Fecal Transplantation Research Articles

Probiotics as adjuvants to mitigate adverse reactions and enhance effectiveness in Food Allergy Immunotherapy.

In the past decades, food allergies became increasingly dominant since early childhood, leading to a lower quality of life and to increasing costs addressed by the health care system. Beside standard avoidance of specific allergens and drug treatments following allergen exposure, a great deal of research has lately focused on Food Allergy Allergen Immunotherapy (FA-AIT). SCIT and EPIT (Subcutaneous and Epicutaneous Immunotherapy), OIT (Oral Immunotherapy), and SLIT (Sublingual Immunotherapy) consist in gradual exposure to allergens to desensitize and achieve tolerance once therapy has ended. Although promising, FA-AIT may bring acute local and systemic adverse reactions. To enhance efficacy, safety and convenience of AIT, the quest of potential adjuvants to mitigate the adverse reactions becomes crucial. Immunomodulatory activities, such as that of increasing the regulatory T cells and decreasing the IgE, have been observed in specific probiotics' strains and multiple studies elucidated the role of gut microbiota as a major interplayer among the host and its immune system. In this review, the microbiome modulation is shown as potential AIT adjuvant, nevertheless the need of more clinical studies in the near future is pivotal to assess the efficacy of targeted bacterial therapies and faecal microbiota transplantation.

Kui-Jie-Ling capsule inhibits ulcerative colitis by modulating inflammation and gut microbiota.

Kui-Jie-Ling capsule (Kui-Jie-Ling) is a hospital preparation for ulcerative colitis (UC) in China. This study aimed at evaluating the protective effects and mechanisms of Kui-Jie-Ling and Kui-Jie-Ling combined with adalimumab on UC induced by dextran sulfate sodium (DSS). Network pharmacology was combined with an animal experiment to reveal the targets of Kui-Jie-Ling alleviating UC. The UC model was established by drinking 2.5% DSS solution for 7days. On the second day, the mice in the Kui-Jie-Ling group were orally administered with Kui-Jie-Ling (1.5 and 3.0g/kg) daily for seven consecutive days, and the mice in the combination group were orally administered with Kui-Jie-Ling (3.0g/kg) once a day for seven consecutive days and received one subcutaneous injection of adalimumab. The disease activity index, the colon length, the spleen index, the cytokines, the colon, the short-chain fatty acid content, and the gut microbiota in the colon were analyzed. The role of gut microbiota against UC was verified by fecal microbiota transplantation experiments. The animal study's results were consistent with the network pharmacology analysis, which reflected that Kui-Jie-Ling alleviated UC via multi-pathway. Kui-Jie-Ling ameliorated UC by inhibiting the formation of neutrophil extracellular traps (NETs), regulating inflammatory factors through the lipopolysaccharide-toll-like receptor 4/nuclear factor kappa B and interleukin-23-Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway, and restoring intestinal homeostasis. These studies provided the experimental basis for the clinical administration of Kui-Jie-Ling and Kui-Jie-Ling combined with adalimumab against UC.

Transplantation of fecal microbiota from different breed improved intestinal barrier condition and modulated ileal microflora of recipient pigs.

In this study, we investigated the effects of transplanting Ningxiang pig fecal bacteria on ileum microflora and intestinal barrier of Duroc × Landrace × Large White (DLY) pigs. Thirty-two DLY pigs at 90-d-old were equally assigned to either control groups (fed the basal diet) or test group (fed the basal diet + 10ml fecal microbiota suspension from Ningxiang pig). Results showed that fecal microbiota transplantation (FMT) did not influence the growth performance, but increased the number of ileum goblet cells and the expression level of mucin-2. Additionally, the mucosal levels of anti-inflammatory cytokines interlukin-4 and interlukin-10 were upregulated, but the level of pro-inflammatory cytokine interferon-γ was downregulated by FMT. Moreover, FMT increased the expression level of porcine β defensin-114 in ileum mucus. 16S rRNA gene sequencing of ileal digesta showed that FMT modulated the diversity and composition of ileal microbiota of DLY pigs by increasing the relative abundances of beneficial bacteria, while decreasing the abundance of the pathogenic bacterium Streptococcus. Taken together, the study showed that FMT of Ningxiang pigs could improve intestinal barrier condition of DLY pigs by improving intestinal microflora and promoting intestinal health.

