A microbiota-tryptophol-AhR axis mediates the gut-kidney protective effects of Hushen Tongfengtai Granules in hyperuricemic nephropathy.

Bifidobacterium breve is a dominant member of the infant gut microbiota and is widely recognized for its probiotic attributes, including carbohydrate metabolism, stress tolerance, and pathogen inhibition. In this study, we sequenced the whole genome of B. breve NCIM 5671 to assess its metabolic potential, adaptive traits, safety, and antimicrobial activity. We assembled the genome into 69 contigs totaling 2.41Mb, with a GC content of 58.5%, and it encodes 2,189 genes. Functional annotation revealed a high abundance of genes involved in amino acid and carbohydrate metabolism. Pan-genome analysis of 50 B. breve genomes revealed an open pan-genome structure with 976 core genes and significant accessory and strain-specific gene diversity. Phylogenetic and ANI analyses placed NCIM 5671 within a clade of infant-derived strains. Notably, we identified multiple antimicrobial peptide biosynthetic gene clusters, including lanthipeptide and lasso peptide systems, some of which were previously reported in B. breve but remain functionally uncharacterized. In vitro analysis confirmed the production of a low-molecular-weight peptide with broad-spectrum antimicrobial activity, specifically inhibiting RNA biosynthesis, consistent with the known mechanism of lasso peptides. Safety assessment revealed no functional antibiotic resistance or virulence genes. Overall, this study establishes an integrated genomic and functional framework for elucidating strain-specific probiotic traits in NCIM 5671. Importantly, this is the first study to functionally explore a putative lasso peptide-associated antimicrobial system in B. breve.

Bifidobacterium breve is a key early life gut colonizer with important physiological functions; however, functional genomic studies in this species are hindered by the lack of robust genetic tools. In this study, we employed RNA-seq to identify endogenous constitutive promoters from B. breve CCFM683. Two of these promoters exhibited significantly higher activity than the reference promoter in a single-fluorescence reporter assay. Further analysis using a dual-fluorescence system revealed that one promoter also possesses bidirectional activity. Rational engineering generated four promoter variants with substantially enhanced activity. Subsequent sequence analysis identified conserved regions within the core promoter sequences of B. breve. Finally, cross-species evaluation in heterologous bifidobacteria identified one promoter with the broadest applicability. Collectively, this study provides a suite of broadly applicable promoter tools for genetic functional studies and heterologous gene expression in B. breve and related species.

Advocating gut-retina connection and microbiota mediated pathways in management of age-related macular degeneration: Preclinical to clinical perspective.

Probiotic combinations affect characteristics of chickpea yogurt: an investigation on physicochemical, rheological, and organoleptic properties and SCFAs fermentation.

Human milk oligosaccharides (HMOs) are abundant and structurally diverse glycans that shape the development of infant gut microbiota. Yet, how individual HMOs and bacterial genes drive the community assembly remain elusive. Here, we reconstructed an eight-member infant Bacterial Community (iBaCo) from representing dominant taxa in human infant feces. When individual HMOs were the sole carbohydrate source, they showed deterministic effects on the iBaCo composition and metabolic output. Notably, the tetramer HMO lacto-N-tetraose (LNT), in spite of its identical monomer composition as lacto-N-neotetraose (LNnT), showed a strong effect on maintaining Bifidobacterium breve abundance in iBaCo, whereas LNnT did not. Monoculture growth profiling, proteomics, enzymatic kinetic assay, and molecular docking revealed that β -galactosidase D4BMY8 and the relevant downstream pathways are induced by LNT and that D4BMY8 has substrate preference on LNT over LNnT, enabling a faster growth of Bi. breve and accumulation of acetate and lactate in LNT compared to LNnT. Metabolic flux analysis indicated that the substrate-preference of β -galactosidase D4BMY8 drives the skewed energy cost toward lactate/acetate metabolic output. Finally, the D4BMY8-encoding gene lacZ5 is widely spread in all isolated Bi. breve genomes, but divergently distributed in infant metagenome-assembled Bi. breve genomes. Together, we demonstrated that a single enzyme-substrate interaction could orchestrate the composition and metabolic function of an infant bacterial community, which may contribute to the assembly of dynamic infant gut microbiota. Our integrative approach provides a mechanistic framework for understanding the interaction between diet, microbial community, and infant gut health.

