Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, PR China.
Ren Fail. 2010;32(9):1103-8. doi: 10.3109/0886022X.2010.504912.
High-glucose-based peritoneal dialysis solution (PDS) is considered to be one of the primary causes for the increase of ionic permeability in peritoneum as detected by transmesothelial electrical resistance (TER) measurements and claudin-1 expression. However, the mechanism is not clear. The aim of this study is to test the hypothesis that high-glucose PDS induces hyperpermeability in human peritoneal mesothelial cell (HPMC) monolayer by mitochondrial respiratory chain complex III pathway.
HPMCs were cultured in a 1 : 1 mix of Dulbecco's modified Eagle's medium (DMEM) and PDS containing 1.5% and 4.25% glucose for 24 h. A 1 : 1 mixture of 160 mg/L glutathione and 4.25% glucose PDS was also added as an antioxidant group. TER measurement and immunostaining and western blot analysis of claudin-1 expression were examined for detection of permeability damage in HPMCs. MitoSOX™ Red staining and respiratory chain complexes' activities were determined for detection of mitochondrial reactive oxygen species (ROS) production and mitochondrial complexes' activities.
TER decreased in a time- and concentration-dependent manner after culture with high-glucose PDS for 24 h. Claudin-1 was also downregulated. Complex III activity was inhibited accompanied by increasing mitochondrial ROS generation. These changes were partially prevented by glutathione.
These findings demonstrate that mitochondrial respiratory complex III pathway has crucial importance in maintaining permeability of HPMCs, which might reveal a valuable target for novel therapies to fight hyperpermeability of peritoneum during the prolonged PD treatment.
高糖基腹膜透析液（PDS）被认为是通过跨上皮电阻（TER）测量和 Claudin-1 表达检测到的腹膜离子通透性增加的主要原因之一。然而，其机制尚不清楚。本研究旨在通过检测线粒体呼吸链复合物 III 途径来验证高糖 PDS 是否会导致人腹膜间皮细胞（HPMC）单层通透性增加的假设。
将 HPMC 在含有 1.5%和 4.25%葡萄糖的 1:1 混合 DMEM 和 PDS 中培养 24 小时。还添加了 160mg/L 谷胱甘肽和 4.25%葡萄糖 PDS 的 1:1 混合物作为抗氧化剂组。通过 TER 测量、Claudin-1 表达的免疫染色和 Western blot 分析检测 HPMC 通透性损伤。通过 MitoSOX™ Red 染色和呼吸链复合物活性测定检测线粒体活性氧（ROS）产生和线粒体复合物活性。
用高糖 PDS 培养 24 小时后，TER 呈时间和浓度依赖性下降。Claudin-1 也下调。复合物 III 活性受到抑制，同时线粒体 ROS 生成增加。这些变化部分被谷胱甘肽阻止。
这些发现表明，线粒体呼吸链复合物 III 途径对维持 HPMC 的通透性具有重要意义，这可能为延长 PD 治疗期间腹膜高通透性的新型治疗方法提供有价值的靶点。
