title: IκBα glutathionylation and reduced histone H3 phosphorylation inhibit eotaxin and RANTES.
abstract: Airway smooth muscle cells (ASMCs) secrete eotaxin and RANTES (regulated on activation, normal T-cell expressed and secreted) in response to tumour necrosis factor (TNF)-α, which is inhibited by the nuclear factor (NF)-κB inhibitor dimethylfumarate (DMF). NF-κB/IκB (inhibitor of NF-κB) glutathionylation and changes in chromatin remodelling can inhibit NF-κB activity. In this study, we determined whether NF-κB/IκB glutathionylation and reduced histone H3 phosphorylation might underlie the inhibitory effect of DMF on NF-κB activity, and eotaxin and RANTES secretion. Primary human ASMCs were treated with DMF, diamide and/or glutathione (GSH) ethylester (OEt) prior to TNF-α stimulation and were subsequently analysed by ELISA, electrophoretic mobility shift assay, immunofluorescence, co-immunoprecipitation or immunoblotting. DMF reduced intracellular GSH and induced IκBα glutathionylation (IκBα-SSG), which inhibited IκBα degradation, NF-κB p65 nuclear entry and NF-κB/DNA binding. In addition, DMF inhibited the phosphorylation of histone H3, which was possibly mediated by the inhibitory effect of DMF on mitogen- and stress-activated protein kinase (MSK)-1. However, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase MAPK and MAPK phosphatase-1, upstream of MSK-1, were not inhibited by DMF. Importantly, DMF-mediated effects on NF-κB, histone H3, eotaxin and RANTES were reversed by addition of GSH-OEt. Our data suggest that DMF inhibits NF-κB-dependent eotaxin and RANTES secretion by reduction of GSH with subsequent induction of IκBα-SSG and inhibition of histone H3 phosphorylation. Our findings offer new potential drug targets to reduce airway inflammation in asthma.
authors: Respiratory Research Group, Faculty of Pharmacy, University of Sydney, Sydney, Australia.
authors: P
authors: P
authors: Seidel
authors: M
authors: M
authors: Roth
authors: Q
authors: Q
authors: Ge
authors: I
authors: I
authors: Merfort
authors: C T
authors: CT
authors: S'ng
authors: A J
authors: AJ
authors: Ammit
mesh_terms: D000328:Adult; D000368:Aged; D002478:Cells, Cultured; D018946:Chemokine CCL5 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D019742:Chemokines, CC / Q000037:antagonists & inhibitors* / Q000378:metabolism; D003958:Diamide / Q000494:pharmacology; D000069462:Dimethyl Fumarate; D005650:Fumarates / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D010766:Phosphorylation; D012129:Respiratory Function Tests; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000378:metabolism; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D018946:Chemokine CCL5; D019742:Chemokines, CC; D005650:Fumarates; D006657:Histones; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D013439:Sulfhydryl Reagents; D014409:Tumor Necrosis Factor-alpha; D003958:Diamide; D000072000:NF-KappaB Inhibitor alpha; D038744:Ribosomal Protein S6 Kinases, 90-kDa; C116919:mitogen and stress-activated protein kinase 1; D000069462:Dimethyl Fumarate; D005978:Glutathione