Action and function of Faecalibacterium prausnitzii in health and disease

RG-I pectic polysaccharides and hesperidin synergistically modulate gut microbiota: An in vitro study targeting the proportional relationship

In this study, we investigated how different proportions blends of Rhamnogalacturonan-I pectic polysaccharides and hesperidin impact the gut microbiota and metabolites using an in vitro simulated digestion and fermentation model. The results indicated that both of them could modulate the gut microbiota and produce beneficial metabolites. However, their blends in particular proportions (such as 1:1) exhibited remarkable synergistic effects on modulating the intestinal microenvironment, surpassing the effects observed with individual components. Specifically, these blends could benefit the host by increasing short-chain fatty acids production (such as acetate), improving hesperidin bioavailability, producing more metabolites (such as hesperetin, phenolic acids), and promoting the growth of beneficial bacteria. This synergistic and additive effect was inseparable from the role of gut microbiota. Certain beneficial bacteria, such as Blautia, Faecalibacterium, and Prevotella, exhibited strong preferences for those blends, thereby contributing to host health through participating in carbohydrate and flavonoid metabolism.

Crosstalk between butyrate oxidation in colonocyte and butyrate-producing bacteria

The composition of gut microbiota, including butyrate-producing bacteria (BPB), is influenced by diet and physiological conditions. As such, given the importance of butyrate as an energetic substrate in colonocytes, it is unclear whether utilization of this substrate by the host would enhance BPB levels, thus defining a host-microbiome mutualistic relationship based on cellular metabolism. Here, it is shown through using a mouse model that lacks short-chain acyl dehydrogenase (SCAD), which is the first enzyme in the beta-oxidation pathway for short-chain fatty acids (SCFAs), that there is a significant diminishment in BPB at the phylum, class, species, and genus level compared to mice that have SCAD. Furthermore, SCAD-deficient mice do not show a prebiotic response from dietary fiber. Thus, oxidation of SCFAs by the host, which includes butyrate, is important in promoting BPB. These data help define the functional importance of diet-microbiome-host interactions toward microbiome composition, as it relates to function.

Pharmacomicrobiomics: Immunosuppressive Drugs and Microbiome Interactions in Transplantation

The human microbiome is associated with human health and disease. Exogenous compounds, including pharmaceutical products, are also known to be affected by the microbiome, and this discovery has led to the field of pharmacomicobiomics. The microbiome can also alter drug pharmacokinetics and pharmacodynamics, possibly resulting in side effects, toxicities, and unanticipated disease response. Microbiome-mediated effects are referred to as drug-microbiome interactions (DMI). Rapid advances in the field of pharmacomicrobiomics have been driven by the availability of efficient bacterial genome sequencing methods and new computational and bioinformatics tools. The success of fecal microbiota transplantation for recurrent Clostridioides difficile has fueled enthusiasm and research in the field. This review focuses on the pharmacomicrobiome in transplantation. Alterations in the microbiome in transplant recipients are well documented, largely because of prophylactic antibiotic use, and the potential for DMI is high. There is evidence that the gut microbiome may alter the pharmacokinetic disposition of tacrolimus and result in microbiome-specific tacrolimus metabolites. The gut microbiome also impacts the enterohepatic recirculation of mycophenolate, resulting in substantial changes in pharmacokinetic disposition and systemic exposure. The mechanisms of these DMI and the specific bacteria or communities of bacteria are under investigation. There are little or no human DMI data for cyclosporine A, corticosteroids, and sirolimus. The available evidence in transplantation is limited and driven by small studies of heterogeneous designs. Larger clinical studies are needed, but the potential for future clinical application of the pharmacomicrobiome in avoiding poor outcomes is high.

Exploring the diagnostic potential of immunoglobulin A-microbiota interplay in liver cirrhosis and spontaneous bacterial peritonitis

The human gut microbiota significantly impacts health, including liver conditions like liver cirrhosis (LC) and spontaneous bacterial peritonitis (SBP). Immunoglobulin A (IgA) plays a central role in maintaining gut microbial balance. Understanding IgA's interplay with gut microbiota and liver health is crucial. This study explores the relationship between fecal IgA levels, gut microbiota, and liver injury severity. A total of 69 LC patients and 30 healthy controls were studied. Fecal IgA levels were measured using ELISA, and IgA-coated bacteria were quantified via flow cytometry. Microbiota diversity and composition were assessed through 16S rRNA sequencing. Liver injury severity was graded using the Child-Pugh score. Statistical analyses determined correlations. LC patients had higher fecal IgA levels than controls, correlating positively with liver injury severity. Microbiota diversity decreased with severity, accompanied by shifts in composition favoring pro-inflammatory species. Ralstonia abundance positively correlated with liver injury, whereas Faecalibacterium showed a negative correlation. Specific microbial markers for SBP were identified. Functional profiling revealed altered microbial functionalities in LC and SBP. Elevated fecal IgA levels, coupled with microbiota alterations, correlate with liver injury severity in LC patients. Modulating gut microbiota could be a promising strategy for managing liver-related conditions. Further research is needed to understand underlying mechanisms and translate findings into clinical practice, potentially improving patient outcomes.

Gut microbiota dysbiosis contributes to α-synuclein-related pathology associated with C/EBPβ/AEP signaling activation in a mouse model of Parkinson's disease

JOURNAL/nrgr/04.03/01300535-202409000-00042/figure1/v/2024-01-16T170235Z/r/image-tiff Parkinson's disease is a neurodegenerative disease characterized by motor and gastrointestinal dysfunction. Gastrointestinal dysfunction can precede the onset of motor symptoms by several years. Gut microbiota dysbiosis is involved in the pathogenesis of Parkinson's disease, whether it plays a causal role in motor dysfunction, and the mechanism underlying this potential effect, remain unknown. CCAAT/enhancer binding protein β/asparagine endopeptidase (C/EBPβ/AEP) signaling, activated by bacterial endotoxin, can promote α-synuclein transcription, thereby contributing to Parkinson's disease pathology. In this study, we aimed to investigate the role of the gut microbiota in C/EBPβ/AEP signaling, α-synuclein-related pathology, and motor symptoms using a rotenone-induced mouse model of Parkinson's disease combined with antibiotic-induced microbiome depletion and fecal microbiota transplantation. We found that rotenone administration resulted in gut microbiota dysbiosis and perturbation of the intestinal barrier, as well as activation of the C/EBP/AEP pathway, α-synuclein aggregation, and tyrosine hydroxylase-positive neuron loss in the substantia nigra in mice with motor deficits. However, treatment with rotenone did not have any of these adverse effects in mice whose gut microbiota was depleted by pretreatment with antibiotics. Importantly, we found that transplanting gut microbiota derived from mice treated with rotenone induced motor deficits, intestinal inflammation, and endotoxemia. Transplantation of fecal microbiota from healthy control mice alleviated rotenone-induced motor deficits, intestinal inflammation, endotoxemia, and intestinal barrier impairment. These results highlight the vital role that gut microbiota dysbiosis plays in inducing motor deficits, C/EBPβ/AEP signaling activation, and α-synuclein-related pathology in a rotenone-induced mouse model of Parkinson's disease. Additionally, our findings suggest that supplementing with healthy microbiota may be a safe and effective treatment that could help ameliorate the progression of motor deficits in patients with Parkinson's disease.

Modulatory role of Faecalibacterium on insulin resistance and coagulation in patients with post-viral long haulers depending on adiposity

Patients with Post-viral long hauler encompass lasting symptoms and comorbid complexities, often exacerbated in individuals with excessive body weight. The aim was to study gut microbiota in 130 patients with post-viral long hauler stratified by body mass index (BMI) and the relationship between inflammation and microbiota. Significant higher values were found for anthropometric variables and markers of glucose and dyslipidemia in individuals with higher BMI, as well as elevated levels of C-reactive protein, fibrinogen, IL-6, uric acid, and D-dimer. An interactive association showed an interplay between Faecalibacterium, D-dimer levels, and insulin resistance. This investigation showed that anthropometric, biochemical, and inflammatory variables were impaired in patients with post-viral long haulers with higher BMI. In addition, gut microbiota differences were found between groups and a modification effect on Faecalibacterium abundance regarding insulin resistance and D-dimer. These findings suggest that considering adiposity and gut microbiota structure and composition may improve personalized clinical interventions in patients with chronic inflammation.

Microplastics promote methane emission in estuarine and coastal wetlands

Increasing microplastic (MP) pollution poses significant threats to estuarine and coastal ecosystems. However, the effects of MPs on the emission of methane (CH4), a potent greenhouse gas, within these ecosystems and the underlying regulatory mechanisms have not been elucidated. Here, a combination of 13C stable isotope-based method and molecular techniques was applied to investigate how conventional petroleum-based MPs [polyethylene (PE) and polyvinyl chloride (PVC)] and biodegradable MPs [polylactic acid (PLA) and polyadipate/butylene terephthalate (PBAT)] regulate CH4 production and consumption and thus affect CH4 emission dynamics in estuarine and coastal wetlands. Results indicated that both conventional and biodegradable MPs enhanced the emission of CH4 (P < 0.05), with the promoting effect being more significant for biodegradable MPs. However, the mechanisms by which conventional and biodegradable MPs promote CH4 emissions were different. Specifically, conventional MPs stimulated the emission of CH4 by inhibiting the processes of CH4 consumption, but had no significant effect on CH4 production rate. Nevertheless, biodegradable MPs promoted CH4 emissions via accelerating the activities the methanogens while inhibiting the oxidation of CH4, thus resulting in a higher degree of promoting effect on CH4 emissions than conventional MPs. Consistently, quantitative PCR further revealed a significant increase in the abundance of methyl-coenzyme M reductase gene (mcrA) of methanogens under the exposure of biodegradable MPs (P < 0.05), but not conventional MPs. Furthermore, the relative abundance of most genes involved in CH4 oxidation exhibited varying degrees of reduction after exposure to all types of MPs, based on metagenomics data. This study reveals the effects of MPs on CH4 emissions in estuarine and coastal ecosystems and their underlying mechanisms, highlighting that the emerging biodegradable MPs exhibited a greater impact than conventional MPs on promoting CH4 emissions in these globally important ecosystems, thereby accelerating global climate change.

