Antiaging Effects of Human Fecal Transplants with Different Combinations of Bifidobacterium bifidum LTBB21J1 and Lactobacillus casei LTL1361 in d-Galactose-Induced Mice.

The feces of healthy middle-aged and old people were first transplanted into d-galactose-induced aging mice to construct humanized aging mice with gut microbiota (FMTC) to confirm the antiaging effect of probiotics produced from centenarians. The mouse model was then treated with centenarian-derived Bifidobacterium bifidum (FMTL), Lactobacillus casei (FMTB), and their mixtures (FMTM), and young mice were used as the control. Compared with the FMTC group, the results demonstrated that the probiotics and their combinations alleviated neuronal damage, increased antioxidant capacity, decreased inflammation, and enhanced cognitive and memory functions in aging mice. In the gut microbiota, the relative abundance of Lactobacillus, Ligilactobacillus, and Akkermansia increased and that of Desulfovibrio and Colidextribacter decreased in the FMTM group compared with that in the FMTC group. The three probiotic groups displayed significant changes in 15 metabolites compared with the FMTC group, with 4 metabolites showing increased expression and 11 metabolites showing decreased expression. The groups were graded as Control > FMTM > FMTB > FMTL > FMTC using a newly developed comprehensive quantitative scoring system that thoroughly analyzed the various indicators of this study. The beneficial antiaging effects of probiotics derived from centenarians were quantitatively described using a novel perspective in this study; it is confirmed that both probiotics and their combinations exert antiaging effects, with the probiotic complex group exhibiting a larger effect.

Probiotics induce intestinal IgA secretion in weanling mice potentially through promoting intestinal APRIL expression and modulating the gut microbiota composition.

Intestinal infections are strongly associated with infant mortality, and intestinal immunoglobulin A (IgA) is important to protect infants from intestinal infections after weaning. This study aims to screen probiotics that can promote the production of intestinal IgA after weaning and further explore their potential mechanisms of action. In this study, probiotics promoting intestinal IgA production were screened in weanling mouse models. The results showed that oral administration of Bifidobacterium bifidum (B. bifidum) FL228.1 and Bifidobacterium bifidum (B. bifidum) FL276.1 significantly enhanced IgA levels in the small intestine and upregulated the expression of a proliferation-inducing ligand (APRIL) and its upstream regulatory factor toll-like receptor 4 (TLR4). Furthermore, B. bifidum FL228.1 upregulated the relative abundance of Lactobacillus, while B. bifidum FL276.1 increased the relative abundance of Marvinbryantia and decreased Mucispirillum, further elevating intestinal IgA levels. In summary, B. bifidum FL228.1 and B. bifidum FL276.1 can induce IgA production in the intestinal tract of weanling mice by promoting intestinal APRIL expression and mediating changes in the gut microbiota, thus playing a significant role in enhancing local intestinal immunity in infants.

The Role of Bifidobacterium bifidum novaBBF7, Bifidobacterium longum novaBLG2 and Lactobacillus paracasei TJB8 to Improve Mechanisms Linked to Neuronal Cells Protection against Oxidative Condition in a Gut-Brain Axis Model.

Despite the identification of several innovative targets for avoiding cognitive decline, there has yet to be a widely accepted approach that deals with minimising the deterioration of cognitive function. In this light, recent studies suggest that regulating the gut-brain axis with probiotics is a potential therapeutic strategy to support brain health. For this reason, in vitro models were used to examine the efficacy of different probiotic combinations to enhance intestinal homeostasis and positively affect the brain. Therefore, the new formulation has been evaluated for its capacity to modify intestinal barrier functions in a 3D in vitro model without any adverse effects and directly impact the mechanisms underlying cognitive function in a gut-brain axis model. According to our findings, B. bifidum novaBBF7 10 mg/mL, B. longum novaBLG2 5 mg/mL and L. paracasei TJB8 10 mg/mL may successfully modify the intestinal barrier and improve SCFA production. Successively, the probiotics studied caused no harm at the neuronal level, as demonstrated by iNOS, mitochondrial potential, and cell viability tests, confirming their safety features and enhancing antioxidant mechanisms and antineuroinflammation activity. Additionally, the damage caused by oxidative stress was also healed, and critical pathways that result in cognitive impairment were changed by synergetic action, supporting the hypothesis that brain ageing and neurodegeneration are slowed down. All these findings demonstrate the ability of probiotics to affect cognitive processes and their ability to sustain the mechanisms underlying cognitive function by acting on intestinal function.

