Liraglutide attenuates lipopolysaccharide-induced acute lung injury in mice

Liraglutide, an effective drug for the treatment of diabetes, has been proven to demonstrate anti-inflammatory and immunomodulatory effects. Hence, this study explored the effects and mechanism of action of liraglutide on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. Male BALB/c mice were pre-conditioned with liraglutide or saline prior to intraperitoneal LPS or saline administration. Histopathological examination of lung, the wet/dry (W/D)weight ratio, protein content, inflammatory cell numbers and pro-inflammatory cytokine levels in broncho-alveolar lavage fluid (BAL fluid) were conducted. The effects of liraglutide on the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome signalling pathway were assessed by Western blot. Pre-treatment with liraglutide decreased the wet-to-dry weight ratio and protein concentrations in BAL fluid and neutrophil infiltration in the lung tissues. Liraglutide also significantly reduced the interleukin-1β and interleukin-18 levels in BAL fluid, as well as effectively inhibited the expression of NLRP3 inflammasome. These results indicated that liraglutide pre-treatment attenuated LPS-induced ALI by inhibiting the NLRP3 inflammasome pathway.