A further examination of growth factors, T helper 1 polarization, and the gut microbiome in major depression: Associations with reoccurrence of illness, cognitive functions, suicidal behaviors, and quality of life

Growth factors, T helper (Th)1 polarization, and the microbiome are involved in the pathophysiology of major depression (MDD). It remains unclear whether the combination of these three pathways could enhance the accuracy of predicting the features of MDD, including recurrence of illness (ROI), suicidal behaviors and the phenome. We measured serum stem cell factor (SCF), stem cell growth factor (SCGF), stromal cell-derived factor-1 (SDF-1), platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), macrophage-colony stimulating factor (M-CSF) and vascular endothelial growth factor (VEGF), the ratio of serum Th1/Th2 cytokines (zTh1-zTh2), and the abundances of gut microbiome taxa by analyzing stool samples using 16S rDNA sequencing from 32 MDD patients and 37 healthy controls. The results show that serum SCF is significantly lower and VEGF increased in MDD. Adverse childhood experiences (ACE) and ROI are significantly associated with lowered SCF and increasing VEGF. Lifetime and current suicidal behaviors are strongly predicted (63.5%) by an increased VEGF/SCF ratio, Th1 polarization, a gut microbiome enterotype indicating gut dysbiosis, and lowered abundance of Dorea and Faecalobacterium. Around 80.5% of the variance in the phenome's severity is explained by ROI, ACEs, and lowered Parabacteroides distasonis and Clostridium IV abundances. A large part of the variance in health-related quality of life (54.1%) is explained by the VEGF/SCF ratio, Th1 polarization, ACE, and male sex. In conclusion, key features of MDD are largely predicted by the cumulative effects of ACE, Th1 polarization, aberrations in growth factors and the gut microbiome with increased pathobionts but lowered beneficial symbionts.

Bifidobacterium bifidum alleviates adenine-induced acute kidney injury in mice by improving intestinal barrier function

Acute kidney injury (AKI) is a kind of critical kidney disease characterized by tubular injury, rapid decline of renal function and renal inflammation, with high clinical incidence. AKI has been shown to be associated with dysregulation of the gut microbiota and impaired intestinal barrier. Bifidobacterium has a positive impact on the treatment of many diseases. However, little is known about the role and mechanism of Bifidobacterium in AKI. Based on previous experiments, Bifidobacterium bifidum FL228.1 and FL276.1, which can relieve intestinal inflammation, and Bifidobacterium bifidum ZL.1, which has anti-inflammatory potential, were screened. This study aimed to investigate the effects of Bifidobacterium bifidum FL228.1, FL276.1 and ZL.1 on AKI, focusing on their role in the gut microbiota composition and intestinal barrier function. Our results showed that Bifidobacterium bifidum FL228.1, FL276.1 and ZL.1 effectively improved kidney function in mice with AKI by regulating the gut microbiota dysregulation, inhibiting intestinal inflammation and rebuilding the intestinal mucosal barrier. In addition, intervention with probiotics turned the gut microbiota disturbance caused by AKI into a normalized trend, reversed the adverse outcome of microbiota imbalance, and increased the abundance of potentially beneficial bacteria Bifidobacterium and Faecalibaculum. In summary, Bifidobacterium bifidum FL228.1, FL276.1, and ZL.1 alleviate adenine-induced AKI based on the gut-kidney axis. Although their mechanisms of action are different, their effect on alleviating AKI is almost the same.

Bifidobacterium animalis subsp. lactis LPL-RH improves postoperative gastrointestinal symptoms and nutrition indexes by regulating the gut microbiota in patients with valvular heart disease: a randomized controlled trial

Gastrointestinal symptoms constitute a frequent complication in postoperative patients with valvular heart disease (VHD), impacting their postoperative recovery. Probiotics contribute to regulating human gut microbiota balance and alleviating postoperative gastrointestinal symptoms. Our objective involved assessing the potential of Bifidobacterium animalis subsp. lactis LPL-RH to alleviate postoperative gastrointestinal symptoms and expedite patient recovery. Adult patients diagnosed with VHD scheduled for valve surgery were enrolled. 110 patients were randomly divided into two groups and received LPL-RH or a placebo for 14 days. Gastrointestinal symptoms were evaluated using the Gastrointestinal Symptoms Questionnaire. An analysis of the time to recovery of bowel function and various postoperative variables was conducted in both study groups. Variations in the intestinal microbiota were detected via 16S rRNA sequencing. The study was completed by 105 participants, with 53 in the probiotic group and 52 in the placebo group. Compared to the placebo group, LPL-RH significantly reduced the total gastrointestinal symptom score after surgery (p = 0.004). Additionally, LPL-RH was found to significantly reduce abdominal pain (p = 0.001), bloating (p = 0.018), and constipation (p = 0.022) symptom scores. Furthermore, LPL-RH dramatically shortened the time to recovery of bowel function (p = 0.017). Moreover, LPL-RH administration significantly enhanced patients' postoperative nutrition indexes (red blood cell counts, hemoglobin level, p < 0.05). Microbiome analysis showed that the composition and diversity of the postoperative intestinal microbiota differed between the probiotic and placebo groups. No adverse incidents associated with probiotics were documented, emphasizing their safety. This study initially discovered that oral B. animalis subsp. lactis LPL-RH can assist in regulating intestinal microbiota balance, alleviating gastrointestinal symptoms, promoting intestinal function recovery, and enhancing nutrition indexes in patients with VHD after surgery. Regulating the intestinal microbiota may represent a potential mechanism for LPL-RH to exert clinical benefits.

Gut microbiome-immune interactions and their role in rheumatoid arthritis development

Objective

The primary objective is to study the impact of gut microbiota and their interactions with diverse immunological markers on the development of rheumatoid arthritis.

Methods

This study was performed in Astana, Kazakhstan, and included 77 Kazakh female patients older than 18 years, who met the American College of Rheumatology 2010 classification criteria for rheumatoid arthritis (RA), and 113 healthy controls. The DNA was extracted from fecal samples obtained from all study participants for subsequent sequencing at the 16S rRNA gene V1-V3 locus, facilitating the analysis of the gut microbiome. The Multiplex immunoassay was employed to measure the concentrations of inflammatory cytokines, chemokines, and immunoglobulins in both fecal and plasma samples.

Results

Our taxonomic analysis revealed significant differences in the composition of the gut microbiota between the healthy control cohort and the cohort with rheumatoid arthritis RA. Alpha diversity was significantly lower in the RA group. Lachnospiraceae were the most abundant taxon and found to be crucial, showing correlations with immunological markers such as IL5. Additionally, Lachnospiraceae and Oscillospiraceae exhibited the most predictable power and distinguished the composition of both study groups.

Conclusion

Our study identifies key differences in the gut microbiome of RA patients, revealing distinct microbial patterns and specific taxa abundance. We highlight potential biomarkers in immunological and bacterial pathways, offering insights into RA development and indicating possibilities for personalized treatment.

Age-specific composition of milk microbiota in Tibetan sheep and goats

This study investigates the dynamic changes in milk nutritional composition and microbial communities in Tibetan sheep and goats during the first 56 days of lactation. Milk samples were systematically collected at five time points (D0, D7, D14, D28, D56) post-delivery. In Tibetan sheep, milk fat, protein, and casein contents were highest on D0, gradually decreased, and stabilized after D14, while lactose and galactose levels showed the opposite trend. Goat milk exhibited similar initial peaks, with significant changes particularly between D0, D7, D14, and D56. 16S rRNA gene sequencing revealed increasing microbial diversity in both species over the lactation period. Principal coordinates analysis identified distinct microbial clusters corresponding to early (D0-D7), transitional (D14-D28), and mature (D56) stages. Core phyla, including Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, dominated the milk microbiota, with significant temporal shifts. Core microbes like Lactobacillus, Leuconostoc, and Streptococcus were common in both species, with species-specific taxa observed (e.g., Pediococcus in sheep, Shewanella in goats). Furthermore, we observed a highly shared core microbiota in sheep and goat milk, including Lactobacillus, Leuconostoc, and Streptococcus. Spearman correlation analysis highlighted significant relationships between specific microbial genera and milk nutrients. For instance, Lactobacillus positively correlated with total solids, non-fat milk solids, protein, and casein, while Mannheimia negatively correlated with protein content. This study underscores the complex interplay between milk composition and microbial dynamics in Tibetan sheep and goats, informing strategies for livestock management and nutritional enhancement. KEY POINTS: • The milk can be classified into three types based on the microbiota composition • The changes of milk microbiota are closely related to the variations in nutrition • Filter out microbiota with species specificity and age specificity in the milk.

