The effects of AG1® supplementation on the gut microbiome of healthy adults: a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: This study aimed to examine the effect of a commercially available multi-ingredient powder (AG1Ⓡ) on the gut microbiome and assess the impact of AG1Ⓡ on GI tolerability and other clinical safety markers in healthy men and women. METHODS: Using a double-blind, randomized, two-arm, placebo-controlled, parallel design, we examined a 4-week daily supplementation regimen of AG1Ⓡ vs. placebo (PL). Fifteen men and 15 women provided stool samples for microbiome analysis, questionnaires for digestive quality of life (DQLQ), and completed visual analog scales (VAS) and Bristol stool charts to assess stool consistency and bowel frequency before and after the 4-week intervention. Participant's blood work (CBC, CMP, and lipid panel) was also assessed before and after the 4-week intervention. Alpha diversity was determined by Shannon and Chao1 index scores and evaluated by a two-way ANOVA, beta diversity in taxonomic abundances and functional pathways was visualized using partial least squares-discriminant analyses and statistically evaluated by PERMANOVA. To identify key biomarkers, specific feature differences in taxonomic relative abundance and normalized functional pathway counts were analyzed by linear discriminant analysis (LDA) effect size (LEfSe). Questionnaires, clinical safety markers, and hemodynamics were evaluated by mixed factorial ANOVAs with repeated measures. This study was registered on clinicaltrials.gov (NCT06181214). RESULTS: AG1Ⓡ supplementation enriched two probiotic taxa (Lactobacillus acidophilus and Bifidobacterium bifidum) that likely stem from the probiotics species that exist in the product, as well as L. lactis CH_LC01 and Acetatifactor sp900066565 ASM1486575v1 while reducing Clostridium sp000435835. Regarding community function, AG1Ⓡ showed an enrichment of two functional pathways while diminishing none. Alternatively, the PL enriched six, but diminished five functional pathways. Neither treatment negatively impacted the digestive quality of life via DQLQ, bowel frequency via VAS, or stool consistency via VAS and Bristol. However, there may have been a greater improvement in the DQLQ score (+62.5%, p = 0.058, d = 0.73) after four weeks of AG1Ⓡ supplementation compared to a reduction (-50%) in PL. Furthermore, AG1Ⓡ did not significantly alter clinical safety markers following supplementation providing evidence for its safety profile. CONCLUSIONS: AG1Ⓡ can be consumed safely by healthy adults over four weeks with a potential beneficial impact in their digestive symptom quality of life.

Polyphenols and metabolism: from present knowledge to future challenges.

A diet rich in polyphenols and other types of phytonutrients can reduce the occurrence of chronic diseases. However, a well-established cause-and-effect association has not been clearly demonstrated and several other issues will need to be fully understood before general recommendations will be carried out In the present review, some of the future challenges that the research on phenolic compounds will have to face in the next years are discussed: toxicological aspects of polyphenols and safety risk assessment; synergistic effects between different polyphenols; metabotype-based nutritional advice based on a differential gut microbial metabolism of polyphenols (precision nutrition); combination of polyphenols with other bioactive compounds; innovative formulations to improve the bioavailability of phenolic compounds; and polyphenols in sports nutrition and recovery.Other aspects related to polyphenol research that will have a boost in the next years are: polyphenol and gut microbiota crosstalk, including prebiotic effects and biotransformation of phenolic compounds into bioactive metabolites by gut microorganisms; molecular docking, molecular dynamics simulation, and quantum and molecular mechanics studies on the protein-polyphenol complexes; and polyphenol-based coating films, nanoparticles, and hydrogels to facilitate the delivery of drugs, nucleic acids and proteins.In summary, this article provides some constructive inspirations for advancing in the research of the applications, risk assessment and metabolic effects of dietary polyphenols in humans.

Efficacy of prebiotic, probiotic, and synbiotics in improving growth in children under age five years in Africa: A protocol for a systematic review.

