The development of subepithelial fibrosis represents an important feature of airway remodeling in asthma, and a critical role for epithelial cells herei is emerging. The pro-fibrotic cytokine, transforming growth factor beta-1 (TGF-?1) plays a cardinal role in fibrogenesis. The outcome of TGF-?1 signaling is highly dependent upon cooperation with other signaling pathways. We have recently identified a critical role for c-Jun-N-terminal- kinase 1 (JNK1) in augmenting the pro-fibrotic effects of TGF-?1, in association with the causation of a mesenchymal transition of airway epithelial cells (EMT). Specifically, we have demonstrated that: 1) JNK is predominantly activated in airway epithelium from ovalbumin-sensitized and challenged mice;2) mice lacking JNK1 (JNK1-/-) fail to induce mesenchymal genes or develop fibrosis in response to ovalbumin, TGF-?1, or bleomycin;3) TGF-?1-induced EMT requires JNK1, through JNK1-dependent phosphorylation of SMAD3 in the linker domain. These data, suggest a critical role of airway epithelium-derived JNK1-dependent signals in orchestrating airways fibrosis. The hypothesis addressed herein is that activation of JNK1 in the airway epithelium is required for the development of subepithelial fibrosis in house dust mite- induced airways disease by promoting epithelial-mesenchymal transition (EMT). Specifically, we hypothesize that JNK1 enhances TGF-?1 signaling via phosphorylation of SMAD3 in the linker domain, which enhances the competency of SMAD3 to decrease expression of let-7 microRNA (miRNA). Decreases in let-7 miRNA in turn enhances expression of the high mobility group A2 (HMGA2) gene, a proximal regulator of EMT, events that lead to subepithelial collagen deposition.
In Specific Aim 1 we will determine the importance of JNK1-dependent phosphorylation of SMAD3 in the linker domain in repressing let-7 microRNA (miRNA) in lung epithelial cells, and subsequent enhancement of the high mobility group A2 (HMGA2) gene. We will also analyze expression of let-7 miRNA and HMGA2 in bronchial epithelial cells derived from asthmatics, compared to controls, and determine the susceptibility of asthmatic and normal epithelial cells to TGF-?1-induced EMT, and elucidate the role of JNK and SMAD3 therein.
In Specific Aim 2 we will elucidate whether activation of JNK1 within the airway epithelium is critical in the orchestration of house dust mite-induced epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, and utilize mice that globally lack JNK1, or specifically within the bronchiolar epithelium, following and CRE-recombinase mediated ablation.
In Specific Aim 3 we will determine the importance of SMAD3 linker domain phosphorylation and resultant decreases of let-7g miRNA in promoting epithelial to mesenchymal transition, airways fibrosis, and altered respiratory mechanics in vivo, via the creation of TetOP-FLAG-SMAD3-EPSM mice, which are refractory to phosphorylation by JNK in the linker domain, and TetOP-FLAG-SMAD3-wild type (WT) transgenic mice, as a control. We will assess the impact of delivery of let-7g pre-miRNA on HDM-induced remodeling.

Public Health Relevance

This project will demonstrate the importance of airway epithelial cells which line the airways for the development of a scar in the lung. We have demonstrated that in mice which lack a specific signaling molecule, known as c-Jun-N-terminal kinase, are resistant to the development of a lung scar. In this project we will use sophisticated genetic tools to specifically remove this signaling protein only from epithelial cells, but not othr cell types in the lung, so that we can confirm the importance of c-jun-N-terminal kinase in epithelial cells only, for development of a scar. We will also determine the mechanism whereby c-jun-N-terminal kinase causes its scarring effects. We will also determine whether of c-jun-N-terminal kinase is active in airway epithelial cells isolated from patients with asthma, compared to control subjects. This project is important in that it will demonstrate that therapeutics to prevent scars should be directed to epithelial cells, and may provide new opportunities to stop the process of scarring in the future.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL085464-06
Application #
8602850
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Noel, Patricia
Project Start
2006-07-01
Project End
2017-01-31
Budget Start
2014-02-01
Budget End
2015-01-31
Support Year
6
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of Vermont & St Agric College
Department
Pathology
Type
Schools of Medicine
DUNS #
City
Burlington
State
VT
Country
United States
Zip Code
05405
Anathy, Vikas; Lahue, Karolyn G; Chapman, David G et al. (2018) Reducing protein oxidation reverses lung fibrosis. Nat Med 24:1128-1135
Chapman, D G; Mougey, E B; Van der Velden, J L et al. (2017) The Duffy antigen receptor for chemokines regulates asthma pathophysiology. Clin Exp Allergy 47:1214-1222
Eurlings, Irene M J; Reynaert, Niki L; van de Wetering, Cheryl et al. (2017) Involvement of c-Jun N-Terminal Kinase in TNF-?-Driven Remodeling. Am J Respir Cell Mol Biol 56:393-401
Heppner, David E; Janssen-Heininger, Yvonne M W; van der Vliet, Albert (2017) The role of sulfenic acids in cellular redox signaling: Reconciling chemical kinetics and molecular detection strategies. Arch Biochem Biophys 616:40-46
Pociask, Derek A; Robinson, Keven M; Chen, Kong et al. (2017) Epigenetic and Transcriptomic Regulation of Lung Repair during Recovery from Influenza Infection. Am J Pathol 187:851-863
Hoffman, Sidra M; Qian, Xi; Nolin, James D et al. (2016) Ablation of Glutaredoxin-1 Modulates House Dust Mite-Induced Allergic Airways Disease in Mice. Am J Respir Cell Mol Biol 55:377-86
Jones, Jane T; Qian, Xi; van der Velden, Jos L J et al. (2016) Glutathione S-transferase pi modulates NF-?B activation and pro-inflammatory responses in lung epithelial cells. Redox Biol 8:375-82
Hristova, Milena; Habibovic, Aida; Veith, Carmen et al. (2016) Airway epithelial dual oxidase 1 mediates allergen-induced IL-33 secretion and activation of type 2 immune responses. J Allergy Clin Immunol 137:1545-1556.e11
Hoffman, Sidra M; Chapman, David G; Lahue, Karolyn G et al. (2016) Protein disulfide isomerase-endoplasmic reticulum resident protein 57 regulates allergen-induced airways inflammation, fibrosis, and hyperresponsiveness. J Allergy Clin Immunol 137:822-32.e7
van der Velden, Jos L J; Ye, Ying; Nolin, James D et al. (2016) JNK inhibition reduces lung remodeling and pulmonary fibrotic systemic markers. Clin Transl Med 5:36

Showing the most recent 10 out of 24 publications