Non-targeted metabolomics reveals the metabolic atlas of macrophages remodeled by SVPLA2 in Naja atra venom.

Snake venom phospholipase A2 (SVPLA2) is a key toxic component of Naja atra (N. atra) venom, yet its systematic impact on macrophage metabolism remains elusive. Using non-targeted metabolomics, combined with multivariate statistics and KEGG pathway enrichment, this study delineated the metabolic reprogramming of RAW 264.7 macrophages induced by SVPLA2 in N. atra venom and assessed the reversal effects of the specific inhibitor varespladib. SVPLA2 was associated with a a triple metabolic phenotype in macrophages: massive production of histamine and arachidonic acid derivatives, activating inflammatory lipid pathways; marked elevation of acylcarnitines, indicating disturbed fatty acid β-oxidation; and coordinated downregulation of de novo pyrimidine synthesis intermediates, leading to nucleotide starvation. Varespladib intervention effectively reversed the elevation of these inflammatory mediators and acylcarnitines and partially restored uridine levels. KEGG analysis further confirmed the involvement of arachidonic acid metabolism, PPAR signaling, peroxisome, and pyrimidine metabolism pathways. This study expands the functional role of SVPLA2 from conventional membrane phospholipid hydrolysis to the regulation of the macrophage metabolic reprogramming associated with inflammatory, energy-related, and pyrimidine metabolic pathways, providing a new insight for understanding snake venom pathogenesis.