This study aimed to evaluate the effects of Bifidobacterium breve CCFM683 on psoriasis and to investigate the underlying mechanisms. Bifidobacterium breve CCFM683 significantly ameliorated psoriasis in mice as well as elevated the deoxycholic acid (DCA) and lithocholic acid (LCA) in the colon compared with those of the imiquimod-treated mice. Meanwhile, B. breve CCFM683 increased the relative abundance of DCA-producing Lachnoclostridium and diminished the harmful Desulfovibrio and Prevotellaceae UCG001. Additionally, the farnesoid X receptor (FXR) in the skin was activated and the expression of the TLR4/NF-κB pathway was inhibited, and the downstream IL-17 and TNF-α were downregulated whereas IL-10 was up-regulated . Moreover, the subsequent hyperproliferation of keratinocytes and the dysfunction of the epidermal barrier were improved. In conclusion, CCFM683 administration ameliorated IMQ-induced psoriasis via modulating gut microbiota, promoting the DCA production, regulating the FXR-TLR4/NF-κB pathway, diminishing proinflammatory cytokines, and regulating keratinocytes and epidermal barrier. These findings may be conducive to elucidating the mechanism for probiotics to ameliorate psoriasis and to promote its clinical trials in skin disease.

This study endeavors to investigate the effects of Bifidobacterium breve CCFM1078 on bone formation and resorption balance in growing BALB/c mice. Newborn BALB/c mice were assigned to the control group (administration saline) and the CCFM1078 group (administration B. breve CCFM1078, 3 × 10⁹ CFU/day) in 3-, 4-, and 5-week tests. All the groups have male and female distinctions. Our findings demonstrate that B. breve CCFM1078 exerts on the dynamic equilibrium between bone formation and resorption during the critical period of growth in mice by modulating the composition of gut microbiota and metabolites (hexadecanamide, linoleoyl ethanolamide, and palmitoyl ethanolamide), the genes and proteins expression related to the GH/IGF-1 axis and Gs/PKA/CREB signaling pathways, as well as downstream osteogenic and osteoclastic differentiation factors. The effects of B. breve CCFM1078 were different with age and gender dependent. This finding suggests B. breve CCFM1078 may have potential applications in regulating bone metabolism in the growth period population.

Bifidobacterium longum subsp. infantis is a commensal bacterium that predominates in the infant gut, playing a critical role in both preventing foreign infections and facilitating immune development. This study aimed to explore the effects of B. longum subsp. infantis supplementation on interferon-beta (IFN-β) secretion and intestinal barrier improvement in growing mice. Female and male mice were orally administered either saline or B. longum subsp. infantis CCFM1269 or I5TI (1 × 10⁹ CFU/mice per day, n = 8) from 1-week-age until 3-, 4-, and 5-week-age. RNA sequencing analysis revealed that CCFM1269 exhibited potential antiviral capacity through increasing 2’-5’ oligoadenylate synthetase (OAS). Additionally, CCFM1269 supplementation significantly increased colonic IFN-β levels which combined with OAS in 3-week-old female and male mice by activating the TLR4-TRIF-dependent signaling pathway. However, this effect was not observed in 4- and 5-week-old mice. Furthermore, both CCFM1269 were found to modulate the gut microbiota composition and enhance the intestinal barrier function in 3-, 4-, and 5-week-old mice. In summary, the results of this study suggested that B. longum subsp. infantis CCFM1269 promoting intestinal barrier and releasing IFN-β in growing mice was in a strain-specific and time-dependent manner.

Lactobacillus are considered promising therapeutic methods for nonalcoholic fatty liver disease (NAFLD). The effects of two strains of Limosilactobacillus mucosae on NAFLD were investigated in this study. Four-week-old male C57BL/6J mice were divided into 4 groups (n = 8 per group, Control, Model, FZJTZ26M3, FGSYC17L3). L. mucosae FZJTZ26M3 reduced the mice’s body weight, liver weight, and adipose tissue weight after 12 weeks of therapy. According to serum analysis, total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol significantly decreased after L. mucosae FZJTZ26M3 intervention. Liver pathology showed that L. mucosae FZJTZ26M3 was effective to ameliorate lipid deposition in NAFLD mice. Additionally, the expression of the gene related to lipid metabolism in the liver and adipose tissue was analyzed, and the results indicated that L. mucosae FZJTZ26M3 could alleviate NAFLD by regulating lipid metabolism. Furthermore, the results of 16S rRNA gene sequencing revealed a drop in the relative abundance of Ruminococcaceae, which is linked to inflammation, but the relative abundance of a potential probiotic Akkermansia significantly increased after L. mucosae FZJTZ26M3 intervention. Generally, L. mucosae FZJTZ26M3 could be a candidate to prevent NAFLD.