Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubula...Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.展开更多
Total saponins of Panax notoginseng （PNS） have been shown to ameliorate renal interstitial fibrosis. Ginsenoside Rg 1, a panaxatriol saponin, is one of the major active molecules from PNS. The present study was unde...Total saponins of Panax notoginseng （PNS） have been shown to ameliorate renal interstitial fibrosis. Ginsenoside Rg 1, a panaxatriol saponin, is one of the major active molecules from PNS. The present study was undertaken to investigate the effect of ginsenoside Rgl on renal fibrosis in rats with unilateral ureteral obstruction （UUO）. The rats were randomly divided into 3 groups： sham-operation （n=15）, UUO （n=15） and UUO with ginsenoside Rgl treatment （n=15, 50 mg per kg body weight, intraperitoneally （i.p.） injected）. The rats were sacrificed on Days 7 and 14 after the surgery. Histological examination demonstrated that ginsenoside Rgl significantly inhibited interstitial fibrosis including tubular injury as well as collagen deposition, u-smooth muscle actin （α-SMA） and E-cadherin are two markers of tubular epithelial-myofibroblast transition （TEMT）. Interestingly, ginsenoside Rgl notably decreased α-SMA expression and simultaneously enhanced E-cadherin expression. The messenger RNA （mRNA） of transforming growth factor-β1 （TGF-β1）, a key mediator to regulate TEMT, in the obstructed kidney increased dramatically, but was found to decrease significantly after administration of ginsenoside Rg 1. Further study showed that ginsenoside Rgl considerably decreased the levels of both active TGF-β1 and phosphorylated Smad2 （pSmad2）. Moreover, ginsenoside Rgl substantially suppressed the expression of thrombospondin-1 （TSP-1）, a cytokine which can promote the transcription of TGF-β1 mRNA and the activation of latent TGF-β1. These results suggest that ginsenoside Rgl inhibits renal interstitial fibrosis in rats with UUO. The mechanism might be partly related to the blocking of TEMT via suppressing the expression of TSP-1.展开更多
文摘Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.
基金Project (No. 30170437) supported by the National Natural Science Foundation of China
文摘Total saponins of Panax notoginseng （PNS） have been shown to ameliorate renal interstitial fibrosis. Ginsenoside Rg 1, a panaxatriol saponin, is one of the major active molecules from PNS. The present study was undertaken to investigate the effect of ginsenoside Rgl on renal fibrosis in rats with unilateral ureteral obstruction （UUO）. The rats were randomly divided into 3 groups： sham-operation （n=15）, UUO （n=15） and UUO with ginsenoside Rgl treatment （n=15, 50 mg per kg body weight, intraperitoneally （i.p.） injected）. The rats were sacrificed on Days 7 and 14 after the surgery. Histological examination demonstrated that ginsenoside Rgl significantly inhibited interstitial fibrosis including tubular injury as well as collagen deposition, u-smooth muscle actin （α-SMA） and E-cadherin are two markers of tubular epithelial-myofibroblast transition （TEMT）. Interestingly, ginsenoside Rgl notably decreased α-SMA expression and simultaneously enhanced E-cadherin expression. The messenger RNA （mRNA） of transforming growth factor-β1 （TGF-β1）, a key mediator to regulate TEMT, in the obstructed kidney increased dramatically, but was found to decrease significantly after administration of ginsenoside Rg 1. Further study showed that ginsenoside Rgl considerably decreased the levels of both active TGF-β1 and phosphorylated Smad2 （pSmad2）. Moreover, ginsenoside Rgl substantially suppressed the expression of thrombospondin-1 （TSP-1）, a cytokine which can promote the transcription of TGF-β1 mRNA and the activation of latent TGF-β1. These results suggest that ginsenoside Rgl inhibits renal interstitial fibrosis in rats with UUO. The mechanism might be partly related to the blocking of TEMT via suppressing the expression of TSP-1.
