α65293;硫辛酸防治2型糖尿病并发症及其线粒体修复机制研究

项目名称： α65293;硫辛酸防治2型糖尿病并发症及其线粒体修复机制研究

项目编号： No.30872121

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 蔡美琴

作者单位： 上海交通大学

项目金额： 33万元

中文摘要： 细胞实验结果显示，硫辛酸对高糖引起的ECV304的氧化损伤具有保护作用。用不同剂量的硫辛酸（0.25、0.5、1mmol/L）预处理ECV304 24h，再用30mmol/l葡萄糖作用24h，流式细胞术检测细胞线粒体ROS含量和线粒体膜电位，单细胞凝胶电泳检测细胞DNA氧化损伤情况。结果显示，经硫辛酸预处理后，ECV304的ROS含量与对照组比较，有显著性下降，且与剂量增加呈反比关系；线粒体膜电位值有显著性升高，且与剂量增加呈正比关系。 动物实验结果显示，给予蔗糖饮食的GK大鼠胰岛细胞线粒体的结构和功能都出现异常，提示蔗糖饮食会明显加速GK大鼠2型糖尿病的病变进程。免疫组化染色的结果显示，蔗糖喂养但不给予ALA干预的GK大鼠出现明显的线粒体超微结构异常。流式细胞仪检测的结果显示，氧化应激与胰岛细胞的线粒体异常有关。当给予低浓度的25mg/kgALA干预时，细胞和线粒体损伤有所改善，线粒体ROS和膜电位低于对照组，但是胰岛素仍然高于对照组。当ALA的干预剂量增加到75mg/kg和100mg/kg时，高血糖造成的细胞损伤不但没有改善，反而呈现出肝功能损伤等毒性趋势。

中文关键词： 硫辛酸；2型糖尿病；线粒体；氧化损伤

英文摘要： The study showed ALA protect ECV304 against oxidative damage induced by hyperglycemia. Pretreated ECV304 cells with different concentrations of ALA(0.25m mol/L，0.5m mol/L，1m mol/L) for 24 h. Treated cells with 30mmol/L glucose for 24h to induce oxidative damage。ROS and mitochondrial membrane potential were detected by flow cytometer. The damage of DNA was determined by single cell gel electrophoresis (SCGE). The concentrations of ROS in ALA pretreated groups were significantly decreased than 30mmol/L glucose treated group. And the mitochondrial membrane potentials in ALA pretreated groups were significantly increased than 30mmol/L glucose treated group. The animal study showed the effect of ALA on sucrose-induced pancreatic cell dysfunction in GK ratssucrose diet increased the production of mitochondrial ROS and attenuated mitochondrial membrane potentials (MmPs) in pancreatic cells. ALA supplement at 25 mg/kg.bw statistically reduced the sucrose-induced mitochondrial ROS production, regulated the mitochondrial membrane potential and restored the structure of pancreatic cells. However, higher doses of ALA, 75 mg/kg.bw and 100 mg/kg.bw, had no more therapeutic effects. 50 mg/kg.bw was likely to be the threshold value of ALA. Current results demonstrated that nutritional insults like sucrose triggered intracellular oxidative stress of pancreatic islets, resulting in cell dysfunction and insulin resistance in GK rats. Our findings also presented that therapeutic doses of ALA had significant beneficial effects to overcome the deleterious effects of sucrose insult, even restore the function and structure of pancreatic cells in GK rats, however, higher doses of ALA possibly had adverse effects.

英文关键词： αipoic Acid(ALA);Type 2 Diabetes;mitochondria; oxidative damage