Effect of Fecal Microbiota Transplantation on 8-Week Remission in Patients With Ulcerative Colitis: A Randomized Clinical Trial

Xanthohumol ameliorates dextran sodium sulfate-induced colitis in mice by inhibiting of NF-κB signaling pathways and modulating intestinal microbiota

ETHNOPHARMACOLOGICAL RELEVANCE

Xanthohumol (XN), an isoprenylated flavonoid natural product found only in hops, possesses a variety of biological activities such as anticancer, anti-inflammatory, hepatoprotective, and anti-obesity.

AIM OF THE STUDY

The aim of this study was to investigate the effects and mechanisms of XN on the treatment of colitis.

MATERIALS AND METHODS

First, acute colitis was induced by using distilled water containing 3% DSS for 10 consecutive days. The therapeutic efficacy of XN was assessed by an established DSS-induced mouse colitis model. Subsequently, disease activity index (DAI) and colon length of mice were assessed. The health of the intestines was assessed by histopathological analysis. Inflammatory factors, IL-1β, IL-6, and TNF-α, were detected in colon tissues by ELISA.Finally, mouse intestinal contents were extracted and subjected to 16 S rRNA Sequencing, and the gut microbiota was analysed for Alpha-diversity and Beta-diversity.

RESULTS

The results showed that XN ameliorated DSS-induced colitis. Furthermore, XN reduced pro-inflammatory cytokine levels such as IL-1β, IL-6, and TNF-α, as well as inhibited the activation of the TLR4/NF-κB pathway, all of which helped to mitigate the inflammatory response. Finally, we also found that XN alleviated intestinal dysbiosis in colitis mice.

CONCLUSION

In conclusion, our study demonstrated that XN provides protective effects against colitis, and has the potential to be further explored as a lead compound for the treatment of inflammatory bowel disease (IBD).

Preliminary Results From a Multicenter, Randomized Trial Using Fecal Microbiota Transplantation to Induce Remission in Patients With Mild-to-Moderate Crohn's Disease

INTRODUCTION

Fecal microbiota transplantation (FMT) has shown promise at inducing remission in ulcerative colitis. This study is the first of its kind to evaluate the efficacy and safety of FMT at inducing remission in Crohn's disease (CD).

METHODS

This double-blind, placebo-controlled trial was conducted in 3 Canadian academic centers; randomized patients with mild-to-moderate CD received FMT or placebo. The first treatment was administered by colonoscopy followed by weekly oral capsules for 7 weeks. Primary end point was clinical and endoscopic remission at week 8. Secondary outcomes included clinical and endoscopic response, adverse events, and health-related quality of life using generic and disease-specific instruments.

RESULTS

From July 2017 to June 2021, 21 and 13 patients were randomized to FMT and placebo groups, respectively. The trial terminated early due to futility. At week 8, 0% (0/15) of patients in the FMT group versus 8.3% (1/11) in the placebo group reached the primary end point of combined clinical and endoscopic remission as per protocol analysis. There were no differences between the groups in clinical or endoscopic responses. One patient in each group had worsening of CD. Although both groups experienced statistically significant improvements in health-related quality of life, only the FMT group had a significant decrease in activity impairment. Although there were no significant changes in microbial diversity or composition, patients who achieved clinical response became more similar to their donors in stool microbial composition.

DISCUSSION

FMT was not effective at inducing clinical and endoscopic remission in CD using the FMT regimen in this study. Future studies may use other strategies to enhance treatment response, including longer intervention, antibiotic pretreatment, optimized donor-recipient pairing, and concomitant anti-inflammatory diet, and biologic or small molecule therapies.

Safety comparison of single-donor and pooled fecal microbiota transfer product preparation in ulcerative colitis: systematic review and meta-analysis

BACKGROUND

Multiple studies have evaluated fecal microbiota transfer (FMT) in patients with ulcerative colitis (UC) using single-donor (SDN) and multidonor (MDN) products. Systematic review and meta-analysis were performed to compare the safety of SDN and MDN products.

METHODS

Systematic searches were performed in Web of Science, Scopus, PubMed, and Orbit Intelligence to identify studies that compared FMT products manufactured using SDN or MDN strategies against control treatment in patients with UC. Fifteen controlled studies were selected for meta-analysis (11 randomized controlled trials and 4 controlled cohort trials). Safety of each treatment type was assessed using the counts of adverse events and serious adverse events using fixed- and random-effects models. Significance of the indirect difference between FMT preparations was assessed using a network approach. Benefit-risk ratios were calculated by multiplicative utility model, incorporating geometric mean of risk ratios (RRs) of efficacy and safety.

RESULTS

Safety data was collected for a total of 587 patients (193 exposed to SDN products, 114 exposed to MDN products and 280 exposed to control treatment). The 12 studies showed similar overall safety event counts for MDN and SDN versus placebo (RRs: 0.90 and 1.09, respectively [P = 0.206 and P = 0.420, respectively]). Results indicated similar risk of safety events for MDN compared to SDN (RR: 0.83, P = 0.159). Positive benefit-risk ratios were demonstrated for MDN and SDN versus placebo (RRs: 1.70 and 1.16, respectively [P = 0.003 and P = 0.173, respectively]). MDN had a greater benefit-risk ratio compared to SDN (RR: 1.46, P = 0.072).

CONCLUSION

Similar safety profiles were observed for MDN and SDN strategies. Alongside previously described superior efficacy, treatment with MDN has greater benefit-risk ratio than SDN in patients with UC. Further development of MDN FMT treatment for UC should be considered.

The Effect of Non-pooled Multidonor Faecal Microbiota Transplantation for Inducing Clinical Remission in Patients with Chronic Pouchitis: Results from a Multicentre, Randomised, Double-blinded, Placebo-controlled Trial [MicroPouch]

BACKGROUND AND AIMS

To investigate if treatment with non-pooled, multidonor faecal microbiota transplantation [FMT] for 4 weeks was superior to placebo to induce clinical remission in patients with chronic pouchitis.

METHODS

The study was a randomised, double-blinded, placebo-controlled study with a 4-week intervention period and 12-month follow-up. Eligible patients with chronic pouchitis were recruited from five Danish hospitals. Participants were randomised to non-pooled, multidonor FMT derived from four faecal donors, or placebo. Treatment was delivered daily by enema for 2 weeks, followed by every second day for 2 weeks. Disease severity was accessed at inclusion and 30-day follow-up, using the Pouchitis Disease Activity Index [PDAI]; PDAI <7 was considered equivalent to clinical remission. Faecal samples from participants and donors were analysed by shotgun metagenomic sequencing.

RESULTS

Inclusion was stopped after inclusion of 30 participants who were randomised 1:1 for treatment with FMT or placebo. There was no difference in participants achieving clinical remission between the two groups at 30-day follow-up, relative risk 1.0 (95% CI [0.55; 1.81]). Treatment with FMT resulted in a clinically relevant increase in adverse events compared with placebo, incidence rate ratio 1.67 (95% CI [1.10; 2.52]); no serious adverse events within either group. Faecal microbiota transplantation statistically significantly increased the similarity of participant faecal microbiome to the faecal donor microbiome at 30-day follow-up [p = 0.01], which was not seen after placebo.

CONCLUSIONS

Non-pooled, multidonor FMT was comparable to placebo in inducing clinical remission in patients with chronic pouchitis, but showed a clinically relevant increase in adverse events compared with placebo. ClincialTrials.gov number, NCT04100291.

