Neurobiological effects of a probiotic-supplemented diet in chronically stressed male Long-Evans rats: Evidence of enhanced resilience

• DOI: 10.1016/j.ibneur.2021.10.004
• Publication Date: 2021-11-06T16:10:05Z
• Authors: Nick R. Natale; Molly Kent; Nathan Fox; Dylan Vavra; Kelly Lambert
• Keywords: Basolateral amygdala; Corticosterone; Environmental Enrichment; Elevated plus maze; Chronic Stress

Probiotics that regulate the microbiome-gut-brain axis and provide mental health benefits to host are referred as psychobiotics. Preclinical studies have demonstrated psychobiotic effects on early life stress-induced anxiety- depression-related behavior in rodents; however, specific mechanisms remain ill-defined. In current study, we investigated of probiotic supplementation neurobiological responses chronic stress adult male Long-Evans rats. Twenty-four rats were randomly assigned (PB) or vehicle control (VEH) groups, then either unpredictable (CUS) no-stress (CON) conditions within each group (n = 6/subgroup). We hypothesized PB would reduce markers anxiety enhance emotional resilience, especially CUS animals. cognitive uncertainty task, a nonsignificant trend was observed indicating PB-supplemented animals spent more time oriented toward food reward than VEH open-field CUS-PB center arena CUS-VEH animals, an effect not between two CON groups. swim regardless assignment, exhibited increased floating, suggesting conserved response challenging context. Focusing endocrine measures, higher dehydroepiandrosterone (DHEA)-to-corticosterone fecal metabolite ratios, correlate Further, reduced microglia immunoreactivity basolateral amygdala, possibly neuroprotective supplements this rodent model. These results evidence interacts with exposure influence adaptive associated endocrine, neural, behavioral indices anxiety.