Semaglutide attenuates neuroinflammation in male mice.

Abstract

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have shown promise in preclinical models of neurodegeneration, with emerging evidence suggesting these effects may be driven by modulation of neuroinflammation. However, the cellular mechanisms underlying GLP-1RA effects on neuroinflammation remain poorly understood. Here we show, using a mouse model of lipopolysaccharide-induced neuroinflammation, how semaglutide coordinates cellular responses to resolve neuroinflammation. We find that semaglutide in male mice prevents brain infiltration of neutrophils, excessive cytokine release, and suppresses neuroinflammation-associated transcriptional signatures specifically in microglia, endothelial cells, and a subset of pericytes. Mechanistically, we identify a subset of Glp1r-expressing neurons in the dorsal vagal complex that, upon semaglutide treatment, regulate genes involved in anti-inflammatory signaling. Semaglutide-modulated pathways overlap with inflammatory signatures found in human neurodegenerative diseases, including Alzheimer's disease, suggesting broad relevance for conditions involving neuroinflammation. Together, these findings reveal how GLP-1R signaling in male mice orchestrates resolution of neuroinflammation through coordinated multi-cellular programs.