Intraduodenal fecal microbiota transplantation ameliorates gut atrophy and cholestasis in a novel parenteral nutrition piglet model

Total parenteral nutrition (TPN) provides lifesaving nutritional support intravenously; however, it is associated with significant side effects. Given gut microbial alterations noted with TPN, we hypothesized that transferring fecal microbiota from healthy controls would restore gut-systemic signaling in TPN and mitigate injury. Using our novel ambulatory model (US Patent: US 63/136,165), 31 piglets were randomly allocated to enteral nutrition (EN), TPN only, TPN + antibiotics (TPN-A), or TPN + intraduodenal fecal microbiota transplant (TPN + FMT) for 14 days. Gut, liver, and serum were assessed through histology, biochemistry, and qPCR. Stool samples underwent 16 s rRNA sequencing. Permutational multivariate analysis of variance, Jaccard, and Bray-Curtis metrics were performed. Significant bilirubin elevation in TPN and TPN-A versus EN (P < 0.0001) was prevented with FMT. IFN-G, TNF-α, IL-β, IL-8, and lipopolysaccharide (LPS) were significantly higher in TPN (P = 0.009, P = 0.001, P = 0.043, P = 0.011, P < 0.0001), with preservation upon FMT. Significant gut atrophy by villous-to-crypt ratio in TPN (P < 0.0001) and TPN-A (P = 0.0001) versus EN was prevented by FMT (P = 0.426 vs. EN). Microbiota profiles using principal coordinate analysis demonstrated significant FMT and EN overlap, with the largest separation in TPN-A followed by TPN, driven primarily by Firmicutes and Fusobacteria. TPN-altered gut barrier was preserved upon FMT; upregulated cholesterol 7 α-hydroxylase and bile salt export pump in TPN and TPN-A and downregulated fibroblast growth factor receptor 4, EGF, farnesoid X receptor, and Takeda G Protein-coupled Receptor 5 (TGR5) versus EN was prevented by FMT. This study provides novel evidence of prevention of gut atrophy, liver injury, and microbial dysbiosis with intraduodenal FMT, challenging current paradigms into TPN injury mechanisms and underscores the importance of gut microbes as prime targets for therapeutics and drug discovery.NEW & NOTEWORTHY Intraduodenal fecal microbiota transplantation presents a novel strategy to mitigate complications associated with total parenteral nutrition (TPN), highlighting gut microbiota as a prime target for therapeutic and diagnostic approaches. These results from a highly translatable model provide hope for TPN side effect mitigation for thousands of chronically TPN-dependent patients.

Washed microbiota transplantation combined with biological agents promotes histological remission in refractory severe ulcerative colitis with recurrent intestinal infection: A case report

Ulcerative colitis (UC) is a chronic non-specific colitis disease. In recent years, fecal microbiota transplantation (FMT), including improved washed microbiota transplantation (WMT), and biological agents have helped improve the prognosis of patients with UC. However, a significant number of patients with moderate to severe UC do not get relief from glucocorticoids, immunosuppressants, and TNF-α antagonists. Patients with severe UC are frequently burdened with opportunistic infections and subsequent surgical interventions. Combined treatment modalities are crucial for patients with severe UC and opportunistic infections. Herein, we reported a case of a 25-year-old female with refractory severe UC complicated with recurrent Clostridioides difficile infection and recurrent cytomegalovirus infection for six years. Surgical removal of the affected bowel segment was almost unavoidable. She showed endoscopic and histological recovery after comprehensive WMT and Vedolizumab treatment. The following are our learnings from the case: 1. A combination of WMT and biological agents can potentially obviate the necessity for surgical treatment in patients with refractory severe UC and promote histological remission. 2. Personalized comprehensive treatment and chronic disease management models for patients with UC should be emphasized. 3. WMT can help treat opportunistic infections, which may also strengthen the treatment with gut-targeted biological agents when traditional TNF-α antagonists show poor efficacy.

The role of the fecal microbiota in inflammatory bowel disease

The understanding of the potential role of the microbiota in the pathogenesis of inflammatory bowel disease (IBD) is ever-evolving. Traditionally, the management of IBD has involved medical therapy and/or surgical intervention. IBD can be characterized by gut microbiome alterations through various pathological processes. Various studies delve into nontraditional methods such as probiotics and fecal microbiota transplant and their potential therapeutic effects. Fecal microbiota transplant involves the delivery of a balanced composition of gut microorganisms into an affected patient via multiple possible routes and methods, while probiotics consist of live microorganisms given via the oral route. At present, neither method is considered first-line treatment, however, fecal microbiota transplant has shown potential success in inducing and maintaining remission in ulcerative colitis. In a study by Kruis and colleagues, Escherichia coli Nissle 1917 was considered to be equivalent to mesalamine in mild ulcerative colitis. Alteration of the microbiome in the management of Crohn's disease is less well defined. Furthermore, variation in the clinical usefulness of 5-aminosalicylic acid medication has been attributed, in part, to its acetylation and inactivation by gut microbes. In summary, our understanding of the microbiome's role is continually advancing, with the possibility of paving the way for personalized medicine based on the microbiome.

Washed microbiota transplantation improved the level of serum vitamin D in ulcerative colitis

BACKGROUND AND AIM

Vitamin D (VD) deficiency was reported to correlate with ulcerative colitis (UC) activity, which might be closely related to gut microbiota dysbiosis. This study aims to investigate the effects of washed microbiota transplantation (WMT) on VD metabolism in UC.

METHODS

The serum levels of 25-hdroxyvitamin D [25(OH)D] in 121 patients with UC and 53 healthy controls (HC) were detected. Subsequently, a non-randomized control trial (non-RCT) was conducted. Patients with UC were non-randomly assigned to undergo WMT (n = 28) vs. conventional treatment (5-aminosalicylic acid, 5-ASA, n = 10). Serum levels of 25(OH)D, fecal microbiota, and the expression of vitamin D receptor (VDR) in patients with UC were evaluated with a 3-month follow-up.

RESULTS

Serum VD levels collected in the clinic practice indicated that patients with UC had significantly lower VD levels than HC (P < 0.001). In the non-RCT, serum 25(OH)D level and VDR expression significantly increased (P = 0.011, 0.026, respectively) in the WMT group, while no noticeable changes were observed in the non-WMT group. Microbiome profiling revealed that the increase in VD levels after WMT was positively associated with the abundances of Adlercreutzia_equolifaciens, Ruminococcus_obeum, and Dorea but negatively correlated with Escherichia.

CONCLUSIONS

The study suggested that WMT increases the levels of VD with characteristic changes of specific microbiota, which indicated the association between the VD and the activity of UC might be regulated by gut microbiota.

Alteration in the Gut Microbiota of Chickens Resistant to Eimeria tenella Infection

Avian coccidiosis, caused by several species of Eimeria, is a widespread and economically important poultry disease that inflicts severe losses in the poultry industry. Understanding the interplay between Eimeria and gut microbiota is critical for controlling coccidiosis and developing innovative treatments to ensure good poultry health. In the present study, chickens were immunized six times with a low dose of Eimeria tenella, resulting in complete immunity against Eimeria infection. The results of fecal microbiota transplantation showed that the gut microbiota of immunized chickens induced a certain degree of resistance to coccidial infection. To investigate the types of intestinal microbiota involved in the development of resistance to Eimeria, the intestinal contents and fecal samples from both immunized and unimmunized groups were collected for 16S rRNA gene sequencing. The results showed that, at the genus level, the abundance of the Eubacterium coprostanoligenes group, Erysipelatoclostridium, Shuttleworthia, and Colidextribacter was significantly increased in the intestinal content of immunized chickens, whereas the abundance of Eisenbergiella was significantly decreased. In fecal samples, the abundance of Clostridiaceae and Muribaculaceae significantly increased, whereas that of Bacillales significantly decreased. These findings will help to elucidate the interactions between E. tenella and the gut microbiota of chickens, providing a basis for isolating E. tenella-resistant strains from the gut microbiome and developing new vaccines against coccidiosis.

The landscape of new therapeutic opportunities for IBD

This chapter presents an overview of the emerging strategies to address the unmet needs in the management of inflammatory bowel diseases (IBD). IBD poses significant challenges, as over half of patients experience disease progression despite interventions, leading to irreversible complications, and a substantial proportion do not respond to existing therapies, such as biologics. To overcome these limitations, we describe a diverse array of novel therapeutic approaches. In the area of immune homeostasis restoration, the focus is on targeting cytokine networks, leukocyte trafficking, novel immune pathways, and cell therapies involving regulatory T cells and mesenchymal stem cells (MSC). Recognizing the critical role of impaired intestinal barrier integrity in IBD, we highlight therapies aimed at restoring barrier function and promoting mucosal healing, such as those targeting cell proliferation, tight junctions, and lipid mediators. Addressing the challenges posed by fibrosis and fistulas, we describe emerging targets for reversing fibrosis like kinase and cytokine inhibitors and nuclear receptor agonists, as well as the potential of MSC for fistulas. The restoration of a healthy gut microbiome, through strategies like fecal microbiota transplantation, rationally defined bacterial consortia, and targeted antimicrobials, is also highlighted. We also describe innovative approaches to gut-targeted drug delivery to enhance efficacy and minimize side effects. Reinforcing these advancements is the critical role of precision medicine, which emphasizes the use of multiomics analysis for the discovery of biomarkers to enable personalized IBD care. Overall, the emerging landscape of therapeutic opportunities for IBD holds great potential to surpass the therapeutic ceiling of current treatments.

