insulinoma cell line β-TC-6 ( hereinafter referred to as βcells) induced by hydrogen peroxide ( H2 O2 ) , and to explore its possible mechanism. Methods The pancreatic βcells were randomly divided into the observation group, control group and blank group, which were respectively cultured in medium with 10 μmol/L resveratrol+200 μmol/L H2 O2 , 200 μmol/L H2 O2 and non-H2 O2 for 48 hours.The apoptosis rate ofβcells and reactive oxygen species ( ROS ) were calculated by flow cy-tometry, superoxide dismutase ( SOD1 ) mRNA was measured by RT-PCR, and the expression of silent information regulator factor 2-related enzyme 1 ( SIRT1 ) and peroxisome proliferator-activated receptor-γcoactivator 1α( PGC-1α) protein was determined by Western blotting.Results Comparison of the apoptosis rate:control group>observa-tion group>blank group ( all P<0.05) , comparison of SOD1 mRNA expression:blank group>observation group>control group (all P<0.05), comparison of ROS levels, control group>observation group>blank group (all P<0.05), and the comparison of SIRT1 protein: blank group>observation group>control group (all P<0.01), the expression of PGC-1αprotein in the observation group and blank group was higher than that of the control group ( all P<0.01).Conclusions Resveratrol significantly reduces the apoptosis of βcells induced by H2O2.The mechanism may be related to the activation of SIRT1/PGC-1αpathways which leads to the increased SOD1 expression and de-creased ROS expression.