KL-Biome (Postbiotic Formulation of Lactiplantibacillus plantarum KM2) Improves Dexamethasone-Induced Muscle Atrophy in Mice

Sarcopenia refers to an age-related decrease in muscle mass and strength. The gut-muscle axis has been proposed as a promising target to alleviate muscle atrophy. The effect of KL-Biome-a postbiotic preparation comprising heat-killed Lactiplantibacillus plantarum KM-2, its metabolites, and an excipient (soybean powder)-on muscle atrophy was evaluated using dexamethasone (DEX)-induced atrophic C2C12 myoblasts and C57BL/6J mice. KL-Biome significantly downregulated the expression of genes (Atrogin-1 and MuRF1) associated with skeletal muscle degradation but increased the anabolic phosphorylation of FoxO3a, Akt, and mTOR in C2C12 cells. Oral administration of KL-Biome (900 mg/kg) for 8 weeks significantly improved muscle mass, muscle function, and serum lactate dehydrogenase levels in DEX-treated mice. KL-Biome administration increased gut microbiome diversity and reversed DEX-mediated gut microbiota alterations. Furthermore, it significantly increased the relative abundances of the genera Subdologranulum, Alistipes, and Faecalibacterium prausnitzii, which are substantially involved in short-chain fatty acid production. These findings suggest that KL-Biome exerts beneficial effects on muscle atrophy by regulating gut microbiota.

Non-lactic acid bacteria probiotics isolated from intestine or various circumstances

Probiotics are live microorganisms beneficial to host health, predominantly comprising lactic acid bacteria (LAB) such as Lactobacillus. Additional non-LAB probiotics, termed intestinal isolates, encompass next-generation strains like Akkermansia muciniphila, Faecalibacterium prausnitzii, Christensenella minuta, Anaerobutyricum soehngenii, Oxalobacter formigenes, etc. and alongside externally sourced Bacillus, Saccharomyces cerevisiae, Clostridium butyricum, and Propionibacterium. Intestinal-derived probiotics represent strictly anaerobic strains with challenging culturing requirements, contrasting with the aerobic nature of Bacillus probiotics and the ease of culturing S. cerevisiae. These strains exhibit diverse health-promoting properties, encompassing antimicrobial, anticancer, antioxidant, and vitamin production capabilities, albeit contingent upon strain specificity. This review delineates the characteristics, culturing conditions, and health advantages associated with non-LAB probiotics.

Research trends of next generation probiotics

Gut represents one of the largest interfaces for the interaction of host factors and the environmental ones. Gut microbiota, largely dominated by bacterial community, plays a significant role in the health status of the host. The healthy gut microbiota fulfills several vital functions such as energy metabolism, disease protection, and immune modulation. Dysbiosis, characterized by microbial imbalance, can contribute to the development of various disorders, including intestinal, systemic, metabolic, and neurodegenerative conditions. Probiotics offer the potential to address dysbiosis and improve overall health. Advancements in high-throughput sequencing, bioinformatics, and omics have enabled mechanistic studies for the development of bespoke probiotics, referred to as next generation probiotics. These tailor-made probiotics have the potential to ameliorate specific disease conditions and thus fulfill the specific consumer needs. This review discusses recent updates on the most promising next generation probiotics, along with the challenges that must be addressed to translate this concept into reality.

Vitamin D: An Essential Nutrient in the Dual Relationship between Autoimmune Thyroid Diseases and Celiac Disease-A Comprehensive Review

Autoimmune thyroid diseases (AITD) are among the most frequent autoimmune disorders, with a multifactorial etiology in which both genetic and environmental determinants are probably involved. Celiac disease (CeD) also represents a public concern, given its increasing prevalence due to the recent improvement of screening programs, leading to the detection of silent subtypes. The two conditions may be closely associated due to common risk factors, including genetic setting, changes in the composition and diversity of the gut microbiota, and deficiency of nutrients like vitamin D. This comprehensive review discussed the current evidence on the pivotal role of vitamin D in modulating both gut microbiota dysbiosis and immune system dysfunction, shedding light on the possible relevance of an adequate intake of this nutrient in the primary prevention of AITD and CeD. While future technology-based strategies for proper vitamin D supplementation could be attractive in the context of personalized medicine, several issues remain to be defined, including standardized assays for vitamin D determination, timely recommendations on vitamin D intake for immune system functioning, and longitudinal studies and randomized controlled trials to definitely establish a causal relationship between serum vitamin D levels and the onset of AITD and CeD.

The Influence of a High-Cholesterol Diet and Forced Training on Lipid Metabolism and Intestinal Microbiota in Male Wistar Rats

Adequate experimental animal models play an important role in an objective assessment of the effectiveness of medicines and functional foods enriched with biologically active substances. The aim of our study was a comparative assessment of the effect of consumption of 1 or 2% cholesterol with and without regular (two times a week), moderate running exercise on the main biomarkers of lipid and cholesterol metabolism, as well as the intestinal microbiota of male Wistar rats. In experimental rats, a response of 39 indicators (body weight, food consumption, serum biomarkers, liver composition, and changes in intestinal microbiota) was revealed. Total serum cholesterol level increased 1.8 times in animals consuming cholesterol with a simultaneous increase in low-density lipoprotein cholesterol (2 times) and decrease in high-density lipoprotein cholesterol (1.3 times) levels compared to the control animals. These animals had 1.3 times increased liver weight, almost 5 times increased triglycerides level, and more than 6 times increased cholesterol content. There was a tendency towards a decrease in triglycerides levels against the background of running exercise. The consumption of cholesterol led to a predominance of the Bacteroides family, due to a decrease in F. prausnitzii (1.2 times) and bifidobacteria (1.3 times), as well as an increase in Escherichia family (1.2 times). The running exercise did not lead to the complete normalization of microbiota.

Supplementation with soluble or insoluble rice-bran fibers increases short-chain fatty acid producing bacteria in the gut microbiota in vitro

Introduction

Studies have shown that a diet high in fiber and prebiotics has a positive impact on human health due largely to the fermentation of these compounds by the gut microbiota. One underutilized source of fiber may be rice bran, a waste product of rice processing that is used most frequently as an additive to livestock feed but may be a good source of fibers and other phenolic compounds as a human diet supplement. Previous studies focused on specific compounds extracted from rice bran showed that soluble fibers extracted from rice bran can improve glucose response and reduce weight gain in mouse models. However, less is known about changes in the human gut microbiota in response to regular rice bran consumption.

Methods

In this study, we used a Simulator of the Human Intestinal Microbial Ecology (SHIME®) to cultivate the human gut microbiota of 3 different donors in conditions containing either soluble or insoluble fiber fractions from rice bran. Using 16S rRNA amplicon sequencing and targeted metabolomics via Gas Chromatography-Mass Spectrometry, we explored how gut microbial communities developed provided different supplemental fiber sources.

Results

We found that insoluble and soluble fiber fractions increased short-chain fatty acid production, indicating that both fractions were fermented. However, there were differences in response between donors, for example the gut microbiota from donor 1 increased acetic acid production with both fiber types compared with control; whereas for donors 2 and 3, butanoic acid production increased with ISF and SF supplementation. Both soluble and insoluble rice bran fractions increased the abundance of Bifidobacterium and Lachnospiraceae taxa.

Discussion

Overall, analysis of the effect of soluble and insoluble rice bran fractions on the human in vitro gut microbiota and the metabolites produced revealed individually variant responses to these prebiotics.

The Role of Gut-derived Short-Chain Fatty Acids in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic condition affecting the central nervous system (CNS), where the interplay of genetic and environmental factors influences its pathophysiology, triggering immune responses and instigating inflammation. Contemporary research has been notably dedicated to investigating the contributions of gut microbiota and their metabolites in modulating inflammatory reactions within the CNS. Recent recognition of the gut microbiome and dietary patterns as environmental elements impacting MS development emphasizes the potential influence of small, ubiquitous molecules from microbiota, such as short-chain fatty acids (SCFAs). These molecules may serve as vital molecular signals or metabolic substances regulating host cellular metabolism in the intricate interplay between microbiota and the host. A current emphasis lies on optimizing the health-promoting attributes of colonic bacteria to mitigate urinary tract issues through dietary management. This review aims to spotlight recent investigations on the impact of SCFAs on immune cells pivotal in MS, the involvement of gut microbiota and SCFAs in MS development, and the considerable influence of probiotics on gastrointestinal disruptions in MS. Comprehending the gut-CNS connection holds promise for the development of innovative therapeutic approaches, particularly probiotic-based supplements, for managing MS.

Roles of gut microbiota in androgenetic alopecia: insights from Mendelian randomization analysis

Background

Androgenetic alopecia (AGA) is the most common type of androgen-associated hair loss. Previous studies have indicated an association between the gut microbiota and AGA. To delve deeper, we executed a two-sample Mendelian randomization (MR) analysis to investigate the potential causal relationship between the gut microbiota and AGA.

Methods

A two-sample MR investigation was utilized to delve into the intricate interplay between gut microbiota and AGA. Information regarding 211 gut microbial taxa was sourced from the MiBioGen consortium. The summary statistics of the genome-wide association studies (GWAS) for AGA were obtained from the FinnGen biobank, which included 195 cases and 201,019 controls. Various analytical approaches, including Inverse Variance Weighting (IVW), Weighted Median, MR-Egger, Weighted Mode, and Simple Mode were employed to evaluate the causal impact of gut microbiota on AGA. Sensitivity analyses were subsequently conducted to affirm the robustness of the findings.

Results

A two-sample MR investigation unveiled the genus Olsenella, genus Ruminococcaceae UCG-004, and genus Ruminococcaceae UCG-010 were identified as risk factors associated with AGA. In contrast, the family Acidaminococcaceae and genus Anaerofilum, along with the genus Ruminiclostridium 9, demonstrated a protective effect. The sensitivity analyses provided additional assurance that the findings of the current study were less susceptible to the influence of confounding variables and biases.

