Depressive-like behavior in male rats induced by repeated social defeat requires vagal signaling, suggesting gut-brain-axis crosstalk. In animals with an intact vagus nerve, oral administration of viable or inactivated B. salyersiae HB32 reversed behavioral changes induced by chronic stress at levels comparable to ketamine. Additionally, supplementation of HB32 and iHB32 was associated with attenuation of stress-related microbiome and prefrontal cortex transcriptional changes.
Dothard et al. (Tue,) studied this question.