Unveiling the Potential of Gut Microbiota: Promising Approaches to Treat Drug-Resistant Epilepsy

Introduction: Epilepsy is a chronic, non-infectious disease of the brain. Data shows that even 70 million people worldwide suffer from it and one-third of them fail to control it with anti-epileptic drugs. The gut microbiota has an impact on the course of the disease. The microbiota mediates between the gastrointestinal system and the central nervous system.Purpose: The aim of the work is to analyse how modification of the gut microbiota affects patients with drug-resistant epilepsy.Material and method: In December 2023, an extensive search was conducted and articles found in the Medline (PubMed) databases were selected by using the following keywords: drug-resistant epilepsy, gut microbiota, gut-brain axis, ketogenic diet, probiotics, faecal microbiota transplantation, to focus on recent developments and advancements in the field, the search was limited to articles published between 2017 and 2023.Conclusions: The intestinal microbiota in drug-resistant epilepsy (DRE) patients differs from that of healthy individuals or drug-sensitive epilepsy patients. Acknowledging the presence of the gut-brain axis and its impact on the central nervous system, we can view altering the flora as a potential therapeutic approach for DRE patients. The ways in which microbiota changes have been confirmed by research include: ketogenic diet, antibiotics, probiotics and fecal microbiota transplantation (FMT). Modifying the microbiota through these mentioned methods is all promising for treating DRE.

The Gut Microbiome in Sepsis: From Dysbiosis to Personalized Therapy

Sepsis is a complex clinical syndrome characterized by an uncontrolled inflammatory response to an infection that may result in septic shock and death. Recent research has revealed a crucial link between sepsis and alterations in the gut microbiota, showing that the microbiome could serve an essential function in its pathogenesis and prognosis. In sepsis, the gut microbiota undergoes significant dysbiosis, transitioning from a beneficial commensal flora to a predominance of pathobionts. This transformation can lead to a dysfunction of the intestinal barrier, compromising the host’s immune response, which contributes to the severity of the disease. The gut microbiota is an intricate system of protozoa, fungi, bacteria, and viruses that are essential for maintaining immunity and metabolic balance. In sepsis, there is a reduction in microbial heterogeneity and a predominance of pathogenic bacteria, such as proteobacteria, which can exacerbate inflammation and negatively influence clinical outcomes. Microbial compounds, such as short-chain fatty acids (SCFAs), perform a crucial task in modulating the inflammatory response and maintaining intestinal barrier function. However, the role of other microbiota components, such as viruses and fungi, in sepsis remains unclear. Innovative therapeutic strategies aim to modulate the gut microbiota to improve the management of sepsis. These include selective digestive decontamination (SDD), probiotics, prebiotics, synbiotics, postbiotics, and fecal microbiota transplantation (FMT), all of which have shown potential, although variable, results. The future of sepsis management could benefit greatly from personalized treatment based on the microbiota. Rapid and easy-to-implement tests to assess microbiome profiles and metabolites associated with sepsis could revolutionize the disease’s diagnosis and management. These approaches could not only improve patient prognosis but also reduce dependence on antibiotic therapies and promote more targeted and sustainable treatment strategies. Nevertheless, there is still limited clarity regarding the ideal composition of the microbiota, which should be further characterized in the near future. Similarly, the benefits of therapeutic approaches should be validated through additional studies.

