{"title":"O-linked β-N-acetylglucosamine transferase regulates macrophage polarization in diabetic periodontitis: <i>In vivo</i> and <i>in vitro</i> study.","authors":"Ye-Ke Wu, Min Liu, Hong-Ling Zhou, Xiang He, Jing Wei, Wei-Han Hua, Hui-Jing Li, Qiang-Hua Yuan, Yun-Fei Xie","doi":"10.4239/wjd.v16.i3.95092","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Periodontitis, when exacerbated by diabetes, is characterized by increased M1 macrophage polarization and decreased M2 polarization. O-linked β-N-acetylglucosamine (O-GlcNAcylation), catalyzed by O-GlcNAc transferase (OGT), promotes inflammatory responses in diabetic periodontitis (DP). Additionally, p38 mitogen-activated protein kinase regulates macrophage polarization. However, the interplay between OGT, macrophage polarization, and p38 signaling in the progression of DP remains unexplored.</p><p><strong>Aim: </strong>To investigate the effect of OGT on macrophage polarization in DP and its role in mediating O-GlcNAcylation of p38.</p><p><strong>Methods: </strong>For <i>in vivo</i> experiments, mice were divided into four groups: Control, DP model, model + short hairpin (sh) RNA-negative control, and model + sh-OGT. Diabetes was induced by streptozotocin, followed by ligation and lipopolysaccharide (LPS) administration to induce periodontitis. The impact of OGT was assessed by injecting sh-OGT lentivirus. Maxillary bone destruction was evaluated using micro-computed tomography analysis and tartrate-resistant acid phosphatase staining, while macrophage polarization was determined through quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry. For <i>in vitro</i> experiments, RAW264.7 cells were treated with LPS and high glucose (HG) (25 mmol/L D-glucose) to establish a cell model of DP. OGT was inhibited by OGT inhibitor (OSMI4) treatment and knocked down by sh-OGT transfection. M1/M2 polarization was analyzed using qPCR, immunofluorescence, and flow cytometry. Levels of O-GlcNAcylation were measured using immunoprecipitation and western blotting.</p><p><strong>Results: </strong>Our results demonstrated that M1 macrophage polarization led to maxillary bone loss in DP mice, associated with elevated O-GlcNAcylation and OGT levels. Knockdown of OGT promoted the shift from M1 to M2 macrophage polarization in both mouse periodontal tissues and LPS + HG-induced RAW264.7 cells. Furthermore, LPS + HG enhanced the O-GlcNAcylation of p38 in RAW264.7 cells. OGT interacted with p38 to promote its O-GlcNAcylation at residues A28, T241, and T347, as well as its phosphorylation at residue Y221.</p><p><strong>Conclusion: </strong>Inhibition of OGT-mediated p38 O-GlcNAcylation deactivates the p38 pathway by suppressing its self-phosphorylation, thereby promoting M1 to M2 macrophage polarization and mitigating DP. These findings suggested that modulating macrophage polarization through regulation of O-GlcNAcylation may represent a novel therapeutic strategy for treating DP.</p>","PeriodicalId":48607,"journal":{"name":"World Journal of Diabetes","volume":"16 3","pages":"95092"},"PeriodicalIF":4.2000,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11885980/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"World Journal of Diabetes","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.4239/wjd.v16.i3.95092","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: Periodontitis, when exacerbated by diabetes, is characterized by increased M1 macrophage polarization and decreased M2 polarization. O-linked β-N-acetylglucosamine (O-GlcNAcylation), catalyzed by O-GlcNAc transferase (OGT), promotes inflammatory responses in diabetic periodontitis (DP). Additionally, p38 mitogen-activated protein kinase regulates macrophage polarization. However, the interplay between OGT, macrophage polarization, and p38 signaling in the progression of DP remains unexplored.
Aim: To investigate the effect of OGT on macrophage polarization in DP and its role in mediating O-GlcNAcylation of p38.
Methods: For in vivo experiments, mice were divided into four groups: Control, DP model, model + short hairpin (sh) RNA-negative control, and model + sh-OGT. Diabetes was induced by streptozotocin, followed by ligation and lipopolysaccharide (LPS) administration to induce periodontitis. The impact of OGT was assessed by injecting sh-OGT lentivirus. Maxillary bone destruction was evaluated using micro-computed tomography analysis and tartrate-resistant acid phosphatase staining, while macrophage polarization was determined through quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry. For in vitro experiments, RAW264.7 cells were treated with LPS and high glucose (HG) (25 mmol/L D-glucose) to establish a cell model of DP. OGT was inhibited by OGT inhibitor (OSMI4) treatment and knocked down by sh-OGT transfection. M1/M2 polarization was analyzed using qPCR, immunofluorescence, and flow cytometry. Levels of O-GlcNAcylation were measured using immunoprecipitation and western blotting.
Results: Our results demonstrated that M1 macrophage polarization led to maxillary bone loss in DP mice, associated with elevated O-GlcNAcylation and OGT levels. Knockdown of OGT promoted the shift from M1 to M2 macrophage polarization in both mouse periodontal tissues and LPS + HG-induced RAW264.7 cells. Furthermore, LPS + HG enhanced the O-GlcNAcylation of p38 in RAW264.7 cells. OGT interacted with p38 to promote its O-GlcNAcylation at residues A28, T241, and T347, as well as its phosphorylation at residue Y221.
Conclusion: Inhibition of OGT-mediated p38 O-GlcNAcylation deactivates the p38 pathway by suppressing its self-phosphorylation, thereby promoting M1 to M2 macrophage polarization and mitigating DP. These findings suggested that modulating macrophage polarization through regulation of O-GlcNAcylation may represent a novel therapeutic strategy for treating DP.
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.