葡萄糖及游离脂肪酸对人血管内皮细胞凋亡的影响

Effects of Glucose and Free Fatty Acids on Apoptosis of Human Vascular Endothelial Cells

为了观察葡萄糖、游离脂肪酸(FFA s)对人血管内皮细胞凋亡的影响及葡萄糖与FFA s是否具有协同作用,将培养细胞随机分为五组进行干预:对照组;葡萄糖处理组;FFA s处理组;葡萄糖与FFA s联合作用组;渗透压对照组。通过电镜、DNA片段琼脂糖凝胶电泳、流式细胞仪检测细胞凋亡和细胞周期。结果:高糖、高棕榈酸组见到凋亡小体等典型凋亡改变;高糖和高FFA s使细胞阻滞在G0/G1期,凋亡峰和凋亡率明显增高(P<0.05),并呈剂量-时间依赖性;两者联用凋亡率明显高于两者单独使用(P<0.05);低浓度FFA s组细胞凋亡率与对照组无显著差异(P>0.05)。高糖和高FFA s诱导内皮细胞凋亡具有时间-效应、浓度-效应关系且具有协同作用,可能参与了糖尿病血管并发症的发病过程。

This study sought to assess effect of high level of glucose or free fatty acids （FFAs） on apoptosis of vascular endothelial cell, and to examine whether the combined presence of high concentrations of glucose and FFAs may cross-amplify their individual detrimental effect. Cultured endothelial cell sline （ECV304） were incubated with various concentrations of glucose and/or selected FFAs （palmitate and/or oleate） for 24-96 h. Microscopic changes were observed by electron microscopy. DNA fragmentation was visualized by agarose gel electrophoresis. Apoptotic percentage of endothelial cells were determined using flow cytometry. After treatment with 30 mmol/L of glucose, 0. 25 of palmitate （PA） and 0.5mmol/L of oleate （OA） respectively, typical apoptosis morphological changes including condensed chromatin, nuclear fragmentation, reduction in volume and apoptotic bodies were observed under electron microscope, and the agarose gel electrophoresis of DNA from cells treated with high levels of glucose and FFAs revealed ＂Ladder＂ pattern. Both high concentrations of glucose and FFAs elicited apoptosis in a time- and dose-dependent manner in endothelial cells, and flow cytometry showed the cells were mainly blocked at G0/G1 phase. The apoptotic percentage of endothelial cells treated with high levels of glucose plus FFAs was significantly higher than that treated with high concentration of glucose or FFAs （PA and/ or OA） alone. Both glucose and FFAs at high concentrations can induce apoptosis of endothelial cells. The combined presence of high level of glucose and FFAs may cross-amplify their individual effect.