title: Involvement of c-Jun N-Terminal Kinase in TNF-α-Driven Remodeling.
abstract: Lung tissue remodeling in chronic obstructive pulmonary disease (COPD) is characterized by airway wall thickening and/or emphysema. Although the bronchial and alveolar compartments are functionally independent entities, we recently showed comparable alterations in matrix composition comprised of decreased elastin content and increased collagen and hyaluronan contents of alveolar and small airway walls. Out of several animal models tested, surfactant protein C (SPC)-TNF-α mice showed remodeling in alveolar and airway walls similar to what we observed in patients with COPD. Epithelial cells are able to undergo a phenotypic shift, gaining mesenchymal properties, a process in which c-Jun N-terminal kinase (JNK) signaling is involved. Therefore, we hypothesized that TNF-α induces JNK-dependent epithelial plasticity, which contributes to lung matrix remodeling. To this end, the ability of TNF-α to induce a phenotypic shift was assessed in A549, BEAS2B, and primary bronchial epithelial cells, and phenotypic markers were studied in SPC-TNF-α mice. Phenotypic markers of mesenchymal cells were elevated both in vitro and in vivo, as shown by the expression of vimentin, plasminogen activator inhibitor-1, collagen, and matrix metalloproteinases. Concurrently, the expression of the epithelial markers, E-cadherin and keratin 7 and 18, was attenuated. A pharmacological inhibitor of JNK attenuated this phenotypic shift in vitro, demonstrating involvement of JNK signaling in this process. Interestingly, activation of JNK signaling was also clearly present in lungs of SPC-TNF-α mice and patients with COPD. Together, these data show a role for TNF-α in the induction of a phenotypic shift in vitro, resulting in increased collagen production and the expression of elastin-degrading matrix metalloproteinases, and provide evidence for involvement of the TNF-α-JNK axis in extracellular matrix remodeling.
authors.affiliation: 1 Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Irene M J
authors.initials: IM
authors.lastname: Eurlings
authors.affiliation: 1 Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Niki L
authors.initials: NL
authors.lastname: Reynaert
authors.affiliation: 1 Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Cheryl
authors.initials: C
authors.lastname: van de Wetering
authors.affiliation: 2 Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Scott W
authors.initials: SW
authors.lastname: Aesif
authors.affiliation: 3 Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland; and.
authors.forename: Evi M
authors.initials: EM
authors.lastname: Mercken
authors.affiliation: 3 Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland; and.
authors.forename: Rafael
authors.initials: R
authors.lastname: de Cabo
authors.affiliation: 4 Department of Pathology, University of Vermont College of Medicine, Burlington, Vermont.
authors.forename: Jos L
authors.initials: JL
authors.lastname: van der Velden
authors.affiliation: 4 Department of Pathology, University of Vermont College of Medicine, Burlington, Vermont.
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Janssen-Heininger
authors.affiliation: 1 Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Emiel F M
authors.initials: EF
authors.lastname: Wouters
authors.affiliation: 1 Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Mieke A
authors.initials: MA
authors.lastname: Dentener
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015687:Cell Hypoxia / Q000187:drug effects; D002460:Cell Line; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008168:Lung / Q000187:drug effects / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D010641:Phenotype; D010766:Phosphorylation / Q000187:drug effects; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism / Q000473:pathology; D037721:Pulmonary Surfactant-Associated Protein C / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D015415:Biomarkers; D037721:Pulmonary Surfactant-Associated Protein C; D014409:Tumor Necrosis Factor-alpha; D048031:JNK Mitogen-Activated Protein Kinases
keywords: TNF-α; c-Jun N-terminal kinase; lung; matrix remodeling