Structural investigation of polysaccharides extracted from four Bifidobacterium breve strains.

Coexisting strains of the same species within metagenomic data pose a substantial challenge to inferring transmission of pathogenic and commensal microbes. Here we present TRAnsmission Clustering of Strains (TRACS), a highly accurate algorithm for estimating genetic distances between strains at the level of individual single nucleotide polymorphisms, which is robust to intra-species diversity within the host. Analysis of faecal microbiota transplantation datasets and extensive simulations demonstrates that TRACS outperforms existing methods. We use TRACS to infer transmission networks in patients colonized with multiple strains, including severe acute respiratory syndrome coronavirus 2 amplicon sequencing data, deep population sequencing data of Streptococcus pneumoniae and single-cell genome sequencing data from patients infected with Plasmodium falciparum. Applying TRACS to gut metagenomic samples from a mother-infant cohort revealed species-specific transmission rates and identified increased the persistence of Bifidobacterium breve in infants, a finding previously missed owing to the presence of multiple strains. Our study shows that TRACS can be used across microbial kingdoms to uncover strain dynamics.

The increasing prevalence of obesity worldwide has highlighted the need for adjunct strategies targeting metabolic dysfunction beyond simple weight reduction. This review aimed to evaluate the hypothesis that the anti-obesity effects of probiotics are mediated through modifications in fat distribution, metabolic inflammation, and appetite regulation rather than reductions in body weight or body mass index (BMI). A critical appraisal of recent randomized, double-blind, placebo-controlled human clinical trials was conducted, focusing on the effects of probiotic supplementation on adiposity, fat distribution, metabolic parameters, and eating behaviors. The evidence indicates that probiotic strains, particularly Lactobacillus gasseri and Bifidobacterium breve, are consistently associated with reductions in visceral fat, total body fat, waist circumference (WC), and body fat percentage, while effects on body weight and BMI remain modest. Strains of Lacticaseibacillus rhamnosus showed improvements in satiety. Probiotic supplementation with B. breve, B. pseudocatenulatum, L. plantarum Inducia were also linked to improvements in lipid metabolism, glucose homeostasis, inflammatory markers, and appetite regulation. Notably, several studies reported more pronounced effects in female participants. Overall, these findings suggest that probiotics exert anti-obesity effects primarily through metabolic and compositional changes rather than direct weight loss, supporting their role as a complementary strategy in obesity management.

Dietary supplement silver nanoparticles have recently drawn attention following reports of hazards associated with long-term use. However, their biosafety, especially their effects on the gut-brain axis, remains largely unexplored. This study demonstrated that dietary supplement silver nanoparticles can accumulate in the intestines, brain, and liver of mice. Chronic exposure to these nanoparticles leads to Alzheimer-like lesions, primarily by disrupting gut microbiota balance. Specifically, this exposure depletes Bifidobacterium and Ruminococcaceae, resulting in reduced intestinal metabolites such as sphingomyelin (d18:1/20:0), tryptophan, and indole. Consequently, this disruption causes neuroinflammation, cognitive impairment, and amyloid-β deposition in mice. Moreover, Bifidobacterium was identified as a key microbial group contributing to Alzheimer-like lesions after exposure, whereas supplementation with Bifidobacterium breve MCC1274 effectively alleviated these lesions. Therefore, the potential risks of silver nanoparticles in dietary supplements should be carefully evaluated. This study provides a promising new direction for the prevention and treatment of Alzheimer-like lesions through microbial interventions.