Host-pathobiont interactions in Crohn's disease

The mammalian intestine is colonized by trillions of microorganisms that are collectively referred to as the gut microbiota. The majority of symbionts have co-evolved with their host in a mutualistic relationship that benefits both. Under certain conditions, such as in Crohn's disease, a subtype of inflammatory bowel disease, some symbionts bloom to cause disease in genetically susceptible hosts. Although the identity and function of disease-causing microorganisms or pathobionts in Crohn's disease remain largely unknown, mounting evidence from animal models suggests that pathobionts triggering Crohn's disease-like colitis inhabit certain niches and penetrate the intestinal tissue to trigger inflammation. In this Review, we discuss the distinct niches occupied by intestinal symbionts and the evidence that pathobionts triggering Crohn's disease live in the mucus layer or near the intestinal epithelium. We also discuss how Crohn's disease-associated mutations in the host disrupt intestinal homeostasis by promoting the penetration and accumulation of pathobionts in the intestinal tissue. Finally, we discuss the potential role of microbiome-based interventions in precision therapeutic strategies for the treatment of Crohn's disease.

Safety and efficacy of fecal microbiota transplantation for viral diseases: A systematic review of clinical trials

BACKGROUND

Gut microbiota play important roles in several diseases like viral infections. In this systematic review, our objective was to assess the efficacy and safety of fecal microbiota transplantation (FMT) in treating various viral diseases.

METHODS

We conducted searches on databases including PubMed, Web of Science, Scopus, and Google Scholar until November 2023. Clinical trials reported outcomes related to safety of FMT or its efficacy in patients with viral diseases were included. We excluded other types of studies that enrolled healthy individuals or patients with other disorders and did not use FMT. The assessment of bias risk was conducted using the National Institutes of Health (NIH) study quality evaluation tool.

RESULTS

Eight studies with total 196 participants were included. Viral diseases were human immunodeficiency virus (HIV), hepatitis B, COVID-19 and Clostridioides difficile coinfection, and cytomegalovirus colitis. In hepatitis B cases, HBeAg clearance was significant in those received FMT (p<0.01), while it was not significant in another one (p = 0.19). A clinical response was noted in 37.5% of patients with cytomegalovirus colitis, with an equal percentage achieving clinical remission post-FMT. There was a significant reduction in Clostridioides difficile relapse rate in FMT group than controls in coinfection of Clostridioides difficile and COVID-19 (2.17% vs. 42.5%, p<0.05). In patients with HIV, partial engraftment of the donor microbiome and increases in alpha diversity were observed after FMT. No severe adverse events were reported. Most studies had fair or good qualities.

CONCLUSIONS

Our findings revealed FMT as a promising, safe treatment for some viral diseases. It improved viral clearance, clinical outcomes, and inflammation. However, the varying responses and small sample sizes call for more trials on FMT in viral diseases.

Gut Microbiota Features in Relation to Fecal Microbiota Transplantation Outcome in Ulcerative Colitis: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Fecal microbiota transplantation (FMT) can induce remission in patients with ulcerative colitis, yet its efficacy needs improvement. We conducted a comprehensive evaluation of the current literature on microbial factors affecting outcome, as well as a meta-analysis on some of the largest datasets regarding composition.

METHODS

MEDLINE, Embase, and Cochrane were systematically searched through August 2024 for relevant studies. The quality of studies was analyzed with JBI tools and a composite critical appraisal score. Additionally, species-level data from 2 landmark FMT trials (the Transplantation of Feces in Ulcerative Colitis; Returning Nature's Homeostasis [TURN] and Fecal Microbiota Transplantation for Chronic Active Ulcerative Colitis [FOCUS] trials) were reanalyzed from a compositional perspective.

RESULTS

Out of 3755 citations identified, 56 met the inclusion criteria, of which 29 fulfilled quality standards. Higher microbial α-diversity, either in donors or recipients (at baseline or following FMT treatment), was associated with better clinical response rates. Engraftment of the donors' microbiota could not be clearly linked with clinical response, possibly because not every donor has an ideal microbiome. Butyrate-producing species from the Lachnospiraceae and Oscillospiraceae families were often related with response, whereas the reverse was true for Fusobacteria, many Proteobacteria, and Ruminococcus gnavus. Compositional analyses showed that clinical response is associated with a shift from a low-diversity, often Bacteroides-dominant composition to one with higher diversity, either dominated by various butyrate producers, the Christensenellaceae-Methanobrevibacter trophic network, or a moderate/high-diversity composition with abundant but not excessive levels of Prevotella copri.

CONCLUSIONS

This systematic review/meta-analysis yielded a coherent picture from a compositional perspective, which may help identify beneficial donor profiles and guide personalized FMT approaches.

The Gut Microbiome Advances Precision Medicine and Diagnostics for Inflammatory Bowel Diseases

The gut microbiome emerges as an integral component of precision medicine because of its signature variability among individuals and its plasticity, which enables personalized therapeutic interventions, especially when integrated with other multiomics data. This promise is further fueled by advances in next-generation sequencing and metabolomics, which allow in-depth high-precision profiling of microbiome communities, their genetic contents, and secreted chemistry. This knowledge has advanced our understanding of our microbial partners, their interaction with cellular targets, and their implication in human conditions such as inflammatory bowel disease (IBD). This explosion of microbiome data inspired the development of next-generation therapeutics for treating IBD that depend on manipulating the gut microbiome by diet modulation or using live products as therapeutics. The current landscape of artificial microbiome therapeutics is not limited to probiotics and fecal transplants but has expanded to include community consortia, engineered probiotics, and defined metabolites, bypassing several limitations that hindered rapid progress in this field such as safety and regulatory issues. More integrated research will reveal new therapeutic targets such as enzymes or receptors mediating interactions between microbiota-secreted molecules that drive or modulate diseases. With the shift toward precision medicine and the enhanced integration of host genetics and polymorphism in treatment regimes, the following key questions emerge: How can we effectively implement microbiomics to further personalize the treatment of diseases like IBD, leveraging proven and validated microbiome links? Can we modulate the microbiome to manage IBD by altering the host immune response? In this review, we discuss recent advances in understanding the mechanism underpinning the role of gut microbes in driving or preventing IBD. We highlight developed targeted approaches to reverse dysbiosis through precision editing of the microbiome. We analyze limitations and opportunities while defining the specific clinical niche for this innovative therapeutic modality for the treatment, prevention, and diagnosis of IBD and its potential implication in precision medicine.

Ulcerative colitis: molecular insights and intervention therapy

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by abdominal pain, diarrhea, rectal bleeding, and weight loss. The pathogenesis and treatment of UC remain key areas of research interest. Various factors, including genetic predisposition, immune dysregulation, and alterations in the gut microbiota, are believed to contribute to the pathogenesis of UC. Current treatments for UC include 5-aminosalicylic acids, corticosteroids, immunosuppressants, and biologics. However, study reported that the one-year clinical remission rate is only around 40%. It is necessary to prompt the exploration of new treatment modalities. Biologic therapies, such as anti-TNF-α monoclonal antibody and JAK inhibitor, primarily consist of small molecules targeting specific pathways, effectively inducing and maintaining remission. Given the significant role of the gut microbiota, research into intestinal microecologics, such as probiotics and prebiotics, and fecal microbiota transplantation (FMT) shows promising potential in UC treatment. Additionally, medicinal herbs, such as chili pepper and turmeric, used in complementary therapy have shown promising results in UC management. This article reviews recent findings on the mechanisms of UC, including genetic susceptibility, immune cell dynamics and cytokine regulation, and gut microbiota alterations. It also discusses current applications of biologic therapy, herbal therapy, microecologics, and FMT, along with their prospects and challenges.

Management of ulcerative colitis: where are we at and where are we heading?

