Potentiation of antidepressant effects: NPY1R agonist and ketamine synergy enhances TrkB signaling and neurogenesis in the ventral hippocampus.

A combination of an NPY1R agonist and Ketamine, given together to rodents, produced stronger antidepressant-like effects than either drug alone. The animals showed less immobility in a forced swimming test, a standard measure of antidepressant activity. This behavioral change was linked to increased formation of NPY1R/TrkB receptor complexes and higher levels of brain-derived neurotrophic factor (BDNF) in the ventral dentate gyrus of the hippocampus, along with increased neurogenesis. The results suggest that co-activating NPY1R and TrkB pathways may represent a novel therapeutic strategy for major depressive disorder that warrants further clinical investigation.

Study at a glance

Abstract

Major Depressive Disorder (MDD) poses a significant challenge to global health, with current treatments often limited by efficacy and onset delays. This study explores the synergistic antidepressant-like effects of an NPY1R agonist and Ketamine, targeting their neurobiological interactions within the ventral hippocampus. Utilizing a preclinical model, this study administered Neuropeptide Y receptor 1 (NPY1R) agonist and Ketamine, both separately and in combination, through intracerebroventricular (icv) and intranasal (i.n.) routes. The Forced Swimming Test (FST) was employed to assess antidepressant-like activity, while in situ Proximity Ligation Assay and immunohistochemistry were used to examine NPY1R/TrkB heteroreceptor complexes and BDNF expression in the ventral dentate gyrus (DG), along with neurogenesis markers. The combined treatment significantly reduced immobility in the FST, indicative of enhanced antidepressant-like effects, correlated with increased formation of NPY1R/TrkB complex and brain-derived neurotrophic factor (BDNF) expression in the ventral DG. These molecular alterations were associated with increased neurogenesis. The coadministration of an NPY1R agonist and Ketamine in a rodent model demonstrated potentiated antidepressant responses through synergistic neurobiological pathways, including TrkB signaling and hippocampal neurogenesis. This indicates a novel therapeutic strategy for MDD, warranting further clinical investigation to fully understand its implications.