线粒体呼吸链在高糖腹膜透析液诱导人腹膜间皮细胞层高通透性中的作用

目的 研究线粒体呼吸链在高糖腹膜透析液（PDS）诱导人腹膜间皮细胞（HPMC）通透性升高中的作用，探讨高糖PDS导致腹膜高通透状态的分子机制。 方法 体外培养HPMC，用不同浓度葡萄糖PDS加或不加抗氧化剂谷胱甘肽，培养24 h。采用跨细胞电阻（TER）技术测定HPMC通透性的变化；免疫荧光及Western印迹观察claudin-1的表达；线粒体活性氧（ROS）荧光探针检测细胞线粒体ROS的生成；线粒体呼吸链酶复合物活性检测试剂盒检测复合物Ⅰ~Ⅳ的活性变化。 结果 各组细胞的TER值均随时间的延长而下降，4.25% PDS组TER值24 h内从（34.7±1.5） Ω&#8226;cm2下降至（4.3±1.4） Ω&#8226;cm2；高糖PDS使细胞间连接蛋白claudin-1的表达显著下调，葡萄糖浓度越高作用越明显；同时高糖PDS导致线粒体呼吸链酶复合物Ⅲ活性较对照组下降89.2%（P < 0.01），进而使线粒体ROS产生增加。谷胱甘肽可逆转上述指标的变化。 结论 高浓度葡萄糖PDS通过抑制线粒体呼吸链酶复合物Ⅲ的活性，引起HPMC的氧化损伤，进而导致腹膜间皮细胞层的高通透性增高。

Role of mitochondrial respiratory chain in hyperpermeability of human peritoneal mesothelial cells induced by high glucose peritoneal dialysate

Objective To investigate the role of mitochondrial respiratory chain in the hyperpermeability of human peritoneal mesothelial cells (HPMCs) induced by high glucose peritoneal glucose PDS was also added. Transmesothelial electrical resistance (TER) measurement was examined for detection of permeability damage in HPMCs. Immunostaining and Western blotting analysis were used to detect claudin-1 expression. Mitochondrial superoxide (MitoSOX) Red staining and respiratory chain complexes activities were determined for detection of mitochondrial reactive oxygen species (ROS) production and mitochondrial complexes activities. Results TER was decreased in a time- and concentration-dependent manner after culture with high glucose PDS for was also down-regulated significantly by high glucose PDS (P＜0.01). Complex Ⅲ activity was inhibited (10.8% of control, P＜0.01) accompanied with increased mitochondrial ROS generation.These changes were partially prevented by glutathione. Conclusion Mitochondrial respiratory complex Ⅲ pathway has crucial importance in maintaining TER of HPMCs, which may reveal a valuable target for novel therapies to fight hyperpermeability of peritoneum during the prolonged PD treatment.