The Effects of Fecal Microbiota Transplantation on the Symptoms and the Duodenal Neurogenin 3, Musashi 1, and Enteroendocrine Cells in Patients With Diarrhea-Predominant Irritable Bowel Syndrome

Gut microbiota and intestinal immunity-A crosstalk in irritable bowel syndrome

Irritable bowel syndrome (IBS), one of the most prevalent functional gastrointestinal disorders, is characterized by recurrent abdominal pain and abnormal defecation habits, resulting in a severe healthcare burden worldwide. The pathophysiological mechanisms of IBS are multi-factorially involved, including food antigens, visceral hypersensitivity reactions, and the brain-gut axis. Numerous studies have found that gut microbiota and intestinal mucosal immunity play an important role in the development of IBS in crosstalk with multiple mechanisms. Therefore, based on existing evidence, this paper elaborates that the damage and activation of intestinal mucosal immunity and the disturbance of gut microbiota are closely related to the progression of IBS. Combined with the application prospect, it also provides references for further in-depth exploration and clinical practice.

Fecal microbiota transplantation for the treatment of irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is the most prevalent gastrointestinal disorder in developed countries and reduces patients’ quality of life, hinders their ability to work, and increases health care costs. A growing number of trials have demonstrated an aberrant gut microbiota composition in IBS, also known as ‘gut dysbiosis’. Fecal microbiota transplantation (FMT) has been suggested as a treatment for IBS.

AIM

To assess the efficacy and safety of FMT for the treatment of IBS.

METHODS

We searched Cochrane Central, MEDLINE, EMBASE and Web of Science up to 24 October 2022 for randomised controlled trials (RCTs) investigating the effectiveness of FMT compared to placebo (including autologous FMT) in treating IBS. The primary outcome was the number of patients with improvements of symptoms measured using a validated, global IBS symptoms score. Secondary outcomes were changes in quality-of-life scores, non-serious and serious adverse events. Risk ratios (RR) and corresponding 95%CI were calculated for dichotomous outcomes, as were the mean differences (MD) and 95%CI for continuous outcomes. The Cochrane risk of bias tool was used to assess the quality of the trials. GRADE criteria were used to assess the overall quality of the evidence.

RESULTS

Eight RCTs (484 participants) were included in the review. FMT resulted in no significant benefit in IBS symptoms three months after treatment compared to placebo (RR 1.19, 95%CI: 0.68-2.10). Adverse events were reported in 97 participants in the FMT group and in 45 participants in the placebo group (RR 1.17, 95%CI: 0.63-2.15). One serious adverse event occurred in the FMT group and two in the placebo group (RR 0.42, 95%CI: 0.07-2.60). Endoscopic FMT delivery resulted in a significant improvement in symptoms, while capsules did not. FMT did not improve the quality of life of IBS patients but, instead, appeared to reduce it, albeit non significantly (MD -6.30, 95%CI: -13.39-0.79). The overall quality of the evidence was low due to moderate-high inconsistency, the small number of patients in the studies, and imprecision.

CONCLUSION

We found insufficient evidence to support or refute the use of FMT for IBS. Larger trials are needed.

Gut microbiota: a new avenue to reveal pathological mechanisms of constipation

Constipation is very pervasive all over the world. It is a common multifactorial gastrointestinal disease, and its etiology and pathomechanism are not completely clear. Now, increasing evidence shows that intestinal flora is closely related to constipation. Intestinal flora is the largest microbiota in the human body and has powerful metabolic functions. Intestinal flora can produce a variety of metabolites, such as bile acids, short-chain fatty acids, tryptophan metabolites, and methane, which have important effects on intestinal motility and secretion. The host can also monitor the intestinal flora and regulate gut dysbacteriosis in constipation. To explore the relationship between intestinal flora and host, the combination of multiomics technology has become the powerful and effective method. Furthermore, the homeostasis restoration of intestinal flora also provides a new strategy for the treatment of constipation. This review aims to explore the interaction between intestinal flora and host in constipation, which contributes to disclose the pathogenesis of constipation and the development of novel drugs for the treatment of constipation from the perspective of intestinal flora. KEY POINTS: • This review highlights the regulation of gut microbiota on the intestinal motility and secretion of host. • The current review gives an insight into the role of the host on the recognition and regulation of intestinal ecology under constipation. • The article also introduces some novel methods of current gut microbiota research and gut microbiota-based constipation therapies.

Changes in colonic enteroendocrine cells of patients with irritable bowel syndrome following fecal microbiota transplantation

OBJECTIVES

The aim was to investigate the effect of fecal microbiota transplantation (FMT) on colonic enteroendocrine cells densities in patients with irritable bowel syndrome (IBS).