Therapeutic effects of fecal microbial transplantation on alcoholic liver injury in rat models

ObjectiveDisruption of gut microbiota is closely related to the progression of alcoholic liver disease (ALD). This study aimed to explore the therapeutic effect of fecal microbiota transplantation (FMT) in ALD rats using a combination of microbiological and metabolomic techniques. MethodsThree liver injury rat models were constructed using alcohol, CCL4, and alcohol combined with CCL4, and administered an FMT treatment comprising the fecal microbiota of healthy rats via the gastric route for 12 consecutive weeks. We measured the therapeutic effect of FMT treatment on liver inflammation, intestinal mucosal barrier, and bacterial translocation in ALD rats using 16S rRNA and UPLC-Q/TOF-MS technology to detect the effects of FMT on the intestinal microbiota and metabolic patterns of ALD rats. ResultsFMT treatment effectively improved liver function, prolonged survival time, improved the intestinal mucosal barrier, reduced bacterial translocation, alleviated liver inflammation, and delayed the progression of liver fibrosis in three types of liver injury models. The microbiome and metabolomic results showed that FMT can effectively improve gut microbiota disorder in ALD rats and improve metabolic patterns by regulating metabolic pathways such as the arachidonic acid and retinol pathways. ConclusionFMT treatment could reverse alcohol induced liver injury by improving gut microbiota and metabolic patterns in ALD rats, and oral FMT could be an effective therapeutic approach for ALD.

Dietary Dihydroquercetin Alleviated Colitis via the Short-Chain Fatty Acids/miR-10a-5p/PI3K-Akt Signaling Pathway.

Gut microbiota provides an important insight into clarifying the mechanism of active substances with low bioavailability, but its specific action mechanism varied case by case and remained unclear. Dihydroquercetin (DHQ) is a bioactive flavonoid with low bioavailability, which showed beneficial effects on colitis alleviation and gut microbiota modulation. Herein, we aimed to explore the microbiota-dependent anticolitis mechanism of DHQ in sight of gut microbiota metabolites and their interactions with microRNAs (miRNAs). Dietary supplementation of DHQ alleviated dextran sulfate sodium-induced colitis phenotypes and improved gut microbiota dysbiosis. Fecal microbiota transplantation further revealed that the anticolitis activity of DHQ was mediated by gut microbiota. To clarify how the modulated gut microbiota alleviated colitis in mice, the tandem analyses of the microbiome and targeted metabolome were performed, and altered profiles of metabolite short-chain fatty acids (SCFAs) and bile acids and their producers were observed in DHQ-treated mice. In addition, SCFA treatment showed anticolitis activity compared to that of bile acids, along with the specific inhibition on the phosphoinositide-3-kinase (PI3K)-protein kinase B (Akt) pathway. Subsequently, the colonic miRNA profile of mice receiving SCFA treatment was sequenced, and a differentially expressed miR-10a-5p was identified. Both prediction analysis and dual-luciferase reporter assay indicated that miR-10a-5p directly bind to the 3'-untranslated regions of gene pik3ca, inhibit the PI3K-Akt pathway activation, and lead to colitis alleviation. Together, we proposed that gut microbiota mediated the anticolitis activity of DHQ through the SCFAs/miR-10a-5p/PI3K-Akt axis, and it provided a novel insight into clarifying the microbiota-dependent mechanism via the interaction between metabolites and miRNAs.

Fecal Microbiota Transplantation Induced by Wumei Pills Improves Chemotherapy-Induced Intestinal Mucositis in BALB/c Mice by Modulating the TLR4/MyD88/NF-κB Signaling Pathway.

