Protective effect of zerumbone reduces lipopolysaccharide-induced acute lung injury via antioxidative enzymes and Nrf2/HO-1 pathway

Acute lung injury (ALI) is a serious disease with high morbidity and mortality rate. Although there are effective strategies for treatment of ALI; a widely accepted specific pharmacotherapy has not yet established. Zerumbone, the major active phytochemical compound from Zingiber zerumbet Smith, exhibits various beneficial biological and pharmacological activities, such as antioxidation, anti-inflammation, immunomodulation, and anti-cancer. We aimed to study the potential protective effects and mechanisms of zerumbone in mouse model of lipopolysaccharide (LPS)-induced ALI. Pretreatment with zerumbone inhibited the histopatholgical changes such as neutrophils infiltration, increased in alveolar barrier thickness, hemorrhage, and hyaline membrane formation occurred in lungs in LPS-induced ALI. In addition, not only LPS-induced activation of myeloperoxidase (MPO) and metallopeptidase-9 (MMP-9) was suppressed by zerumbone, but also lipid peroxidation in lungs was inhibited as well. Moreover, pretreatment with zerumbone reversed the antioxidative enzymes activities, including superoxide dismutase, catalase, and glutathione peroxidase, decreased by LPS and enhanced the expression of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase (HO-1) induced by LPS. These results from present study suggested that the protective mechanisms of zerumbone on LPS-induced ALI were via up-regulation of antioxidative enzymes and Nrf2/HO-1 pathway.