Maresin 1 Maintains the Permeability of Lung Epithelial Cells In Vitro and In Vivo.

Previous reports showed that Maresin 1 (MaR1) possessed organ protection effects and could attenuate acute lung injury. Here, we aim to figure out whether MaR1 can maintain the permeability of lung epithelial cells by regulating the expression of tight junction protein during lung injury. Monolayer of murine lung epithelial cells was stimulated by lipopolysaccharide (LPS) with or without MaR1 and the permeability was evaluated. The expression of Claudin-1 and ZO-1 in lung epithelial cells was analyzed by immunofluorescence staining and western blotting. MaR1 was given to the mice after LPS induced acute lung injury. The permeability of lung was assessed by Evans Blue extravasation, lung wet/dry ratio and protein concentration in bronchoalveolar lavage fluid. Lung injury score was also evaluated. The expression of Claudin-1 and ZO-1 in the lung was analyzed by immunofluorescence staining. Results showed that MaR1 maintained the permeability of lung epithelial cells and upregulated the expression of Claudin-1 and ZO-1 after LPS stimulation. In acute lung injury mice, MaR1 upregulated the expression of Claudin-1 and ZO-1, decreased lung permeability, and reduced lung injury. In summary, this study suggests that MaR1 can maintain the permeability of lung epithelial cells by upregulating the expression of Claudin-1 and ZO-1 in acute lung injury.