γδTreg/γδTh17 Cell Imbalance Drives Xanthine-Mediated Metabolic Dysfunction in Restraint Stress-Induced Anxiety-Like Behavior

Abstract

Anxiety disorder is a highly prevalent psychiatric disorder, yet the role of γδT17/γδTreg-mediated metabolism in its pathogenesis remains unclear. We employed chronic restraint stress (RS) to establish an anxiety-like behavior mouse model and assessed behavioral changes. LC-MS/MS was employed to analyze the serum metabolomics of mice. RS mice were intraperitoneally injected with xanthine and brain tissue was taken for immunofluorescence. Here, Nissl staining and behavioral experiments respectively confirmed the neuronal pathology and behavioral alterations in RS mice. Flow cytometry and immunofluorescence revealed a significant imbalance in γδT17 and γδTreg cell populations in RS mice, characterized by an increase in γδT17 cells accompanied by a decrease in γδTreg cells. Deprivation of γδT17 cells using an αIL-17 antibody significantly ameliorated anxiety-like behavior in RS mice, whereas γδTreg cells deprivation using an αFoxP3 antibody exacerbated anxiety in RS mice. Metabolomic profiling identified profound alterations in the serum metabolic landscape of RS mice, particularly in purine and nucleotide metabolism pathway. Among the differentially abundant metabolites, xanthine and hypoxanthine were significantly increased in RS mice, and γδT17 cell depletion reversed these elevations. Exogenous xanthine administration exacerbated neuronal damage in RS mice, while immunofluorescence confirmed that xanthine primarily affects neurons rather than astrocytes. ELISA demonstrated that xanthine crosses the blood–brain barrier and accumulates in the brains of RS mice. Collectively, this study identifies a novel γδT17/γδTreg–xanthine axis linking immune dysregulation and metabolic reprogramming to anxiety-like behavior, providing new mechanistic insights and potential therapeutic targets for anxiety disorders.