中文摘要：

目的通过观察高糖是否引起小鼠足细胞发生上皮-间叶细胞转分化现象，探讨糖尿病肾小球损伤的可能机制。方法以小鼠永生化足细胞株为研究对象，予不同浓度葡萄糖（12．5、25、50mmol／L）处理该细胞36h，并设低糖（5．6mmol／L）和甘露醇（50mmol／L）处理组为对照组。采用蛋白免疫印迹和间接免疫荧光染色方法检测α平滑肌肌动蛋白（α-SMA）、迁连蛋白（FN）、CD2相关蛋白（CD2AP）和Wihns’肿瘤1基因（WT-1）蛋白的表达。结果低糖（5．6mmol／L）和甘露醇（50mmol／L）处理条件下小鼠足细胞表达WT-1、CD2AP，基本不表达α-SMA和FN；而予不同浓度葡萄糖处理36h后，足细胞中α-SMA和FN表达水平呈剂量依赖性上调（P〈0．05）。间接免疫荧光染色结果也显示，与低糖组相比，高糖组中α-SMA阳性的足细胞比例显著增加（P〈0．05）。同时，蛋白免疫印迹结果还表明高糖可呈剂量依赖性方式下调WT-1和CD2AP的表达（P〈0．05）。结论在高糖条件下，足细胞发生向间叶细胞表刑的转分化可能是引起足细胞功能失调，进而引起糖尿病肾小球损伤发生的作用机制之一。

英文摘要：

Objective To investigate the possible mechanism of glomerular injury in diabetes mellitus by determining whether epithelial-mesenchymal transition （EMT） is caused by high glucose in mice podocytes. Methods Using mice glomerular podocyte cell line as an in vitro system, podocytes were incubated with glueose（12.5 mmol/L, 25 mmol/L, 50 mmol/L） and mannitol （50 mmol/L） for 36 hours. Then the cells were collected and expression of alpha-smooth muscle actin（α-SMA）, fibroneetin （FN）, CD2 associated protein （CD2AP） and Wilms＇ tumor 1 gene （WT-1） was detected by Western blot and indirect immunofluorescence staining. Results Under low glucose （5.6 mmol/L） and mannitol （50 mmol/L） condition, there were high expression of CD2AP and WT-1, and low expression of α-SMA and FN in mice podoeytes. After 36 hours treatment with high glucose （12.5 mmol/L）, the expression of α-SMA and FN in podocytes was significantly increased, and the expression of α-SMA and FN was further up-regulated with the increase of glucose dosage （25, 50 mmol/L）. The indirect immunofluorescence staining revealed the similar result, and the percentage of positive α-SMA cells was also increased compared with low glucose and mannital group （P〈0.05）. Meanwhile, Western blot showed that high glucose couhl downregulate the expressions of CD2AP and WT-1 in a dose-dependent manner. Conclusion EMT may be a potential pathway leading to podocyte dysfunction and glomerular injury under high glucose conditions.