Conclusion

The MR study has established a link between specific gut microbiota and AGA, offering evidence for the identification of more precisely targeted probiotics. This discovery has the potential to aid in the prevention, control, and reversal of AGA progression.

Human-gut bacterial protein-protein interactions: understudied but impactful to human health

The human gut microbiome is associated with a wide range of diseases; yet, the mechanisms these microbes use to influence human health are not fully understood. Protein-protein interactions (PPIs) are increasingly identified as a potential mechanism by which gut microbiota influence their human hosts. Similar to some PPIs observed in pathogens, many disease-relevant human-gut bacterial PPIs function by interacting with components of the immune system or the gut barrier. Here, we highlight recent advances in these two areas. It is our opinion that there is a vastly unexplored network of human-gut bacterial PPIs that contribute to the prevention or pathogenesis of various diseases and that future research is warranted to expand PPI discovery.

Prophybiotics for in-ovo stimulation; validation of effects on gut health and production of broiler chickens

Probiotics and phytobiotics have demonstrated effective improvement of gut health in broiler chickens when individually administered in-ovo. However, their combined use in-ovo, has not been studied to date. We coined the term "prophybiotic" (probiotic + phytobiotic) for such a combination. The current study therefore, aimed to elucidate the effects of combined use of a selected probiotic and a phytobiotic in-ovo, on broiler gut health and production parameters, as opposed to use of probiotics alone. ROSS 308 hatching eggs were injected with either Leuconostoc mesenteroides (probiotic: PB) or L. mesenteroides with garlic aqueous extract (prophyiotic: PPB) on the 12th day of incubation. Relative abundances of bacteria in feces and cecal content (qPCR), immune related gene expression in cecal mucosa (qPCR) and histomorphology of cecal tissue (PAS staining) were analyzed along with production parameters (hatch quality, body weight, feed efficiency and slaughter and meat quality). PPB treatment increased the abundance of faecalibacteria and bifidobacteria in feces (d 7) and Akkermansia sp. in cecal content. Moreover, it decreased Escherichia coli abundance in both feces (d 34) and cecal content. PB treatment only increased the faecalibacteria in feces (d 7) and Akkermansia sp. in the cecal content. Moreover, PPB treatment resulted in up-regulation of immune related genes (Avian beta defensing 1, Free fatty acid receptor 2 and Mucin 6) and increased the crypt depth in ceca whereas PB treatment demonstrated a higher crypt depth and a tendency to increase Mucin 6 gene expression. Both treatments did not impair the production parameters studied. In conclusion, our results suggest that in-ovo PPB treatment may have enhanced potential in boosting the immune system without compromising broiler production and efficiency, as compared to the use of probiotic alone. Our study, highlights the potential of carefully selected PPB combinations for better results in improving gut health of broiler chickens.

Gut microbiota and metabolic biomarkers in metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), a replacement of the nomenclature employed for NAFLD, is the most prevalent chronic liver disease worldwide. Despite its high global prevalence, NAFLD is often under-recognized due to the absence of reliable noninvasive biomarkers for diagnosis and staging. Growing evidence suggests that the gut microbiome plays a significant role in the occurrence and progression of NAFLD by causing immune dysregulation and metabolic alterations due to gut dysbiosis. The rapid advancement of sequencing tools and metabolomics has enabled the identification of alterations in microbiome signatures and gut microbiota-derived metabolite profiles in numerous clinical studies related to NAFLD. Overall, these studies have shown a decrease in α-diversity and changes in gut microbiota abundance, characterized by increased levels of Escherichia and Prevotella, and decreased levels of Akkermansia muciniphila and Faecalibacterium in patients with NAFLD. Furthermore, bile acids, short-chain fatty acids, trimethylamine N-oxide, and tryptophan metabolites are believed to be closely associated with the onset and progression of NAFLD. In this review, we provide novel insights into the vital role of gut microbiome in the pathogenesis of NAFLD. Specifically, we summarize the major classes of gut microbiota and metabolic biomarkers in NAFLD, thereby highlighting the links between specific bacterial species and certain gut microbiota-derived metabolites in patients with NAFLD.

Dynamic changes in the gut microbiota after bismuth quadruple therapy and high-dose dual therapy for Helicobacter pylori eradication

BACKGROUND

A novel regimen with high-dose dual therapy (HDDT) has emerged, but its impact on the gut microbiota is not well understood. This study aimed to evaluate the impact of HDDT on the gut microbiota and compare it with that of bismuth quadruple therapy (BQT).

METHODS

We enrolled outpatients (18-70 years) diagnosed with Helicobacter pylori infection by either histology or a positive 13C-urea breath test (13C-UBT) and randomly assigned to either the BQT or HDDT group. Subjects consented to provide fecal samples which were collected at baseline, Week 2, and Week 14. Amplification of the V1 and V9 regions of the 16S rRNA was conducted followed by high-throughput sequencing.

RESULTS

Ultimately, 78 patients (41 patients in the HDDT group and 37 in the BQT group) were enrolled in this study. Eradication therapy significantly altered the diversity of the gut microbiota. However, the alpha diversity rebounded only in the HDDT group at 12 weeks post-eradication. Immediately following eradication, the predominance of Proteobacteria, replacing commensal Firmicutes and Bacteroidetes, did not recover after 12 weeks. Species-level analysis showed that the relative abundances of Klebsiella pneumoniae and Escherichia fergusonii significantly increased in both groups at Week 2. Enterococcus faecium and Enterococcus faecalis significantly increased in the BQT group, with no significant difference observed in the HDDT group. After 12 weeks of treatment, the relative abundance of more species in the HDDT group returned to baseline levels.

CONCLUSION

Eradication of H. pylori can lead to an imbalance in gut microbiota. Compared to BQT, the HDDT is a regimen with milder impact on gut microbiota.

Local and Systemic Effects of Bioactive Food Ingredients: Is There a Role for Functional Foods to Prime the Gut for Resilience?

Scientific advancements in understanding the impact of bioactive components in foods on the gut microbiota and wider physiology create opportunities for designing targeted functional foods. The selection of bioactive ingredients with potential local or systemic effects holds promise for influencing overall well-being. An abundance of studies demonstrate that gut microbiota show compositional changes that correlate age and disease. However, navigating this field, especially for non-experts, remains challenging, given the abundance of bioactive ingredients with varying levels of scientific substantiation. This narrative review addresses the current knowledge on the potential impact of the gut microbiota on host health, emphasizing gut microbiota resilience. It explores evidence related to the extensive gut health benefits of popular dietary components and bioactive ingredients, such as phytochemicals, fermented greens, fibres, prebiotics, probiotics, and postbiotics. Importantly, this review distinguishes between the potential local and systemic effects of both popular and emerging ingredients. Additionally, it highlights how dietary hormesis promotes gut microbiota resilience, fostering better adaptation to stress-a hallmark of health. By integrating examples of bioactives, this review provides insights to guide the design of evidence-based functional foods aimed at priming the gut for resilience.

Strain-Specific Anti-Inflammatory Effects of Faecalibacterium prausnitzii Strain KBL1027 in Koreans

Faecalibacterium prausnitzii is one of the most dominant commensal bacteria in the human gut, and certain anti-inflammatory functions have been attributed to a single microbial anti-inflammatory molecule (MAM). Simultaneously, substantial diversity among F. prausnitzii strains is acknowledged, emphasizing the need for strain-level functional studies aimed at developing innovative probiotics. Here, two distinct F. prausnitzii strains, KBL1026 and KBL1027, were isolated from Korean donors, exhibiting notable differences in the relative abundance of F. prausnitzii. Both strains were identified as the core Faecalibacterium amplicon sequence variant (ASV) within the healthy Korean cohort, and their MAM sequences showed a high similarity of 98.6%. However, when a single strain was introduced to mice with dextran sulfate sodium (DSS)-induced colitis, KBL1027 showed the most significant ameliorative effects, including alleviation of colonic inflammation and restoration of gut microbial dysbiosis. Moreover, the supernatant from KBL1027 elevated the secretion of IL-10 cytokine more than that of KBL1026 in mouse bone marrow-derived macrophage (BMDM) cells, suggesting that the strain-specific, anti-inflammatory efficacy of KBL1027 might involve effector compounds other than MAM. Through analysis of the Faecalibacterium pan-genome and comparative genomics, strain-specific functions related to extracellular polysaccharide biosynthesis were identified in KBL1027, which could contribute to the observed morphological disparities. Collectively, our findings highlight the strain-specific, anti-inflammatory functions of F. prausnitzii, even within the same core ASV, emphasizing the influence of their human origin.

The Anti-Inflammatory and Curative Exponent of Probiotics: A Comprehensive and Authentic Ingredient for the Sustained Functioning of Major Human Organs

Several billion microorganisms reside in the gastrointestinal lumen, including viruses, bacteria, fungi, and yeast. Among them, probiotics were primarily used to cure digestive disorders such as intestinal infections and diarrhea; however, with a paradigm shift towards alleviating health through food, their importance is large. Moreover, recent studies have changed the perspective that probiotics prevent numerous ailments in the major organs. Probiotics primarily produce biologically active compounds targeting discommodious pathogens. This review demonstrates the implications of using probiotics from different genres to prevent and alleviate ailments in the primary human organs. The findings reveal that probiotics immediately activate anti-inflammatory mechanisms by producing anti-inflammatory cytokines such as interleukin (IL)-4, IL-10, IL-11, and IL-13, and hindering pro-inflammatory cytokines such as IL-1, IL-6, and TNF-α by involving regulatory T cells (Tregs) and T helper cells (Th cells). Several strains of Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus reuteri, Bifidobacterium longum, and Bifidobacterium breve have been listed among the probiotics that are excellent in alleviating various simple to complex ailments. Therefore, the importance of probiotics necessitates robust research to unveil the implications of probiotics, including the potency of strains, the optimal dosages, the combination of probiotics, their habitat in the host, the host response, and other pertinent factors.