Bifidobacterium bifidum CCFM1163 Alleviated Cathartic Colon by Regulating the Intestinal Barrier and Restoring Enteric Nerves.

Cathartic colon (CC), a type of slow-transit constipation caused by the long-term use of stimulant laxatives, does not have a precise and effective treatment. This study aimed to evaluate the ability of Bifidobacterium bifidum CCFM1163 to relieve CC and to investigate its underlying mechanism. Male C57BL/6J mice were treated with senna extract for 8 weeks, followed by a 2-week treatment with B. bifidum CCFM1163. The results revealed that B. bifidum CCFM1163 effectively alleviated CC symptoms. The possible mechanism of B. bifidum CCFM1163 in relieving CC was analyzed by measuring the intestinal barrier and enteric nervous system (ENS)-related indices and establishing a correlation between each index and gut microbiota. The results indicated that B. bifidum CCFM1163 changed the gut microbiota by significantly increasing the relative abundance of Bifidobacterium, Faecalibaculum, Romboutsia, and Turicibacter as well as the content of short-chain fatty acids, especially propionic acid, in the feces. This increased the expression of tight junction proteins and aquaporin 8, decreased intestinal transit time, increased fecal water content, and relieved CC. In addition, B. bifidum CCFM1163 also increased the relative abundance of Faecalibaculum in feces and the expression of enteric nerve marker proteins to repair the ENS, promote intestinal motility, and relieve constipation.

Isolation and Characterization of Staphylococcus aureus from Raw Cow's Milk and Investigating the Effect of Bifidobacterium bifidum Probiotic Cell Free Supernatant on Their Enterotoxins Genes Expression.

The present reserach aimed to detect and isolate the genes involved in the staphylococcal enterotoxins (SEs) production in strains isolated from unprocessed cow's milk and to examine the impact of Bifidobacterium bifidum probiotic cell-free supernatant (CFS) on their expression. Standard techniques were used for isolation and identification of Staphylococci strains in unprocessed milk. The PCR was used to identify strains carrying enterotoxin genes. The B. bifidum CFS was applied to strains containing the target genes, and the genes expression levels were quantified using Real-time PCR. Using 16SrDNA sequencing, the phylogenic relationship of the isolated strains was determined. Analysis revealed that bacteria such as Staphylococcus species were found in the 72% of the samples. The PCR test showed the presence of various SE superantigens, including SEA (16.7%), SEC (11.7%), SED (8.3%), SEE (6.7%), and SEB (1.7%) in isolated strains. The B. bifidum CFS had obvious antimicrobial activity against strains 24, 51, 54, and 35 of Staphylococcus species, and the minimum inhibitory concentration and minimum bactericidal concentration values for these strains treated with B. bifidum CFS were in the range of 31.25-125 µg/ml. Strains 51 and 24 were clustered with S.aureus ATCC 25923, and strains 54 and 35 were clustered with S.aureus ATCC 12600, respectively. The RT-PCR exhibited that probiotics CFS suppressed the expression of SEA, SEB, SEC, and SEE genes (P<0.05). The average fold change for SEA, SEB, SEC, and SED genes was -1.681, -1.28, -1.52, and -0.84, respectively. The research demonstrated that probiotic bacteria can lower enterotoxin production by downregulating the expression of SEs genes.

[Protective effect and mechanism of Bifidobacterium bifidum TMC3115 on long-term colitis in mice which exposed to antibiotic in early life].

