Polyethylene glycol loxenatide reduces NETosis and immunofluorescence hyperactivation in Behçet's disease.

BACKGROUND: Neutrophil hyperactivation, particularly through the release of neutrophil extracellular traps (NETosis), plays a crucial role in driving vascular inflammation in Behçet's disease (BD). While pyroptosis has been linked to the pathogenesis of BD, the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on neutrophil dysregulation have not been previously explored. METHODS: We investigated the effects of polyethylene glycol loxenatide (PEX168) on neutrophil activation using neutrophils isolated from BD patients, LPS-stimulated neutrophils from healthy donors, and a murine model of BD. We employed a variety of techniques, including western blotting, flow cytometry for reactive oxygen species (ROS) detection, immunohistochemistry on oral mucosa, colon, and pericardial vessels, transmission electron microscopy for cellular ultrastructure, and immunofluorescence to evaluate NETosis, pyroptosis, and inflammasome activation. RESULTS: PEX168 significantly and dose-dependently reduced neutrophil hyperactivation, decreasing NETosis markers (CitH3, NE, MPO) and ROS. It preserved cellular ultrastructure by mitigating mitochondrial swelling and chromatin margination. While higher concentrations inhibited the NLRP3-caspase-1-IL-1β pathway, PEX168 did not induce pyroptosis, as uncleaved GSDMD-N' remained nuclear. Low concentrations transiently enhanced IL-1β secretion, indicating biphasic immunomodulation via NF-κB. CONCLUSION: PEX168 attenuates neutrophil hyperactivation and NETosis in Behçet's disease via ROS suppression and upstream inflammasome regulation, disrupting inflammatory signaling without provoking pyroptosis. These findings support GLP-1 RAs as a targeted treatment for neutrophil-driven autoimmune disorders.