title: Interleukin-1beta-induced mucin production in human airway epithelium is mediated by cyclooxygenase-2, prostaglandin E2 receptors, and cyclic AMP-protein kinase A signaling.
abstract: We reported recently that interleukin (IL)-1beta exposure resulted in a prolonged increase in MUC5AC mucin production in normal, well differentiated, human tracheobronchial epithelial (NHTBE) cell cultures, without significantly increasing MUC5AC mRNA (Am J Physiol 286:L320-L330, 2004). The goal of the present study was to elucidate the signaling pathways involved in IL-1beta-induced MUC5AC production. We found that IL-1beta increased cyclooxygenase-2 (COX-2) mRNA expression and prostaglandin (PG) E(2) production and that the COX-2 inhibitor celecoxib suppressed IL-1beta-induced MUC5AC production. Addition of exogenous PGE(2) to NHTBE cultures also increased MUC5AC production and IL-1beta-induced Muc5ac hypersecretion in tracheas from wild-type but not from COX-2-/- mice. NHTBE cells expressed all four E-prostanoid (EP) receptor subtypes and misoprostol, an EP2 and EP4 agonist, increased MUC5AC production, whereas sulprostone, an EP1 and EP3 agonist, did not. Furthermore, specific protein kinase A (PKA) inhibitors blocked IL-1beta and PGE(2)-induced MUC5AC production. However, neither inhibition of epidermal growth factor receptor (EGFR) activation with the tyrosine kinase inhibitor 4-(3-chloroanilino)-6,7-dimethoxyquinazoline HCl (AG-1478) or EGFR blocking antibody nor inhibition of extracellular signal-regulated kinase/P-38 mitogen activated protein kinases with specific inhibitors blocked IL-1beta stimulation of MUC5AC mucin production. We also observed that tumor necrosis factor (TNF)-alpha, platelet activating factor (PAF), and lipopolysaccharide (LPS) induced COX-2 and increased MUC5AC production that was blocked by celecoxib, suggesting a common signaling pathway of inflammatory mediator-induced MUC5AC production in NHTBE cells. We conclude that the induction of MUC5AC by IL-1beta, TNF-alpha, PAF, and LPS involves COX-2- generated PGE(2), activation of EP2 and/or EP4 receptor(s), and cAMP-PKA-mediated signaling.
authors.affiliation: Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA. grayt@niehs.nih.gov
authors.forename: Thomas
authors.initials: T
authors.lastname: Gray
authors.forename: Paul
authors.initials: P
authors.lastname: Nettesheim
authors.forename: Charles
authors.initials: C
authors.lastname: Loftin
authors.forename: Ja-Seok
authors.initials: JS
authors.lastname: Koo
authors.forename: James
authors.initials: J
authors.lastname: Bonner
authors.forename: Shyamal
authors.initials: S
authors.lastname: Peddada
authors.forename: Robert
authors.initials: R
authors.lastname: Langenbach
mesh_terms: D001980:Bronchi / Q000166:cytology; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D051546:Cyclooxygenase 2; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004848:Epithelium / Q000187:drug effects* / Q000378:metabolism; D066246:ErbB Receptors / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008565:Membrane Proteins; D009077:Mucins / Q000096:biosynthesis*; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D018078:Receptors, Prostaglandin E / Q000378:metabolism*; D058306:Receptors, Prostaglandin E, EP1 Subtype; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058308:Receptors, Prostaglandin E, EP3 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D015398:Signal Transduction / Q000502:physiology*; D014132:Trachea / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D007375:Interleukin-1; D007527:Isoenzymes; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D009077:Mucins; C545635:PTGER1 protein, human; C545644:PTGER2 protein, human; C545647:PTGER3 protein, human; C545650:PTGER4 protein, human; C545636:Ptger1 protein, mouse; C545645:Ptger2 protein, mouse; C545648:Ptger3 protein, mouse; C545651:Ptger4 protein, mouse; D018078:Receptors, Prostaglandin E; D058306:Receptors, Prostaglandin E, EP1 Subtype; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058308:Receptors, Prostaglandin E, EP3 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D014409:Tumor Necrosis Factor-alpha; D000242:Cyclic AMP; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D066246:ErbB Receptors; D017868:Cyclic AMP-Dependent Protein Kinases; D015232:Dinoprostone