Glycolytic reprogramming governs crystalline silica-induced pyroptosis and inflammation through promoting lactylation modification

Abstract

Prolonged inhalation of environmental crystalline silica (CS) can cause silicosis, characterized by persistent pulmonary inflammation and irreversible fibrosis, but the mechanism has not been elucidated. To uncover the role and underlying mechanism of glycolytic reprogramming in CS-induced pulmonary inflammation, the mouse silicosis models and glycolysis inhibition models were established in vivo. And the CS-induced macrophage activation models were utilized to further explore the underlying mechanism in vitro. The results showed that CS induced lung inflammation accompanied by glycolytic reprogramming and pyroptosis. The application of glycolysis inhibitor (2-DG) suppressed CS-induced pyroptosis and alleviated lung inflammation. In vitro, 2-DG effectively impeded CS-induced macrophage pyroptosis and inflammatory response. Mechanistically, 2-DG suppressed pyroptosis by inhibiting NLRP3 inflammasome activation both in vivo and in vitro. Furtherly, metabolite lactate facilitated NLRP3-dependent pyroptosis synergistically with CS particles, while blocking the source of lactate largely alleviated NLRP3 inflammasome activation and subsequent pyroptosis triggered by CS. More profoundly, the increment of lactate induced by CS might drive NLRP3-dependent pyroptosis by increasing histone lactylation levels. In conclusion, our findings demonstrated inhibiting glycolytic reprogramming could alleviate CS-induced inflammatory response through suppressing NLRP3 -dependent pyroptosis. Increased glycolytic metabolite lactate and protein lactylation modifications might represent significant mechanisms during CS-induced NLRP3 activation and macrophage pyroptosis.

Keywords: Crystalline silica; Glycolytic reprogramming; Lactate; Lactylation; Lung inflammation; Pyroptosis.