Fibulin-1 regulates the pathogenesis of tissue remodeling in respiratory diseases

Abstract

Airway and/or lung remodeling, involving exaggerated extracellular matrix (ECM) protein deposition, is a critical feature common to pulmonary diseases including chronic obstructive pulmonary disease (COPD), asthma, and idiopathic pulmonary fibrosis (IPF). Fibulin-1 (Fbln1), an important ECM protein involved in matrix organization, may be involved in the pathogenesis of these diseases. We found that Fbln1 was increased in COPD patients and in cigarette smoke-induced (CS-induced) experimental COPD in mice. Genetic or therapeutic inhibition of <i>Fbln1c</i> protected against CS-induced airway fibrosis and emphysema-like alveolar enlargement. In experimental COPD, this occurred through disrupted collagen organization and interactions with fibronectin, periostin, and tenascin-c. Genetic inhibition of <i>Fbln1c</i> also reduced levels of pulmonary inflammatory cells and proinflammatory cytokines/chemokines (TNF-α, IL-33, and CXCL1) in experimental COPD. <i>Fbln1c^-/-</i> mice also had reduced airway remodeling in experimental chronic asthma and pulmonary fibrosis. Our data show that Fbln1c may be a therapeutic target in chronic respiratory diseases.