Our previous studies have found that Wumei Pills can regulate the intestinal flora to inhibit chemotherapy-induced intestinal mucositis (CIM). However, there is still insufficient evidence to confirm that intestinal flora is the main link in the regulation of CIM by Wumei Pills, and its downstream mechanism is still unclear. We first obtained the signal pathway of the intervention of Wumei Pill on CIM through network pharmacological analysis and then transplanted the bacterial solution into CIM mice, combined with Western Blot, HE, ELISA and other biological technology-related proteins and inflammatory factors. It showed that 97 kinds of effective ingredients and 205 kinds of targets of Wumei pills were screened out and the potential mechanism of Wumei Pills on CIM may be the NF-κB signaling pathway. In contrast with the control group, the results displayed that the weight, food intake, and mice's colon length were apparently decreased in the 5-Fu group, while the diarrhea score was increased. However, FMT reversed this change, and the difference was statistically significant. Additionally, FMT could improve the pathological state of inflammatory cell infiltration in mice, reduce histopathological scores of colon and jejunum, decrease the expression levels of IL-1β, MPO, TNF-α, and IL-6, reverse the activation of signaling pathway named TLR4/Myd88/ NF-κB and down-regulate protein expression, thereby exerting its anti-inflammatory activities. Further experiments have found that FMT could reverse the decreasing of tight junction proteins and mucins caused by 5-Fu, thereby repairing the intestinal mucosal barrier, and FMT could also increase the content of acetic acid, propanoic acid, and butanoic acid in the feces of 5-Fu group. FMT can defend the intestinal mucosal barrier integrality by increasing the content of exercise fatty acids, and its mechanism may be in connection with its inhibition of TLR4/My- D88/NF-κB signal pathway to relieve inflammation.

Impact of Clinical and Pharmacological Parameters on Faecal Microbiota Transplantation Outcome in Clostridioides difficile Infections: Results of a 5-Year French National Survey.

Detailed comparative assessment of procedure-related factors associated with faecal microbiota transplantation (FMT) efficacy in Clostridioides difficile infection (CDI) is limited. We took advantage of the differences in procedures at the various French FMT centres to determine clinical and procedure-related factors associated with FMT success in CDI. We performed a nationwide retrospective multicentre cohort study. All FMTs performed within The French Faecal Transplant Group for CDI from 2018 to 2022 were included. Clinical data were collected retrospectively from recipient medical files, characteristics of stool transplant preparations were prospectively collected by each Pharmacy involved. Univariate and multivariate analyses were performed using Fisher's test and multiple logistic regression. Six hundred fifty-eight FMTs were performed for 617 patients in 17 centres. The overall efficacy of FMT was 84.3% (520/617), with 0.5% of severe adverse events possibly related to FMT (3/658). Forty-seven patients were treated at the first recurrence of CDI with a similar success rate (85.1%). Severe chronic kidney disease (CKD; OR: 2.18, 95%CI [1.20-3.88]), non-severe refractory CDI (OR: 15.35, [1.94-318.2]), the use of ≥ 80% glycerol (OR: 2.52, [1.11-5.67]), insufficient bowel cleansing (OR: 5.47, [1.57-20.03]) and partial FMT retention (OR: 9.97, [2.62-48.49]) were associated with CDI recurrence within 8 weeks. Conditions of transplant manufacturing, bowel cleansing, and a route of delivery tailored to the patient's characteristics are key factors in optimising FMT efficacy. FMT at first recurrence showed high success in real-life practice, whereas it had lower efficacy in severe CDI and non-severe refractory CDI.

The Microbiota and Microbiome in COVID-19 in Adults and Children and Potential Therapeutic Interventions: A Review

