Exploring role of Bacillus coagulans BCP92™ (MTCC 25460) in modulation of depressive-like behavior: Unraveling microbiome gut-brain axis

Abstract

Background: Recent findings indicate that gut microbiota can significantly impact cognitive health. In this study, we explored the effects of Bacillus coagulans (Heyndrickxia coagulans) BCP92™ on depression-like behaviors using maternal separation and the chronic unpredictable mild stress model.

Methods: Depression in rats was induced through maternal separation followed by chronic unpredictable mild stress. B. coagulans BCP92™ was administered to the rats at a dose of 2 billion CFU for six weeks. Depression-like behaviors were assessed using the sucrose preference test, forced swim test, elevated plus maze test, and open-field test. After the treatment period, the animals were sacrificed, and brain, intestine, and fecal samples were collected for biochemical, molecular, and histopathological analyses.

Results: B coagulans BCP92™ mitigated depressive behaviors as evidenced by improvements in the behavior assessments. The treatment related changes in levels of neurotransmitters such as noradrenaline, dopamine, serotonin, and brain-derived neurotrophic factor while reducing pro-inflammatory markers like C-reactive protein, TNF-α, and IL-1β in the brain. Additionally, B. coagulans BCP92™ administration restored levels of BDNF, doublecortin, GFAP, and zona occludens in the brain, suggesting a neuroprotective effect. An increased ratio of Firmicutes to Bacteroidetes, along with higher levels of short-chain fatty acids in fecal samples, was observed. Histopathological analysis indicated that both brain and intestinal structures were preserved, demonstrating the maintenance of their integrity.

Conclusion: The findings from this study suggest that B. coagulans BCP92™ exerts antidepressant effects by modulating the gut-brain axis, thereby remodeling gut microbiota and promoting neurobehavioral health.

Keywords: Bacillus coagulans; Depression; Gut Microbiome-brain axis; Microbiome; Neuroprotection; Probiotic.