Background: Stunting is among the main obstacles to human development affecting millions of children worldwide, particularly in the sub-Saharan Africa region. Randomized clinical trials have shown the positive effects of prebiotics, probiotics, and synbiotics in improving growth in children and toddlers. However, although the global mobilization to tackle its challenges in their different aspects is visible, it remains to define effective large-scale up interventions and strategies to obtain long-lasting impacts. Objective: The objective of this review is to re-evaluate the efficacy of prebiotics, probiotics, and/or synbiotics on growth in children 0 to 5 years in Africa including recently published studies. Methods: Systematic search will be carried out in Pubmed, Science Direct, clinicaltrial.org, and Google Scholar. Both randomized and observational studies that assess the association between prebiotics, probiotics, and synbiotics, and health benefits and growth in children under 5 years of age will be included in the review. PRISMA-P (preferred reporting items for systematic review and meta-analysis protocols) will be used used for this protocol, and PRISMA will be used for the systematic review. The Cochrane Risk Assessment Tool will be used to assess the quality of eligible studies. If the compiled data are appropriate and sufficient enough, we will perform a meta-analysis using RevMan software. Conclusion: This review will provide up-to-date and reliable information on the efficacy of prebiotics, probiotics, and synbiotics on the growth of children under 5 years of age especially in developing countries. PROSPERO registration number CRD42022343138.

Microbes as medicine.

Over the last two decades, advancements in sequencing technologies have significantly deepened our understanding of the human microbiome's complexity, leading to increased concerns about the detrimental effects of antibiotics on these intricate microbial ecosystems. Concurrently, the rise in antimicrobial resistance has intensified the focus on how beneficial microbes can be harnessed to treat diseases and improve health and offer potentially promising alternatives to traditional antibiotic treatments. Here, we provide a comprehensive overview of both established and emerging microbe-centric therapies, from probiotics to advanced microbial ecosystem therapeutics, examine the sophisticated ways in which microbes are used medicinally, and consider their impacts on microbiome homeostasis and health outcomes through a microbial ecology lens. In addition, we explore the concept of rewilding the human microbiome by reintroducing "missing microbes" from nonindustrialized societies and personalizing microbiome modulation to fit individual microbial profiles-highlighting several promising directions for future research. Ultimately, the advancements in sequencing technologies combined with innovative microbial therapies and personalized approaches herald a new era in medicine poised to address antibiotic resistance and improve health outcomes through targeted microbiome management.

Targeting the gut microbiota: a new strategy for colorectal cancer treatment.

BACKGROUND: How to reduce the high incidence rate and mortality of colorectal cancer (CRC) effectively is the focus of current research. Endoscopic treatment of early-stage CRC and colorectal adenomas (CAC) has a high success rate, but although several treatments are available for advanced CRC, such as surgery, radiotherapy, chemotherapy, and immunotherapy, the 5-year survival rate remains low. In view of the high incidence rate and mortality of CRC, early rational drug prevention for high-risk groups and exploration of alternative treatment modalities are particularly warranted. Gut microbiota is the target of and interacts with probiotics, prebiotics, aspirin, metformin, and various Chinese herbal medicines (CHMs) for the prevention of CRC. In addition, the anti-cancer mechanisms of probiotics differ widely among bacterial strains, and both bacterial strains and their derivatives and metabolites have been found to have anti-cancer effects. Gut microbiota plays a significant role in early drug prevention of CRC and treatment of CRC in its middle and late stages, targeting gut microbiota may be a new strategy for colorectal cancer treatment.

Does the Composition of Gut Microbiota Affect Chronic Kidney Disease? Molecular Mechanisms Contributed to Decreasing Glomerular Filtration Rate.

