Erbin在肾间质纤维化中的表达和作用

Objective To investigate the expression of Erbin in renal interstitial fibrosis (RIF) and the effect of over-expression of Erbin on transforming growth factor β1 (TGF-(β1)-induced epithelial-mesenchymal transition (EMT) in NRK52E cells. Methods In vivo, the model of renal fibrosis was induced by 5/6 subtotal nephrectomy in rat. Scr and BUN was detected and Masson staining was used to evaluate the level of renal tissue fibrosis. The location and expression of Erbin in renal tissue were detected by immunohistochemistry and Western blotting. In vitro, after NRK52E cells were treated by TGF-β1 (10 μg/L) for 72 h, immunofluorescence and Western blotting were used to obverse the expression and distribution of E-cadherin and α-SMA. The expression of Erbin mRNA and protein were detected by RT-PCR and Western blotting respectively. NRK52E cells were transiently transfected with Prk5-myc-Erbin plasmid via lipofectamine 2000, then the expressions of Erbin, E-cadherin and α-SMA were detected by Western blotting. Results (l)Compared to sham group with Scr (33.96±7.28) μmol/L and BUN (8.11±2.55) mmol/L, rats in 5/6 nephrectomy model with Scr (140.52±61.11) μmol/L and BUN (34.23±7.66) mmol/L revealed renal dysfunction. Masson staining indicated kidney interstitial fibrosis, and the expression of Erbin was significantly increased in renal tissue(2.9 folds), especially in tubular epithelia. (2)In vitro, the expressions of Erbin and α-SMA were markedly increased (2.3 folds and 2.1 folds, P<0.05, respectively) and the expression of E-cadherin was dramatically decreased in NRK52E cells stimulated by TGF-β1, which were consistent with immunofluorescence results. TGF-β1-induced E-cadherin suppression and a-SMA induction could be efficiently blocked by over-expression of Erbin (all P <0.05). Conclusions Erbin is up-regulated in renal interstitial fibrosis, and over-expression of Erbin can partly inhibit renal EMT induced by TGF-β1, which indicates Erbin playing an protective role in renal fibrosis.     

CIP4在肾间质纤维化中的表达及作用

Objective To observe the expression and localization of CIP4 (Cdc42 interacting protein-4) in the renal fibrosis and the effect of CIP4 on the expression of E-cadherin,vimentin and β-catenin tyrosine phosphorylation. Methods In vitro, the human tubular epithelial cells (HK-2 cell line) were cultured with 10 μg / L TGF-β1 for 72 h. The protein expressions of CIP4, E-cadherin, vimentin and β-catenin tyrosine phosphorylation were measured by Western blotting; the expression of CIP4 mRNA was detected by RT-PCR. The intracellular distribution of CIP4 was observe by confocal microscope. In vivo, Masson staining was used to evaluate the level of renal fibrosis; the expression and distribution of CIP4 in renal tissue were detected by immunohistochemistry. HK-2 cells were transfected with pcDNA3. 1-CIP via lipofectamine 2000. The expressions of E-cadherin, vimentin and β-catenin tyrosine phosphorylation level in the transfected cells were detected by Western blotting. Results The expressions of CIP4 mRNA and protein were up-regulated in renal tubular EMT cells. Most of CIP4 protein localized in cell membrane, and some was in cytoplasm. After stimulation by TGF-β1, the expression of CIP4 protein both in cytoplasm and nucleus was greatly increased (P ＜0.05),especially in cytoplasm. In vivo, CIP4 was expressed in renal tubular epithelia, but little expressed in glomeruli. In renal from 5/6 nephrectomized rats, CIP4 expression was significantly increased. In the CIP4 transfectants, the expression of CIP4, vimentin and β-catenin tyrosine phosphorylation level were up-regulated (P ＜0.05), but E-cadherin expression was suppressed (P ＜0.05).Conclusion The overexpression of CIP4 is likely to take part in the epithelial-to-mesenchymal transition process, thereby promoting the renal fibrosis.     