The work presented is a comprehensive review of the role of the human microbiota in the context of the COVID-19 pandemic. A diverse microbial community heavily colonizes the human body called the microbiota, with the gut microbiota being the most diverse. The composition of the microbiota varies in different parts of the body and changes with age, diet, and other environmental factors. Emerging evidence suggests that the gut microbiota plays a critical role in modulating the host immune response and may influence the severity of COVID-19. Patients with COVID-19 have significant alterations in their gut and respiratory microbiota, characterized by a depletion of beneficial commensal bacteria and an enrichment of opportunistic pathogens. These changes in microbiota composition are associated with elevated inflammatory markers, a dysregulated immune response, and more severe disease outcomes. In addition, changes in the gut microbiota can affect lung and brain function, influencing the severity of COVID-19 cases and neurological symptoms, as well as long-term neurological complications associated with the disease. Due to the importance of the microbiota in COVID-19, several therapeutic approaches targeting the microbiota have been proposed to improve outcomes in this disease, including fecal microbiota transplantation, probiotic and prebiotic supplementation, postbiotic or microbiota-derived metabolite supplementation, dietary interventions, and lifestyle strategies. Overall, the review highlights the critical role of the human microbiota in the pathogenesis and progression of COVID-19 and the potential of microbiota-targeted interventions to improve patient outcomes. HIGHLIGHTS COVID-19 causes gut microbiota dysbiosis, associated with elevated inflammatory markers, a dysregulated immune response, and more severe disease outcomes. Gut microbiota dysbiosis due to COVID-19 affects lung and brain function, which is associated with the severity of COVID-19 cases. Gut microbiota is crucial in COVID-19, so several strategies have been developed to regulate it in COVID-19 cases, such as fecal microbiota transplantation, probiotics, and prebiotics, among others. GRAPHICAL ABSTRACT

Early-Life Milk αS1-Casein Allergy Induces the Activation of Astrocytes in Mice and Leads to Stress Vulnerability in Adulthood.

In recent years, the incidence of food allergies in children has been increasing annually, significantly affecting the quality of life for patients and their families. It has long been suspected that childhood allergies might potentially lead to behavioral and psychological issues in adulthood, but the specific connection remains unclear. In this study, we established a model of young mice allergic to milk αS1-casein, conducted behavioral tests, and employed transcriptomics, immunohistochemistry, Golgi staining, and fecal microbiota transplantation to explore the link between early life allergies and adult psychological problems. The results showed that early life milk protein allergy significantly increased intestinal epithelial permeability in mice, leading to the translocation of gut microbiota metabolites. This process subsequently activated astrocyte lysosomes via SLC15a3, making astrocytes more susceptible. This susceptibility caused mice with early life milk protein allergy to have more activated astrocytes and excessive dendritic spine phagocytosis (normal group: 5.4 ± 1.26 spines/10 μm, allergy group: 3.2 ± 0.92 spines/10 μm) under acute stress in adulthood, leading to anxiety and depressive behaviors.

The Influence of the Gut Microbiota on Host Health: A Focus on the Gut–Lung Axis and Therapeutic Approaches

The human gut microbiota is a complex ecosystem harboring thousands of microbial strains that play a crucial role in maintaining the overall well-being of its host. The composition of the gut microbiota varies with age from infancy to adulthood and is influenced by dietary habits, environment, and genetic disposition. Recent advances in culture-independent techniques and nucleic acid sequencing have improved our understanding of the diversity of the gut microbiota. The microbial species present in the gut release short-chain fatty acids (SCFAs), which have anti-inflammatory properties. The gut microbiota also plays a substantial role in modulating the host′s immune system, promoting immune tolerance, and maintaining homeostasis. The impact of the gut microbiota on the health of the host is quite evident, as gut dysbiosis has been linked to various diseases, including metabolic disorders, autoimmune diseases, allergies, and inflammatory bowel diseases. The gut microbiota has bidirectional communication with the respiratory system, creating the gut–lung axis, which has been associated with different respiratory diseases. Therapeutic approaches targeting the gut microbiota, such as probiotics, prebiotics, dietary interventions, and fecal microbiota transplantation (FMT), aim to restore microbial balance and promote the growth of beneficial strains in the gut. Nonetheless, gaining knowledge of the complex interactions between the gut microbiota and the host is necessary to develop personalized medicine approaches and microbiota-based therapies for various conditions. This review summarizes studies related to the gut–lung axis with particular emphasis on the role of the microbiota. Future research directions are also discussed.

Metagenomic, metabolomic, and lipidomic shifts associated with fecal microbiota transplantation for recurrent Clostridioides difficile infection.