OBJECTIVE: To explore the protective effect and mechanism of Bifidobacterium bifidum TMC3115 of improving the gut microbiota disorder caused by antibiotic exposurein early life, and the possible protection of inflammatory bowel disease in adulthood in mice. METHODS: 80 newborn mice were randomly divided into 3 groups, a blank control group(n=40), a ceftriaxone exposure group(n=20), a Bifidobacterium bifidum TMC3115 intervention group(n=20). After birth, they were respectively treated with saline, ceftriaxone(100 mg/kg), and ceftriaxone(100 mg/kg) + TMC3115(1×10~9CFU/d) for 3 weeks. After 3 weeks, half of each group was randomly sacrificed, and the rest were normally fed to 6 weeks. At 6 weeks, the blank control group was randomly divided into a negative control group(n=10) and a colitis model group(n=10). The negative control group drunk pure water freely, and the other three groups were added 3% DSS to the drinking water for 4 days to induce colitis. At 6 weeks and 4 days, the remaining mice were sacrificed. The weight change, spleen coefficient, gut microbiota analysis based on second-generation sequencing and serum tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-10(IL-10)levels of the mice at 3 weeks and after DSS intervention were recorded. In addition, the colon length and inflammation pathology score of the mice after DSS intervention were also measured. RESULTS: At 3 weeks, compared with the control, antibiotic exposure in the early life inhibited the weight gain and reduced the diversity and uniformity of the gut microbiota of the mice(P<0.05). The intervention of TMC3115 under antibiotic exposure during this period increased the relative abundance of Bifidobacterium in the intestines(P<0.05), and the effect still existed after DSS stimulation in adulthood, laying the foundation for TMC3115 to exert long-term benefits. After DSS stimulation in adulthood, mice showed significant weight gain inhibition, colon length shorteningand inflammation pathology scoreincrease compared with the negative control(P<0.05), showed the inflammatory bowel disease(IBD)model was successfully constructed. The relative abundance of beneficial bacteria such as Lactobacillus in the Bifidobacterium bifidum TMC3115 intervention group increased compared with the ceftriaxone exposure group(P<0.05), while the relative abundance of harmful bacteria such as Staphylococcus, Clostridium, and Desulfovibrio decreased(P<0.05). Furthermore, the mice exposed to antibiotic in early life produced a stronger immune response, but the mice which received TMC3115 intervention at the same time had a significant decrease in serum TNF-α and IL-6 levels and increase in IL-10 level compared with the mice which only interfered with antibiotics(P<0.05). CONCLUSION: Antibiotic exposure in early life is a negative factor for long-term inflammatory bowel disease, and TMC3115 has preventive significance for long-term inflammatory bowel disease under the background of antibiotic exposure. The mechanism of TMC3115 may be to adjust the gut microbiota and balance the immune system.

Microbial and metabolic profiles of bronchopulmonary dysplasia and therapeutic effects of potential probiotics Limosilactobacillus reuteri and Bifidobacterium bifidum.

AIMS: Bronchopulmonary dysplasia (BPD) is a common respiratory disease in newborns; however, there is no effective treatment. We aimed to investigate the effects of the potential probiotics Limosilactobacillus reuteri and Bifidobacterium bifidum on BPD using 16S rDNA sequencing and metabolomics methods. METHODS AND RESULTS: Faecal samples were collected from 10 BPD patients and 10 healthy subjects. 16S rDNA sequencing results showed that microbial diversity was decreased and compositions were affected in BPD. Escherichia-Shigella and Clostridium_sensu_stricto_1 were increased in the BPD group, and Enterobacteriaceae, Megamonas, Blautia, Lactobacillus (Limosilactobacillus), [Eubacterium]_coprostanoligenes_group, Phascolarctobacterium and Bifidobacterium were reduced. Metabolomics analysis identified 129 differentiated metabolites that were changed in BPD patients, and they were associated with a preference for carbohydrate metabolism in translation and metabolism during genetic information processing. Correlation analysis revealed a remarkable relationship between gut microbiota and metabolites. Subsequently, a BPD cell model was constructed to test the effect of the potential probiotics. Cell function experiments verified that treatment with the potential probiotics L. reuteri and B. bifidum promoted proliferation and inhibited apoptosis of hyperoxia-induced MLE-12 cells. In addition, treatment with the potential probiotics L. reuteri and B. bifidum reduced inflammation and oxidative stress damage. CONCLUSIONS: Treatment with the potential probiotics L. reuteri and B. bifidum could alleviate BPD and reduce inflammation and oxidative stress damage. SIGNIFICANCE AND IMPACT: This study was the first to report positive roles for the potential probiotics L. reuteri and B. bifidum in BPD. The potential probiotics L. reuteri and B. bifidum were shown to reduce inflammation and oxidative stress damage in BPD. This study provided new insights on the pathogenesis and treatment of BPD.

Effect of Probiotic Bifidobacterium bifidum TMC3115 Supplementation on Psychosocial Stress Using a Sub-Chronic and Mild Social Defeat Stress in Mice.

With the accumulation of knowledge on the relation between psychological stress and gut microbiota, there is growing interest in controlling stress and/or mood disorders via probiotic supplementation. We aimed to examine the effect of probiotic Bifidobacterium bifidum TMC3115 (TMC3115) supplementation using a sub-chronic and mild social defeat stress murine model in this study. TM3115 supplementation maintained body weight gain and alleviated a polydipsia-like symptom induced by the stress. In the analyses of fecal and cecal bacterial profiles, expansions of Proteobacteria in stressed mice and increases in Actinobacteria and Bifidobacterium in mice supplemented with TMC3115 were observed. There was no marked difference in the diversity of cecal bacteria between the tested mice. Elevated serum levels of inflammatory markers such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 were observed in the stressed mice, while TMC3115 only reduced the IL-6 level. These findings suggest that TMC3115 supplementation confers tolerance to psychosocial stress in the host through modulation of the gut microbiota and alleviation of stress-induced inflammatory responses. Furthermore, it may be expected to exert prevention and treatment of disorders related to peripheral IL-6, including depression.

