AIM:To investigate the effect of leucine-rich-alpha-2-glycoprotein 1(LRG1)on epithelial-mesenchymal transition(EMT)in retinal pigment epithelium(RPE)cells,and to explore the role of NADPH oxidase 4(NOX4).METHODS:RPE c...AIM:To investigate the effect of leucine-rich-alpha-2-glycoprotein 1(LRG1)on epithelial-mesenchymal transition(EMT)in retinal pigment epithelium(RPE)cells,and to explore the role of NADPH oxidase 4(NOX4).METHODS:RPE cells(ARPE-19 cell line)were treated with transforming growth factor-β1(TGF-β1)to induce EMT.Changes of the m RNA and protein expression levels of LRG1 were tested in the TGF-β1 treated cells.The recombinant human LRG1 protein(r LRG1)and si RNA of LRG1 were used to establish accumulation of exogenous LRG1 model and the down-regulation of LRG1 model in ARPE-19 cells respectively,and to detect EMT-related markers including fibronectin,α-smooth muscle actin(α-SMA)and zonula occludens-1(ZO-1).The m RNA and protein expression level of NOX4 were measured according to the above treatments.VAS2870 was used as a NOX4 inhibitor in r LRG1-treated cells.EMT-related markers were detected to verify the effect of NOX4 in the process of EMT.RESULTS:TGF-β1 promoted the expression of LRG1 at both the m RNA and protein levels during the process of EMT which showed the up-regulation of fibronectin andα-SMA,as well as the down-regulation of ZO-1.Furthermore,the r LRG1 promoted EMT of ARPE-19 cells,which manifested high levels of fibronectin andα-SMA and low level of ZO-1,whereas knockdown of LRG1 prevented EMT by decreasing the expressions of fibronectin andα-SMA and increasing the expression of ZO-1 in ARPE-19 cells.Besides,the r LRG1 activated and LRG1 si RNA suppressed NOX4 expression.EMT was inhibited when VAS2870 was used in the r LRG1-treated cells.CONCLUSION:These results for the first time demonstrate that LRG1 promotes EMT of RPE cells by activating NOX4,which may provide a novel direction to explore the mechanisms of subretinal fibrosis.展开更多
AIM:To investigate the effects of nicotinamide(NAM)on bevacizumab(BEV)-induced epithelial-mesenchymal transition(EMT)of human retinal pigment epithelial cells(ARPE-19)and the underling mechanisms.METHODS:ARPE-19 cells...AIM:To investigate the effects of nicotinamide(NAM)on bevacizumab(BEV)-induced epithelial-mesenchymal transition(EMT)of human retinal pigment epithelial cells(ARPE-19)and the underling mechanisms.METHODS:ARPE-19 cells were treated with BEV for 24,48,and 72 h,and the variation degrees of EMTrelated markers(fibronectin,α-SMA,vimentin,and ZO-1)were assessed by Western blotting to select the optimal treatment time point which exhibited the most obvious changes of EMT-related markers for the subsequent experiments.Furthermore,NAM was added to the medium,the m RNA and protein levels of the EMT-related markers were then measured.The accumulation of reactive oxygen species(ROS)and H_(2)O_(2) and the total antioxidant capacity(TAC)of the cells were also measured to evaluate the level of oxidative stress.RESULTS:After being treated with BEV for 72 h,the protein expression levels of EMT-related markers in ARPE-19 cells showed significant changes.Meanwhile the levels of ROS and H_(2)O_(2) were obviously increased,and the TAC of ARPE-19 cells was decreased.Totally 72 h was chosen to be the optimal treatment time point in subsequentexperiments.Furthermore,NAM inhibited BEV-induced EMT by downregulating fibronectin,α-SMA,and vimentin and upregulating ZO-1,decreased the accumulation of ROS and H_(2)O_(2),and enhanced TAC in BEV-treated ARPE-19 cells.CONCLUSION:This study demonstrates that NAM suppressed BEV-induced EMT in ARPE-19 cells by attenuating oxidative stress.Hence,NAM may be a potential therapeutic agent for alleviating neovascular fibrosis of the ocular fundus after anti-vascular endothelial growth factor therapy.展开更多