INTRODUCTION

Remission rates for ulcerative colitis (UC) remain low despite significant progress in disease understanding and the introduction of novel therapeutic agents. Several challenges contribute to this, including the heterogeneity of the disease, suboptimal efficacy of current diagnostic and therapeutic tools, drug safety concerns, and limited access to newer treatment options.

AREAS COVERED

This review evaluates current treatment targets in UC, assessing the effectiveness of various therapies and management strategies in achieving remission. We explore the potential role of personalized medicine, which tailors treatment based on clinical predictors, genetic factors, and immunologic profiles. Personalized approaches show promise in improving remission rates by addressing the unique characteristics of each patient. We also discussed the feasibility of adapting such management models and suggested solutions to some of the challenges in their implementation.

EXPERT OPINION

Future efforts should prioritize the continued development of biologics, small molecules, and digital health solutions, alongside noninvasive monitoring techniques. These innovations could not only enhance patient outcomes by improving remission rates but also reduce healthcare costs by minimizing hospitalization and surgical interventions. Ultimately, a personalized, stratified approach to UC management is key to optimizing patient care and addressing the unmet needs in this field.

Recent advances in bacteria-based platforms for inflammatory bowel diseases treatment

Inflammatory bowel disease (IBD) is a recurring chronic inflammatory disease. Current treatment strategies are aimed at alleviating clinical symptoms and are associated with gastrointestinal or systemic adverse effects. New delivery strategies are needed for the treatment of IBD. Bacteria are promising biocarriers, which can produce drugs in situ and sense the gut in real time. Herein, we focus on recent studies of engineered bacteria used for IBD treatment and introduce the application of engineered bacteria in the diagnosis. On this basis, the current dilemmas and future developments of bacterial delivery systems are discussed.

Goblet cells: guardians of gut immunity and their role in gastrointestinal diseases

Goblet cells (GCs) are specialised guardians lining the intestine. They play a critical role in gut defence and immune regulation. GCs continuously secrete mucus creating a physical barrier to protect from pathogens while harbouring symbiotic gut bacteria adapted to live within the mucus. GCs also form specialised GC-associated passages in a dynamic and regulated manner to deliver luminal antigens to immune cells, promoting gut tolerance and preventing inflammation. The composition of gut bacteria directly influences GC function, highlighting the intricate interplay between these components of a healthy gut. Indeed, imbalances in the gut microbiome can disrupt GC function, contributing to various gastrointestinal diseases like colorectal cancer, inflammatory bowel disease, cystic fibrosis, pathogen infections and liver diseases. This review explores the interplay between GCs and the immune system. We delve into the underlying mechanisms by which GC dysfunction contributes to the development and progression of gastrointestinal diseases. Finally, we examine current and potential treatments that target GCs and represent promising avenues for further investigation.

Analysis of metagenome and metabolome disclosed the mechanisms of Dendrobium officinale polysaccharide on DSS-induced ulcerative colitis-affected mice

Currently, there is no known cause for ulcerative colitis (UC), an inflammatory bowel disease that is difficult to treat. This assay aimed to investigate the protective effects and mechanisms of Dendrobium officinale polysaccharide (DOP) in mice with acute UC induced by dextran sulphate sodium (DSS). We found that DOP could improve weight loss, decrease the disease activity index (DAI), and regulate the release of interleukin 2 (IL-2), IL-4, IL-6, and IL-10 in DSS-induced acute UC mice. Additionally, DOP preserved the integrity of the intestinal barrier in UC mice by increasing goblet cell density and maintaining tight junctions. DOP significantly enhanced total antioxidant capacity (T-AOC), and reduced glutathione (GSH), nitric oxide (NO), and malondialdehyde (MDA) levels in the bloodstream. In terms of serum biochemistry, DOP markedly elevated levels of bilirubin (BIL), alkaline phosphatase (ALP), total bile acid (TBA), creatinine (Crea), and creative kinase isoenzyme (CKMB). Furthermore, DOP increased the relative abundance of Lactobacillales. DOP also improved intestinal health and stimulated the synthesis of potent anti-inflammatory and antiviral substances by regulating the metabolism of purines, prostaglandins, and leukotrienes. Therefore, DOP can be considered a functional dietary supplement for the treatment of UC, as it improves the condition of DSS-induced UC mice.

Role of microbiome in autoimmune liver diseases

The microbiome plays a crucial role in integrating environmental influences into host physiology, potentially linking it to autoimmune liver diseases, such as autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. All autoimmune liver diseases are associated with reduced diversity of the gut microbiome and altered abundance of certain bacteria. However, the relationship between the microbiome and liver diseases is bidirectional and varies over the course of the disease. This makes it challenging to dissect whether such changes in the microbiome are initiating or driving factors in autoimmune liver diseases, secondary consequences of disease and/or pharmacological intervention, or alterations that modify the clinical course that patients experience. Potential mechanisms include the presence of pathobionts, disease-modifying microbial metabolites, and more nonspecific reduced gut barrier function, and it is highly likely that the effect of these change during the progression of the disease. Recurrent disease after liver transplantation is a major clinical challenge and a common denominator in these conditions, which could also represent a window to disease mechanisms of the gut-liver axis. Herein, we propose future research priorities, which should involve clinical trials, extensive molecular phenotyping at high resolution, and experimental studies in model systems. Overall, autoimmune liver diseases are characterized by an altered microbiome, and interventions targeting these changes hold promise for improving clinical care based on the emerging field of microbiota medicine.

Characteristics of Mucosa-Associated Microbiota in Ulcerative Colitis Patients with 5-Aminosalicylic Acid Intolerance

BACKGROUND/OBJECTIVES

5-Aminosalicylic acid (5-ASA) is a first-line therapy for ulcerative colitis (UC). This study examined the mucosa-associated microbiota (MAM) in UC patients, distinguishing between those who were 5-ASA tolerant and intolerant.

METHODS

Brushing samples were collected from the sigmoid and ileal end of patients with UC during endoscopic procedures. The samples were profiled by using the Illumina MiSeq platform. The V3-V4 regions of the 16S rRNA gene (460 bp) were amplified by using tailed PCR.

RESULTS

A total of 15 patients with 5-ASA intolerance, 38 patients with 5-ASA tolerance, and 19 healthy controls were recruited in this study. The α-diversity indices were remarkably different among the three groups in the ileum mucosa but not in the sigmoid colon. In the ileum mucosa, Alistipes, Ruminococcaceae, and Odoribacter were less abundant in the 5-ASA-intolerant group than in the control and 5-ASA-tolerant groups. On the contrary, Merdibacter, Brevundimonas, and Porphyromonas were more abundant in the 5-ASA-intolerant group than in other groups.

CONCLUSIONS

The present study showed that the changes in MAM were characterized by a decrease in mucoprotective bacteria rather than an increase in harmful bacteria.

Cultured fecal microbial community and its impact as fecal microbiota transplantation treatment in mice gut inflammation

The fecal microbiome is identical to the gut microbial communities and provides an easy access to the gut microbiome. Therefore, fecal microbial transplantation (FMT) strategies have been used to alter dysbiotic gut microbiomes with healthy fecal microbiota, successfully alleviating various metabolic disorders, such as obesity, type 2 diabetes, and inflammatory bowel disease (IBD). However, the success of FMT treatment is donor-dependent and variations in gut microbes cannot be avoided. This problem may be overcome by using a cultured fecal microbiome. In this study, a human fecal microbiome was cultured using five different media; growth in brain heart infusion (BHI) media resulted in the highest microbial community cell count. The microbiome (16S rRNA) data demonstrated that the cultured microbial communities were similar to that of the original fecal sample. Therefore, the BHI-cultured fecal microbiome was selected for cultured FMT (cFMT). Furthermore, a dextran sodium sulfate (DSS)-induced mice-IBD model was used to confirm the impact of cFMT. Results showed that cFMT effectively alleviated IBD-associated symptoms, including improved gut permeability, restoration of the inflamed gut epithelium, decreased expression of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-1, IL-6, IL-12, and IL-17), and increased expression of anti-inflammatory cytokines (IL-4 and IL-10). Thus, study's findings suggest that cFMT can be a potential alternative to nFMT. KEY POINTS: • In vitro fecal microbial communities were grown in a batch culture using five different media. • Fecal microbial transplantation was performed on DSS-treated mice using cultured and normal fecal microbes. • Cultured fecal microbes effectively alleviated IBD-associated symptoms.

