糖尿病肾病MKR小鼠蛋白尿与尿中nephrin、PCX含量相关性分析

目的 通过检测糖尿病肾病（DN）MKR小鼠足细胞结构蛋白nephrin 与足细胞标记蛋白（PCX）在肾组织中的表达量及尿中的含量，分析尿微量白蛋白(UmAlb)与尿中nephrin、PCX蛋白含量的相关性。方法 取30只8周龄MKR小鼠随机分为2组（空白组和DN组），空白组以普通饲料喂养，将DN组小鼠单肾切除并加以高脂喂养2个月复制DN模型；另取15只同龄C57野生鼠为正常对照组，以普通饲料喂养。造模前1 d、喂养4周及8周后，采用电化学法检测各组小鼠空腹血糖(FBG)；喂养8周后，取各组小鼠肾脏组织，用电镜观察肾组织足细胞形态结构；Western blot检测肾组织中nephrin、PCX蛋白表达含量；ELISA 法测定尿中UmAlb含量及nephrin、PCX蛋白表达含量。结果 电镜结果显示:喂养8周后，与C57组比较，DN组小鼠肾小球足细胞结构损伤明显，DN组FBG升高( P<0.01)，且肾组织中nephrin、PCX蛋白表达下调，而尿中nephrin、PCX蛋白含量及UmAlb 含量均升高( P<0.01)。相关分析显示，尿UmAlb与尿中nephrin和PCX蛋白含量呈正相关（相关系数r=0.920,决定系数R 2=0.829， P<0.05)。结论 尿中nephrin、PCX蛋白含量与UmAlb含量呈正相关，足细胞结构蛋白丢失可能是导致糖尿病肾病蛋白尿的机制之一。

Research on the Combined Detection of Urine UmAlb and Urinary Nephrin, Podocalyxin in Podocyte of

Objective To explore the combined detection of urine UmAlb and urinary nephrin (Unephrin), podocalyxin (UPCX) in podocyte of MKR mice with diabetic nephropathy．Methods Thirty 8 weeks old MKR mice were randomly divided into two groups as follows: negative control group, DN model group, and another 15 wild C57 mice were used as normal control. Mice in DN model group were received unilateral nephrectomy and high-fat diet feed for 2 months. The morphological structure changes of the podocytes were observed by transmission electron microscopes. The levels of FBG were detected by electrochemical detection method, The nephrin and PCX protein expression were measured by western blotting. The levels of UmAlb, Unephrin and UPCX were detected by ELISA. Results The podocyte damage in the mice of DN model group increased significantly when compared with normal control. As compared with normal control, FBG in the model group increased significantly ( P<0.01), the expression level of nephrin and PCX in Renal Tissue and Unephrin, UPCX, and urine UmAlb were also increased significantly ( P<0.01). Conclusion The level of Unephrin and UPCX were positive correlated with the level of urine UmAlb, the loss of podocyte strcture protein might be one of the mechanism in leading proteinuria in diabetic nephropathy.