基金Supported by the National Natural Science Foundation of China(No.81670828)the Shandong Provincial Key Research and Development Program(No.2017GSF18141)+1 种基金the Innovation Project of Shandong Academy of Medical Sciences and the National Science and Technology Major Project of China(No.2017ZX09304-010)partially supported by the Taishan Scholar Youth Professional Program(No.tspd20150215,No.tsgn20161059)。
文摘AIM:To investigate the effect of leucine-rich-alpha-2-glycoprotein 1(LRG1)on epithelial-mesenchymal transition(EMT)in retinal pigment epithelium(RPE)cells,and to explore the role of NADPH oxidase 4(NOX4).METHODS:RPE cells(ARPE-19 cell line)were treated with transforming growth factor-β1(TGF-β1)to induce EMT.Changes of the m RNA and protein expression levels of LRG1 were tested in the TGF-β1 treated cells.The recombinant human LRG1 protein(r LRG1)and si RNA of LRG1 were used to establish accumulation of exogenous LRG1 model and the down-regulation of LRG1 model in ARPE-19 cells respectively,and to detect EMT-related markers including fibronectin,α-smooth muscle actin(α-SMA)and zonula occludens-1(ZO-1).The m RNA and protein expression level of NOX4 were measured according to the above treatments.VAS2870 was used as a NOX4 inhibitor in r LRG1-treated cells.EMT-related markers were detected to verify the effect of NOX4 in the process of EMT.RESULTS:TGF-β1 promoted the expression of LRG1 at both the m RNA and protein levels during the process of EMT which showed the up-regulation of fibronectin andα-SMA,as well as the down-regulation of ZO-1.Furthermore,the r LRG1 promoted EMT of ARPE-19 cells,which manifested high levels of fibronectin andα-SMA and low level of ZO-1,whereas knockdown of LRG1 prevented EMT by decreasing the expressions of fibronectin andα-SMA and increasing the expression of ZO-1 in ARPE-19 cells.Besides,the r LRG1 activated and LRG1 si RNA suppressed NOX4 expression.EMT was inhibited when VAS2870 was used in the r LRG1-treated cells.CONCLUSION:These results for the first time demonstrate that LRG1 promotes EMT of RPE cells by activating NOX4,which may provide a novel direction to explore the mechanisms of subretinal fibrosis.
基金Supported by the National Natural Science Foundation of China(No.81670828)the Shandong Provincial Key Research and Development Program(No.2017GSF18141)+1 种基金the Innovation Project of Shandong Academy of Medical Sciences and the National Science and Technology Major Project of China(No.2017ZX09304-010)supported by the Taishan Scholar Youth Professional Program(No.tspd20150215,No.tsqn20161059)。
文摘AIM:To investigate the effects of nicotinamide(NAM)on bevacizumab(BEV)-induced epithelial-mesenchymal transition(EMT)of human retinal pigment epithelial cells(ARPE-19)and the underling mechanisms.METHODS:ARPE-19 cells were treated with BEV for 24,48,and 72 h,and the variation degrees of EMTrelated markers(fibronectin,α-SMA,vimentin,and ZO-1)were assessed by Western blotting to select the optimal treatment time point which exhibited the most obvious changes of EMT-related markers for the subsequent experiments.Furthermore,NAM was added to the medium,the m RNA and protein levels of the EMT-related markers were then measured.The accumulation of reactive oxygen species(ROS)and H_(2)O_(2) and the total antioxidant capacity(TAC)of the cells were also measured to evaluate the level of oxidative stress.RESULTS:After being treated with BEV for 72 h,the protein expression levels of EMT-related markers in ARPE-19 cells showed significant changes.Meanwhile the levels of ROS and H_(2)O_(2) were obviously increased,and the TAC of ARPE-19 cells was decreased.Totally 72 h was chosen to be the optimal treatment time point in subsequentexperiments.Furthermore,NAM inhibited BEV-induced EMT by downregulating fibronectin,α-SMA,and vimentin and upregulating ZO-1,decreased the accumulation of ROS and H_(2)O_(2),and enhanced TAC in BEV-treated ARPE-19 cells.CONCLUSION:This study demonstrates that NAM suppressed BEV-induced EMT in ARPE-19 cells by attenuating oxidative stress.Hence,NAM may be a potential therapeutic agent for alleviating neovascular fibrosis of the ocular fundus after anti-vascular endothelial growth factor therapy.