Chronic kidney disease (CKD) is a very prevalent and insidious disease, particularly with initially poorly manifested symptoms that progressively culminate in the manifestation of an advanced stage of the condition. The gradual impairment of kidney function, particularly decreased filtration capacity, results in the retention of uremic toxins and affects numerous molecular mechanisms within the body. The dysbiotic intestinal microbiome plays a crucial role in the accumulation of protein-bound uremic toxins such as p-cresol (pC), indoxyl sulfate (IS), and p-cresyl sulfate (p-CS) through the ongoing fermentation process. The described phenomenon leads to an elevated level of oxidative stress and inflammation, subsequently resulting in tissue damage and complications, particularly an increase in cardiovascular risk, representing the predominant cause of mortality in chronic kidney disease (CKD). Therefore, exploring methods to reduce uremic toxins is currently a pivotal therapeutic strategy aimed at reducing the risk of organ damage in patients with chronic kidney disease (CKD). This review aims to summarize recent discoveries on modifying the composition of the intestinal microbiota through the introduction of special probiotic and synbiotic supplements for CKD therapy. The potential to connect the gut microbiota with CKD opens the possibility for further extensive research in this area, which could lead to the incorporation of synbiotics and probiotics into the fundamental treatment and prevention of CKD.

Effect of In Vitro Digestion on Bioactive Peptides Related to Immune and Gut Health in Intact Cow's Milk and Hydrolyzed Protein-Based Infant Formulas.

Background/Objectives: Human milk is the optimal source of nutrition and protection against infection for infants. If breastfeeding is not possible, standard and hydrolyzed infant formulas (IF) are an alternative. Extensively hydrolyzed IFs (eHFs) contain bioactive peptides, but their activities have rarely been evaluated. The aim of this study was to characterize and compare the bioactive peptide profiles of different eHFs and standard IFs before and after in vitro digestion. Methods: Two forms, liquid and powder, of intact protein formula (iPF) and eHF were subjected to in vitro gastrointestinal digestion, mimicking a young infant's gut (age 0-4 months) and an older infant's gut (>6 months). Bioactive peptides of in vitro digested and undigested formulas were analysed with Liquid Chromatography-Mass Spectrometry (LC-MS). Results: In all samples, a variety of peptides with potential bioactive properties were found. Immuno-regulatory peptides, followed by antimicrobial and antioxidative peptides were most frequent, as were peptides promoting wound healing, increasing mucin secretion, regulating cholesterol metabolism, and preventing bacterial infection. Peptides typically found in yoghurt and colostrum were identified in some formula samples. Conclusions: The high amounts of bioactive peptides with various properties in eHFs and iPFs indicate a possible contribution to infection protection, healthy gut microbiomes, and immunological development of infants. eHFs showed similar compositions of bioactive peptides to iPFs, with intermittently increased peptide variety and quantity.

Effectiveness of Prebiotics and Mediterranean and Plant-Based Diet on Gut Microbiota and Glycemic Control in Patients with Prediabetes or Type 2 Diabetes: A Systematic Review and Meta-Analysis.

BACKGROUND: A high-calorie diet results in the development of prediabetes (PD) or type 2 diabetes mellitus (T2DM). This diet has been reported to cause changes in microbial composition, concentration levels of glycemic parameters, and immune cells or inflammatory cytokines. This systematic review and meta-analysis aimed to evaluate the effects of prebiotics, as well as Mediterranean and plant-based dietary interventions, on gut microbiota composition and glucose homeostasis in individuals with PD or T2D. METHODS: This systematic review and meta-analysis was developed according to the 2020 PRISMA guidelines and checklist. PubMed, EBSCOhost and Google Scholar were the three databases that were used to search for electronically published studies. Data extraction was conducted and examined by the reviewers and all the eligible studies were selected. To test for the quality and biases of the included studies, the Downs and Black checklist was used, followed by the use of Review Manager 5.4. A forest plot was used for meta-analysis and sensitivity analysis. The strength of the evidence was assessed using the Grading of Recommendation Assessment, Development and Evaluation approach. RESULTS: Overall, eight studies met the inclusion criteria: seven focused on patients with T2D, and one focused on patients with PD. The prebiotic dietary intervention did not have a statistically significant effect on glycemic control, including fasting blood glucose (FBG) and glycated hemoglobin (HbA1c). However, one study investigating the Mediterranean diet reported a significant effect on glycemic control. Both prebiotic and Mediterranean dietary interventions were found to beneficially influence gut microbial composition in the intervention groups compared to the placebo groups. No studies assessed the impact of a plant-based diet on microbial composition and glucose parameters. CONCLUSIONS: This review indicated that dietary intervention with a prebiotic or Mediterranean diet shows to beneficially improve the gut microbiota composition of Firmicutes, Bacteroidetes and Bifidobacteria in patients with PD or T2D. However, their beneficial effects on FBG and HbA1c were less clear and uncertain due to limited reports, particularly regarding the Mediterranean dietary intervention.