CIP4在肾间质纤维化中的表达及作用

Objective To observe the expression and localization of CIP4 (Cdc42 interacting protein-4) in the renal fibrosis and the effect of CIP4 on the expression of E-cadherin,vimentin and β-catenin tyrosine phosphorylation. Methods In vitro, the human tubular epithelial cells (HK-2 cell line) were cultured with 10 μg / L TGF-β1 for 72 h. The protein expressions of CIP4, E-cadherin, vimentin and β-catenin tyrosine phosphorylation were measured by Western blotting; the expression of CIP4 mRNA was detected by RT-PCR. The intracellular distribution of CIP4 was observe by confocal microscope. In vivo, Masson staining was used to evaluate the level of renal fibrosis; the expression and distribution of CIP4 in renal tissue were detected by immunohistochemistry. HK-2 cells were transfected with pcDNA3. 1-CIP via lipofectamine 2000. The expressions of E-cadherin, vimentin and β-catenin tyrosine phosphorylation level in the transfected cells were detected by Western blotting. Results The expressions of CIP4 mRNA and protein were up-regulated in renal tubular EMT cells. Most of CIP4 protein localized in cell membrane, and some was in cytoplasm. After stimulation by TGF-β1, the expression of CIP4 protein both in cytoplasm and nucleus was greatly increased (P ＜0.05),especially in cytoplasm. In vivo, CIP4 was expressed in renal tubular epithelia, but little expressed in glomeruli. In renal from 5/6 nephrectomized rats, CIP4 expression was significantly increased. In the CIP4 transfectants, the expression of CIP4, vimentin and β-catenin tyrosine phosphorylation level were up-regulated (P ＜0.05), but E-cadherin expression was suppressed (P ＜0.05).Conclusion The overexpression of CIP4 is likely to take part in the epithelial-to-mesenchymal transition process, thereby promoting the renal fibrosis.     

LeftyA真核表达载体的构建及其对转化生长因子-β1诱导人肾小管上皮细胞转分化的影响

目的 构建pcDNA3.1-LeftyA真核表达载体,观察其对转化生长因子-β1(TGF-β1)诱导人肾小管上皮细胞(HK-2)转分化(EMT)的影响.方法 基因克隆技术构建pcDNA3.1-LeftyA真核表达载体,将其瞬时转染HK-2细胞,TGF-β1(10μg/L)刺激后,观察细胞形态变化,检测E-钙黏蛋白(E-cadherin)、α-平滑肌肌动蛋白(α-SMA)基因及蛋白的表达.结果 TGF-β1刺激后HK-2细胞内E-cadherin mRNA和蛋白时间依赖性表达下调,α-SMA mRNA和蛋白时间依赖性表达上调,同时E-cadherin表达变化早于α-SMA;LeftyA蛋白可以显著抑制E-cadherin蛋白的下调表达(P＜0.05),其表达比同时间点单纯刺激组高17.6%;同时可逆转α-SMA蛋白的上调表达(P＜0.05),其蛋白表达比单纯刺激组低14.0%.结论 LeftyA蛋白可以抑制TGF-β1所致的EMT.

Abstract：

Objective To construct the eukaryotic expression vector for LeftyA and study the effects of LeftyA on epithelial to mesenchymal transition of human proximal tubular epithelial cells induced by transforming growth factor-β1 ( TGF-β1 ). Methods The pcDNA3. 1-LeftyA was constructed by recombinant DNA technique. After transfection with pcDNA3. 1-LeftyA HK-2 cells were stimulated by TGF-β1( 10 μg/L). The morphological changes, and the expression of E-cadherin, α-SMA and LeftyA mRNA and protein were observed and detected, respectively. Results TGF-β1 could markedly decrease the expression of E-cadherin mRNA and protein in HK-2 cells induced, and dramatically increase the expression of α-SMA mRNA and protein in a time-dependent manner. Forced expression of exogenous LeftyA led to a blockage of TGF-β1 -induced E-cadherin ( 17.6% ) suppression and α-SMA induction ( 14. 0% ). Conclusion Disruption of cell adherence is the beginning stage of EMT, and overexpression of LeftyA can suppress EMT induced by TGF-β1, which suggests a alprostadil role for LeftyA in TGF-β1-induced tubular EMT and renal fibrosis.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.     

Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway

Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.