Overview
- A study published June 10 in Cell Host & Microbe reported that systemic liraglutide reduced depressive‑like behavior in mice and that those benefits persisted in animals lacking the canonical GLP‑1 receptor.
- The team traced the effect to the gut microbiome, where liraglutide boosted bacterial biosynthesis of serine and phosphoenolpyruvate, allowing Lactobacillus delbrueckii to expand.
- Increased L. delbrueckii raised production of diacylglycerol and the endocannabinoid 2‑arachidonoylglycerol (2‑AG), and gut‑derived 2‑AG normalized stress‑induced hyperactivity in the basolateral amygdala and dorsomedial hypothalamus.
- Antibiotic depletion of gut microbes blocked liraglutide’s antidepressant effects, supporting a causal microbiota–endocannabinoid pathway, but the findings come from male mice and may not translate directly to humans.
- Because GLP‑1 agonists are already widely used for diabetes and obesity, authors say the result opens a path for drug repurposing and probiotic strategies, but they stress the need for replication and clinical trials to test safety, dosing, and relevance in people.