MCC950, a NLRP3 inhibitor, ameliorates lipopolysaccharide-induced lung inflammation in mice.

Acute respiratory distress syndrome/chronic obstructive pulmonary disease (ARDS/COPD) is a diffuse inflammatory injury of the lung that is characterized by respiratory distress and vascular leakage and is caused by various factors. Although the treatment strategy for ARDS/COPD continues to be improved, it still lacks effective drugs. MCC950 is a potent and selective inhibitor ofthe nucleotide-binding oligomerization domain-like-receptor family pyrin domain-containing 3 (NLRP3) inflammasome. However, there have been no reports on the effects of MCC950 on lipopolysaccharide (LPS)-induced lung inflammation in mice. The objective of the present study was to evaluate the effects of MCC950 (given either intranasally or intraperitoneally) on inhibiting LPS-induced lung inflammation in mice. Acute lung inflammation was induced by intratracheal administration of LPS in ICR mice. The results showed that MCC950 at 50 mg/kg efficiently suppressed neutrophil lymphocytes (p < 0.001) and macrophage accumulation (p < 0.01) in bronchoalveolar lavage fluid (BALF) in LPS-instilled mice. In addition, hematoxylin and eosin (H&E) staining revealed that MCC950 at 50 mg/kg significantly inhibited pathological progress in the lung tissues (p < 0.01). Furthermore, treatment with MCC950 substantially reduced mRNA expression of IL-1β, IL-8, TGF-β1, and MMP-9 and also reduced protein levels of IL-1β, IL-18 and caspase-1 at 24 h after LPS instillation. The results of the present study indicate that MCC950 effectively inhibits LPS-induced lung inflammation in vivo, which can be considered for clinical translation.