Epigenetic-metabolic regulation of macrophage pyroptosis by FTO-m6A-NLRP3 axis: insights from multi-omics analysis

Sepsis, a severe illness marked by immune dysregulation and widespread inflammation, involves macrophage pyroptosis as a key player. This study explores the impact of RNA N6-methyladenosine (m 6 A) modification and investigates whether fat mass and obesity-associated protein (FTO)-mediated demethylation influences macrophage pyroptosis by modulating NOD-like receptor protein 3 (NLRP3) inflammasome activation. The research aims to unravel the workings of the FTO-m 6 A-NLRP3 pathway in macrophage pyroptosis and assess the therapeutic potential of targeted intervention using biomimetic nanovesicles. Results:By developing CD11b/CD206 dual-ligand modified macrophage-derived small extracellular vesicle (sEV)-biomimetic nanovesicles loaded with FB23-2, an FTO inhibitor (FB23-2-loaded Dual-Vesicles) and employing various molecular techniques, including MeRIP-qPCR, WB, scRNA-seq, spatial transcriptomics, and metabolomics, the study delves into the mechanism by which FTO-regulated m 6 A modification impacts NLRP3 inflammasome and inflammatory metabolic pathways. Findings reveal upregulated FTO levels in septic macrophages, reduced m 6 A modification levels, and increased expression of NLRP3 and interleukin-1 beta (IL-1β). Treatment with an FTO inhibitor increased m6A modification of Il1b mRNA, reduced IL-1β expression, and attenuated NLRP3 inflammasome activation and pyroptosis-associated changes. FB23-2-loaded Dual-Vesicles showed enhanced macrophage uptake and pulmonary enrichment, improved 7-day survival, and reduced inflammatory injury in murine models. Conclusions: These findings support further evaluation of the FTO-m6A-NLRP3-pyroptosis regulatory network as a targeted epigenetic intervention strategy in sepsis and related inflammatory diseases.