Chaetocin attenuates gout in mice through inhibiting HIF-1α and NLRP3 inflammasome-dependent IL-1β secretion in macrophages.

Chaetocin is a fungal metabolite that possesses a potential anti-inflammatory activity. Acute gout is a self-limiting inflammatory response to monosodium urate (MSU) crystals. However, the effect of cheatocin on gout has not been elucidated. In the study, we found that chaetocin could decrease MSU induced IL-1β secretion in bone marrow derived macrophages by several mechanisms, including inhibiting the activation of NLRP3 inflammasome. Chaetocin negatively regulated apoptosis-associated speck-like protein with a CARD domain oligomerization, and caspase-1 processing, key events during inflammasome activation. Furthermore, chaetocin restrain expressions of Hypoxia-inducible factor-1α and Hexokinase 2, mediators of glycolysis, which necessary for synthesis of pro-IL-1β during inflammasome priming. In vivo, chaetocin ameliorate MSU-induced arthritis, which showed as reduced local swelling and inflammatory cell infiltration. In MSU-induced peritonitis model, the peritoneal macrophages of chaetocin-pretreated mice showed significantly decreased mRNA levels of HIF-1α and NLRP3 related genes. These findings suggested that chaetocin has a potent anti-inflammatory effect against gout. More importantly, it is proposed that the inhibiting of glycolysis pathway would be a new avenue for the treatment of gout flare and other IL-1β related diseases.