l-Theanine Alleviates Ulcerative Colitis by Regulating Colon Immunity via the Gut Microbiota in an MHC-II-Dependent Manner

Alterations to the gut microbiota are associated with ulcerative colitis (UC), whereas restoration of normobiosis can effectively alleviate UC. l-Theanine has been shown to reshape the gut microbiota and regulate gut immunity. To investigate the mechanisms by which l-theanine alleviates UC, we used l-theanine and l-theanine fecal microbiota solution to treat UC mice. In this study, we used l-theanine and l-theanine fecal microbiota solution to treat UC mice to explore the mechanism by which l-theanine alleviates UC. By reducing inflammation in the colon, we demonstrated that l-theanine alleviates symptoms of UC. Meanwhile, l-theanine can improve the abundance of microbiota related to short-chain fatty acid, bile acid, and tryptophan production. Single-cell sequencing results indicated that l-theanine-mediated suppression of UC was associated with immune cell changes, especially regarding macrophages and T and B cells, and validated the immune cell responses to the gut microbiota. Further, flow cytometry results showed that the ability of dendritic cells, macrophages, and monocytes to present microbiota antigens to colonic T cells in an MHC-II-dependent manner was reduced after treating normal mouse fecal donors with l-theanine. These results demonstrate that l-theanine modulates colon adaptive and innate immunity by regulating the gut microbiota in an MHC-II-dependent manner, thereby alleviating UC.

Perception of fecal microbiota transplantation in patients with ulcerative colitis in Korea: a KASID multicenter study

BACKGROUND/AIMS

Fecal microbiota transplantation (FMT) is a promising therapy for inducing and maintaining remission in patients with ulcerative colitis (UC). However, FMT has not been approved for UC treatment in Korea. Our study aimed to investigate patient perceptions of FMT under the national medical policy.

METHODS

This was a prospective, multicenter study. Patients with UC ≥ 19 years of age were included. Patients were surveyed using 22 questions on FMT. Changes in perceptions of FMT before and after education were also compared.

RESULTS

A total of 210 patients with UC were enrolled. We found that 51.4% of the patients were unaware that FMT was an alternative treatment option for UC. After reading the educational materials on FMT, more patients were willing to undergo this procedure (27.1% vs. 46.7%; p < 0.001). The preferred fecal donor was the one recommended by a physician (41.0%), and the preferred transplantation method was the oral capsule (30.4%). A large proportion of patients (50.0%) reported that the national medical policy influenced their choice of FMT treatment. When patients felt severe disease activity, their willingness to undergo FMT increased (92.3% vs. 43.1%; p = 0.001).

CONCLUSION

Education can increase preference for FMT in patients with UC. When patients have severe disease symptoms or their quality of life decreases their willingness to undergo FMT increases. Moreover, national medical policies may influence patient choices regarding FMT.

Perspectives on the involvement of the gut microbiota in salt-sensitive hypertension

Salt-sensitivity hypertension (SSH) is an independent predictor of cardiovascular event-related death. Despite the extensiveness of research on hypertension, which covers areas such as the sympathetic nervous system, the renin-angiotensin system, the vascular system, and the immune system, its pathogenesis remains elusive, with sub-optimal blood pressure control in patients. The gut microbiota is an important component of nutritional support and constitutes a barrier in the host. Long-term high salt intake can lead to gut microbiota dysbiosis and cause significant changes in the expression of gut microbiota-related metabolites. Of these metabolites, short chain fatty acids (SCFAs), trimethylamine oxide, amino acids, bile acids, and lipopolysaccharide are essential mediators of microbe-host crosstalk. These metabolites may contribute to the incidence and development of SSH via inflammatory, immune, vascular, and nervous pathways, among others. In addition, recent studies, including those on the histone deacetylase inhibitory mechanism of SCFAs and the blood pressure-decreasing effects of H2S via vascular activation, suggest that several proteins and factors in the classical pathway elicit their effects through multiple non-classical pathways. This review summarizes changes in the gut microbiota and its related metabolites in high-salt environments, as well as corresponding treatment methods for SSH, such as diet management, probiotic and prebiotic use, antibiotic use, and fecal transplantation, to provide new insights and perspectives for understanding SSH pathogenesis and the development of strategies for its treatment.

Transformation of colitis and colorectal cancer: a tale of gut microbiota

Intestinal inflammation modifies host physiology to promote the occurrence of colorectal cancer (CRC), as seen in colitis-associated CRC. Gut microbiota is crucial in cancer progression, primarily by inducing intestinal chronic inflammatory microenvironment, leading to DNA damage, chromosomal mutation, and alterations in specific metabolite production. Therefore, there is an increasing interest in microbiota-based prevention and treatment strategies, such as probiotics, prebiotics, microbiota-derived metabolites, and fecal microbiota transplantation. This review aims to provide valuable insights into the potential correlations between gut microbiota and colitis-associated CRC, as well as the promising microbiota-based strategies for colitis-associated CRC.

Faecal microbiota transplantation in children: A systematic review

AIM

Novel technologies offer insights into the potential role of the intestinal microbiota in human health and disease. Dysbiosis has been associated with several diseases, and it is thought to play a role in the pathogenesis of different gastrointestinal diseases. Faecal microbiota transplantation (FMT) is emerging as a method to modulate the gastrointestinal microbial ecosystem. While recurrent Clostridioides difficile infection is the recognised FMT indication, exploration of other therapeutic uses is ongoing.

METHODS

Following PRISMA guidelines, we conducted a systematic review, extracting 583 articles from Embase and PubMed (index date to October 2022).

RESULTS

The search yielded 58 studies for full review, with 50 included in the systematic review. Articles were categorised by FMT indication, study design, efficacy, adverse events, donor selection and administration route. FMT appears safe and effective for recurrent Clostridioides difficile infection, although severe adverse events are reported in children. However, there are currently insufficient data to support the use of FMT for other potential therapeutic indications (such as irritable or inflammatory bowel disease or obesity), beside the potential to decolonise multi-drug resistant organisms.

CONCLUSION

This underscores the need for randomised, controlled, prospective cohort studies in children to assess FMT effectiveness in diverse conditions and counteract publication bias.

Gut microbiota in inflammation and colorectal cancer: A potential Toolbox for Clinicians

Colorectal cancer (CRC) is a worldwide public health issue specifically in patients with chronic diseases associated with a western lifestyle, such as metabolic diseases and inflammatory bowel diseases (IBD). Interestingly, both metabolic disorders and IBD are characterized by a chronic state of inflammation that contributes to the carcinogenesis with specific alteration of the gut microbiota composition and function. Evidence now shows that this altered gut microbiota contributes fueling a chronic pro-inflammatory state in a vicious circle that can favor CRC development. In this review article, we present the current knowledge concerning the involvement of the gut microbiota as a procarcinogenic factor shared by IBD and cardiometabolic diseases, and provide clues as to how it may be used to prevent or diagnose CRC.

Causal role of the gut microbiome in certain human diseases: a narrative review

Composed of an elaborate ecosystem of bacteria, fungi, viruses and protozoa residing in the human digestive tract, the gut microbiome influences metabolism, immune modulation, bile acid homeostasis and host defence. Through observational and preclinical data, the gut microbiome has been implicated in the pathogenesis of a spectrum of chronic diseases ranging from psychiatric to gastrointestinal in nature. Until recently, the lack of unequivocal evidence supporting a causal link between gut microbiome and human health outcomes incited controversy regarding its significance. However, recent randomised controlled trial (RCT) evidence in conditions, such as Clostridioides difficile infection, cancer immunotherapy and ulcerative colitis, has supported a causal relationship and has underscored the potential of the microbiome as a therapeutic target. This review delineates the RCT evidence substantiating the potential for a causal relationship between the gut microbiome and human health outcomes, the seminal observational evidence that preceded these RCTs and the remaining knowledge gaps.

