Sulforaphane attenuates phosgene-induced acute lung injury via the Nrf2-HO-1/NQO1 pathway

Sulforaphane (SFN) has been demonstrated to exert a protective role in various diseases. However, the role of SFN in phosgene-induced acute lung injury (P-ALI) remains unclear. This study aimed to explore the role and mechanism of SFN in P-ALI and provide a theoretical basis for the clinical prevention and treatment of P-ALI.

A mouse model of P-ALI was established followed by phosgene gas inhalation at a dose of 4.17 g/m³ for 5 min. The survival rate, lung coefficient and hematoxylin and eosin (H&E) staining, lung pathology scoring, and bronchoalveolar lavage fluid (BALF) analysis were performed to evaluate lung tissue damage. The real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting analysis were utilized to evaluate the relative expression levels of inflammation factors and protein expression.

Compared with the control group, destruction of alveolar structure, pulmonary edema, lung tissue inflammation and oxidative stress occurred after phosgene exposure. After the administration of SFN, the massive exudation of red blood cells and significant thickening of alveolar interstitium were ameliorated, the lung tissue inflammation was improved, and oxidative stress level was reduced. Mechanically, SFN could increase the expression of nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2) protein and the downstream heme oxgenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1), thereby improving P-ALI. And the Nrf2 inhibitor ML385 attenuated the lung protective effect of SFN.

Phosgene inhalation led to edema, inflammation, and oxidative stress of lung tissue in mice. SFN might ameliorate phosgene-induced lung injury through Nrf2-HO-1/NQO1 signaling pathway.