Limosilactobacillus reuteri Alleviates Anxiety-like Behavior and Intestinal Symptoms in Two Stressed Mouse Models.

Background/objectives: Limosilactobacillus (Lm.) reuteri is a widely utilized probiotic, recognized for its significant role in alleviating symptoms associated with gastrointestinal and psychiatric disorders. However, the effectiveness of Lm. reuteri is strain-specific, and its genetic diversity leads to significant differences in phenotypes among different strains. This study aims to identify potential probiotic strains by comparing the strain-specific characteristics of Lm. reuteri to better understand their efficacy and mechanisms in alleviating stress-induced anxiety-like behaviors and gastrointestinal symptoms.

Methods: We cultivated 11 strains of Lm. reuteri from healthy human samples and conducted phenotypic and genomic characterizations. Two strains, WLR01 (=GOLDGUT-LR99) and WLR06, were screened as potential probiotics and were tested for their efficacy in alleviating anxiety-like behavior and intestinal symptoms in mouse models subjected to sleep deprivation (SD) and water avoidance stress (WAS).

Results: The results showed that the selected strains effectively improved mouse behaviors, including cognitive impairment and inflammatory response, as well as improving anxiety and regulating gut microbiota composition. The improvements with WLR01 were associated with the regulation of the NLRP3 inflammasome pathway in the SD model mice and were associated with visceral hypersensitivity and intestinal integrity in the WAS model mice.

Conclusions: In summary, this study identified the Lm. reuteri strain WLR01 as having the potential to alleviate anxiety-like behavior and intestinal symptoms through the analysis of Lm. reuteri genotypes and phenotypes, as well as validation in mouse models, thereby laying the foundation for future clinical applications.