title: The glutaredoxin/S-glutathionylation axis regulates interleukin-17A-induced proinflammatory responses in lung epithelial cells in association with S-glutathionylation of nuclear factor κB family proteins.
abstract: Interleukin-17A (IL-17A) is a newly emerging player in the pathogenesis of chronic lung diseases that amplifies inflammatory responses and promotes tissue remodeling. Stimulation of lung epithelial cells with IL-17A leads to activation of the transcription factor nuclear factor κB (NF-κB), a key player in the orchestration of lung inflammation. We have previously demonstrated the importance of the redox-dependent posttranslational modification S-glutathionylation in limiting activation of NF-κB and downstream gene induction. Under physiological conditions, the enzyme glutaredoxin 1 (Grx1) acts to deglutathionylate NF-κB proteins, which restores functional activity. In this study, we sought to determine the impact of S-glutathionylation on IL-17A-induced NF-κB activation and expression of proinflammatory mediators. C10 mouse lung alveolar epithelial cells or primary mouse tracheal epithelial cells exposed to IL-17A show rapid activation of NF-κB and the induction of proinflammatory genes. Upon IL-17A exposure, sulfenic acid formation and S-glutathionylated proteins increased. Assessment of S-glutathionylation of NF-κB pathway components revealed S-glutathionylation of RelA (RelA-SSG) and inhibitory κB kinase α (IKKα-SSG) after stimulation with IL-17A. SiRNA-mediated ablation of Grx1 increased both RelA-SSG and IKKα-SSG and acutely increased nuclear content of RelA and tended to decrease nuclear RelB. SiRNA-mediated ablation or genetic ablation of Glrx1 decreased the expression of the NF-κB-regulated genes KC and CCL20 in response to IL-17A, but conversely increased the expression of IL-6. Last, siRNA-mediated ablation of IKKα attenuated nuclear RelA and RelB content and decreased expression of KC and CCL20 in response to IL-17A. Together, these data demonstrate a critical role for the S-glutathionylation/Grx1 redox axis in regulating IKKα and RelA S-glutathionylation and the responsiveness of epithelial cells to IL-17A.
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Nolin
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Tully
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Sidra M
authors.initials: SM
authors.lastname: Hoffman
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Amy S
authors.initials: AS
authors.lastname: Guala
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Jos L
authors.initials: JL
authors.lastname: van der Velden
authors.affiliation: Department of Medicine, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Poynter
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Albert
authors.initials: A
authors.lastname: van der Vliet
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA.
authors.forename: Vikas
authors.initials: V
authors.lastname: Anathy
authors.affiliation: Department of Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA. Electronic address: yvonne.janssen@uvm.edu.
authors.forename: Yvonne M W
authors.initials: YM
authors.lastname: Janssen-Heininger
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D054418:Chemokine CCL20 / Q000096:biosynthesis; D004847:Epithelial Cells / Q000378:metabolism; D005786:Gene Expression Regulation; D054477:Glutaredoxins / Q000235:genetics*; D005978:Glutathione / Q000737:chemistry; D051550:I-kappa B Kinase / Q000235:genetics / Q000378:metabolism*; D007249:Inflammation / Q000276:immunology / Q000473:pathology; D020381:Interleukin-17 / Q000378:metabolism*; D015850:Interleukin-6 / Q000096:biosynthesis; D008168:Lung / Q000166:cytology; D008171:Lung Diseases / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D010084:Oxidation-Reduction; D011499:Protein Processing, Post-Translational; D034622:RNA Interference; D034741:RNA, Small Interfering; D020545:Respiratory Mucosa / Q000166:cytology; D013434:Sulfenic Acids / Q000378:metabolism; D014132:Trachea / Q000166:cytology; D051996:Transcription Factor RelA / Q000378:metabolism*; D051841:Transcription Factor RelB / Q000378:metabolism*
chemical_list: C493447:CCL20 protein, mouse; D054418:Chemokine CCL20; C516006:Glrx protein, mouse; D054477:Glutaredoxins; C098680:Il17a protein, mouse; D020381:Interleukin-17; D015850:Interleukin-6; D034741:RNA, Small Interfering; C498144:Rela protein, mouse; C497594:Relb protein, mouse; D013434:Sulfenic Acids; D051996:Transcription Factor RelA; D051841:Transcription Factor RelB; C496564:Chuk protein, mouse; D051550:I-kappa B Kinase; D005978:Glutathione
keywords: Free radicals; Glutaredoxin-1; Inhibitory κB kinase α; Interleukin-17A; Nuclear factor κB; Protein S-glutathionylation; Redox