Genome Features of Probiotic Bifidobacteria Determining Their Strain-Specific Properties.

The aim of the study was to analyze the genome features of the probiotic strains Bifidobacterium longum 379, Bifidobacterium bifidum 1, and Bifidobacterium bifidum 791 and study their antiviral activity. Materials and Methods: Whole genome sequencing of three strains of bifidobacteria was performed on the MiSeq platform (Illumina Inc., USA). The genomes were annotated using the Prokka v. 1.11 utility and RAST genomic server. The individual genetic determinants were searched using the ResFinder 3.2, PathogenFinder, PlasmidFinder, RAST, and Bagel 4 software. The antiviral activity of the strains against influenza A viruses was studied using MDCK cells (Madin-Darby canine kidney cells), the epidemic strain of influenza A/Lipetsk/1V/2018 (H1N1 pdm09) (EPI_ISL_332798), the highly pathogenic avian influenza virus A/common gull/Saratov/1676/2018 (H5N6) strain (EPI_ISL_336925), and neutral red vital dye. Results: The genomes of all studied strains contained determinants responsible for utilization of carbohydrates of plant origin; the genes of key enzymes for the synthesis of tryptophan and folic acid are present in the genomes of B. longum 379 and B. bifidum 791. A feature of the B. bifidum 791 genome is the presence of determinants responsible for the synthesis of thermostable type I bacteriocins - flavucin and lasso peptide. The B. bifidum 791 strain was found to show pronounced antiviral activity against both the strains of influenza A, the supernatant of which suppressed viral replication in vitro up to a dilution of 1:8, and the cells inhibited viral reproduction up to a concentration of 6·106 CFU/ml. Conclusion: The analysis of complete genomes of B. longum 379, B. bifidum 1, and B. bifidum 791 showed features that determine their strain-specific properties, the findings on which were previously made empirically based on indirect signs. In the genomes of B. longum 379 and B. bifidum 791 strains, in contrast to B. bifidum 1 strain, key enzymes for the synthesis of tryptophan and folic acid were found. These substances have an impact on the human body in many ways, including having a thymoleptic effect (reducing emotional stress, irritability, anxiety, eliminating lethargy, apathy, melancholy, anxiety) and regulating cognitive activity. The presence of determinants responsible for the synthesis of thermostable type I bacteriocins in the genome of B. bifidum 791 strain determines its pronounced antiviral activity.

Bifidobacterium bifidum Enhances the Intestinal Epithelial Tight Junction Barrier and Protects against Intestinal Inflammation by Targeting the Toll-like Receptor-2 Pathway in an NF-κB-Independent Manner.

Defective intestinal tight junction (TJ) barrier is a hallmark in the pathogenesis of inflammatory bowel disease (IBD). To date, there are no effective therapies that specifically target the intestinal TJ barrier. Among the various probiotic bacteria, Bifidobacterium, is one of the most widely studied to have beneficial effects on the intestinal TJ barrier. The main purpose of this study was to identify Bifidobacterium species that cause a sustained enhancement in the intestinal epithelial TJ barrier and can be used therapeutically to target the intestinal TJ barrier and to protect against or treat intestinal inflammation. Our results showed that Bifidobacterium bifidum caused a marked, sustained enhancement in the intestinal TJ barrier in Caco-2 monolayers. The Bifidobacterium bifidum effect on TJ barrier was strain-specific, and only the strain designated as BB1 caused a maximal enhancement in TJ barrier function. The mechanism of BB1 enhancement of intestinal TJ barrier required live bacterial cell/enterocyte interaction and was mediated by the BB1 attachment to Toll-like receptor-2 (TLR-2) at the apical membrane surface. The BB1 enhancement of the intestinal epithelial TJ barrier function was mediated by the activation of the p38 kinase pathway, but not the NF-κB signaling pathway. Moreover, the BB1 caused a marked enhancement in mouse intestinal TJ barrier in a TLR-2-dependent manner and protected against dextran sodium sulfate (DSS)-induced increase in mouse colonic permeability, and treated the DSS-induced colitis in a TJ barrier-dependent manner. These studies show that probiotic bacteria BB1 causes a strain-specific enhancement of the intestinal TJ barrier through a novel mechanism involving BB1 attachment to the enterocyte TLR-2 receptor complex and activation of p38 kinase pathway.