MATERIALS AND METHODS

This study is connected to the REFIT study, a double-blinded placebo-controlled trial to investigate using FMT for IBS treatment. Eighty-three subjects received either donor-FMT or placebo FMT (own feces) by colonoscope to cecum. Biopsies were obtained from sigmoid colon. Ten responders and ten non-responders consented to new biopsy one-year after FMT. Sixteen patients received donor-FMT and four received placebo FMT. Biopsies were immunostained for all of the colonic enteroendocrine cells and were quantified using computerized image analysis.Allocation sequence was revealed after obtaining re-biopsies and cells quantification.

RESULTS

Scores for IBS-SSS (mean ± SEM) of responders (eight of 10 patients who received donor FMT) and non-responders changed from baseline to one year after FMT (297 ± 11 and 81 ± 16, p < .0001, and 270 ± 17 and 291 ± 16, p = .15, respectively). Using paired t-test to compare enteroendocrine cells densities one-year after FMT to baseline showed significant increase only in somatostatin immunoreactive cells density in the total IBS responders group (p = .023) and who received donor-FMT (p = .038). The densities of peptide YY and enteroglucagon immunoreactive cells increased significantly (p = .04 and .035, respectively) in donor-FMT recipients. No significant changes were noted in placebo FMT or nonresponders subgroups.

CONCLUSION

This study shows that colonic enteroendocrine cells densities significantly change in responders group that received donor-FMT. The mechanisms for the cross talks between gut microbiota and colonic enteroendocrine cells remain to be investigated.

Gut Microbiota Manipulation in Irritable Bowel Syndrome

Increased knowledge suggests that disturbed gut microbiota, termed dysbiosis, might promote the development of irritable bowel syndrome (IBS) symptoms. Accordingly, gut microbiota manipulation has evolved in the last decade as a novel treatment strategy in order to improve IBS symptoms. In using different approaches, dietary management stands first in line, including dietary fiber supplements, prebiotics, and probiotics that are shown to change the composition of gut microbiota, fecal short-chain fatty acids and enteroendocrine cells densities and improve IBS symptoms. However, the exact mixture of beneficial bacteria for each individual remains to be identified. Prescribing nonabsorbable antibiotics still needs confirmation, although using rifaximin has been approved for diarrhea-predominant IBS. Fecal microbiota transplantation (FMT) has recently gained a lot of attention, and five out of seven placebo-controlled trials investigating FMT in IBS obtain promising results regarding symptom reduction and gut microbiota manipulation. However, more data, including larger cohorts and studying long-term effects, are needed before FMT can be regarded as a treatment for IBS in clinical practice.

Global Research Trends in Irritable Bowel Syndrome: A Bibliometric and Visualized Study

Background

There are about 10–23% of adults worldwide suffering from irritable bowel syndrome (IBS). Over the past few decades, there are many aspects of uncertainty regarding IBS leading to an ongoing interest in the topic as reflected by a vast number of publications, whose heterogeneity and variable quality may challenge researchers to measure their scientific impact, to identify collaborative networks, and to grasp actively researched themes. Accordingly, with help from bibliometric approaches, our goal is to assess the structure, evolution, and trends of IBS research between 2007 and 2022.

Methods

The documents exclusively focusing on IBS from 2007 to 2022 were retrieved from the Science Citation Index Expanded of the Web of Science Core Collection. The annual productivity of IBS research, and the most prolific countries or regions, authors, journals and resource-, intellectual- and knowledge-sharing in IBS research, as well as co-citation analysis of references and keywords were analyzed through Microsoft Office Excel 2019, CiteSpace, and VOSviewer.

Results

In total, 4,092 publications were reviewed. The USA led the list of countries with the most publications (1,226, 29.96%). Mayo Clinic contributed more publications than any other institution (193, 4.71%). MAGNUS SIMREN stood out as the most active and impactful scholar with the highest number of publications and the greatest betweenness centrality value. The most high-yield journal in this field was Neurogastroenterology and motility: the official journal of the European Gastrointestinal Motility Society (275, 6.72%). Gastroenterology had the most co-citations (3,721, 3.60%). Keywords with the ongoing strong citation bursts were chromogranin A, rat model, peptide YY, gut microbiota, and low-FODMAP diet, etc.

Conclusion

Through bibliometric analysis, we gleaned deep insight into the current status of literature investigating IBS for the first time. These findings will be useful to scholars interested in understanding the key information in the field, as well as identifying possible research frontiers.

