Bifidobacterium bifidum FB3-12 attenuates ovalbumin-induced allergic diseases by enhancing intestinal barrier...

The escalating environmental changes have exacerbated the physiological suffering and economic burden caused by allergic diseases worldwide. Bifidobacterium bifidum (B. bifidum), due to its positive regulatory effects on the gut microenvironment, is considered a promising strategy for the prevention and treatment of allergies. Our study utilized the ovalbumin (OVA)-induced allergy mouse model to explore the anti-allergic potential of the self-screened strain B. bifidum FB3-12 (FB3-12) via intestinal intervention. The results demonstrated that a three-week FB3-12 treatment effectively suppressed the levels of immune markers, including OVA-specific immunoglobulin E (OVA-sIgE), mast cell protease-1 (Mcpt-1), and histamine (HIS) in the serum of allergic mice, and restored the Th2/Th1 immune response imbalance in the spleen. Furthermore, compared to the OVA group, FB3-12 intervention ameliorated intestinal damage and inflammation, significantly increasing the relative expression of Mucin-2 and tight junction proteins. Analysis of the gut microbiota profile revealed a distinct shift in the enterotype of OVA-challenged mice, characterized by a decreased Firmicutes/Bacteroidetes (F/B) ratio and a marked increase in the relative abundance of Akkermansia. FB3-12 intervention significantly enriched beneficial genera such as Lactobacillus and Colidextribacter, and upregulated the levels of short-chain fatty acids (SCFAs) and associated G protein-coupled receptors (GPRs) in the intestine. These findings underscore the therapeutic potential and application value of FB3-12 in alleviating allergic diseases through modulation of the gut microbiome.