Saccharomyces boulardii attenuates lipopolysaccharide-induced anxiety-like behaviors in rats

Anxiety is the brain's response to dangerous or stressful situations. Exposure to stressors can cause gut microbiota dysbiosis and activate the hypothalamic-pituitary-adrenal (HPA) axis, leading to the secretion of glucocorticoids associated with anxiety. Recent studies have reported that probiotics can attenuate anxiety-like behaviors by modulation of the gut microbiome composition. The present study aimed to investigate the effects of Saccharomyces boulardii (Sb) administration on anxiety-like behaviors induced by lipopolysaccharide (LPS) in rats. The animals were randomly divided into four groups (Control, LPS, Sb + LPS, and Sb). All animals were orally treated with saline or S. boulardii (1010 CFU/ml/rat) for 28 days. They were also injected with saline or LPS (250 mu g/kg/ day) intraperitoneally from day 14 until day 22. Anxiety-like behaviors were assessed using the elevated plus maze and open-field tests. Besides, the serum levels of cortisol, corticosterone, serotonin, and brain-derived neurotrophic factor (BDNF) were measured. The results revealed that S. boulardii could attenuate LPS-induced anxiety-like behaviors. The findings also showed that oral administration of S. boulardii significantly attenuated the elevated levels of cortisol and corticosterone in the LPS-induced model. Moreover, S. boulardii alleviated the decremental effect of LPS on the serum serotonin and BDNF levels. According to the present findings, S. boulardii can prevent LPS-induced anxiety-like behaviors, probably through modulation of the HPA axis and the gut microbiome.

Automated summary

Anxiety is the brain's response to dangerous or stressful situations. Exposure to stressors can cause gut microbiota dysbiosis and activate the hypothalamic-pituitary-adrenal (HPA) axis, leading to the secretion of glucocorticoids associated with anxiety. Recent studies have reported that probiotics can attenuate anxiety-like behaviors by modulation of the gut microbiome composition. The present study aimed to investigate the effects of Saccharomyces boulardii (Sb) administration on anxiety-like behaviors induced by lipopolysaccharide (LPS) in rats. The results revealed that S. boulardii could attenuate LPS-induced anxiety-like behaviors, probably through modulation of the HPA axis and the gut microbiome. Oral administration of S. boulardii significantly attenuated the elevated levels of cortisol and corticosterone in the LPS-induced model, and also alleviated the decremental effect of LPS on the serum serotonin and BDNF levels.