Aerobic glycolysis promotes NLRP3 inflammasome activation via NLRP3 lactylation.

Bacteria-infected macrophages undergo pyroptosis to release inflammatory cytokines, which contributes to host defense. It has been known that activated macrophages involve metabolic reprogramming. However, the metabolic changes and the role of metabolites in pyroptotic macrophages are not fully understood. Here, we revealed that aerobic glycolysis product, lactate, could promote NLRP3 inflammasome activation induced pyroptosis. We found that endogenous lactate facilitates ASC recruitment to NLRP3 cores on the organelle membrane, thus inducing NLRP3 inflammasome complex formation. Mechanistically, we identified NLRP3 as a target protein modified by lactate, which is lactylated by AARS2. We confirmed lactylated sites on NLRP3 by LC-MS/MS analysis and verified that lactylation at K24 and K565 of NLRP3 facilitates inflammasome activation in macrophage. In vivo, inhibition of lactate production alleviates inflammatory responses in polymicrobial sepsis. Overall, our results indicate the role of lactate in regulating macrophage pyroptosis and the crosstalk between metabolism and innate immunity.