Constipation has emerged as an important public health concern, and novel therapeutic approaches, such as those, are attracting increasing attention. However, the effects and mechanisms of Bifidobacterium breve and lacto-N-neotetraose (LNnT) in relieving constipation remain incompletely understood. Moreover, the potential synergistic effects of B. breve and LNnT in alleviating constipation are still unclear. In this study, we used 4-wk-old female BALB/c mice (n = 60), which were randomly assigned to normal control (NC) group, model control (MC) group, LNnT group, B. breve group, and B. breve+LNnT group. We evaluated the effects of B. breve+LNnT on defecation performance and intestinal mucus secretion. We also analyzed gut microbiota composition and metabolic functions. Additionally, an independent cohort of 45 mice was used to assess the effect of gut microbiota and microbiota-derived metabolites on constipation. The results demonstrated that B. breve+LNnT increased the gastrointestinal transit rate and fecal water content while reducing whole-gut transit time. It also elevated serum concentrations of gastrin (GAS) and motilin (MLT) while decreasing those of vasoactive intestinal peptide (VIP) and nitric oxide (NO). Mice receiving B. breve+LNnT showed increased intestinal mucus content, a more organized mucus layer structure, and higher expression of mucus-related genes (Muc2, Agr2, Muc1, Muc4, Muc13). Additionally, B. breve+LNnT increased gut microbiota diversity and enriched potentially beneficial microbiota, including Ruminococcus, Bifidobacterium, Tyzzerella, and Roseburia. Consistently, levels of the acetate and propionate were elevated in the B. breve+LNnT group. Correlation analysis indicated positive associations between these microbiota and acetate. Finally, we explored the role of gut microbiota, acetate, and propionate in constipation. We found that the alleviation of constipation by B. breve+LNnT depended on the presence of gut microbiota and was associated with microbiota-derived acetate.

<em>Bifidobacterium breve</em> B2798 ameliorates high-fat diet-induced obesity by reshaping gut microbiota and modulating host metabolic profiles

While probiotics are widely recognized for their adjunctive benefits in ulcerative colitis treatment, the therapeutic potential of heat-killed cells remains underexplored. This study directly compared the efficacy of Bifidobacterium breve B2798 probiotics (LB group) and their heat-killed counterparts (DB group) in alleviating dextran sulfate sodium (DSS)-induced colitis in rats. Over a 21-day intervention, both treatments significantly mitigated colitis symptoms, including weight loss, colon damage, and splenomegaly, with heat-killed cells demonstrating superior histological improvement over live probiotics. Serum analysis revealed that both interventions normalized DSS-induced cytokine dysregulation, reducing pro-inflammatory markers and elevating anti-inflammatory. Although α-diversity remained stable, β-diversity analysis indicated distinct gut microbiota restructuring. Heat-killed cells uniquely enriched butyrate-producing Alistipes spp. and Parabacteroides distasonis, while probiotics upregulated Mucispirillum schaedleri and Odoribacter splanchnicus. Metabolomic profiling identified shared elevation of anti-inflammatory metabolites (linoleic acid, isorhamnetin) in both groups, yet heat-killed cells exhibited stronger modulation of metabolic pathways, including TCA cycle activation and pantothenate biosynthesis suppression. Correlation networks highlighted species-specific microbiota-metabolite-cytokine interactions, with Mucispirillum schaedleri and Barnesiella intestinihominis negatively associated with inflammatory markers (MPO, TNF-α). These findings demonstrate that while both live and heat-killed B. breve B2798 alleviate colitis, heat-killed cells exert enhanced regulatory effects on gut microbiota composition, metabolic pathways, and inflammatory responses, offering a safer alternative for inflammatory bowel disease management. Further mechanistic studies are warranted to validate these preclinical insights.

Dose-Related Alleviation of Cyclophosphamide-Induced Immunosuppression by Bifidobacterium breve CCFM1310: Involvement of Gut Barrier Restoration and Selective MAPK Subfamily Phosphorylation

Introduction. Bifidobacterium breve species have demonstrated potential therapeutic effects on acute diarrhea; however, supporting clinical evidence remains limited. This study evaluates the impact of a combination of Bifidobacterium breve BR03 and Bifidobacterium breve B632 on the clinical outcomes of children with acute diarrhea. Methods. This randomized, prospective study included children aged six months to five years at a tertiary care center. The intervention group received a probiotic formulation containing B. breve BR03 and B. breve B632 (five drops/day) alongside peroral zinc (15 mg/day) and oral rehydration solution (ORS) for five days. The control group received ORS and peroral zinc for the same duration. Results. Among the 120 enrolled children, 72 (60%) were boys. The median ages were 32.0 months (18.0–45.0) in the study group and 30.0 months (17.0–55.0) in the control group, with no significant differences in baseline characteristics. Stool frequency was significantly lower in the study group at 24–48 h (2.41 ± 1.99 vs. 3.07 ± 1.71, p = 0.020), 48–72 h (0.98 ± 1.31 vs. 1.90 ± 1.58, p < 0.001), and 72–96 h (0.44 ± 1.18 vs. 1.03 ± 1.35, p < 0.001). The proportion of children experiencing diarrhea at these intervals was also significantly lower in the probiotic group. Conclusion. The combination of B. breve BR03 and B. breve B632 significantly reduces stool frequency and diarrhea duration in children with acute diarrhea, supporting its potential as an adjunct therapy.

