Sex-Dependent Microbial and Host Profiles Following Fecal Microbiota and Bifidobacterium longum Treatment in Stress-Induced Gut Dysbiosis

Background/Aims: BBH016 in male and female Wistar rats subjected to repeated water avoidance stress. Methods: Fecal pellet output (FPO), colonic mast cell infiltration, and fecal short-chain fatty acids were measured. Gut microbial composition and function were analyzed by 16S rRNA sequencing and Kyoto Encyclopedia of Genes and Genomes pathway prediction. Results: appeared exclusively in stressed males. Functional predictions revealed the enrichment of estrogen signaling and bile acid pathways in males and the attenuation of proinflammatory pathways in females following LFM. Correlations between microbial taxa and host outcomes were predominantly observed in male rats. Conclusions: These findings highlight sex-specific microbial and host responses to microbiota-targeted therapies in a stress-induced IBS model, emphasizing sex as a biological variable in designing personalized microbiome-based treatments.