Recent studies have indicated that dysfunction of gut microbiota, living microorganisms of the digestive tract, plays a role in the pathogenesis of neurodegenerative disorders, indicating the valuable impact of probiotics as a potential preventive or therapeutic strategy. Saccharomyces boulardii is a yeast probiotic with beneficial effects on various disorders, ranging from inflammatory gastrointestinal diseases to brain and behavioral disorders. Herein, we examined the effect of S. boulardii on memory impairment induced by lipopolysaccharide (LPS) in Wistar rats. Four groups of rats were used in this study (N = 10): (1) control [Cnt], (2) LPS, (3) LPS + S. boulardii [LPS + S], and (4) S. boulardii [S]. Animals were orally administered S. boulardii (250 mg/rat) or saline by gavage for 4 weeks. From the 14th day of the study, animals were administered intraperitoneal LPS (0.25 mg/kg/day) or saline for 9 days. We assessed memory impairment, neuroinflammation, and amyloid-β deposition. S. boulardii ameliorated LPS-induced memory dysfunction. We observed that S. boulardii significantly reduced the elevated levels of serum interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, as well as hippocampal levels of NLRP3 and caspase-1 in the LPS model. Moreover, S. boulardii alleviated amyloid-β deposition in the rat hippocampus. Collectively, our findings indicated that S. boulardii could inhibit memory impairment, neuroinflammation, and amyloid-β accumulation induced by LPS, possibly by modifying the gut microbiota.
Keywords: NLRP3; Saccharomyces boulardii; amyloid-β; lipopolysaccharide; neuroinflammation; probiotic.