LGALS3 regulates endothelial-to-mesenchymal transition via PI3K/AKT signaling pathway in silica-induced pulmonary fibrosis

Silicosis is a progressive and chronic occupational lung disease characterized by lung inflammation, silicotic nodule formation, and diffuse pulmonary fibrosis. Emerging evidence indicates that endothelial-mesenchymal transition (EndoMT) plays a crucial role in the development of silicosis. Herein, we conducted a SiO₂-induced EndoMT model and established a mouse model with pulmonary fibrosis by silica. We identified that SiO₂ effectively increased the expression of mesenchymal markers while decreasing the levels of endothelial markers in endothelial cells. It’s further demonstrated that SiO₂ induced the PI3K/Akt signaling pathway activation via LGALS3 synthesis. Next, interfering LGALS3 blocked the process of EndoMT by inhibiting the activity of PI3K/AKT signaling. In vivo, the administration of a specific PI3K inhibitor LY294002 significantly alleviated silica-induced pulmonary fibrosis. Collectively, these results identified that the LGALS3/PI3K/AKT pathway provided a rationale target for the clinical treatment and intervention of silicosis.