The role of WNT/b-catenin signaling in smooth muscle cells during lung development and repair

Abstract

Wnt signaling is important for the formation of different organs during embryonic development. It also plays a key role in lung development, as it is required for branching morphogenesis, proliferation, differentiation and survival of lung progenitors in both the epithelium and mesenchyme. Upregulation of Wnt signaling in the mesenchymal cells is associated with lung pathologies, such as asthma, lung fibrosis, and pulmonary arterial hypertension. After naphthalene injury, an established mouse model of airway epithelial damage, the surviving ciliated airway epithelial cells express Wnt7b. Wnt7b then acts on parabronchial smooth muscle cells (PBSMCs) to induce Fibroblast Growth Factor 10 (Fgf10) expression leading to the expansion of epithelial progenitor cells required for epithelial restoration after injury.