Recurrent C. difficile infection (rCDI) is an urgent public health threat, for which the last resort and lifesaving treatment is a fecal microbiota transplant (FMT). However, the exact mechanisms that mediate a successful FMT are not well-understood. Here, we use longitudinal stool samples collected from patients undergoing FMT to evaluate intra-individual changes in the microbiome, metabolome, and lipidome after successful FMTs relative to their baselines pre-FMT. We show changes in the abundance of many lipids, specifically a decrease in acylcarnitines post-FMT, and a shift from conjugated bile acids pre-FMT to deconjugated secondary bile acids post-FMT. These changes correlate with a decrease in Enterobacteriaceae, which encode carnitine metabolism genes, and an increase in Lachnospiraceae, which encode bile acid altering genes such as bile salt hydrolases (BSHs) and the bile acid-inducible (bai) operon, post-FMT. We also show changes in gut microbe-encoded amino acid biosynthesis genes, of which Enterobacteriaceae was the primary contributor to amino acids C. difficile is auxotrophic for. Liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS) revealed a shift from microbial conjugation of primary bile acids pre-FMT to secondary bile acids post-FMT. Here, we define the structural and functional changes associated with a successful FMT and generate hypotheses that require further experimental validation. This information is meant to help guide the development of new microbiota-focused therapeutics to treat rCDI.IMPORTANCERecurrent C. difficile infection is an urgent public health threat, for which the last resort and lifesaving treatment is a fecal microbiota transplant. However, the exact mechanisms that mediate a successful FMT are not well-understood. Here, we show changes in the abundance of many lipids, specifically acylcarnitines and bile acids, in response to FMT. These changes correlate with Enterobacteriaceae pre-FMT, which encodes carnitine metabolism genes, and Lachnospiraceae post-FMT, which encodes bile salt hydrolases and baiA genes. There was also a shift from microbial conjugation of primary bile acids pre-FMT to secondary bile acids post-FMT. Here, we define the structural and functional changes associated with a successful FMT, which we hope will help aid in the development of new microbiota-focused therapeutics to treat rCDI.

The potential influence and intervention measures of gut microbiota on sperm: it is time to focus on testis-gut microbiota axis.

As the global male infertility rate continues to rise, there is an urgent imperative to investigate the underlying causes of sustained deterioration in sperm quality. The gut microbiota emerges as a pivotal factor in host health regulation, with mounting evidence highlighting its dual influence on semen. This review underscores the interplay between the Testis-Gut microbiota axis and its consequential effects on sperm. Potential mechanisms driving the dual impact of gut microbiota on sperm encompass immune modulation, inflammatory responses mediated by endotoxins, oxidative stress, antioxidant defenses, gut microbiota-derived metabolites, epigenetic modifications, regulatory sex hormone signaling. Interventions such as probiotics, prebiotics, synbiotics, fecal microbiota transplantation, and Traditional natural herbal extracts are hypothesized to rectify dysbiosis, offering avenues to modulate gut microbiota and enhance Spermatogenesis and motility. Future investigations should delve into elucidating the mechanisms and foundational principles governing the interaction between gut microbiota and sperm within the Testis-Gut microbiota Axis. Understanding and modulating the Testis-Gut microbiota Axis may yield novel therapeutic strategies to enhance male fertility and combat the global decline in sperm quality.

Use of frozen native feces for fecal microbiota transplantation in recurrent Clostridioides difficile infection: a simple way to improve the efficiency of donor feces preparation.

Preparing fecal microbiota transplants immediately after donation is resource-intensive, and a proportion are destroyed following abnormal screening results. We retrospectively compared two processes, frozen fecal preparation (FFP) and fresh native frozen preparation (FNFP), for clinical efficacy in the treatment of recurrent Clostridioides difficile infection (rCDI). FFP and FNFP were similarly effective with clinical success rates of 76.7% and 86.7% (P = 0.32), respectively. FNFP is an efficient procedure that saves resources while maintaining clinical efficacy in rCDI.