Gut microbiota dysbiosis and its impact on asthma and other lung diseases: potential therapeutic approaches

The emerging field of gut-lung axis research has revealed a complex interplay between the gut microbiota and respiratory health, particularly in asthma. This review comprehensively explored the intricate relationship between these two systems, focusing on their influence on immune responses, inflammation, and the pathogenesis of respiratory diseases. Recent studies have demonstrated that gut microbiota dysbiosis can contribute to asthma onset and exacerbation, prompting investigations into therapeutic strategies to correct this imbalance. Probiotics and prebiotics, known for their ability to modulate gut microbial compositions, were discussed as potential interventions to restore immune homeostasis. The impact of antibiotics and metabolites, including short-chain fatty acids produced by the gut microbiota, on immune regulation was examined. Fecal microbiota transplantation has shown promise in various diseases, but its role in respiratory disorders is not established. Innovative approaches, including mucus transplants, inhaled probiotics, and microencapsulation strategies, have been proposed as novel therapeutic avenues. Despite challenges, including the sophisticated adaptability of microbial communities and the need for mechanistic clarity, the potential for microbiota-based interventions is considerable. Collaboration between researchers, clinicians, and other experts is essential to unravel the complexities of the gut-lung axis, paving a way for innovative strategies that could transform the management of respiratory diseases.

BCAA mediated microbiota-liver-heart crosstalk regulates diabetic cardiomyopathy via FGF21

BACKGROUND

Diabetic cardiomyopathy (DCM) is one of leading causes of diabetes-associated mortality. The gut microbiota-derived branched-chain amino acids (BCAA) have been reported to play a central role in the onset and progression of DCM, but the potential mechanisms remain elusive.

RESULTS

We found the type 1 diabetes (T1D) mice had higher circulating BCAA levels due to a reduced BCAA degradation ability of the gut microbiota. Excess BCAA decreased hepatic FGF21 production by inhibiting PPARα signaling pathway and thereby resulted in a higher expression level of cardiac LAT1 via transcription factor Zbtb7c. High cardiac LAT1 increased the levels of BCAA in the heart and then caused mitochondrial damage and myocardial apoptosis through mTOR signaling pathway, leading to cardiac fibrosis and dysfunction in T1D mice. Additionally, transplant of faecal microbiota from healthy mice alleviated cardiac dysfunction in T1D mice, but this effect was abolished by FGF21 knockdown.

CONCLUSIONS

Our study sheds light on BCAA-mediated crosstalk among the gut microbiota, liver and heart to promote DCM and FGF21 serves as a key mediator. Video Abstract.

The Role of Fecal Microbiota Transplantation (FMT) in the Management of Metabolic Diseases in Humans: A Narrative Review

The gut microbiota represents a complex ecosystem of trillions of microorganisms residing in the human gastrointestinal tract, which is known to interact with the host physiology and regulate multiple functions. Alterations in gut microbial composition, diversity, and function are referred to as dysbiosis. Dysbiosis has been associated with a variety of chronic diseases, including Clostridioides difficile infections, but also cardiometabolic diseases, including obesity, metabolic syndrome, and type 2 diabetes mellitus (T2DM). The implication of gut microbiota dysbiosis in the pathogenesis of both obesity and T2DM has paved the way to implementing novel therapeutic approaches for metabolic diseases through gut microbial reconfiguration. These interventions include probiotics, prebiotics, and synbiotics, while a more innovative approach has been fecal microbiota transplantation (FMT). FMT is a procedure that delivers healthy human donor stool to another individual through the gastrointestinal tract, aiming to restore gut microbiota balance. Several studies have investigated this approach as a potential tool to mitigate the adverse metabolic effects of gut microbiota aberrations associated with obesity and T2DM. The aim of the present review was to critically summarize the existing evidence regarding the clinical applications of FMT in the management of obesity and T2DM and provide an update on the potential of this method to remodel the entire host microbiota, leading thus to weight loss and sustained metabolic benefits. Safety issues, long-term efficacy, limitations, and pitfalls associated with FMT studies are further discussed, emphasizing the need for further research and standardization in certain methodological aspects in order to optimize metabolic outcomes.

Effect of Mutant and Engineered High-Acetate-Producing Saccharomyces cerevisiae var. boulardii Strains in Dextran Sodium Sulphate-Induced Colitis

Acetate-producing Saccharomyces cerevisiae var. boulardii strains could exert improved effects on ulcerative colitis, which here, was preclinically evaluated in an acute dextran sodium sulphate induced model of colitis. Nine-week-old female mice were divided into 12 groups, receiving either drinking water or 2.75% dextran sodium sulphate for 7 days, combined with a daily gavage of various treatments with different levels of acetate accumulation: sham control (phosphate buffered saline, no acetate), non-probiotic control (Baker's yeast, no acetate), probiotic control (Enterol®, transient acetate), and additionally several Saccharomyces cerevisiae var. boulardii strains with respectively no, high, and extra-high acetate accumulation. Disease activity was monitored daily, and feces samples were collected at different timepoints. On day 14, the mice were sacrificed, upon which blood and colonic tissue were collected for analysis. Disease activity in inflamed mice was lower when treated with the high-acetate-producing strain compared to sham and non-probiotic controls. The non-acetate-producing strain showed higher disease activity compared to the acetate-producing strains. Accordingly, higher histologic inflammation was observed in non- or transient-acetate-producing strains compared to the sham control, whereas this increase was not observed for high- and extra-high-acetate-producing strains upon induction of inflammation. These anti-inflammatory findings were confirmed by transcriptomic analysis of differentially expressed genes. Moreover, only the strain with the highest acetate production was superior in maintaining a stable gut microbial alpha-diversity upon inflammation. These findings support new possibilities for acetate-mediated management of inflammation in inflammatory bowel disease by administrating high-acetate-producing Saccharomyces cerevisae var. boulardii strains.

Lower fecal microbiota transplantation ameliorates ulcerative colitis by eliminating oral-derived Fusobacterium nucleatum and virulence factor

BACKGROUND

Recently, the oral oncobacterium Fusobacterium nucleatum (F. nucleatum), has been linked with ulcerative colitis (UC). Here, we aim to investigate whether Fecal Microbiota Transplantation (FMT) can alleviate UC by restoring gut microbiota and eliminating oral-derived F. nucleatum and virulence factor fadA.

METHOD

C57BL/6J mice were randomly divided into a healthy control group (HC), Dextran Sulfate Sodium group (DSS), oral inoculation group (OR), upper FMT group (UFMT), and lower FMT group (LFMT). Disease activity index, body weight, survival rate, and histopathological scores were used to measure the severity of colitis. The function of the intestinal mucosal barrier was evaluated by performing immunohistochemical staining of the tight junction protein Occludin. Real-time PCR was used to assess the relative abundance of the nusG gene and the virulence gene fadA. Cytokine levels were detected by ELISA. Full-length sequencing of 16S rRNA was used to analyze the changes and composition of gut microbiota.

FINDINGS

Oral incubation of F. nucleatum further exacerbated the severity of colitis and gut dysbiosis. Peptostreptococcaceae, Enterococcaceae, and Escherichia coli were significantly enriched in OR mice. However, LFMT mice showed an obvious decrease in disease activity and were more effective in restoring gut microbiota and eliminating F. nucleatum than UFMT mice. Bacteroidota, Lachnospiraceae, and Prevotellaceae were mainly enriched bacteria in LFMT mice. In addition, Genera such as Lactobacillus, Allobaculum, and Bacteroidales were found negative correlation with TNF-α, IL-1β, and IL-6. Genera like Romboutsia, Escherichia Shigella, Enterococcus, and Clostridium were found positively correlated with TNF-α, IL-1β, and IL-6.

CONCLUSIONS

Oral incubation of F. nucleatum further exacerbates the severity and dysbiosis in DSS-induced colitis mice. Besides, lower tract FMT can ameliorate colitis by restoring the gut microbiota diversity and eliminating F. nucleatum and virulence factor fadA.