Integration of Transcriptome and Metabolome Reveals the Genes and Metabolites Involved in Bifidobacterium bifidum Biofilm Formation.

Bifidobacterium bifidum strains, an important component of probiotic foods, can form biofilms on abiotic surfaces, leading to increased self-resistance. However, little is known about the molecular mechanism of B. bifidum biofilm formation. A time series transcriptome sequencing and untargeted metabolomics analysis of both B. bifidum biofilm and planktonic cells was performed to identify key genes and metabolites involved in biofilm formation. Two hundred thirty-five nonredundant differentially expressed genes (DEGs) (including vanY, pstS, degP, groS, infC, groL, yajC, tadB and sigA) and 219 nonredundant differentially expressed metabolites (including L-threonine, L-cystine, L-tyrosine, ascorbic acid, niacinamide, butyric acid and sphinganine) were identified. Thirteen pathways were identified during the integration of both transcriptomics and metabolomics data, including ABC transporters; quorum sensing; two-component system; oxidative phosphorylation; cysteine and methionine metabolism; glutathione metabolism; glycine, serine and threonine metabolism; and valine, leucine and isoleucine biosynthesis. The DEGs that relate to the integration pathways included asd, atpB, degP, folC, ilvE, metC, pheA, pstS, pyrE, serB, ulaE, yajC and zwf. The differentially accumulated metabolites included L-cystine, L-serine, L-threonine, L-tyrosine, methylmalonate, monodehydroascorbate, nicotinamide, orthophosphate, spermine and tocopherol. These results indicate that quorum sensing, two-component system and amino acid metabolism are essential during B. bifidum biofilm formation.

Different Bifidobacterium bifidum strains change the intestinal flora composition of mice via different mechanisms to alleviate loperamide-induced constipation.

Constipation is a condition with a high prevalence rate worldwide and may occur in men and women of any age. Bifidobacterium bifidum has been shown to have a relieving effect on constipation, but the underlying mechanism is still unknown. This study explored the effects of gavage of three strains of B. bifidum (CCFM668, FHNFQ25M12 and FXJCJ32M2) from different sources in mice with loperamide-induced constipation. After 38 days of intervention, B. bifidum CCFM668, FHNFQ25M12 and FXJCJ32M2 showed the ability to modify the levels of gastrointestinal active peptides and promote the expression of 5-hydroxytryptamine (5-HT or serotonin) receptor 4 (5-HT4R), thereby promoting small intestinal peristalsis. The strains could also effectively increase the thickness of the colonic mucosa. However, what was different from previous studies was that these results were independent of the levels of short-chain fatty acids (SCFAs) and 5-HT. Further analysis of the intestinal flora revealed that the relative abundances of the genera Faecalibaculum and Ruminococcaceae_UCG_014 in the constipated mice increased significantly, whereas that of Erysipelatoclostridium decreased. A correlation analysis between the intestinal flora and evaluated gastrointestinal indicators demonstrated that the relative abundances of the genera Anaerotruncus, Angelakisella, Erysipelatoclostridium and Ruminococcaceae_UCG_014 were negatively correlated with the levels of gastrointestinal active peptides. B. bifidum FXJCJ32M2 can increase the relative abundances of Turicibacter and Dubosiella, and this was positively correlated with the expression of aquaporin 8 and vasoactive intestinal peptide receptor 1 but could not effectively alleviate faecal dryness or promote colonic motility. These findings suggest that B. bifidum shows significant intraspecific differences in the remission mechanism and provides a theoretical basis for subsequent population experiments and personalised treatment for constipation.

Promotive effects of sesamin on proliferation and adhesion of intestinal probiotics and its mechanism of action.

The effect of sesamin on intestinal flora was studied by in vitro animal fecal anaerobic fermentation system, and were analyzed by 16S rDNA sequencing. Results showed that sesamin modulated the composition of intestinal microorganisms and reshaped gut microbiome. The abundance of probiotics Lactobacillaceae and Bifidobacteriaceae increased, while the abundance of Enterobacteriaceae decreased. The properties of probiotics (Bifidobacterium bifidum and Lactophilus acidophilus) adhesion to epithelial colon cells (NCM460) were assessed by gram staining and plate counting methods. Results showed that sesamin increased the adhesive index of probiotics. Analysis of RT-qPCR, Western blot and immunofluorescence staining indicated that sesamin up-regulated the expression of the adhesive protein (ß-cadherin and E-cadherin) of NCM460 cells. In conclusion, sesamin could promote the proliferation and adhesion of intestinal probiotics leading to modulating gut microbiota, which provided basis for sesamin as a food-borne functional factor for improving intestinal health.