Peptidoglycan-Chi3l1 interaction shapes gut microbiota in intestinal mucus layer

The balanced gut microbiota in intestinal mucus layer plays an instrumental role in the health of the host. However, the mechanisms by which the host regulates microbial communities in the mucus layer remain largely unknown. Here, we discovered that the host regulates bacterial colonization in the gut mucus layer by producing a protein called Chitinase 3-like protein 1 (Chi3l1). Intestinal epithelial cells are stimulated by the gut microbiota to express Chi3l1. Once expressed, Chi3l1 is secreted into the mucus layer where it interacts with the gut microbiota, specifically through a component of bacterial cell walls called peptidoglycan. This interaction between Chi3l1 and bacteria is beneficial for the colonization of bacteria in the mucus, particularly for Gram-positive bacteria like Lactobacillus. Moreover, a deficiency of Chi3l1 leads to an imbalance in the gut microbiota, which exacerbates colitis induced by dextran sodium sulfate. By performing fecal microbiota transplantation from Villin-cre mice or replenishing Lactobacillus in IEC∆Chil1 mice, we were able to restore their colitis to the same level as that of Villin-cre mice. In summary, this study shows a ‘scaffold model’ for microbiota homeostasis by interaction between intestinal Chi3l1 and bacteria cell wall interaction, and it also highlights that an unbalanced gut microbiota in the intestinal mucus contributes to the development of colitis.

Peptidoglycan-Chi3l1 interaction shapes gut microbiota in intestinal mucus layer.

The balanced gut microbiota in intestinal mucus layer plays an instrumental role in the health of the host. However, the mechanisms by which the host regulates microbial communities in the mucus layer remain largely unknown. Here, we discovered that the host regulates bacterial colonization in the gut mucus layer by producing a protein called Chitinase 3-like protein 1 (Chi3l1). Intestinal epithelial cells are stimulated by the gut microbiota to express Chi3l1. Once expressed, Chi3l1 is secreted into the mucus layer where it interacts with the gut microbiota, specifically through a component of bacterial cell walls called peptidoglycan. This interaction between Chi3l1 and bacteria is beneficial for the colonization of bacteria in the mucus, particularly for Gram-positive bacteria like Lactobacillus. Moreover, a deficiency of Chi3l1 leads to an imbalance in the gut microbiota, which exacerbates colitis induced by dextran sodium sulfate. By performing fecal microbiota transplantation from Villin-cre mice or replenishing Lactobacillus in IEC∆Chil1 mice, we were able to restore their colitis to the same level as that of Villin-cre mice. In summary, this study shows a 'scaffold model' for microbiota homeostasis by interaction between intestinal Chi3l1 and bacteria cell wall interaction, and it also highlights that an unbalanced gut microbiota in the intestinal mucus contributes to the development of colitis.

Altered Gut Microbiome Composition in Dogs with Hyperadrenocorticism: Key Bacterial Genera Analysis

Hyperadrenocorticism (HAC) is a common endocrine disorder in dogs, which is associated with diverse metabolic abnormalities. We hypothesized that elevated cortisol levels in dogs with HAC disrupt the gut microbiome (GM), and this disruption persists even after trilostane treatment. This study explored GM composition in dogs with HAC. We included 24 dogs, 15 with HAC and 9 healthy controls, and followed up with 5 dogs with HAC who received trilostane treatment. The GM analysis revealed significant compositional changes in dogs with HAC, including reduced microbiome diversity compared to healthy controls, particularly in rare taxa, as indicated by the Shannon index (p = 0.0148). Beta diversity analysis further showed a distinct clustering of microbiomes in dogs with HAC, separating them from healthy dogs (p < 0.003). Specifically, an overrepresentation of Proteobacteria (Pseudomonadota), Actinobacteria, Bacteroides, Enterococcus, Corynebacterium, Escherichia, and Proteus populations occurred alongside a decreased Firmicutes (Bacillota) population. Despite trilostane treatment, gut dysbiosis persisted in dogs with HAC at a median of 41 d post treatment, suggesting its potential role in ongoing metabolic issues. We identified GM dysbiosis in dogs with HAC by examining key bacterial genera, offering insights into potential interventions like probiotics or fecal microbiota transplants for better HAC management.