Effect of Personalized Prebiotic and Probiotic Supplements on the Symptoms of Irritable Bowel Syndrome: An Open-Label, Single-Arm, Multicenter Clinical Trial.

BACKGROUND/OBJECTIVES: Prebiotics and probiotics have been reported to improve symptoms of irritable bowel syndrome (IBS). Nevertheless, the effects of prebiotics/probiotics can vary depending on the IBS subtypes. The purpose of this study was to investigate the effects of personalized prebiotic and probiotic supplements based on intestinal microbiota and IBS subtypes in patients. METHODS: Patients with diarrhea-type IBS (IBS-D), constipation-type IBS (IBS-C), and mixed-type IBS (IBS-M) were enrolled (n = 40 per group; total: n = 120). Personalized prebiotic and probiotic supplements were determined according to the IBS subtypes and intestinal microbiota. The patients received supplements for 4 weeks. The primary outcome was the change in the IBS-severity scoring system from baseline to week 4. RESULTS: The IBS-severity scoring system significantly decreased in all patients (-38.0 [95% confidence interval (CI): -53.6, -22.4]; p < 0.001), in patients with IBS-D (-44.5 [95% CI: -70.6, -18.5]; p = 0.004) and IBS-C (-51.2 [95% CI: -79.4, -22.9]; p = 0.002), but not in those with IBS-M (-20.0 [95% CI: -48.0, 8.1]; p = 0.47). In this study, no serious adverse events were observed that had a causal relationship with the intervention. CONCLUSIONS: In conclusion, personalized prebiotic and probiotic supplements selected according to individual intestinal microbiota and IBS subtype may alleviate the severity of IBS symptoms, particularly in patients with IBS-C and IBS-D.

Comparative Study of Prebiotics for Infants Using a Fecal Culture System: Insights into Responders and Non-Responders.

BACKGROUND: The gut microbiota of breast-fed infants is dominated by infant-type human-residential bifidobacteria (HRB) that contribute to infant health; thus, it is crucial to develop infant formulas that promote the establishment of a gut microbiota enriched with infant-type HRB, closely resembling that of breastfed infants. METHODS: We compared various non-digestible prebiotic oligosaccharides and their combinations using a fecal culture system to explore which candidates could promote the growth of all infant-type HRB and rarely yield non-responders. The analysis included lactulose (LAC), raffinose (RAF), galactooligosaccharides (GOS), and short- and long-chain fructooligosaccharides. Fecal samples were collected from seven infants aged 1.5-10.2 months and cultured with each oligosaccharide individually or their combinations. RESULTS: No single oligosaccharide effectively promoted the growth of all infant-type HRB, although GOS promoted the growth of HRB other than Bifidobacterium longum subsp. longum. Only the LAC/RAF/GOS group evenly and effectively promoted the growth of all infant-type HRB. Accordingly, acetate production was higher in fecal cultures supplemented with GOS or LAC/RAF/GOS than in the other cultures, suggesting that it is a superior combination for all infant-type HRB and rarely yields non-responders. CONCLUSIONS: This study can aid in developing infant formulas that help align the gut microbiota of formula-fed infants with that of breastfed infants.

Gut Microbiome in Alzheimer's Disease: from Mice to Humans.

Alzheimer's disease (AD) is the most prevalent type of dementia, but its etiopathogenesis is not yet fully understood. Recent preclinical studies and clinical evidence indicate that changes in the gut microbiome could potentially play a role in the accumulation of amyloid beta. However, the relationship between gut dysbiosis and AD is still elusive. In this review, the potential impact of the gut microbiome on AD development and progression is discussed. Pre-clinical and clinical literature exploring changes in gut microbiome composition is assessed, which can contribute to AD pathology including increased amyloid beta deposition and cognitive impairment. The gut-brain axis and the potential involvement of metabolites produced by the gut microbiome in AD are also highlighted. Furthermore, the potential of antibiotics, prebiotics, probiotics, fecal microbiota transplantation, and dietary interventions as complementary therapies for the management of AD is summarized. This review provides valuable insights into potential therapeutic strategies to modulate the gut microbiome in AD.

