Lethal concentration of perfluoroisobutylene induces acute lung injury in mice mediated via cytokine storm, oxidative stress and apoptosis

Perfluoroisobutylene (PFIB) is a highly toxic gas that targets the lungs. Low-level inhalation of the gas can lead to acute lung injury (ALI), pulmonary edema and even death. No specific anti-PFIB drugs are currently available and the pathogenesis of PFIB-induced ALI is not fully understood. Early direct oxidative injury and a secondary hyper-inflammatory response are recognized as the primary mechanisms of PFIB-induced ALI. In the present study, our data demonstrate for the first time that a cytokine storm is associated with PFIB-induced ALI. Levels of 10 pro-inflammatory cytokines and one anti-inflammatory cytokine were significantly increased in lung tissues of PFIB-exposed mice. PFIB inhalation additionally led to significant oxidative stress in lung tissue. Inflammation-associated CD11b(+)Ly6G(+)Ly6C(int) neutrophils and CD11b(+)Ly6G(-)Ly6C(hi) monocytes were significantly increased in blood in association with PFIB-induced ALI. Bcl-2/Bax-mediated lung cell apoptosis was significantly increased at 1h, followed by a sustained decrease after 1h, which was significant at 4-8h in PFIB-exposed mice. This suppression of apoptosis is possibly associated with the Akt-signaling pathway.