Comparison of gut microbiota dysbiosis between pemphigus vulgaris and bullous pemphigoid

OBJECTIVE

Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are two prevalent bullous diseases. Previous studies found that the antibodies of BP could be expressed in the intestinal epithelium and BP was tightly related to inflammatory bowel disease. Therefore, gut microbiota might also play an important role in bullous disease. However, the specific relationship between gut microbiota and bullous diseases remains unknown. Our study aimed to investigate the potential role of gut microbiota in the development and progression of different bullous diseases.

METHODS

We conducted a prospective and observational cohort study at Peking Union Medical College Hospital. Untreated BP and PV patients were recruited, along with healthy controls (HC) who were spouses or caregivers of these patients. Fecal samples were collected, followed by 16S rRNA gene sequencing. Bioinformatics analyses were performed to assess the composition and function of gut microbiota.

RESULTS

A total of 38 HC, 32 BP, and 19 PV patients were enrolled in this study. Compared to HC, BP, and PV exhibited a distinct gut microbiota composition, especially BP. The gut microbiota changes were mainly observed in the phylum Bacteroidetes, Firmicutes, and Proteobacteria. The ratio of Faecalibacterium to Escherichia-Shigella (F/E ratio) had a considerable predictive value (AUC: 0.705) for recognizing BP from PV. The levels of Faecalibacterium and Enterobacter were correlated to the anti-BP 180 and anti-desmoglein 3. Microbial functional prediction revealed elevated activity in pathways related to gut microbiota translocation significantly increased in BP patients, indicating a potential pathogenetic role in BP.

CONCLUSIONS

Our study suggests that the composition of gut microbiota is specific in different bullous diseases and the role of gut microbiota differs. Gut microbiota could help distinguish BP and PV, and might play a role in the pathogenesis of different bullous diseases.

Gut Microbiome Changes in Anorexia Nervosa: A Comprehensive Review

Anorexia nervosa (AN) remains a challenging condition in psychiatric management and its pathogenesis is not yet fully understood. An imbalance in the gut microbiota composition may contribute to its pathophysiology. This review aims to explore the link between the human gut microbiota and AN (objective 1) or refeeding syndrome in AN (objective 2). The online databases MEDLINE and PsycINFO were searched for relevant studies. A total of 14 studies met the inclusion and exclusion criteria and only answered objective 1. A total of 476 AN patients, 554 healthy-weight (HC) controls, and 0 patients with other psychiatric disorders were included. Compared to HC, there were consistently reduced abundances of Faecalibacterium prausnitzii and Roseburia inulinivorans, and increased Methanobrevibacter smithii, in AN patients. Changes in alpha diversity were inconsistent, while beta diversity increased in four of six studies. Our model suggests that an imbalance in gut microbiota composition leads to reduced short-chain fatty acids, contributing to a proinflammatory state in AN, which is also common in other psychiatric comorbidities. Microbial changes may also contribute to the semistarvation state through endocrine changes and altered energy utilization.

Differential cytokine profiling and microbial species involved in cecal microbiota modulations in SPF chicks immunized with a dual vaccine against Salmonella Typhimurium infection

Salmonella Typhimurium (ST) infection in laying hens is a significant threat to public health and food safety. Host resistance against enteric pathogen invasion primarily relies on immunity and gut barrier integrity. This study applied the ST infection model and a dual live vaccine containing Salmonella Enteritidis (SE) strain Sm24/Rif12/Ssq and ST strain Nal2/Rif9/Rtt to investigate the cellular cytokine expression profiles and the differential community structure in the cecal microbiota of specific-pathogen-free (SPF) chicks and field-raised layers. The results showed that ST challenge significantly upregulated expressions of IL-1β in SPF chicks. Vaccination, on the other hand, led to an elevation in IFNγ expression and restrained IL-1β levels. In the group where vaccination preceded the ST challenge (S.STvc), heightened expressions of IL-1β, IL-6, IL-10, and IL-12β were observed, indicating active involvement of both humoral and cell-mediated immunity in the defense against ST. Regarding the cecal microbiota, the vaccine did not affect alpha diversity nor induce a significant shift in the microbial community. Conversely, ST infection significantly affected the alpha and beta diversity in the cecal microbiota, reducing beneficial commensal genera, such as Blautia and Subdoligranulum. MetagenomeSeq analysis reveals a significant increase in the relative abundance of Faecalibacterium prausnitzii in the groups (S.STvc and STvc) exhibiting protection against ST infection. LEfSe further demonstrated Faecalibacterium prausnitzii as the prominent biomarker within the cecal microbiota of SPF chicks and field layers demonstrating protection. Another biomarker identified in the S.STvc group, Eubacterium coprostanoligenes, displayed an antagonistic relationship with Faecalibacterium prausnitzii, suggesting the limited biological significance of the former in reducing cloacal shedding and tissue invasion. In conclusion, the application of AviPro Salmonella DUO vaccine stimulates host immunity and modulates cecal microbiota to defend against ST infection. Among the microbial modulations observed in SPF chicks and field layers with protection, Faecalibacterium prausnitzii emerges as a significant species in the ceca. Further research is warranted to elucidate its role in protecting layers against ST infection.

The effects of 6 wk of resistance training on the gut microbiome and cardiometabolic health in young adults with overweight and obesity

Obesity is a known risk factor for the development of insulin resistance and other cardiometabolic disorders. Recently, the gut microbiome has been associated with obesity and subsequent health complications. Exercise has been regularly utilized as a therapeutic intervention to treat obesity and its associated comorbidities. This study examined the effects of a 6-wk resistance training exercise program (RT) on the diversity, composition, and metabolic pathways of the gut microbiome. Sedentary young adults (age 18-35 yr) with overweight and obesity (BMI 25-45 kg/m2) were recruited to participate in this randomized controlled trial. Participants were randomized to RT (n = 16), a 6-wk resistance training program (3 days/wk), or control (CT) (n = 16), a nonexercising control. Main outcomes of the study included gut microbiome measures (taxa abundances, diversity, and predicted function) and cardiometabolic outcomes [blood pressure (BP) and glucoregulation]. Increased abundances of Roseburia, a short-chain fatty acid (SCFA) producer were observed over 6 wk (W6) with RT compared with CT (group × week, P < 0.05, q < 0.25). RT also induced marginal alterations in predicted microbial metabolic and cell motility pathways compared with CT (group × week, P < 0.05, q < 0.25). However, RT did not significantly impact overall microbial diversity. Furthermore, RT resulted in higher quantitative insulin-sensitivity check index (QUICKI) and lower diastolic BP at W6 compared with CT [baseline (BL)-adjusted P < 0.05]. RT had mixed effects on the gut microbiome. Although RT increased abundances of Roseburia and induced minor changes in microbial pathways, it is important to consider these changes in the context of the overall stability observed in the microbiome composition.NEW & NOTEWORTHY Resistance training induces mixed changes in the gut microbiome, including an increase in the abundances of the Roseburia genus and minor alterations in microbial pathways. However, it is vital to interpret these changes in light of the broader context, where we observe stability in the overall microbiome composition. This stability may be attributed to the microbiome's resilience, demonstrating its capacity to withstand short-term physiological stressors.

A Double-Blind Randomised Controlled Trial of Prebiotic Supplementation in Children with Autism: Effects on Parental Quality of Life, Child Behaviour, Gastrointestinal Symptoms, and the Microbiome

PURPOSE

Modifying gut bacteria in children with autism may influence behaviour, with potential to improve family functioning. We conducted a randomised controlled trial to assess the effect of prebiotics on behaviour, gastrointestinal symptoms and downstream effects on parental quality of life.

METHOD

Children with autism (4-10yrs) were randomised to 2.4 g/d of prebiotic (GOS) or placebo for six weeks. Pre and post stools samples were collected, and validated questionnaires used to measure change in social and mealtime behaviours, GI symptoms and pQOL. Linear mixed models evaluated group differences for behavioural variables, and Mann Whitney U tests were used to compare change between-groups for GI symptoms, differential abundance of genera and alpha diversity of the microbiome.

RESULTS

Thirty-three parent-child dyads completed the trial. No group difference was seen for behavioural variables but both groups improved significantly from baseline. There was a medium effect size between groups for GI symptoms (d = 0.47) and pQOL (d = 0.44) driven by greater improvements in the prebiotic group. Bifidobacterium increased threefold following prebiotics (1.4-5.9%, p < 0.001) with no change in controls. Supplements were well tolerated, compliance with dose 94%.

CONCLUSION

Prebiotics modify levels of Bifidobacterium and prove well tolerated but in this instance, resulted in only marginal effects on GI symptoms and pQOL. A larger sample of children with more severe symptoms could help to determine the potential of prebiotics in autism.

TRIAL REGISTRATION

https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12619000615189 .