Efficacy of Fecal Microbiota Transplantation in Irritable Bowel Syndrome Patients: An Updated Systematic Review and Meta-Analysis

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disease characterized by abdominal discomfort and bloating, diarrhea, and/or constipation. Fecal microbiota transplantation (FMT) is transferring the fecal bacteria and other microorganisms from a healthy person to another. We performed this systematic review and meta-analysis to assess the efficacy of FMT in treating IBS patients. We searched Scopus, PubMed, Cochrane, and Web of Science databases through June 2021 using relevant key words. We included 19 studies. Fecal microbiota transplantation was significantly superior to placebo in IBS quality of life after 4 weeks (mean difference [MD] = 7.47, 95% confidence interval [CI]: 2.05-12.89, p = .04), 12 weeks (MD = 9.99, 95% CI: 5.78-14.19, p < .00001), and 24 weeks (MD = 8.49, 95% CI: 0.47-16.52, p = .04), with no difference regarding IBS improvement symptoms and the IBS Severity Scoring System (SSS). Single-arm analysis revealed that the incidence of improvement of IBS symptoms was 57.8% (45.6%-69.9%) with reduction in IBS-SSS (MD = -74, 95% CI: -101.7 to -46.3). Fecal microbiota transplantation was superior to placebo in improving quality of life after 4, 12, and 24 weeks. Also, FMT improved IBS symptoms and reduced the IBS-SSS score. However, no deference was detected between FMT and placebo in IBS-SSS score and IBS symptoms improvement.

Differential effect of polysaccharide and nonpolysaccharide components in Sijunzi decoction on spleen deficiency syndrome and their mechanisms

BACKGROUND

Sijunzi decoction (SJZD), reported in "Tai Ping Hui Min He Ji Ju Fang" of the Song dynasty, is the basic prescription for the treatment of spleen deficiency syndrome (SDS) in traditional Chinese medicine (TCM). It is composed of Ginseng Radix et Rhizoma, Atractylodisa Macricephalae Rhizoma, Poria and Glycyrrhizae Radix et Rhizoma Praeparata Cum Melle.

PURPOSE

This study sought to explore the effects of different components in SJZD (including nonpolysaccharide NPS and active polysaccharide S-3) on SDS rats and their underlying mechanisms.

STUDY DESIGN AND METHODS

First, SDS model rats were established by reserpine injection and then treated with SJZD, NPS and S-3. To clarify their effect on GI motility and immune function, the gastrointestinal (GI) hormone levels in rat serum and their related receptor expressions in rat intestine were detected by enzyme-linked immunosorbent assay (ELISA) and western blot, and the intestinal T lymphocyte expression were quantified by flow cytometry. The levels of SCFAs in feces and serum were measured by gas chromatography-mass spectrometry (GC-MS), and the gut microbiota composition was determined by 16S RNA sequencing. Furthermore, pseudo-germ-free (pGF) and gut microbiota dysbiosis (GMD) model rats were established to verify the key role of the gut microbiota in the treatment of SDS with SJZD, NPS and S-3.

RESULTS

SJZD has a stronger therapeutic effect on intestinal immune and GI hormone secretion in SDS rats, while the efficacy of NPS and S-3 showed slight differences. NPS mainly regulated the secretion of GI hormones in SDS rats and directly improved intestinal immunity by increasing the expression of T lymphocyte cells, while S-3 mainly enhanced intestinal immune function by increasing the expression of T lymphocyte cells and repairing the intestinal barrier in both direct and indirect ways. Additionally, experiments in pGF and GMD rats have proven that the immune-enhancing effects of SJZD, NPS, and S-3 on SDS rats and the regulation of GI hormones of S-3 are related to modulation of the gut microbiota composition, while the regulation of GI hormones by SJZD and NPS is not completely dependent on this modulation. In particular, Lactobacillus, SMB53, Blautia, Dorea, Collinsella and Adlercreutzia were significantly modulated by SJZD, and 3 genera (including Lactobacillus, Dorea and SMB53) were also remarkably regulated by NPS. S-3 significantly increased the abundance of Butyricimonas and Collinsella, which were different from altered genera in the SJZD group.

CONCLUSION

This study uncovered that NPS and S-3 are inseparable effective substances for SJZD in the treatment of SDS rats, in which NPS mainly improves intestinal motility dysfunction and S-3 mainly enhances intestinal immunity. The mediation effect of the gut microbiota is extremely important, but the regulating effect of NPS on gastrointestinal hormones has nothing to do with the gut microbiota.