N-乙酰基-丝氨酰-天门冬酰-赖氨酰-脯氨酸对高糖诱导足细胞损伤的保护作用及机制

Effect of N-acetyl-seryl-aspartyl-lysyl-proline on high glucose-induced podocyte injury

目的高糖可诱导足细胞损伤,促进糖尿病蛋白尿的产生及肾脏纤维化的进展。N-乙酰基-丝氨酰-天门冬酰-赖氨酰-脯氨酸(AcSDKP)是由血管紧张素转化酶水化的一种生理性四肽,可抑制肾脏纤维化。本文通过体外培养条件永生性小鼠足细胞,探讨AcSDKP对高糖诱导足细胞损伤的保护作用及可能机制。方法体外培养条件永生性小鼠足细胞,采用高糖(30 mmol/L)刺激48 h,同时予AcSDKP干预。分为正常对照组(常规低糖培养基培养)、高糖组、高糖+AcSDKP组。采用免疫荧光法检测各组细胞足细胞特异性标记物nephrin的表达改变,采用免疫印迹法检测各组足细胞纤连蛋白(fibronectin)、α-平滑肌肌动蛋白(α-SMA)的表达改变,采用免疫荧光检测各组足细胞骨架,采用流式细胞仪检测各组足细胞凋亡率。结果高糖可减少足细胞nephrin表达,AcSDKP处理后足细胞nephrin表达有所恢复。高糖组可促进足细胞间充质标记物fibronectin、α-SMA的表达升高,AcSDKP可抑制高糖刺激下足细胞fibronectin、α-SMA的表达。高糖可诱导足细胞骨架出现紊乱、重组,促进足细胞黏附性下降,诱导足细胞凋亡,AcSDKP可抑制足细胞骨架紊乱重组、改善足细胞黏附性、抑制足细胞凋亡。结论 AcSDKP可对高糖诱导的足细胞损伤发挥保护作用,其机制可能与逆转足细胞上皮-间充质转化,稳定细胞骨架、恢复足细胞黏附性及抑制足细胞凋亡有关。

Objective To investigate the effect of N-acetyl-seryl-aspartyl-lysyl-proline（AcSDKP） on podocyte injury induced by high glucose and its possible mechanisms.Methods The conditionally immortalized mouse podocytes were treated by high glucose with or without AcsDKP. The expression of nephrin and podocyte cytoskeleton was detected by immunofluorescence. Western blotting was used to detect the expression of fibronectin and α-SMA protein in podocytes. Flow cytometry was used to measure podocyte apoptosis.Results High glucose inhibited the expression of nephrin, and AcSDKP restored the expression of nephrin. High glucose promoted the expression of fibronectin and α-SMA, and AcSDKP inhibited the expression of fibronectin and α-SMA. High glucose induced the reorganization of podocyte cytoskeleton and decreased the podocyte adhesion, and AcSDKP rescued the podocyte cytoskeleton and podocyte adhesion. High glucose induced podocyte apoptosis, and AcSDKP inhibited podocyte apoptosis. Conclusions AcSDKP alleviated podocyte injury induced by high glucose via rescuing epithelial-mesenchymal transition in podocytes,making cytoskeleton stable and inhibiting podocyte apoptosis.