Preliminary study of the effect of gut microbiota on the development of prostatitis

BACKGROUND

Dysbacteriosis of intestinal tract may cause systemic inflammation, making distant anatomical locations more susceptible to illness. Recent research has demonstrated that the microbiome can affect both prostatitis and the inflammation of the prostate that is linked to prostate cancer. It is still unclear, though, whether this relationship indicates causation. We conducted a Mendelian randomization investigation on two samples to fully uncover gut microbiota's potential genetic causal role in prostatitis.

METHOD

Prostatitis (1859 prostatitis cases and 72,799 controls) was utilized as the outcome, while SNPs highly linked with 196 microbial taxa (18 340 people) were chosen as instrumental factors. Random effects, inverse variance weighting, weighted medians, and MR-Egger were used to analyze causal effects. The Cochran's Q test, funnel plot, leave-one-out analysis, and MR-Egger intercept test were all used in the sensitivity analysis.

RESULTS

A causal effect in lowering the incidence of prostatitis is anticipated for five gut microorganisms (Methanobacteria, Methanobacteriaceae, Erysipelatoclostridium, Parasutterella, and Slackia; P < 0.05). Four gut bacteria, including Faecalibacterium, LachnospiraceaeUCG004, Sutterella, and Gastranaerophilales, are predicted to play a causal role in increasing the risk of prostatitis (P < 0.05). There were no discernible estimates of pleiotropy or heterogeneity.

CONCLUSION

Our investigation established the genetic links between nine gut microorganisms and prostatitis, which may offer fresh perspectives and a theoretical framework for the future prevention and management of prostatitis.

Dynamic changes in the migratory microbial components of colon tissue during different periods of sepsis in an LPS-induced rat model

Previous studies have shown that bacterial translocation may play an important role in worsening gastrointestinal injury during sepsis. However, the dynamics of specific microbiota components in intestinal tissues at different sepsis stages remain unclear. Rats receiving intraperitoneal lipopolysaccharide (LPS) were sacrificed at 12 h and 48 h post-injection. Routine blood, serum cytokines, and microbiota in colon tissue, colonic contents, and lung tissue at different time points were assessed. Migratory microbial components in colonic tissue at 12 h and 48 h post-LPS were identified using source tracking, characteristic component identification, and abundance difference analyses. Colonic tissue microbiota changed dynamically over time after LPS injection, involving translocation of microbial components from colon contents and lung tissue at different time points. Bacteria migrating to colon tissue at 12 h sepsis were mainly from colonic contents, while those at 48 h were predominantly from the lung tissue. The migratory microbial components in colon tissue were widely associated with blood indicators and colonizing genus abundance and microbiota functionality in colon tissue. In this study, the temporal dynamics of bacterial translocation from various sources into colon tissues at different sepsis progression stages were characterized for the first time, and the species composition of these migrating microbes was delineated. These bacterial migrants may contribute to the pathophysiological processes in sepsis through direct interactions or indirectly by modulating colonic microbiota community structure and function.

Comparative analysis of metagenomic classifiers for long-read sequencing datasets

BACKGROUND

Long reads have gained popularity in the analysis of metagenomics data. Therefore, we comprehensively assessed metagenomics classification tools on the species taxonomic level. We analysed kmer-based tools, mapping-based tools and two general-purpose long reads mappers. We evaluated more than 20 pipelines which use either nucleotide or protein databases and selected 13 for an extensive benchmark. We prepared seven synthetic datasets to test various scenarios, including the presence of a host, unknown species and related species. Moreover, we used available sequencing data from three well-defined mock communities, including a dataset with abundance varying from 0.0001 to 20% and six real gut microbiomes.

RESULTS

General-purpose mappers Minimap2 and Ram achieved similar or better accuracy on most testing metrics than best-performing classification tools. They were up to ten times slower than the fastest kmer-based tools requiring up to four times less RAM. All tested tools were prone to report organisms not present in datasets, except CLARK-S, and they underperformed in the case of the high presence of the host's genetic material. Tools which use a protein database performed worse than those based on a nucleotide database. Longer read lengths made classification easier, but due to the difference in read length distributions among species, the usage of only the longest reads reduced the accuracy. The comparison of real gut microbiome datasets shows a similar abundance profiles for the same type of tools but discordance in the number of reported organisms and abundances between types. Most assessments showed the influence of database completeness on the reports.

CONCLUSION

The findings indicate that kmer-based tools are well-suited for rapid analysis of long reads data. However, when heightened accuracy is essential, mappers demonstrate slightly superior performance, albeit at a considerably slower pace. Nevertheless, a combination of diverse categories of tools and databases will likely be necessary to analyse complex samples. Discrepancies observed among tools when applied to real gut datasets, as well as a reduced performance in cases where unknown species or a significant proportion of the host genome is present in the sample, highlight the need for continuous improvement of existing tools. Additionally, regular updates and curation of databases are important to ensure their effectiveness.

Combination of Coptis chinensis polysaccharides and berberine ameliorates ulcerative colitis by regulating gut microbiota and activating AhR/IL-22 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Coptis chinensis Franch. polysaccharide (CCP) and berberine (BBR) are the primary active components of Coptis chinensis Franch. BBR is clinically used for the treatment of intestinal infections and gastroenteritis. CCP was also reported to be effective for the treatment of ulcerative colitis (UC). However, whether CCP combined with BBR shows a synergistic effect on the treatment of UC has not been elucidated yet.

AIM OF THE STUDY

This study aspired to investigate the therapeutic effect and the possible mechanisms of the combination of CCP with BBR on chronic UC.

MATERIALS AND METHODS

By periodic administration of dextran sulfate sodium (DSS) to C57BL/6J mice, chronic UC model mice were induced. CCP (15 mg/kg), BBR (50 mg/kg), and CCP.BBR (a combination of 15 mg/kg CCP and 50 mg/kg BBR) were orally administered to the model mice for 10 days. Changes of body weight, disease activity index, colon length, organ index, histopathological damage, expression of cytokines, and intestinal tight junction proteins were determined to evaluate the therapeutic effects. 16S rDNA sequencing, targeted short-chain fatty acid metabolomics, qPCR, and western blotting were performed to elucidate the potential mechanism.

RESULTS

Both CCP and BBR alleviated UC via improving colon pathological damage, inhibiting the inflammatory response, and regulating the expression of intestinal tight junction proteins. The combination of CCP with BBR showed a more substantial therapeutic effect via increasing the relative abundance of short-chain fatty acids (SCFAs) producing bacteria, thereby increasing the contents of SCFAs in vivo and activating AhR/IL-22 pathway.

CONCLUSION

The combination of CCP and BBR showed a synergistic effect on the therapy of chronic UC and the mechanism was associated with regulating gut microbiota and activating AhR/IL-22 pathway.

Linking active rectal mucosa-attached microbiota to host immunity reveals its role in host-pathogenic STEC O157 interactions

The rectal-anal junction (RAJ) is the major colonization site of Shiga toxin-producing Escherichia coli (STEC) O157 in beef cattle, leading to transmission of this foodborne pathogen from farms to food chains. To date, there is limited understanding regarding whether the mucosa-attached microbiome has a profound impact on host-STEC interactions. In this study, the active RAJ mucosa-attached microbiota and its potential role in host immunity-STEC commensal interactions were investigated using RAJ mucosal biopsies collected from calves orally challenged with two STEC O157 strains with or without functional stx2a (stx2a+ or stx2a-). The results revealed that shifts of microbial diversity, topology, and assembly patterns were subjected to stx2a production post-challenge and Paeniclostridium and Gallibacterium were the keystone taxa for both microbial interactions and assembly. Additional mucosal transcriptome profiling showed stx2a-dependent host immune responses (i.e. B- and T-cell signaling and antigen processing and presentation) post-challenge. Further integrated analysis revealed that mucosa-attached beneficial microbes (i.e. Provotella, Faecalibacterium, and Dorea) interacted with host immune genes pre-challenge to maintain host homeostasis; however, opportunistic pathogenic microbes (i.e. Paeniclostridium) could interact with host immune genes after the STEC O157 colonization and interactions were stx2a-dependent. Furthermore, predicted bacterial functions involved in pathogen (O157 and Paeniclostridium) colonization and metabolism were related to host immunity. These findings suggest that during pathogen colonization, host-microbe interactions could shift from beneficial to opportunistic pathogenic bacteria driven and be dependent on the production of particular virulence factors, highlighting the potential regulatory role of mucosa-attached microbiota in affecting pathogen-commensal host interactions in calves with STEC O157 infection.