Bifidobacterium bifidum strains synergize with immune checkpoint inhibitors to reduce tumour burden in mice.

The gut microbiome can influence the development of tumours and the efficacy of cancer therapeutics1-5; however, the multi-omics characteristics of antitumour bacterial strains have not been fully elucidated. In this study, we integrated metagenomics, genomics and transcriptomics of bacteria, and analyses of mouse intestinal transcriptome and serum metabolome data to reveal an additional mechanism by which bacteria determine the efficacy of cancer therapeutics. In gut microbiome analyses of 96 samples from patients with non-small-cell lung cancer, Bifidobacterium bifidum was abundant in patients responsive to therapy. However, when we treated syngeneic mouse tumours with commercial strains of B. bifidum to establish relevance for potential therapeutic uses, only specific B. bifidum strains reduced tumour burden synergistically with PD-1 blockade or oxaliplatin treatment by eliciting an antitumour host immune response. In mice, these strains induced tuning of the immunological background by potentiating the production of interferon-γ, probably through the enhanced biosynthesis of immune-stimulating molecules and metabolites.

Biosynthesis and characterization with antimicrobial activity of TiO2 nanoparticles using probiotic Bifidobacterium bifidum.

Bifidobacterium selectively colonizes the infants' intestinal tract, and the relevant coliform bacteria in adults are particularly beneficial because of their enhanced capability to prevent pathogens of gastro intestine by direct antimicrobial action and relieve infection, which led to their intensification, the antibacterial activities of titanium nanoparticles producing by some bacteria, makes them attractive as a new agent against pathogenic bacteria. In our present study, we used a probiotic bacteria Bifidobacterium bifidum which was isolated from the commercial market capsule to produce TiO2 nanoparticles and study the biologically characterized nanoparticle using various techniques like Scanning Electron Microscopic (SEM), atomic force microscopy (AFM), and study its antimicrobial activity against a bacteria isolated from the stool of patients suffering from acute diarrhea. The results showed that the morphological characteristics of nanoparticles were found to have a spherical shape and mean size of 81 nm by AFM while scanning electron microscope viewed as an oval shape with anatase form synthesized by B. bifidum. TiO2-NP synthesized by B. bifidum had an inhibitory effect against P. aeruginosa, A. baumanii, K. pneumonia at a concentration 16 mg/ml and 32 mg/ml towards E. coli and S. typhi, the minimum inhibitory concentration (MIC) against pathogenic bacteria isolated from acute diarrhea included Pseudomonas aeruginosa, Acinetobacter baumanii, Klebsiella pneumonia, E.coli and salmonella typhi was utilized to determine the antibacterial impact of the synthesized TIO2 nanoparticles. Our biologically synthesized titanium nanoparticles were effective against all the tested pathogenic bacteria at various degrees and had a probable role in significantly greater antimicrobial efficacy against all isolates under study. This trial may have considerable significance for the prevention of antibiotic resistance associated diarrhea in hospitals.

Administration of Bifidobacterium bifidum CGMCC 15068 modulates gut microbiota and metabolome in azoxymethane (AOM)/dextran sulphate sodium (DSS)-induced colitis-associated colon cancer (CAC) in mice.

The gut microbiota plays an important role in colorectal cancer (CRC), and the use of probiotics might be a promising intervention method. The aim of our study was to investigate the beneficial effect of Bifidobacterium bifidum CGMCC 15068 on an azoxymethane (AOM)/dextran sulphate sodium (DSS)-induced colitis-associated CRC (CAC) mouse model. CAC was induced by an intra-peritoneal injection of AOM (10 mg/kg) and three 7-day cycles of 2% DSS in drinking water with a 14-day recovery period between two consecutive DSS administrations. B. bifidum CGMCC 15068 (3 × 109 CFU/mL) was gavaged once daily during the recovery period. Then, the faecal microbial composition and metabolome were profiled using the 16S rRNA sequencing technology and gas chromatography-mass spectrometry (GC-MS), respectively. The administration of B. bifidum CGMCC 15068 attenuated tumourigenesis in the CAC mouse model. In addition, B. bifidum CGMCC 15068 pre-treatment increased the relative abundance of Akkermansia, Desulfovibrionaceae, Romboutsia, Turicibacter, Verrucomicrobiaceae, Ruminococcaceae_UCG_013, Lachnospiraceae_UCG_004, and Lactobacillus. Meanwhile, B. bifidum CGMCC 15068 altered metabolites involved in the citrate cycle (TCA cycle), glycolysis, butyrate metabolism, fatty acid biosynthesis, and galactose metabolism. Several significant correlations were identified between the differentially abundant microbes and metabolites. These findings supported the beneficial role of B. bifidum CGMCC 15068 in intestinal health by modulating dysbiosis and the gut metabolic profile. The manipulation of the gut microbial composition using probiotics might be a promising prevention strategy for CRC. Long-term and large-scale clinical trials are warranted for the potential clinical applications of this strategy in the future.

