Fibroblast growth factor 18 alleviates hyperoxia-induced lung injury in mice by adjusting oxidative stress and inflammation.

OBJECTIVE Bronchopulmonary dysplasia (BPD) is one of the most common chronic lung diseases in infants, but the ways to prevent and treat BPD are still very limited. We tried to find an effective method for treating BPD by studying the effect of fibroblast growth factor 18 (FGF18) on hyperoxia-induced lung injury in mice. MATERIALS AND METHODS We placed newborn mice in high-oxygen environment (60-70%) and collected mouse lung tissue for histological examination at 3, 7, 14 and 21 days after birth. The correlation between FGF18 and BPD was studied by analyzing the expression of FGF18 in mouse lung tissue. In addition, we used exogenous FGF18 to stimulate primary mouse type II alveolar epithelial cells (AECs II), and detected changes in oxidative stress, inflammation and NF-κB signaling pathway activity of AECs II to analyze the effects of FGF18 on AECs II. RESULTS From the 7th day after the birth of the mouse, the lung tissue of the hyperoxia-induced mice suffered significant lung injury relative to the control group. The expression of FGF18 in lung tissue induced by hyperoxia was lower than that in the control group. Cell viability of AECs II stimulated by exogenous FGF18 increased, and FGF18 also reduced oxidative stress and inflammation levels of AECs II and inhibited the AECs II injury caused by hyperoxia. NF-κB signaling pathway activity in hyperoxia-induced lung increased, while exogenous FGF18 could reduce the expression and phosphorylation of NF-κB p65 in AECs II. CONCLUSIONS Hyperoxia-induced lung injury was accompanied by a decrease in FGF18. FGF18 can reduce oxidative stress and inflammation levels of AECs II by inhibiting the NF-κB signaling pathway, thereby reducing hyperoxia-induced cell injury.