Snail1/IGF-1 pathway mediates high glucose-induced EMT in renal tubular epithelial cells / 中国病理生理杂志

ABSTRACT

AIM:To observe the expression of Snail1 and insulin-like growth factor-1 (IGF-1) in NRK-52E cells induced by high glucose,and to investigate the relationship of Snail1 and IGF-1 in the mechanism of epithelial to mesenchymal transition (EMT) in diabetic kidney disease (DKD).METHODS:The NRK-52E cells were treated with Snail1 siRNA and IGF-1 siRNA after cultured with high glucose medium for 72 h,and divided into control group,high glucose group,non-targeting (NT) siRNA group,Snail1 RNAi group and IGF-1 RNAi group.The cells were harvested at 48 h and 72 h.Real-time PCR was used to detect the mRNA expression of Snail1,IGF-1,E-cadherin and fibronectin (FN),and the protein levels were determined by immunofluorescence staining.RESULTS:Compared with control group,the expression of E-cadherin at mRNA and protein levels declined after stimulation with high glucose (P ＜ 0.01),while that of FN was elevated (P ＜0.01).Meanwhile,the mRNA and protein levels of Snail1 and IGF-1 were markedly increased (P ＜0.01).The expression of E-cadherin at mRNA and protein levels was improved in Snail1 RNAi group as compared with high glucose group (P ＜ 0.01),while that of FN,IGF-l and Snail1 was significantly down-regulated (P ＜ 0.01).The same changes were observed in IGF-1 RNAi group (P ＜0.01).The protein expression of each factor in NT group had no significant change as compared with high glucose group (P ＞ 0.05).Pearson correlation analysis showed a close positive relationship between the expression of Snail1 and IGF-1 protein (r =0.852,P ＜ 0.01).CONCLUSION:Snail1 may facilitate DKD development by regulating IGF-1 in the process of EMT.