Heat-inactivated Bifidobacterium bifidum MIMBb75 (SYN-HI-001) in the treatment of irritable bowel syndrome: a multicentre, randomised, double-blind, placebo-controlled clinical trial.

BACKGROUND: Bifidobacterium bifidum MIMBb75 is one of a few probiotic strains that have been shown to be effective in the treatment of irritable bowel syndrome (IBS) and its symptoms. Non-viable strains might have advantages over viable bacteria for product stability and standardisation, as well as for tolerability because safety concerns have been raised for specific patient groups who are susceptible to infection. We aimed to assess the efficacy of non-viable, heat-inactivated (HI) B bifidum MIMBb75 (SYN-HI-001) in the treatment of IBS and its symptoms. METHODS: We did a double-blind, placebo-controlled trial in which patients with IBS were recruited from 20 study sites in Germany and randomly assigned to receive either two placebo capsules or two capsules with a combined total of 1 × 109 non-viable B bifidum HI-MIMBb75 cells to be taken orally once a day for 8 weeks. Eligible patients were diagnosed with IBS according to Rome III criteria and had abdominal pain (≥4 on an 11-point numerical rating scale) on at least 2 days during a 2-week run-in phase. Patients with chronic inflammatory bowel diseases, systemic diseases, cancer, autoimmune diseases, with an intake of antipsychotic medications 3 months before study start, or with an intake of systemic corticosteroids within 1 month before study start were excluded. Randomisation was in a 1:1 ratio according to a computer-generated blocked list. Patients, investigators, clinical monitors, project managers, and statisticians were masked to the randomisation. The primary composite endpoint was the combination of at least 30% improvement of abdominal pain and adequate relief of overall IBS symptoms being fulfilled in at least 4 of 8 weeks during treatment. Analysis of the primary endpoint included all randomly assigned patients receiving at least one dose of study medication and who had no severe protocol violation. Safety analysis included all patients who had taken at least one dose of the study medication and was based on frequency and severity of adverse events, laboratory evaluation, and global assessment of tolerability. This trial is registered with the ISRCTN registry, ISRCTN14066467, and is completed: the results shown here represent the final analysis. FINDINGS: Patients were screened between April 15, 2016, and Feb 3, 2017, and 443 patients were allocated to the placebo group (n=222) or the B bifidum HI-MIMBb75 group (n=221). The composite primary endpoint was reached by 74 (34%) of 221 patients in the B bifidum HI-MIMBb75 group compared with 43 (19%) of 222 in the placebo group (risk ratio 1·7, 95% CI 1·3-2·4; p=0·0007). No serious adverse events occurred in the B bifidum HI-MIMBb75 group; seven adverse events suspected to be related to the study product were reported in the B bifidum HI-MIMBb75 group as were eight in the placebo group. No deaths were reported in this study. The most common reported adverse event with a suspected relationship to the study product was abdominal pain, which was reported in two (<1%) patients in the B bifidum HI-MIMBb75 group and one (<1%) in the placebo group. Tolerability was rated as very good or good by 200 (91%) patients in the B bifidum HI-MIMBb75 group compared with 191 (86%) in the placebo group. INTERPRETATION: This study shows that B bifidum HI-MIMBb75 substantially alleviates IBS and its symptoms in a real-life setting. These results indicate that specific beneficial bacterial effects are mediated independently of cell viability. FUNDING: Synformulas.

Hepcidin and Erythroferrone Correlate with Hepatic Iron Transporters in Rats Supplemented with Multispecies Probiotics.