Effect of Saccharomyces cerevisiae Postbiotics and Essential Oil on Growth Performance and Intestinal Health of Weanling Pigs During K88 ETEC Infection

Enterotoxigenic Escherichia coli (ETEC) is one of the major bacterial infections, causing substantial economic losses globally in the swine industry. This study aimed to investigate the impact of low Saccharomyces cerevisiae fermentation postbiotics (SCFP), high SCFP, essential oil (EO), or their combination on the growth performance and health of weanling pigs during ETEC infection. Forty-eight male weanling pigs were randomly allocated to five groups: 1) control group (CON-basal diet, n = 16); 2) low SCFP group (LSC-basal diet + 1.25 g/kg SCFP, n = 8); 3) high SCFP group (HSC-basal diet + 2 g/kg SCFP, n = 8); 4) essential oil group (EO-basal diet + 0.4 g/kg EO, n = 8); 5) the SCFP and EO combination group (SE-basal diet + 1.25 g/kg SCFP + 0.4 g/kg EO, n = 8). On day 15 of the trial, pigs in CON were divided into positive control (PC) and negative control (NC), and all pigs, except in NC, were challenged with ETEC. Under the normal condition, dietary LSC, HSC, EO, and EO all increased average daily gain (ADG) (P < 0.05), and decreased F:G ratio (P < 0.05) accompanied by decreased malondialdehyde (MDA) and increases in catalase (CAT), total superoxide dismutase (T-SOD), total antioxidant capacity (T-AOC) indicating enhanced anti-oxidative capacity, as well as decreased IL-2, IL-8, INF-γ, indicating mitigated systemic inflammation. During ETEC infection, all treatments alleviated ETEC-induced ADG reduction, diarrhea, damages in intestinal permeability and morphology, and down-regulation of tight junctions (Claudin1, ZO-1, and Occludin), while HSC and EO exhibited additional protections. All treatments increased CAT, T-SOD, and T-AOC, and decreased MDA in serum and jejunal mucosa at similar degrees (P < 0.05). Moreover, all treatments alleviated ETEC-induced inflammation as shown by decreased IL-6, TNF-α, INF-γ, and increased IL-4 and IL-10 in serum or jejunal mucosa (P < 0.05), and enhanced the immunity by increased serum IgG and mucosal sIgA (P < 0.05). HSC and SE further reduced mucosal INF-γ and TNF-α than LSC or EO aligning with their additional protection against diarrhea during ETEC infection. Additionally, the key gut bacteria (e.g., Terrisporobacter) related to the benefits of SCFP and EO were identified. In sum, all treatments enhanced growth performance and protected against ETEC-induced intestinal damage through the regulation of redox and immune homeostasis. HSP and SE offered extra protection during disease for their additional control of inflammation. Our study provided new insight into the use of feed additives in the context of animal health states.

Oral histidine affects gut microbiota and MAIT cells improving glycemic control in type 2 diabetes patients

Amino acids, metabolized by host cells as well as commensal gut bacteria, have signaling effects on host metabolism. Oral supplementation of the essential amino acid histidine has been shown to exert metabolic benefits. To investigate whether dietary histidine aids glycemic control, we performed a case-controlled parallel clinical intervention study in participants with type 2 diabetes (T2D) and healthy controls. Participants received oral histidine for seven weeks. After 2 weeks of histidine supplementation, the microbiome was depleted by antibiotics to determine the microbial contribution to histidine metabolism. We assessed glycemic control, immunophenotyping of peripheral blood mononucelar cells (PBMC), DNA methylation of PBMCs and fecal gut microbiota composition. Histidine improves several markers of glycemic control, including postprandial glucose levels with a concordant increase in the proportion of MAIT cells after two weeks of histidine supplementation. The increase in MAIT cells was associated with changes in gut microbial pathways such as riboflavin biosynthesis and epigenetic changes in the amino acid transporter SLC7A5. Associations between the microbiome and MAIT cells were replicated in the MetaCardis cohort. We propose a conceptual framework for how oral histidine may affect MAIT cells via altered gut microbiota composition and SLC7A5 expression in MAIT cells directly and thereby influencing glycemic control. Future studies should focus on the role of flavin biosynthesis intermediates and SLC7A5 modulation in MAIT cells to modulate glycemic control.

Bacterial distribution and inflammatory cytokines associated with oral cancer with and without jawbone invasion-a pilot study

OBJECTIVE

To explore the bacterial and inflammatory variations in oral cancer patients with and without jawbone invasion.

MATERIALS AND METHODS

A total of 20 specimens of fresh tumor tissue, including 10 from the tumor-invaded jawbone (JIOC group) and 10 without jawbone invasion (NJIOC group), were collected from oral cancer patients. Meanwhile, 10 specimens from normal oral mucosa were collected from healthy patients (control group). The microbiomic content of each sample was analyzed by 16S rRNA gene sequencing, while the expression of inflammatory cytokines was assessed using protein microarray analysis.

RESULTS

There was a significant difference in β diversity between JIOC and NJIOC groups (P < 0.05), but no difference between NJIOC and control groups. The average relative abundance of Fusobacteria and Spirochaetes was higher, while Firmicutes was lower in the JIOC group than in the NJIOC group (all P < 0.05). The expression of pro-inflammatory cytokines like interleukin (IL)-1α, IL-1β, IL-4, and IL-8 was upregulated in the JIOC group compared with the NJIOC group, while MCP-1 was decreased (all P < 0.05). Slackia spp. and Howardella spp. were positively correlated with IL-4; Odoribacter spp. and Acidaminococcaceae spp. were negatively correlated with IL-4, and Clostridium XIVa spp. was negatively correlated with IL-1α and IL-1β.

CONCLUSION

Bacterial and inflammatory differences were observed in oral cancer patients with and without jawbone invasion, where the relative abundance of the differential bacteria was associated with the expression of the inflammatory cytokines.

CLINICAL RELEVANCE

This study investigated the changes in the flora during jawbone invasion in oral cancer and its effect on inflammatory factors, elucidating the possible mechanisms of jawbone invasion caused by oral cancer, which may lead to new ideas for the clinical prevention and treatment of jawbone invasion in oral cancer.

Gut microbiota changes in patients with hypertension: A systematic review and meta-analysis

Hypertension is a major public health issue worldwide. The imbalance of gut microbiota is thought to play an important role in the pathogenesis of hypertension. The authors conducted the systematic review and meta-analysis to clarify the relationship between gut microbiota and hypertension through conducting an electronic search in six databases. Our meta-analysis included 19 studies and the results showed that compared with healthy controls, Shannon significantly decreased in hypertension [SMD = -0.13, 95%CI (-0.22, -0.04), p = .007]; however, Simpson [SMD = -0.01, 95%CI (-0.14, 0.12), p = .87], ACE [SMD = 0.18, 95%CI (-0.06, 0.43), p = .14], and Chao1 [SMD = 0.11, 95%CI (-0.01, 0.23), p = .08] did not differ significantly between hypertension and healthy controls. The F/B ratio significantly increased in hypertension [SMD = 0.84, 95%CI (0.10, 1.58), p = .03]. In addition, Shannon index was negatively correlated with hypertension [r = -0.12, 95%CI (-0.19, -0.05)], but had no significant correlation with SBP [r = 0.10, 95%CI (-0.19, 0.37)] and DBP [r = -0.39, 95%CI (-0.73, 0.12)]. At the phylum level, the relative abundance of Firmicutes [SMD = -0.01, 95%CI (-0.37, 0.34), p = .94], Bacteroidetes [SMD = -0.15, 95%CI (-0.44, 0.14), p = .30], Proteobacteria [SMD = 0.25, 95%CI (-0.01, 0.51), p = .06], and Actinobacteria [SMD = 0.21, 95%CI (-0.11, 0.53), p = .21] did not differ significantly between hypertension and healthy controls. At the genus level, compared with healthy controls, the relative abundance of Faecalibacterium decreased significantly [SMD = -0.16, 95%CI (-0.28, -0.04), p = .01], while the Streptococcus [SMD = 0.20, 95%CI (0.08, 0.32), p = .001] and Enterococcus [SMD = 0.20, 95%CI (0.08, 0.33), p = .002] significantly increased in hypertension. Available evidence suggests that hypertensive patients may have an imbalance of gut microbiota. However, it still needs further validation by large sample size studies of high quality.

Comparative analysis of changes in diarrhea and gut microbiota in Beigang pigs

Increasing evidence indicated that the gut microbiota is a large and complex organic combination, which is closely related to the host health. Diarrhea is a disease with devastating effects on livestock that has been demonstrated to be associated with gut microbiota. Currently, studies on gut microbiota and diarrhea have involved multiple species, but changes in gut microbiota of Beigang pigs during diarrhea have not been characterized. Here, we described gut microbial changes of Beigang pigs during diarrhea. Results indicated that a total of 4423 OTUs were recognized in diarrheic and healthy Beigang pigs, and Firmicutes and Bacteroidota were the most dominant phyla regardless of health status. However, the major components of the gut microbiota changed between diarrheic and healthy Beigang pigs. Bacterial taxonomic analysis revealed that the relative abundances of 3 phyla (Synergistota, Actinobacteriota and Spirochaetota) and 30 genera increased significantly during diarrhea, whereas the relative abundances of 3 phyla (Patescibacteria, Bacteroidota and Fibrobacterota) and 41 genera decreased significantly. In conclusion, this study found significant changes in the gut microbiota of Beigang pigs during diarrhea. Meanwhile, this also lays the foundation for the prevention and treatment of diarrhea in Beigang pigs and the further discovery of more anti-diarrhea probiotics.

Effects of Yupingfeng Polysaccharides as Feed Supplement on Immune Function and Intestinal Microbiome in Chickens

The health of chicks is closely related to their productivity. Yupingfeng polysaccharide (YPF-P) is a kind of water-soluble polysaccharide extracted from Yupingfeng powder; it has high pharmacological activity and can be used as a potential substitute for antibiotics to improve the health of chicks. This study aimed to investigate the effects of YPF-P on immune performance, the duodenum, and the cecal microflora of chicks. All chickens (4224) were randomly distributed into four groups (eight replicas/group, 132 hens/replica). The control group was fed a basal diet (0 g/kg YPF-P), while the experimental groups were fed basal diets supplemented with 1, 2, or 4 g/kg YPF-P. The results showed that YPF-P significantly increased the thymus index (p < 0.05). The content of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), immunoglobulin A (IgA), and IgG and immunoglobulin M (IgM) was upregulated in the serum by YPF-P (p < 0.05). YPF-P decreased the content of malondialdehyde (MDA) (p < 0.05). Further, 16S rRNA sequencing showed that 2 g/kg YPF-P modulated the predominant duodenum and cecal microbial community structure, which increased the number of Faecalibacterium, Megamonas, Bacteroides, Alistipes, NK4A214_group, and Enterococcus. In conclusion, YPF-P ameliorated the growth performance of chicks by regulating serum immune and antioxidant balance, as well as the intestinal microbiota.

