[Effect of exendin-4 on monocyte chemoattractant protein-1 expression in cultured rat glomerular mesangial cells induced by tumor necrosis factor-α in vitro].

Objective To investigate the effect of exendin-4 on the expression of monocyte chemoattractant protein-1(MCP-1) and fibronectin(FN) in rat glomerular mesangial cells in vitro.Methods Rat glomerular mesangial cells were divided into 5 groups,namely control group,tumor necrosis factor-α(TNF-α) group(10 ng/ml),TNF-α(10 ng/ml)+E1(1 nmol/L exendin-4) group,TNF-α(10 ng/ml) + E5(5 nmol/L exendin-4) group,and TNF-α(10 ng/ml) + E10(10 nmol/L exendin-4) group.After cultured 24 h or 48 h,RNA were extracted to determine the expression of MCP-1 with real-time PCR,the supernatant were collected to determine the expression of MCP-1 and FN with ELISA.Results Compared with control group,the cells treated with TNF-α for 24 h showed significantly increase the expression of MCP-1 and FN(P0.01),exendin-4 significantly reduced the expression of MCP-1 and FN in TNF-α+E5 group and TNF-α+E10 group(P0.05).After 48h incubation,the expression of MCP-1 and FN increased significantly in TNF-α group(P0.01),which was lowered by exendin-4 in TNF-α+E1,TNF-α+E5 and TNF-α+E10 groups(P0.05).Conclusion Exendin-4 has an intrinsic capability to concentration-and time-dependently inhibit TNF-α-induced expression of MCP-1 and FN in rat mesangial cells,suggesting the beneficial effect of exendin-4 in preventing and treating diabetic nephropathy.