Deoxynivalenol induces macrophage extracellular trap formation via the PER2-c-Myc-ROS Axis.

Deoxynivalenol (DON), a Fusarium-derived mycotoxin, disrupts immune homeostasis and induces immunotoxicity. Macrophage extracellular traps (METs) are key effectors in innate immunity and inflammation, yet whether DON triggers METs formation and the underlying mechanisms remain unclear. This study aims to investigate the molecular mechanism by which DON induces METs generation through circadian rhythm immune checkpoints involving the PER2-c-Myc axis. Using RAW264.7 and THP-1 macrophage models, we combined siRNA-mediated Per2 knockdown, and pharmacological inhibitors to dissect the mechanisms of DON-induced METosis. We showed that DON (2-4 μM) triggered a biphasic METosis. The early phase (1-2 h) represents vital or non-suicidal METosis, characterized by F-actin depolymerization, rapid DNA release, and acute extrusion of MET markers histone H4, H2AX, CitH3, and MPO, reflecting an acute defense response. The late phase (8-12 h) corresponds to suicidal METosis, featuring a secondary surge in MET markers and typical reticular ultrastructures, indicating impaired repair and pathological progression. Mechanistically, DON co-activates an ROS-driven pathway and a PADI2-mediated histone modification pathway to drive suicidal METosis. PER2 acts as a circadian-immune checkpoint, positively regulating both pathways while suppressing c-Myc and maintaining its phosphorylation balance. In turn, c-Myc inhibits ROS signaling and MET release. Thus, DON-associated changes in PER2 expression, causing its aberrant upregulation, c-Myc suppression, and consequent derepression of ROS-driven METosis. This study elucidates a novel molecular mechanism by which DON promotes suicidal METosis in macrophages via the PER2-c-Myc-ROS signaling, providing new molecular targets for understanding DON-induced immunotoxicity.