Exploring the role of gut microbiota in autoimmune thyroid disorders: a systematic review and meta-analysis

Background

Autoimmune thyroid diseases (AITDs) are characterized by unique immune responses against thyroid antigens and persist over time. The most common types of AITDs are Graves' disease (GD) and Hashimoto's thyroiditis (HT). There is mounting evidence that changes in the microbiota may play a role in the onset and development of AITDs.

Objective

The purpose of this comprehensive literature study was to answer the following query: Is there a difference in microbiota in those who have AITDs?

Methods

According to the standards set out by the PRISMA statement, 16 studies met the requirements for inclusion after being screened for eligibility.

Results

The Simpson index was the only diversity measure shown to be considerably lower in patients with GD compared to healthy participants, whereas all other indices were found to be significantly greater in patients with HT. The latter group, however, showed a greater relative abundance of Bacteroidetes and Actinobacteria at the phylum level, and consequently of Prevotella and Bifidobacterium at the genus level. The strongest positive and negative relationships were seen for thyroid peroxidase antibodies and bacterial load.

Conclusion

Overall, both GD and HT patients showed significant changes in the gut microbiota's diversity and composition.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023432455.

Gut Microbiota in Diagnosis, Therapy and Prognosis of Cholangiocarcinoma and Gallbladder Carcinoma-A Scoping Review

Cancers of the biliary tract are more common in Asia than in Europe, but are highly lethal due to delayed diagnosis and aggressive tumor biology. Since the biliary tract is in direct contact with the gut via the enterohepatic circulation, this suggests a potential role of gut microbiota, but to date, the role of gut microbiota in biliary tract cancers has not been elucidated. This scoping review compiles recent data on the associations between the gut microbiota and diagnosis, progression and prognosis of biliary tract cancer patients. Systematic review of the literature yielded 154 results, of which 12 studies and one systematic review were eligible for evaluation. The analyses of microbiota diversity indices were inconsistent across the included studies. In-depth analyses revealed differences between gut microbiota of biliary tract cancer patients and healthy controls, but without a clear tendency towards particular species in the studies. Additionally, most of the studies showed methodological flaws, for example non-controlling of factors that affect gut microbiota. At the current stage, there is a lack of evidence to support a general utility of gut microbiota diagnostics in biliary tract cancers. Therefore, no recommendation can be made at this time to include gut microbiota analyses in the management of biliary tract cancer patients.

Composition and evolution of the gut microbiota of growing puppies is impacted by their birth weight

Low birth weight puppies present an increased risk of neonatal mortality, morbidity, and some long-term health issues. Yet it has not been investigated if those alterations could be linked to the gut microbiota composition and evolution. 57 puppies were weighed at birth and rectal swabs were performed at 5 time points from birth to 28 days of age. Puppies were grouped into three groups based on their birth weight: low birth weight (LBW), normal birth weight (NBW) and high birth weight (HBW). 16S rRNA gene sequencing was used to highlight differences in the fecal microbiota. During the first three weeks, the relative abundance of facultative anaerobic bacteria such as E. coli, C. perfringens and Tyzzerella was higher in LBW feces, but they catch back with the other groups afterwards. HBW puppies showed higher abundances of Faecalibacterium and Bacteroides during the neonatal period, suggesting an earlier maturation of their microbiota. The results of this study suggest that birth weight impact the initial establishment of the gut microbiota in puppies. Innovative strategies would be desired to deal with altered gut microbiota in low birth weight puppies aiming to improve their survival and long term health.

Bacterial dysbiosis and epithelial status of the California sea lion (Zalophus californianus) in the Gulf of California

Despite the high incidence of urogenital carcinoma (UGC) in California sea lions stranded along California, no UGC has been reported in other areas of their distribution; however, cell morphologies typical of premalignant states have been found. Risk factors for UGC include high of organochlorines and infection with a gammaherpesvirus, OtHV-1, but the importance of the bacteriome for epithelial status remains unknown. We characterized the genital bacteriome of adult female California sea lions along their distribution in the Gulf of California and examined whether the diversity and abundance of the bacteriome varied spatially, whether there were detectable differences in the bacteriome between healthy and altered epithelia, and whether the bacteriome was different in California sea lions infected with OtHV-1 or papillomavirus. We detected 2270 ASVs in the genital samples, of which 35 met the criteria for inclusion in the core bacteriome. Fusobacteriia and Clostridia were present in all samples, at high abundances, and Actinobacteria, Alphaproteobacteria, and Campylobacteria were also well-represented. Alpha diversity and abundance of the California sea lion genital bacteriome varied geographically. The abundance of bacterial ASVs varied depending on the genital epithelial status and inflammation, with differences driven by classes Fusobacteriia, Clostridia, Campylobacteria and Alphaproteobacteria. Alpha diversity and abundance were lowest in samples in which OtHV-1 was detected, and highest those with papillomavirus. Our study is the first investigation of how the bacteriome is related to epithelial status in a wild marine species prone to developing cancer.

Intestinal bacteria associated with irritable bowel syndrome and chronic fatigue

The etiology of irritable bowel syndrome (IBS) is unknown. Abnormal intestinal bacterial profiles and low bacterial diversity appear to play important roles in the pathophysiology of IBS. This narrative review was designed to present recent observations made relating to fecal microbiota transplantation (FMT), which implicate possible roles of 11 intestinal bacteria in the pathophysiology of IBS. The intestinal abundances of nine of these bacteria increased after FMT in patients with IBS, and these increases were inversely correlated with IBS symptoms and fatigue severity. These bacteria were Alistipes spp., Faecalibacterium prausnitzii, Eubacterium biforme, Holdemanella biformis, Prevotella spp., Bacteroides stercoris, Parabacteroides johnsonii, Bacteroides zoogleoformans, and Lactobacillus spp. The intestinal abundances of two bacteria were decreased in patients with IBS after FMT and were correlated with the severity of IBS symptoms and fatigue (Streptococcus thermophilus and Coprobacillus cateniformis). Ten of these bacteria are anaerobic and one (Streptococcus thermophilus) is facultative anaerobic. Several of these bacteria produce short-chain fatty acids, especially butyrate, which is used as an energy source by large intestine epithelial cells. Moreover, it modulates the immune response and hypersensitivity of the large intestine and decreases intestinal cell permeability and intestinal motility. These bacteria could be used as probiotics to improve these conditions. Protein-rich diets could increase the intestinal abundance of Alistipes, and plant-rich diet could increase the intestinal abundance of Prevotella spp., and consequently improve IBS and fatigue.

Recent progress in plant-derived polysaccharides with prebiotic potential for intestinal health by targeting gut microbiota: a review

Natural products of plant origin are of high interest and widely used, especially in the food industry, due to their low toxicity and wide range of bioactive properties. Compared to other plant components, the safety of polysaccharides has been generally recognized. As dietary fibers, plant-derived polysaccharides are mostly degraded in the intestine by polysaccharide-degrading enzymes secreted by gut microbiota, and have potential prebiotic activity in both non-disease and disease states, which should not be overlooked, especially in terms of their involvement in the treatment of intestinal diseases and the promotion of intestinal health. This review elucidates the regulatory effects of plant-derived polysaccharides on gut microbiota and summarizes the mechanisms involved in targeting gut microbiota for the treatment of intestinal diseases. Further, the structure-activity relationships between different structural types of plant-derived polysaccharides and the occurrence of their prebiotic activity are further explored. Finally, the practical applications of plant-derived polysaccharides in food production and food packaging are summarized and discussed, providing important references for expanding the application of plant-derived polysaccharides in the food industry or developing functional dietary supplements.

Dysbiosis of gut microbiota during fecal stream diversion in patients with colorectal cancer

BACKGROUND

The effect of fecal stream diversion on the gut microbiota is still uncertain. The present study was designed to assess the effect of fecal stream diversion on the composition of the gut microbiota in patients with colorectal cancer. We included patients undergoing left-sided colorectal cancer surgery with (ileostomy group) or without (control group) diverting ileostomy. Fecal samples were collected from 10 patients in each group before surgery (t1) and after ileostomy repair in the ileostomy group and 6-12 months after the initial surgery in the control group (t2). The fecal microbiota was assessed using 16S rRNA sequencing, and changes in the composition of the fecal microbiota were compared between the two groups.

RESULTS

Alpha diversity analysis revealed that the complexity of fecal microbiota decreased between t1 and t2 only in the ileostomy group. Beta diversity analysis also showed dissimilarity between t1 and t2 only in the ileostomy group. The composition of the microbiota was similar between the two groups at t1. However, at t2, the ileostomy group had lower proportion of beneficial bacteria (Lachnospiraceae, 3.8% vs. 29.9%, p < 0.001; Ruminococcaceae, 0.6% vs. 18.4%, p < 0.001; Blautia, 0.1% vs. 9.1%, p < 0.001; Faecalibacterium, 0.2% vs. 7.5%, p < 0.001) and a higher proportion of harmful bacteria (Proteobacteria, 17.9% vs. 5.1%, p = 0.006; Clostridium, 16.2% vs. 1.1%, p = 0.013; Streptococcus, 17.7% vs. 1.6%, p = 0.002) than the control group.

CONCLUSIONS

Fecal stream diversion was closely associated with less diversity and dysbiosis of the gut microbiota.