title: ERK1/2 mitogen-activated protein kinase selectively mediates IL-13-induced lung inflammation and remodeling in vivo.
abstract: IL-13 dysregulation plays a critical role in the pathogenesis of a variety of inflammatory and remodeling diseases. In these settings, STAT6 is believed to be the canonical signaling molecule mediating the tissue effects of IL-13. Signaling cascades involving MAPKs have been linked to inflammation and remodeling. We hypothesized that MAPKs play critical roles in effector responses induced by IL-13 in the lung. We found that Tg IL-13 expression in the lung led to potent activation of ERK1/2 but not JNK1/2 or p38. ERK1/2 activation also occurred in mice with null mutations of STAT6. Systemic administration of the MAPK/ERK kinase 1 (MEK1) inhibitor PD98059 or use of Tg mice in which a dominant-negative MEK1 construct was expressed inhibited IL-13-induced inflammation and alveolar remodeling. There were associated decreases in IL-13-induced chemokines (MIP-1alpha/CCL-3, MIP-1beta/CCL-4, MIP-2/CXCL-1, RANTES/CCL-5), MMP-2, -9, -12, and -14, and cathepsin B and increased levels of alpha1-antitrypsin. IL-13-induced tissue and molecular responses were noted that were equally and differentially dependent on ERK1/2 and STAT6 signaling. Thus, ERK1/2 is activated by IL-13 in the lung in a STAT6-independent manner where it contributes to IL-13-induced inflammation and remodeling and is required for optimal IL-13 stimulation of specific chemokines and proteases as well as the inhibition of specific antiproteases. ERK1/2 regulators may be useful in the treatment of IL-13-induced diseases and disorders.
authors.affiliation: Section of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8057, USA.
authors.forename: Patty J
authors.initials: PJ
authors.lastname: Lee
authors.forename: Xuchen
authors.initials: X
authors.lastname: Zhang
authors.forename: Peiying
authors.initials: P
authors.lastname: Shan
authors.forename: Bing
authors.initials: B
authors.lastname: Ma
authors.forename: Chun Geun
authors.initials: CG
authors.lastname: Lee
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Homer
authors.forename: Zhou
authors.initials: Z
authors.lastname: Zhu
authors.forename: Mercedes
authors.initials: M
authors.lastname: Rincon
authors.forename: Brooke T
authors.initials: BT
authors.lastname: Mossman
authors.forename: Jack A
authors.initials: JA
authors.lastname: Elias
mesh_terms: D000818:Animals; D018925:Chemokines / Q000276:immunology; D007249:Inflammation / Q000276:immunology*; D018793:Interleukin-13 / Q000494:pharmacology*; D008168:Lung / Q000276:immunology* / Q000503:physiopathology; D020782:Matrix Metalloproteinases / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D050800:STAT6 Transcription Factor / Q000172:deficiency / Q000235:genetics / Q000276:immunology
chemical_list: D018925:Chemokines; D018793:Interleukin-13; D050800:STAT6 Transcription Factor; C494100:Stat6 protein, mouse; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020782:Matrix Metalloproteinases