Higher alpha diversity and Lactobacillus blooms are associated with better engraftment after fecal microbiota transplant in inflammatory bowel disease

Fecal Microbiota Transplant (FMT) has shown some success in treating inflammatory bowel diseases (IBD). There is emerging evidence that host engraftment of donor taxa is a tenet of successful FMT. We undertook a double-blind, randomized, placebo-controlled pilot study to characterize the response to FMT in children and young adults with mild to moderate active Crohn's disease (CD) and ulcerative colitis (UC). Subjects with CD or UC were randomized to receive antibiotics and weekly FMT or placebo in addition to baseline medications. We enrolled 15 subjects aged 14-29 years. Four subjects had CD, and 11 had UC. Subjects exhibited a wide range of microbial diversity and donor engraftment. Specifically, engraftment ranged from 26 to 90% at week 2 and 3-92% at 2 months. Consistent with the current literature, increases over time of both alpha diversity (p < 0.05) and donor engraftment (p < 0.05) correlated with improved clinical response. We discovered that the post-antibiotic but pre-FMT time point was rich in microbial correlates of eventual engraftment. Greater residual alpha diversity after antibiotic treatment was positively correlated with engraftment and subsequent clinical response. Interestingly, a transient rise in the relative abundance of Lactobacillus was also positively correlated with engraftment, a finding that we recapitulated with our analysis of another FMT trial.

Healing from Within: How Gut Microbiota Predicts IBD Treatment Success-A Systematic Review

Recent research indicates that the microbiome has a significant impact on the progression of inflammatory bowel disease (IBD) and that creating therapies that change its composition could positively impact the outcomes of IBD treatment. This review summarizes the results of extensive studies that examined IBD patients undergoing several therapies, including anti-TNF medication, vedolizumab, ustekinumab, probiotics, and fecal microbiota transplantation (FMT), and the alterations in their gut microbiota's composition and function. The objective was to investigate the variety and effectiveness of microbial species in order to discover new biomarkers or therapeutic targets that could improve the outcome of treatment for these patients. This research aimed to offer useful insights into personalized medicine techniques for managing IBD. Beneficial bacteria such as Faecalibacterium prausnitzii and Roseburia have been consistently linked to favorable clinical outcomes, whereas pathogenic bacteria such as Escherichia coli and Clostridioides difficile are associated with worsening disease conditions. Although many studies have examined the role of gut microbiota in IBD, there is still a need for more targeted research on the connection between specific microbial communities and treatment outcomes. This study sought to address this gap by exploring the intricate relationship between the gut microbiota composition and the effectiveness of IBD medications.

A viable remedy for overcoming resistance to anti-PD-1 immunotherapy: Fecal microbiota transplantation

Anti-PD-1 immunotherapy is a cancer therapy that focuses explicitly on the PD-1 receptor found on the surface of immune cells. This targeted therapeutic strategy is specifically designed to amplify the immune system's innate capacity to detect and subsequently eliminate cells that have become cancerous. Nevertheless, it should be noted that not all patients exhibit a favourable response to this particular therapeutic modality, necessitating the exploration of novel strategies to augment the effectiveness of immunotherapy. Previous studies have shown that fecal microbiota transplantation (FMT) can enhance the efficacy of anti-PD-1 immunotherapy in advanced melanoma patients. To investigate this intriguing possibility further, we turned to PubMed and conducted a comprehensive search for studies that analyzed the interplay between FMT and anti-PD-1 therapy in the context of tumor treatment. Our search criteria were centred around two key phrases: "fecal microbiota transplantation" and "anti-PD-1 therapy." The studies we uncovered all echo a similar sentiment. They pointed towards the potential of FMT to improve the effectiveness of immunotherapy. FMT may enhance the effectiveness of immunotherapy by altering the gut microbiota and boosting the patient's immunological response. Although promising, additional investigation is needed to improve the efficacy of FMT in the context of cancer therapy and attain a comprehensive understanding of the possible advantages and drawbacks associated with this therapeutic strategy.

The importance of food quality, gut motility, and microbiome in SIBO development and treatment

The prevalence of small intestinal bacterial overgrowth (SIBO) is rising worldwide, particularly in nations with high rates of urbanization. Irritable bowel syndrome, inflammatory bowel illnesses, and nonspecific dysmotility are strongly linked to SIBO. Moreover, repeated antibiotic therapy promotes microorganisms' overgrowth through the development of antibiotic resistance. The primary cause of excessive fermentation in the small intestine is a malfunctioning gastrointestinal motor complex, which results in the gut's longer retention of food residues. There are anatomical and physiological factors affecting the functioning of the myoelectric motor complex. Except for them, diet conditions the activity of gastrointestinal transit. Indisputably, the Western type of nutrition is unfavorable. Some food components have greater importance in the functioning of the gastrointestinal motor complex than others. Tryptophan, an essential amino acid and precursor of the serotonin hormone, accelerates intestinal transit, and gastric emptying, similarly to fiber and polyphenols. Additionally, the effect of food on the microbiome is important, and diet should prevent bacterial overgrowth and exhibit antimicrobial effects against pathogens. Therefore, knowledge about proper nutrition is essential to prevent the development and recurrence of SIBO. Since the scientific world was unsure whether there was a long-term or potential solution for SIBO until quite recently, research on a number of the topics included in the article should be performed. The article aimed to summarize current knowledge about proper nutrition after SIBO eradication and the prevention of recurrent bacterial overgrowth. Moreover, a connection was found between diet, gut dysmotility, and SIBO.

Chinese guidelines for integrated diagnosis and treatment of intestinal microecology technologies in tumor application (2024 Edition)

ABSTRACT

Intestinal microecology (IM) is the largest and most important microecological system of the human body. Furthermore, it is the key factor for activating and maintaining the physiological functions of the intestine. Numerous studies have investigated the effects of the gut microbiota on the different tissues and organs of the human body as well as their association with various diseases, and the findings are gradually being translated into clinical practice. The gut microbiota affects the occurrence, progression, treatment response, and toxic side effects of tumors. The deepening of research related to IM and tumors has opened a new chapter in IM research driven by methods and technologies such as second-generation sequencing and bioinformatics. The IM maintains the function of the host immune system and plays a pivotal role in tumor-control drug therapy. Increasing evidence has proven that the efficacy of tumor-control drugs largely depends on the IM balance, and strategies based on the IM technology show promising application prospects in the diagnosis and treatment of tumor. The Tumor and Microecology Professional Committee of the Chinese Anti-cancer Association gathered relevant experts to discuss and propose the "Chinese guidelines for integrated diagnosis and treatment of IM technologies in tumor application (2024 Edition)," which was established based on the research progress of the application of the IM technology in tumor to provide a basis for the standardization of the diagnosis and treatment of the IM technology in the tumor.

Cmtm4 deficiency exacerbates colitis by inducing gut dysbiosis and S100a8/9 expression

The dysfunction of innate immunity components is one of the major drivers for ulcerative colitis (UC), and increasing reports indicate that the gut microbiome serves as an intermediate between genetic mutations and UC development. Here, we find that the IL-17 receptor subunit, CMTM4, is reduced in UC patients and dextran sulfate sodium (DSS)-induced colitis. The deletion of CMTM4 (Cmtm4-/-) in mice leads to a higher susceptibility to DSS-induced colitis than in wild-type, and the gut microbiome significantly changes in composition. The causal role of the gut microbiome is confirmed with a cohousing experiment. We further identify that S100a8/9 is significantly up-regulated in Cmtm4-/- colitis, with the block of its receptor RAGE that reverses the phenotype associated with the CMTM4 deficiency. CMTM4 deficiency rather suppresses S100a8/9 expression in vitro via the IL17 pathway, further supporting that the elevation of S100a8/9 in vivo is most likely a result of microbial dysbiosis. Taken together, the results suggest that CMTM4 is involved in the maintenance of intestinal homeostasis, suppression of S100a8/9, and prevention of colitis development. Our study further shows CMTM4 as a crucial innate immunity component, confirming its important role in UC development and providing insights into potential targets for the development of future therapies.

Letter: Microbial manipulation for primary sclerosing cholangitis-associated inflammatory bowel disease-hope on the horizon

This article is linked to Ricciuto et al paper. To view this article, visit https://doi.org/10.1111/apt.17936

The influence of aging and the microbiome in multiple sclerosis and other neurologic diseases

The human gut microbiome is well-recognized as a key player in maintaining health. However, it is a dynamic entity that changes across the lifespan. How the microbial changes that occur in later decades of life shape host health or impact age-associated inflammatory neurological diseases such as multiple sclerosis (MS) is still unclear. Current understanding of the aging gut microbiome is largely limited to cross-sectional observational studies. Moreover, studies in humans are limited by confounding host-intrinsic and extrinsic factors that are not easily disentangled from aging. This review provides a comprehensive summary of existing literature on the aging gut microbiome and its known relationships with neurological diseases, with a specific focus on MS. We will also discuss preclinical animal models and human studies that shed light on the complex microbiota-host interactions that have the potential to influence disease pathology and progression in aging individuals. Lastly, we propose potential avenues of investigation to deconvolute features of an aging microbiota that contribute to disease, or alternatively promote health in advanced age.