Edodes Cultured Extract Regulates Immune Stress During Puberty and Modulates MicroRNAs Involved in Mammary Gland Development and Breast Cancer Suppression.

BACKGROUND: Immune stressors, such as lipopolysaccharides (LPS), profoundly affect microbiota balance, leading to gut dysbiosis. This imbalance disrupts the metabolic phenotype and structural integrity of the gut, increasing intestinal permeability. During puberty, a critical surge in estrogen levels is crucial for mammary gland development. However, inflammation originating from the gut in this period may interfere with this development, potentially heightening breast cancer risk later. The long-term effects of pubertal inflammation on mammary development and breast cancer risk are underexplored. Such episodes can dysregulate cytokine levels and microRNA expression, altering mammary cell gene expression, and predisposing them to tumorigenesis. METHODS: This study hypothesizes that prebiotics, specifically Lentinula edodes Cultured Extract (AHCC), can counteract LPS's adverse effects. Using BALB/c mice, an acute LPS dose was administered at puberty, and breast cancer predisposition was assessed at 13 weeks. Cytokine and tumor-related microRNA levels, tumor development, and cancer stem cells were explored through immunoassays and qRT-PCR. RESULTS: Results show that LPS induces lasting effects on cytokine and microRNA expression in mammary glands and tumors. AHCC modulates cytokine expression, including IL-1ß, IL-17A/F, and IL-23, and mitigates LPS-induced IL-6 in mammary glands. It also regulates microRNA expression linked to tumor progression and suppression, particularly counteracting the upregulation of oncogenic miR-21, miR-92, and miR-155. Although AHCC slightly alters some tumor-suppressive microRNAs, these changes are modest, highlighting a complex regulatory role that warrants further study. CONCLUSION: These findings underscore the potential of dietary interventions like AHCC to mitigate pubertal LPS-induced inflammation on mammary gland development and tumor formation, suggesting a preventive strategy against breast cancer.

Alterations in the gut microbiota in patients with long-term follow-up after pancreaticoduodenectomy and their association with postoperative fatty liver: A pilot study.

BACKGROUND/PURPOSE: Gut microbiota status after pancreaticoduodenectomy (PD) is unclear, and postoperative fatty liver is an important complication after PD. This study evaluated the relationship between postoperative fatty liver and gut microbiota after PD. METHODS: Fecal samples were collected from patients who had undergone PD and remained stable after 6 months of follow-up. A comprehensive bacterial analysis using 16S rRNA gene amplicon sequencing was performed. The results were compared with those of 85 healthy volunteers. The association between perioperative factors, gut microbiota, and development of fatty liver was investigated. RESULTS: Twenty-four patients after PD, including 10 in the fatty liver (FL) group and 14 in the normal liver (NL) group were investigated. The ß-diversity of the gut microbiota was significantly different between the healthy volunteers and patients after PD, with more Escherichia coli and Streptococcus gallolyticus and less Bifidobacterium catenulatum and Faecalibacterium prausnitzii in the patients with PD. Lactobacillus gasseri was significantly less abundant in the FL group than in the healthy volunteers, although this change was not observed in the NL group. CONCLUSIONS: The gut microbiota of patients after PD was in dysbiosis at postoperative ≥6 months. Development of fatty liver might be associated with significant differences in gut microbiota.

Probiotics, prebiotics, synbiotics and other microbiome-based innovative therapeutics to mitigate obesity and enhance longevity via the gut-brain axis.

