FUT8 siRNA inhibits the activation of transforming growth factor β-Smad2/3 signaling pathway in renal tubular epithelial cells / 中华肾脏病杂志

ABSTRACT

ObjectiveTo investigate the effect of FUT8-siRNA on transforming growth factor β (TGF-β)-Smad2/3 signalling pathway in renal tubular epithelial cells.MethodsHK-2 cells were divided into six groupsnormal group,negative control group,TGF-β1 group,TGF-β1 with FUT8 interference group,TGF-β1 with negative control group,FUT8 interference group.RNAi was performed to silence the expression of FUT8 gene,then immunofluorescent analysis was used to detect the expression of core fucose in the HK-2,immunoprecipitation and lectin blotting were performed to detect the core fucosylation of TGF-βR Ⅱ and ALK-5,and detect the change of Smad2/3 and p-Smad2/3 in HK-2 cells after FUT8 gene was silenced.ResultsCompared with the normal and negative control group,incubation with 5 μg/L TGF-β1 for 48 h could significantly up-regulate the core fucosylation of HK-2 cells,enhance the protein expression of TGF-βR Ⅱ and ALK-5 (P＜0.05),markedly increase the expression level of p-Smad 2/3 (P＜0.05) and cause it to nuclear translocation in HK-2 cells.While FUT8siRNA could inhibit the above up-regulation of TGF-βR Ⅱ and ALK-5(P＜0.05),suppress the increase of p-Smad 2/3(P＜0.05) and its nuclear translocation without disturbing the protein expression of TGF-βR Ⅱ and ALK-5.Conclusion FUT8-catalized core fucosylation of TGF-βR Ⅱ and ALK-5 is needed to fulfill their functions,and blocking core fucosylation of TGF-βR Ⅱ and ALK-5 leads to the inhibition of TGF-β-Smad2/3signalling pathway in HK-2 cells.