{"title":"SMAD specific E3 ubiquitin protein ligase 1 accelerates diabetic macular edema progression by WNT inhibitory factor 1.","authors":"Li-Fang Liang, Jia-Qi Zhao, Yi-Fei Wu, Hui-Jie Chen, Tian Huang, Xiao-He Lu","doi":"10.4239/wjd.v16.i3.101328","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Diabetic macular edema (DME) is the most common cause of vision loss in people with diabetes. Tight junction disruption of the retinal pigment epithelium (RPE) cells has been reported to induce DME development. SMAD-specific E3 ubiquitin protein ligase (SMURF) 1 was associated with the tight junctions of cells. However, the mechanism of SMURF1 in the DME process remains unclear.</p><p><strong>Aim: </strong>To investigate the role of SMURF1 in RPE cell tight junction during DME.</p><p><strong>Methods: </strong>ARPE-19 cells treated with high glucose (HG) and desferrioxamine mesylate (DFX) for establishment of the DME cell model. DME mice models were constructed by streptozotocin induction. The trans-epithelial electrical resistance and permeability of RPE cells were analyzed. The expressions of tight junction-related and autophagy-related proteins were determined. The interaction between insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) and SMURF1 mRNA was verified by RNA immunoprecipitation (RIP). SMURF1 N6-methyladenosine (m6A) level was detected by methylated RIP.</p><p><strong>Results: </strong>SMURF1 and vascular endothelial growth factor (VEGF) were upregulated in DME. SMURF1 knockdown reduced HG/DFX-induced autophagy, which protected RPE cell tight junctions and ameliorated retinal damage in DME mice. SMURF1 activated the Wnt/β-catenin-VEGF signaling pathway by promoting WNT inhibitory factor (WIF) 1 ubiquitination and degradation. IGF2BP2 upregulated SMURF1 expression in an m6A modification-dependent manner.</p><p><strong>Conclusion: </strong>M6A-modified SMURF1 promoted WIF1 ubiquitination and degradation, which activated autophagy to inhibit RPE cell tight junctions, ultimately promoting DME progression.</p>","PeriodicalId":48607,"journal":{"name":"World Journal of Diabetes","volume":"16 3","pages":"101328"},"PeriodicalIF":4.2000,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11885972/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"World Journal of Diabetes","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.4239/wjd.v16.i3.101328","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENDOCRINOLOGY & METABOLISM","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Diabetic macular edema (DME) is the most common cause of vision loss in people with diabetes. Tight junction disruption of the retinal pigment epithelium (RPE) cells has been reported to induce DME development. SMAD-specific E3 ubiquitin protein ligase (SMURF) 1 was associated with the tight junctions of cells. However, the mechanism of SMURF1 in the DME process remains unclear.
Aim: To investigate the role of SMURF1 in RPE cell tight junction during DME.
Methods: ARPE-19 cells treated with high glucose (HG) and desferrioxamine mesylate (DFX) for establishment of the DME cell model. DME mice models were constructed by streptozotocin induction. The trans-epithelial electrical resistance and permeability of RPE cells were analyzed. The expressions of tight junction-related and autophagy-related proteins were determined. The interaction between insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) and SMURF1 mRNA was verified by RNA immunoprecipitation (RIP). SMURF1 N6-methyladenosine (m6A) level was detected by methylated RIP.
Results: SMURF1 and vascular endothelial growth factor (VEGF) were upregulated in DME. SMURF1 knockdown reduced HG/DFX-induced autophagy, which protected RPE cell tight junctions and ameliorated retinal damage in DME mice. SMURF1 activated the Wnt/β-catenin-VEGF signaling pathway by promoting WNT inhibitory factor (WIF) 1 ubiquitination and degradation. IGF2BP2 upregulated SMURF1 expression in an m6A modification-dependent manner.
Conclusion: M6A-modified SMURF1 promoted WIF1 ubiquitination and degradation, which activated autophagy to inhibit RPE cell tight junctions, ultimately promoting DME progression.
期刊介绍：
The WJD is a high-quality, peer reviewed, open-access journal. The primary task of WJD is to rapidly publish high-quality original articles, reviews, editorials, and case reports in the field of diabetes. In order to promote productive academic communication, the peer review process for the WJD is transparent; to this end, all published manuscripts are accompanied by the anonymized reviewers’ comments as well as the authors’ responses. The primary aims of the WJD are to improve diagnostic, therapeutic and preventive modalities and the skills of clinicians and to guide clinical practice in diabetes. Scope: Diabetes Complications, Experimental Diabetes Mellitus, Type 1 Diabetes Mellitus, Type 2 Diabetes Mellitus, Diabetes, Gestational, Diabetic Angiopathies, Diabetic Cardiomyopathies, Diabetic Coma, Diabetic Ketoacidosis, Diabetic Nephropathies, Diabetic Neuropathies, Donohue Syndrome, Fetal Macrosomia, and Prediabetic State.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