The global prevalence of obesity currently exceeds 1 billion people and is accompanied by an increase in the aging population. Obesity and aging share many hallmarks and are leading risk factors for cardiometabolic disease and premature death. Current anti-obesity and pro-longevity pharmacotherapies are limited by side effects, warranting the development of novel therapies. The gut microbiota plays a major role in human health and disease, with a dysbiotic composition evident in obese and aged individuals. The bidirectional communication system between the gut and the central nervous system, known as the gut-brain axis, may link obesity to unhealthy aging. Modulating the gut with microbiome-targeted therapies, such as biotics, is a novel strategy to treat and/or manage obesity and promote longevity. Biotics represent material derived from living or once-living organisms, many of which have therapeutic effects. Pre-, pro-, syn- and post-biotics may beneficially modulate gut microbial composition and function to improve obesity and the aging process. However, the investigation of biotics as next-generation therapeutics has only just begun. Further research is needed to identify therapeutic biotics and understand their mechanisms of action. Investigating the function of the gut-brain axis in obesity and aging may lead to novel therapeutic strategies for obese, aged and comorbid (e.g., sarcopenic obese) patient populations. This review discusses the interrelationship between obesity and aging, with a particular emphasis on the gut microbiome, and presents biotics as novel therapeutic agents for obesity, aging and related disease states.

Causal Relationship Between Gut Microbiota and Leukemia: Future Perspectives.

The gut microbiota plays a crucial role in maintaining homeostasis in the human gastrointestinal tract. Numerous studies have shown a strong association between the gut microbiota and the emergence and progression of various diseases. Leukemia is one of the most common hematologic malignancies. Although standardized protocols and expert consensus have been developed for routine diagnosis and treatment, limitations remain due to individual differences. Nevertheless, a large number of studies have established a link between the gut microbiota and leukemia, with disturbances in the gut microbiota directly or indirectly affecting the development of leukemia. However, the causal relationship between the two remains unclear, and studying and exploring the causal relationship may open up entirely new avenues and protocols for use in the prevention and/or treatment of leukemia, offering new insights into diagnosis and treatment. In this review, the intricate relationship between the gut microbiota and leukemia is explored in depth, including causal associations, metabolite effects, therapeutic applications, and complications. Based on the characteristics of the gut microbiota, the future applications and prospects of gut microbiota are discussed to provide useful information for clinical treatment of leukemia.

The Effects of 1-Kestose on the Abundance of Inflammation-Related Gene mRNA in Adipose Tissue and the Gut Microbiota Composition in Rats Fed a High-Fat Diet.

Chronic inflammation in adipose tissue is thought to contribute to insulin resistance, which involves the gut microbiota. Our previous studies have demonstrated that ingestion of 1-kestose can alter the gut microbiota composition, increase cecal butyrate levels, and improve insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Additionally, we found that 1-kestose supplementation ameliorated insulin resistance in obese rat models fed a high-fat diet (HFD), although the effects of 1-kestose on the abundance of inflammation-related gene in adipose tissue and gut microbiota composition in these rats were not explored. This study aimed to investigate the impact of 1-kestose on these parameters in HFD-fed rats, compared to OLETF rats. Male Sprague-Dawley rats were divided into two dietary groups, control or HFD, for 19 wk. Each group was further subdivided to receive either tap water or tap water supplemented with 2% (w/v) 1-kestose throughout the study. We evaluated gene expression in adipose tissue, as well as short-chain fatty acids (SCFAs) levels and microbial composition in the cecum contents. 1-Kestose intake restored the increased relative abundance of tumor necrosis factor (Tnf) mRNA in adipose tissue and the reduced level of butyrate in the cecum contents of HFD-fed rats to those observed in control diet-fed rats. Additionally, 1-kestose consumption changed the composition of the gut microbiota, increasing Butyricicoccus spp., decreasing UGC-005 and Streptococcus spp., in the cecum contents of HFD-fed rats. Our findings suggest that 1-kestose supplementation reduces adipose tissue inflammation and increases butyrate levels in the gut of HFD-fed rats, associated with changes in the gut microbiota composition, distinct from those seen in OLETF rats.

Valorization of Baltic Sea farmed blue mussels: Chemical profiling and prebiotic potential for nutraceutical and functional food development.

