Researchers found that a gut‑derived chemical called hippuric acid can fix social behavior problems in mice that lack normal gut bacteria, and it does this by raising oxytocin levels in the brain. While this shows a link between gut microbes, hippuric acid, and oxytocin, it’s still an early‑stage mouse study and not a ready‑to‑use protocol for people.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder typically characterized by impaired social communication. Previous reports have postulated gut microbiota to be an important non-genetic factor affecting ASD-like phenotypes in mice, as germ-free (GF) mice show impaired social communication. In this study, we identified hippuric acid (HA) as a metabolite generated via a gut microbiome-dependent mechanism that plays a role in the acquisition of social behavior during mouse development. We discovered that oral or intraperitoneal HA administration to GF mice normalizes their social behavior. Furthermore, HA administration restored oxytocin expression in the hypothalamic paraventricular nucleus and secretin expression in the subfornical organ, suggesting that HA may activate the secretin-oxytocin system to influence the social behavior of mice. These findings indicate that HA may serve as an important gut microbiome-dependent mediator affecting the brain mechanisms involved in regulating social behavior.