Advances on role of Wnt signaling pathway in airway epithelial damage induced by air polluton and its repair

The adverse effect of air pollution on respiratory system has raised public concern. In general, respiratory tract is the major route of air pollutant into the human body, accompanying with oxidatve stress and inflammatory response. As the frst line of defense against air pollutants, a normal functioning airway epithelium can repair the damage caused by air pollutants immediately to maintain respiratory health. Alteration or dysfunction of the epithelial repair ability might link to further respiratory damage and even respiratory disease. The Wnt signaling pathway partcipates in the development and progression of several respiratory diseases such as chronic obstructve pulmonary disease (COPD) and asthma. Previous studies have reported that it is a critcal pathway related to cell self-renewal and respiratory damage and repair, and includes canonical Wnt/β-catenin pathway and non-canonical Wnt pathway, two pathways with different functions. The canonical Wnt pathway participates in cell adhesion to maintain the integrity of the airway epithelium and to promote epithelial repair; the Wnt5a release stmulated by air pollutants can cause inflammaton by actvatng the non-canonical Wnt pathway, and also reduce epithelium repair capacity through inhibitng the canonical Wnt pathway. Both pathways partcipate in the process of epithelium repair, and imbalance of epithelial repair process may lead to related respiratory diseases. This artcle comprehensively reviewed current research on the role of Wnt signaling pathway in the airway epithelial damage induced by air polluton and epithelial repair, aiming to provide insights for the preventon and control of respiratory diseases induced by air polluton.