GW117 induces anxiolytic effects by improving hippocampal functions

GW117 functions as both an MT1/MT2 receptor agonist and a 5-HT2C receptor antagonist. This study aimed to investigate the anxiolytic effects of GW117 through behavioral assessments, including the open field test and novelty-suppressed feeding test (NSFT) within a chronic unpredictable mild stress (CUMS) model. GW117 was administered via oral gavage for 21 days to evaluate its sustained anxiolytic effects, with behavioral tests including the NSFT, the Vogel-conflict test, and the O-maze test. To explore the underlying mechanisms, we performed Western blot analyses to assess the expression levels of BCL2-Associated X (Bax), cleaved caspase-3, B-cell lymphoma-2 (Bcl-2), brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP). Additionally, BrdU labeling and immunofluorescence staining were used to examine changes in neuronal regeneration and astrocytogenesis. Our results demonstrated that GW117 produced significant anxiolytic effects across all behavioral assays, both in the CUMS model and during long-term administration. Mechanistic studies revealed that GW117 notably increased the expression of BDNF, GFAP, and Bcl-2, while reducing Bax and cleaved caspase-3 levels in the hippocampus of CUMS model rats. Furthermore, the populations of BrdU-positive and GFAP-positive cells were elevated. These findings suggest that GW117 exerts anxiolytic effects, potentially through enhancements in hippocampal function.