title: Rhinovirus-induced MMP-9 expression is dependent on Fra-1, which is modulated by formoterol and dexamethasone.
abstract: Matrix metalloproteinase-9 is implicated in airway inflammation and airway remodeling in asthma. We have previously confirmed that human rhinovirus-16 (HRV-16) infection increases MMP-9 expression both in vivo and in vitro. However, the role of the AP-1 sites within the MMP-9 promoter and the effect of commonly used asthma pharmacotherapies in modulating human rhinovirus (HRV)-induced MMP-9 production have not yet been elucidated. Experiments were performed in vitro in the human bronchial epithelial (HBE) cell line BEAS-2B and in primary HBE cells obtained from non-transplanted lungs. Using site-directed mutagenesis approaches, AP-1 sites were found to be necessary for HRV-induced MMP-9 promoter drive. EMSAs and supershift assays identified complexes consisting of Fos-related Ag-1 (Fra-1) in addition to other AP-1 subunits. Small interfering RNA approaches indicated that Fra-1 was induced upon HRV-16 infection in BEAS-2B cells and was necessary for MMP-9 expression in both BEAS-2B and primary HBE cells. Inhibition of MEK1/2 activity using PD98059 and U0126 reduced Fra-1 expression, DNA binding, MMP-9 promoter drive, and MMP-9 protein production. The long-acting β(2)-agonist formoterol and the glucocorticoid dexamethasone significantly reduced HRV-induced ERK phosphorylation, Fra-1, and MMP-9 expression in BEAS-2B cells. These data indicate that HRV-induced activation of the MEK/ERK MAPK pathway and Fra-1 expression are necessary for the upregulation of MMP-9 and can be modulated by two distinct but commonly used asthma pharmacotherapies. Together, these results offer insights into the mechanisms by which long-acting β(2)-agonists and glucocorticoids might reduce HRV-related asthma exacerbations.
authors.affiliation: Airway Inflammation Research Group, Snyder Institute for Chronic Diseases, Department of Medicine, University of Calgary, Calgary, Alberta T2N 4Z6, Canada.
authors.forename: Claire E
authors.initials: CE
authors.lastname: Tacon
authors.forename: Robert
authors.initials: R
authors.lastname: Newton
authors.forename: David
authors.initials: D
authors.lastname: Proud
authors.forename: Richard
authors.initials: R
authors.lastname: Leigh
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001993:Bronchodilator Agents / Q000494:pharmacology*; D002070:Butadienes / Q000494:pharmacology; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004983:Ethanolamines / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology; D000068759:Formoterol Fumarate; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects* / Q000235:genetics / Q000276:immunology; D006801:Humans; D048369:MAP Kinase Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D048370:MAP Kinase Kinase 2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D009570:Nitriles / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D010850:Picornaviridae Infections / Q000188:drug therapy / Q000201:enzymology / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D020218:Response Elements / Q000235:genetics / Q000276:immunology; D012229:Rhinovirus / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D000099169:Fos-Related Antigen 1
chemical_list: D000893:Anti-Inflammatory Agents; D001993:Bronchodilator Agents; D002070:Butadienes; D003907:Dexamethasone; D004791:Enzyme Inhibitors; D004983:Ethanolamines; D005419:Flavonoids; D000068759:Formoterol Fumarate; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; D020780:Matrix Metalloproteinase 9; D009570:Nitriles; D016760:Proto-Oncogene Proteins c-fos; D018808:Transcription Factor AP-1; D000099169:Fos-Related Antigen 1; C113580:U 0126; C482128:MAP2K2 protein, human; C482125:MAP2K1 protein, human; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one