The severe eutrophication of the Baltic Sea requires mussel (Mytilus spp.) farming to remove nutrients, but farming in a low salinity environment results in smaller mussels that require value enhancement to be economically viable. This study evaluates the biomass valorisation of smaller Baltic mussels, focusing on the extraction of oil, protein and glycogen. It analyses the amino acid profiles, oil and fatty acid contents and glycogen levels of the mussels, as well as their prebiotic properties on beneficial gut bacteria. In addition, the study improves the extraction of bioactive compounds through enzymatic hydrolysis. Results indicate significant seasonal differences, with summer mussels having higher meat and lower ash content, and a rich content of essential fatty acids, particularly omega-3, and amino acids, underscoring the mussels' sustainability as a food source. The enzymatically treated biomass exhibited notable prebiotic activity, proposing health-promoting benefits. The study underscores the valorization of Baltic mussel biomass, highlighting its role in health, nutrition, and environmental sustainability.

Probiotics and Fecal Microbiota Transplantation in Major Depression: Doxa or Episteme?

In the human body, eukaryotic somatic cells and prokaryotic microorganisms live together. In this state, the body can be viewed as a "superorganism." Symbiotic life with commensal microorganisms can be observed in almost every part of the body. Intestinal microbiota plays an important role in health and disease, and in shaping and regulating neuronal functions from the intrauterine period to the end of life. Microbiota-based treatment opportunities are becoming more evident in both understanding the etiopathogenesis and treatment of neuropsychiatric disorders, especially depression. Antidepressant drugs, which are the first choice in the treatment of depression, also have antimicrobial and immunomodulatory mechanisms of action. From these perspectives, direct probiotics and fecal microbiota transplantation are treatment options to modulate microbiota composition. There are few preclinical and clinical studies on the effectiveness and safety of these applications in depression. The information obtained from these studies may still be at a doxa level. However, the probability that this information will become episteme in the future seems to be increasing.

In vitro and ex vivo metabolism of chemically diverse fructans by bovine rumen Bifidobacterium and Lactobacillus species.

BACKGROUND: Inulin and inulin-derived fructooligosaccharides (FOS) are well-known prebiotics for use in companion animals and livestock. The mechanisms by which FOS contribute to health has not been fully established. Further, the fine chemistry of fructan structures from diverse sources, such as graminan-type fructans found in cereal crops, has not been fully elucidated. New methods to study fructan structure and microbial responses to these complex carbohydrates will be key for evaluating the prebiotic potency of cereal fructans found in cattle feeds. As the rumen microbiome composition is closely associated with their metabolic traits, such as feed utilization and waste production, prebiotics and probiotics represent promising additives to shift the microbial community toward a more productive state. RESULTS: Within this study, inulin, levan, and graminan-type fructans from winter wheat, spring wheat, and barley were used to assess the capacity of rumen-derived Bifidobacterium boum, Bifidobacterium merycicum, and Lactobacillus vitulinus to metabolize diverse fructans. Graminan-type fructans were purified and structurally characterized from the stems and kernels of each plant. All three bacterial species grew on FOS, inulin, and cereal crop fructans in pure cultures. L. vitulinus was the only species that could metabolize levan, albeit its growth was delayed. Fluorescently labelled polysaccharides (FLAPS) were used to demonstrate interactions with Gram-positive bacteria and confirm fructan metabolism at the single-cell level; these results were in agreement with the individual growth profiles of each species. The prebiotic potential of inulin was further investigated within naïve rumen microbial communities, where increased relative abundance of Bifidobacterium and Lactobacillus species occurred in a dose-dependent and temporal-related manner. This was supported by in situ analysis of rumen microbiota from cattle fed inulin. FLAPS probe derived from inulin and fluorescent in situ hybridization using taxon-specific probes confirmed that inulin interacts with Bifidobacteria and Lactobacilli at the single-cell level. CONCLUSION: This research revealed that rumen-derived Bifidobacteria and Lactobacilli vary in their metabolism of structurally diverse fructans, and that inulin has limited prebiotic potential in the rumen. This knowledge establishes new methods for evaluating the prebiotic potential of fructans from diverse plant sources as prebiotic candidates for use in ruminants and other animals.