Probiotic fortification of plant-based foods has attracted significant interest due to its potential benefits for gut and metabolic health. However, maintaining adequate probiotic viability during processing and storage remains a key challenge, especially in non-dairy systems with low buffering capacity and limited nutrient composition. Walnut-based products represent a promising yet underexplored food matrix because they naturally provide unsaturated fatty acids, proteins, phenolic compounds, and bioactive peptides, which may support microbial survival and confer additional health benefits. Previous studies have indicated that under optimal fermentation conditions, several strains, including Lactiplantibacillus plantarum, Bifidobacterium breve, Lacticaseibacillus casei, Lacticaseibacillus rhamnosus, Streptococcus thermophilus, and Lactobacillus delbrueckii subsp. bulgaricus, can maintain viable cell counts above the functional threshold of 6 log CFU/ml in walnut-based matrices. This review synthesizes the current evidence on the use of walnut milk and walnut-based products as probiotic carriers and discusses how fermentation can be used to develop functional foods that consistently confer health benefits.

Atopic dermatitis (AD), a prevalent allergic skin disease characterized by a Th2-dominant inflammatory response, imposes a significant global health burden. Early-life serves as a pivotal period for intestinal microbial establishment, which critically influences immune system development and has lasting implications for health into later life. This study evaluated the therapeutic potential of early-life intervention with Bifidobacterium breve CCFM1078 on DNFB-induced atopic dermatitis in a murine model. Intervention with B. breve CCFM1078 significantly alleviated AD manifestations, such as ear swelling and epidermal hyperplasia. These improvements were associated with diminished inflammatory cell infiltration, lowered serum IgE levels, and reduced expression of key pro-inflammatory cytokines (IL-4, IL-13, CCL-22) in skin tissues, alongside elevated levels of IFN-γ and the anti-inflammatory cytokine IL-10. Additionally, the intervention boosted both IgA and secretory IgA (sIgA) levels in the colon. Mechanistically, B. breve CCFM1078 activated the aryl hydrocarbon receptor (AhR) signaling pathway, leading to the upregulation of CYP1A1, Gal-1, and Gal-3, and suppressed TSLP production. It also favorably altered gut microbiota composition by enriching beneficial bacterial taxa. In summary, early-life administration of B. breve CCFM1078 alleviates AD symptoms through concurrent modulation of the AhR pathway, restoration of Th1/Th2 immune balance, and beneficial restructuring of gut microbiota.

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. The gut microbiota exerts unique therapeutic advantages against CRC, and the probiotic Bifidobacterium breve (B. breve) has been extensively documented to suppress CRC initiation in murine models. Although the role of B. breve in CRC has been established, whether its extracellular vesicles (EVs), as key mediators of bacteria-host crosstalk, exert a functional impact remains undefined. Here, we aim to explore the therapeutic potential of B. breve-derived EVs (B.breEVs) and their active cargo, formate acetyltransferase (pflB), in CRC. Integrative analysis of the curated database of human gut metagenomes cohort (GMrepo) database and an MC38 subcutaneous tumor model revealed a significant reduction of B. breve abundance in faecal samples from CRC patients and tumor-bearing mice. Administration of live B. breve or its cell-free supernatant markedly inhibited tumor growth, whereas pasteurized bacteria or GW4869-mediated EVs blockade abolished this effect, indicating that EVs are the critical effector entities. Isolated B.breEVs selectively accumulated within tumor tissue, directly triggered apoptosis of colorectal cancer cells, and elevated the proportion of IFN-γ⁺ CD8⁺ cytotoxic T lymphocytes (CTLs) in tumor while concurrently ameliorating gut microbial structure and function. Mass-spectrometric profiling identified the pflB as an important active protein within B.breEVs. Recombinant pflB selectively inhibited MC38 cell viability in vitro and significantly reduced CRC burden in vivo. RNA sequencing of tumor issue demonstrated that pflB up-regulated granzyme B, perforin1 and CTL/NK-associated transcripts, and activated the intrinsic apoptotic pathway. Immuno-combination studies further revealed that pflB plus anti-PD1 therapy markedly increased the infiltration of CD8⁺ CTL and NK cells, and enhanced their cytotoxicity compared to either monotherapy. B. breve secretes pflB-loaded EVs that reshape the intestinal micro-ecology, activate CD8⁺ CTL/NK anti-tumor immunity, directly induce mitochondrial apoptosis in malignant cells, and enhance the effects of immune checkpoint blockers to overcome drug resistance, offering a precision "probiotic-EVs-active protein" triadic intervention strategy for CRC.

