PirB protects rat against hyperoxia-induced acute lung injury through inhibiting inflammation

PirB plays an important role in the immune system and is associated with bacterial infections and TNF-alpha expression. However, the contribution of pulmonary PirB to hyperoxic-induced acute lung injury (HALI) remains undefined. In this study, we established hyperoxic-induced acute lung injury model in rats and used hematoxylin and eosin (H&E) staining for lung injury assessment. Pulmonary PirB expression was determined by Western blotting and immunochemistry staining at different time points after hyperoxic treatment. Intravenously injection of p-PirB/cationic liposome complex was employed to over-expression of PirB in the lungs with HALI in rats. The lung injury and related cytokine expression was assessed by H&E staining and ELISA separately. Our results indicated that pulmonary PirB expression was significantly suppressed in the rats with HALI. Intravenously injection of p-PirB/cationic liposome complex dramatically increased PirB expression in the lungs, prolonged the survival time and ameliorated lung injury of rats with HALI. The related pro-inflammatory cytokine IL-6 and TNF-alpha expression in the lungs was significantly down-regulated by PirB. Collectively, our study suggested that PirB has a protective role against HALI and provided a novel target for HALI therapy.