The gut microbiota-bile acid axis in cholestatic liver disease

Cholestatic liver diseases (CLD) are characterized by impaired normal bile flow, culminating in excessive accumulation of toxic bile acids. The majority of patients with CLD ultimately progress to liver cirrhosis and hepatic failure, necessitating liver transplantation due to the lack of effective treatment. Recent investigations have underscored the pivotal role of the gut microbiota-bile acid axis in the progression of hepatic fibrosis via various pathways. The obstruction of bile drainage can induce gut microbiota dysbiosis and disrupt the intestinal mucosal barrier, leading to bacteria translocation. The microbial translocation activates the immune response and promotes liver fibrosis progression. The identification of therapeutic targets for modulating the gut microbiota-bile acid axis represents a promising strategy to ameliorate or perhaps reverse liver fibrosis in CLD. This review focuses on the mechanisms in the gut microbiota-bile acids axis in CLD and highlights potential therapeutic targets, aiming to lay a foundation for innovative treatment approaches.

The Role of Nondigestible Oligosaccharides in Alleviating Human Chronic Diseases by Regulating the Gut Microbiota: A Review

The gut has been a focus of chronic disease research. The gut microbiota produces metabolites that act as signaling molecules and substrates, closely influencing host health. Nondigestible oligosaccharides (NDOs), as a common dietary fiber, play an important role in regulating the structure and function of the gut microbiota. Their mechanism of action is mainly attributed to providing a carbon source as specific probiotics, producing related metabolites, and regulating the gut microbial community. However, due to the selective utilization of oligosaccharides, some factors, such as the type and structure of oligosaccharides, have different impacts on the composition of microbial populations and the production of metabolites in the colon ecosystem. This review systematically describes the key factors influencing the selective utilization of oligosaccharides by microorganisms and elaborates how oligosaccharides affect the host's immune system, inflammation levels, and energy metabolism by regulating microbial diversity and metabolic function, which in turn affects the onset and progress of chronic diseases, especially diabetes, obesity, depression, intestinal inflammatory diseases, and constipation. In this review, we re-examine the interaction mechanisms between the gut microbiota and its associated metabolites and diseases, and we explore new strategies for promoting human health and combating chronic diseases through dietary interventions.

Microbiome-based therapies for periodontitis and peri-implantitis

OBJECTIVES

Periodontitis and peri-implantitis are oral infectious-inflammatory diseases associated with oral microbial dysbiosis. Microbiome-based therapies, characterized by manipulation of the microbiota, are emerging as promising therapeutic approaches to resolve the microbial dysbiosis and associated dysregulation of immune system. This review aims at summarizing recent progress on microbiome-based therapies in periodontitis and peri-implantitis, promoting a further understanding of the related therapeutic mechanisms.

SUBJECTS AND METHODS

Pertinent literatures focused on microbiome-based therapies for periodontitis and peri-implantitis are obtained from PubMed and Web of Science.

RESULTS

In this article, we review the roles and therapeutic mechanisms of four microbiome-based therapies, including probiotics, postbiotics, predatory bacteria and phages, and microbiota transplantation, in the management of periodontitis and peri-implantitis. Challenges facing this field are also discussed, highlighting the areas that require more attention and investigation.

CONCLUSIONS

Microbiome-based therapies may serve as effective treatment for periodontitis and peri-implantitis. This review presents a new viewpoint to this field.

Current and future microbiome-based therapies in inflammatory bowel disease

PURPOSE OF REVIEW

The role of the microbiome and dysbiosis is increasingly recognized in the pathogenesis of inflammatory bowel disease (IBD). Intestinal microbiota transplant (IMT), previously termed fecal microbiota transplant has demonstrated efficacy in restoring a healthy microbiome and promoting gut health in recurrent Clostridioides difficile infection. Several randomized trials (RCTs) highlighted IMT's potential in treating ulcerative colitis, while smaller studies reported on its application in managing Crohn's disease and pouchitis.

RECENT FINDINGS

This review delves into the current understanding of dysbiosis in IBD, highlighting the distinctions in the microbiota of patients with IBD compared to healthy controls. It explores the mechanisms by which IMT can restore a healthy microbiome and provides a focused analysis of recent RCTs using IMT for inducing and maintaining remission in IBD. Lastly, we discuss the current knowledge gaps that limit its widespread use.

SUMMARY

The body of evidence supporting the use of IMT in IBD is growing. The lack of a standardized protocol impedes its application beyond clinical trials. Further research is needed to identify patient profile and disease phenotypes that benefit from IMT, to delineate key donor characteristics, optimize the delivery route, dosage, and frequency.

Advances in single-cell sequencing technology in microbiome research

With the rapid development of histological techniques and the widespread application of single-cell sequencing in eukaryotes, researchers desire to explore individual microbial genotypes and functional expression, which deepens our understanding of microorganisms. In this review, the history of the development of microbial detection technologies was revealed and the difficulties in the application of single-cell sequencing in microorganisms were dissected as well. Moreover, the characteristics of the currently emerging microbial single-cell sequencing (Microbe-seq) technology were summarized, and the prospects of the application of Microbe-seq in microorganisms were distilled based on the current development status. Despite its mature development, the Microbe-seq technology was still in the optimization stage. A retrospective study was conducted, aiming to promote the widespread application of single-cell sequencing in microorganisms and facilitate further improvement in the technology.

Melanin Nanoparticle-Modified Probiotics for Targeted Synergistic Therapy of Ulcerative Colitis

Ulcerative colitis (UC) is a recurrent chronic mucosal inflammation disease whose most significant pathological characteristics are intestinal inflammation and damaged mucosal barrier induced by reactive oxygen/nitrogen species, abnormal immune microenvironment, and intestinal microecological imbalance. Oral probiotics are a living therapy for intestinal diseases, but their clinical application is hindered by poor bacterial biological activity and insufficient intestinal retention. Here, we developed a targeted oral formulation, functionalized probiotic Lf@MPB, with Lactobacillus fermentum (Lf) as the core and modified melanin nanoparticles (MNPs) on its surface through a click reaction of tricarboxyphenylboronic acid for synergistic therapy of UC. In vitro experiments showed that Lf@MPB not only possessed strong free radical scavenging ability, reduced cellular mitochondrial polarization, and inhibited apoptosis but also significantly enhanced the viability of Lf probiotics in simulated gastrointestinal fluid. Fluorescence imaging in vivo revealed the high accumulation of Lf@MPB at the site of intestinal inflammation in dextran sulfate sodium-induced UC mice. Moreover, in vivo results demonstrated that Lf@MPB effectively alleviated oxidative stress and inflammatory response and restored the intestinal barrier. In addition, 16S rRNA gene sequencing verified that Lf@MPB could increase the abundance and diversity of intestinal microbial communities and optimize microbial composition to inhibit the progression of UC. This work combines effective antioxidant and anti-inflammatory strategies with the oral administration of functionalized probiotics to provide a promising alternative for UC treatment.

Encapsulation protocol for fecal microbiota transplantation

Introduction

Clostridioides difficile infections (CDI) continue to pose a challenge for clinicians. Fecal microbiota transplantation (FMT) is an effective treatment option in CDI. Furthermore, recent and ongoing studies suggest potential benefits of FMT in other diseases as well.

Methods

We would like to present a novel protocol for encapsulation of lyophilized fecal material. Our method provides with better compliance as well as improved flexibility, storage and safety.

Results

FMT was conducted in 28 patients with an overall success rate of 82,14% using apsules containing lyophilized stool. 16 of patients were given capsules with lessened bacteria counts. The success rate in this group was 93,75%.

Discussion

The results highlight the still unanswered questions about the mechanism of action and contribute to a wider use of FMT in the clinical praxis and in research.