Evaluating Bacterial Viability in Faecal Microbiota Transplantation: A Comparative Analysis of InVitro Cultivation and Membrane Integrity Methods.

Faecal microbiota transplantation (FMT) is a developing therapy for disorders related to gut dysbiosis. Despite its growing application, standardised protocols for FMT filtrate preparation and quality assessment remain undeveloped. The viability of bacteria in the filtrate is crucial for FMT's efficacy and for validating protocol execution. We compared two methods-in vitro cultivation and membrane integrity assessment-for their accuracy, reproducibility and clinical applicability in measuring bacterial viability in frozen FMT stool filtrate. Bacterial viability in stool filtrate was evaluated using (i) membrane integrity through fluorescent DNA staining with SYTO9 and propidium iodide, followed by flow cytometry and (ii) culturable bacteria counts (colony-forming units, CFU) under aerobic or anaerobic conditions. Using different types of samples (pure bacterial culture, stool of germ-free and conventionally bred mice, native and heat-treated human stool), we refined the bacterial DNA staining protocol integrated with flow cytometry for assessment of bacterial viability in frozen human stool samples. Both the membrane integrity-based and cultivation-based methods exhibited significant variability in bacterial viability across different FMT filtrates, without correlation. The cultivation-based method showed a mean coefficient of variance of 30.3%, ranging from 7.4% to 60.1%. Conversely, the membrane integrity approach yielded more reproducible results, with a mean coefficient of variance for viable cells of 6.4% ranging from 0.2% to 18.2%. Bacterial viability assessment in stool filtrate using the membrane integrity method offers robust and precise data, making it a suitable option for faecal material evaluation in FMT. In contrast, the cultivation-dependent methods produce inconsistent outcomes.

Safety and efficacy assessment of fecal microbiota transplantation as an adjunctive treatment for IgA nephropathy: an exploratory clinical trial

To assess the safety and efficacy of fecal microbiota transplantation (FMT) as an adjunctive therapeutic intervention for IgA nephropathy (IgAN). Fifteen patients with IgA nephropathy were recruited based on inclusion and exclusion criteria and underwent FMT using enteric microbial capsules. Clinical indicators, intestinal microbiota and metabolomic profiles, as well as changes in serum immune cells and cytokines, were monitored before and after FMT. No severe adverse reactions were observed in the subjects. After FMT, there was a reduction in the 24-h urinary protein quantification in subjects. The relative abundances of Phocaeicola_vulgatus, Bacteroides_uniformis, Prevotella_copri, Phocaeicola_dorei, Bacteroides_ovatus, Bacteroides_xylanisolvens, Parabacteroides _distasonis, Bifidobacterium_pseudocatenulatum, Bacteroides_sp._HF-162, and Bifidobacterium_longum changed after FMT. In terms of intestinal metabolites, the levels of acylcarnitine18:0 (ACar.18:0), cotinine, N-arachidonoyl-L-serine, phosphatidylcholine (PC. (18:3e/22:6)), serotonin, and fumagillin showed significant changes. Flow cytometry analysis showed the absolute count of plasma B cells decreased in subjects, and this change correlated with alterations in the intestinal microbiota and metabolites. This study preliminarily evaluates the safety and efficacy of FMT in patients with IgAN. No significant adverse reactions were observed, and the administration of FMT alongside ACEI/ARB therapy was effective in reducing urinary protein levels in patients with IgAN, a process that may be associated with B-cell immunity.