The influence of probiotic supplementation on iron metabolism remains poorly investigated. However, a range of studies, especially on Lactobacillus plantarum 299v (Lp229v), have indicated a possible positive impact of probiotics on iron absorption. The aim of the study was to determine the effect of multistrain probiotic supply on iron balance. Thirty Wistar rats were randomized into three groups: placebo (KK group), and multistrain probiotic per os in a daily dose of 2.5 × 109 colony forming units (CFU) (PA group) or 1 × 1010 CFU (PB group). Multistrain probiotic consisted of nine bacterial strains: Bifidobacterium bifidum W23, B. lactis W51, B. lactis W52, Lactobacillus acidophilus W37, L. brevis W63, L. casei W56, L. salivarius W24, Lactococcus lactis W19, and Lc. lactis W58, in equal proportions. After six weeks, blood and organ samples were collected. No differences were found between the three groups in terms of serum concentrations of hepcidin (HEPC), lactoferrin (LTF), homocysteine (HCY), ferritin (Ft), or erythroferrone (ErFe), or in liver content of divalent metal transporter 1 (DMT1), transferrin receptors 1 and 2 (TfR), or ZRT/IRT-like protein 14 (ZIP14) proteins. In the overall sample, positive correlations were noted between the serum concentrations of hepcidin and lactoferrin, and hepcidin and ferritin; serum concentration of hepcidin and DMT1 and TfR1 in the liver; and serum concentration of erythroferrone and TfR2 in the liver. The correlations of serum hepcidin and erythroferrone with liver DMT1 and TfR represent significant mechanisms of Fe homeostasis. Our study has shown that multistrain probiotic supplementation used in the experiment did not disrupt the biochemical and hepatic regulatory processes of Fe balance and did not demonstrate significant influence on selected parameters of Fe metabolism.

Antibiotic Susceptibility Profiles of Lactic Acid Bacteria from the Human Vagina and Genetic Basis of Acquired Resistances.

Lactic acid bacteria can act as reservoirs of antibiotic resistance genes that can be ultimately transferred to pathogens. The present work reports on the minimum inhibitory concentration (MIC) of 16 antibiotics to 25 LAB isolates of five Lactobacillus and one Bifidobacterium species from the human vagina. Acquired resistances were detected to kanamycin, streptomycin, chloramphenicol, gentamicin, and ampicillin. A PCR analysis of lactobacilli failed to identify genetic determinants involved in any of these resistances. Surprisingly, a tet(W) gene was detected by PCR in two Bifidobacterium bifidum strains, although they proved to be tetracycline-susceptible. In agreement with the PCR results, no acquired genes were identified in the genome of any of the Lactobacillus spp. strains sequenced. A genome analysis of B. bifidum VA07-1AN showed an insertion of two guanines in the middle of tet(W) interrupting the open reading frame. By growing the strain in the presence of tetracycline, stable tetracycline-resistant variants were obtained. An amino acid substitution in the ribosomal protein S12 (K43R) was further identified as the most likely cause of VA07-1AN being streptomycin resistance. The results of this work expand our knowledge of the resistance profiles of vaginal LAB and provide evidence for the genetic basis of some acquired resistances.

Lactobacillus rhamnosus GG and Bifidobacterium bifidum TMC3115 Can Affect Development of Hippocampal Neurons Cultured In Vitro in a Strain-Dependent Manner.

This study examined whether Lactobacillus rhamnosus GG (LGG) and Bifidobacterium bifidum TMC3115 (TMC3115) could morphologically or physiologically influence hippocampal neuronal development in vitro. Hippocampal neurons cultured in vitro were exposed to live or heat-inactivated LGG or TMC3115 for either 6 or 24 h. Neuronal morphological changes and drebrin (DRB) and synaptophysin (SYP) protein levels were monitored using immunofluorescence. And the levels of DRB, SYP, and brain-derived neurotrophic factor (BDNF), and cAMP-response element binding protein (CREB) mRNA were detected using RT-PCR. The BDNF, CREB, and phosphorylated-CREB (P-CREB) protein levels were detected by extraction-enzyme-linked immunosorbent assay (ELISA) or Western blot assays. Heat-inactivated LGG and TMC3115 could enhance neuron viability, DRB and SYP protein levels, and BDNF mRNA level were significantly altered after exposure to the tested bacteria with 6 h or 24 h. There were no significant differences in neuronal morphology or DRB, SYP, or CREB mRNA levels among the groups following bacterial exposure. However, following exposure of live TMC3115 for 24 h, the neuronal BDNF and P-CREB protein levels were both significantly up-regulated as detected by western blot assays. These results demonstrated that LGG and TMC3115 could affect neuronal viability, along with hippocampal synaptic and functional development, in a strain-dependent manner, which may also be closely associated with the physiological and culture conditions of each strain. Up-regulated P-CREB may be one of the underlying mechanisms by which the bacteria, especially neurons following exposure of live TMC3115 for 24 h, are able to regulate neuronal BDNF protein production.