Chronic diarrhea is a common gastrointestinal disorder in young children, leading to nutritional deficiencies, growth retardation, and increased healthcare burdens. Gut microbiota dysbiosis is closely associated with the pathogenesis of chronic diarrhea, but the efficacy of probiotic-supplemented formula tailored to the intestinal microenvironment of Chinese children remains unclear. This study aims to evaluate the therapeutic effect of probiotic-supplemented formula on chronic diarrhea in children aged 6–43 months and explore its potential mechanism through gut microbiota analysis. This randomized, open-label controlled trial was conducted from September 1, 2024, to September 1, 2025, at two hospitals in Shantou City. A total of 160 children aged 6–43 months with chronic diarrhea were enrolled and randomized to the intervention group (n = 80) or control group (n = 80), with 129 participants ultimately included in the efficacy analysis. The intervention group received formula supplemented with Bifidobacterium breve (10 billion CFU/day) as the sole variable, while the control group received the identical formula without Bifidobacterium breve, with both groups consuming the formula for 1 month. The primary outcome was the 1-week cure rate, defined as cure (BSFS = 3,4) or ineffective (BSFS = 5,6,7); efficacy was quantified as the difference in cure rates between the intervention and control groups. Secondary outcomes included time to symptom resolution (diarrhea cessation, stool normalization), changes in fecal microbiota composition, and adverse events. The cure rate in the intervention group was significantly higher than in the control group (37.7% vs. 19.7%, relative risk [RR] = 1.91, 95% confidence interval [CI]:1.08–3.38, P = 0.013). Multivariable logistic regression showed the intervention group had significantly higher odds of efficacy after adjusting for confounders (adjusted odds ratio [OR] = 3.40, 95% CI:1.41–8.22, P = 0.006). Cox proportional hazards modeling indicated a 66% reduction in the risk of persistent diarrhea in the intervention group (hazard ratio [HR] = 0.34, 95% CI:0.21–0.53, P < 0.001). Gut microbiota analysis revealed the intervention group had enriched specific beneficial taxa without the reduction of pre-existing pathobionts. Probiotic-supplemented formula significantly accelerates the resolution of pediatric chronic diarrhea. Mechanistically, this efficacy is driven by specific commensal engraftment rather than mere pathobiont eradication, overcoming the persistent ‘dysbiotic lock’ to improve intestinal clinical outcomes.

Constipation affects about 25% of the general population, with higher prevalence in elderly people. Many of the products used for the treatment of constipation, laxatives and drugs with this indication have undesirable effects such as dehydration, electrolyte disturbances and diarrhea or side effects that, in frail patients with comorbidities, such as the elderly, can have clinically significant consequences. For these reasons, the treatment of chronic constipation constitutes, especially in the elderly patient, a partial unmet medical need. This interventional, single-arm pilot study evaluated efficacy and safety of a probiotic-prebiotic combination in elderly patients with chronic constipation. The probiotics included Lactobacillus rhamnosus, Lactobacillus paracasei, Bifidobacterium animalis ssp. lactis, and Bifidobacterium breve. Treatment lasted 28 consecutive days. Fifty elderly patients (average age 65.3 years) with chronic constipation participated. At baseline, 72% of patients reported ≤2 complete spontaneous bowel movements (CSBM) per week. After the treatment, 36% of patients reported ≤2 CSBMs/week (P=0.023), 64% experienced improvement of 1-4 CSBMs/week. Quality of Life (QoL) related to abdominal pain, bloating, and constipation improved. No adverse events were reported. This real-world study suggests that probiotic-prebiotic combinations can rapidly improve bowel transit and constipation symptoms, potentially reducing dependence on laxatives and enemas while improving QoL. A longer-term randomized controlled trial is needed to confirm these findings.