Diet-induced modifications to human microbiome reshape colonic homeostasis in irritable bowel syndrome

Changes in microbiome composition have been associated with a wide array of human diseases, turning the human microbiota into an attractive target for therapeutic intervention. Yet clinical translation of these findings requires the establishment of causative connections between specific microbial taxa and their functional impact on host tissues. Here, we colonized gut organ cultures with longitudinal microbiota samples collected from newly-diagnosed and therapy-naive irritable bowel syndrome (IBS) patients under low-FODMAP (fermentable Oligo-, Di-, Mono-saccharides and Polyols) diet. We show that post-diet microbiota regulates intestinal expression of inflammatory and neuro-muscular gene-sets. Specifically, we identify Bifidobacterium adolescentis as a diet-sensitive pathobiont that alters tight junction integrity and disrupts gut barrier functions. Collectively, we present a unique pathway discovery approach for mechanistic dissection and identification of functional diet-host-microbiota modules. Our data support the hypothesis that the gut microbiota mediates the beneficial effects of low-FODMAP diet, and reinforce the potential feasibility of microbiome based-therapies in IBS.

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Does Fibre-fix provided to people with irritable bowel syndrome who are consuming a low FODMAP diet improve their gut health, gut microbiome, sleep and mental health? A double-blinded, randomised controlled trial

BMJ Open Gastroenterology ◽

10.1136/bmjgast-2020-000448 ◽

2020 ◽

Vol 7 (1) ◽

pp. e000448

Author(s):

Ran Yan ◽

Mandy Murphy ◽

Angela Genoni ◽

Evania Marlow ◽

Ian C Dunican ◽

...

Keyword(s):

Mental Health ◽

Irritable Bowel Syndrome ◽

Gut Microbiome ◽

Controlled Study ◽

Gut Health ◽

Management Options ◽

Microbiome Composition ◽

Bowel Symptoms ◽

Irritable Bowel ◽

Fodmap Diet

IntroductionA diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) is an effective way to reduce gut symptoms in people with irritable bowel syndrome (IBS). This diet reduces the intake of fermentable fibres, leading to changes of the gut microbiota and insufficient fermentation in the large bowel, resulting in reduced production of short-chain fatty acids (SCFAs), such as butyrate, which has unfavourable implications for gut health, sleep and mental health. This study will examine the effect of Fibre-fix, a supplement containing a mix of dietary fibres, on the human gut microbiome composition, fermentative capacity, sleep, quality of life (QOL) and mental health of people with IBS who consume a low FODMAP diet (LFD).Methods and analysisA randomised, double-blind, placebo-controlled, study design is proposed to examine whether Fibre-fix added to an existing LFD may help modulate gastrointestinal function, improve markers of sleep, mental health and promote QOL in patients with IBS. Participants will provide stool and blood samples, daily bowel symptoms diaries and 3-day diet records. Additionally, they will complete validated questionnaires relating to FODMAP intake, sleep, mental health and QOL before and after a 3-week intervention. Gut health will be assessed via faecal microbiome composition, faecal pH and SCFA levels. Alteration of sleep will be recorded using an actigraphy device worn by all participants over the whole study. Multivariate analysis will be used to examine the gut microbiome and repeated measures Analysis of variance (ANOVA) will be used for dependent variables from questionnaires related to bowel symptoms, stool type, sleep, mental health and QOL to assess the differences between intervention and control groups after adjustment for confounding variables.Ethics and disseminationEthics approval was obtained from the Human Research Ethics Committee of Edith Cowan University (2019-00619-YAN). Results will be disseminated in peer-review journal publications, and conference presentations. Participants will be provided with a summary of findings once the study is completed. If Fibre-fix is shown to result in favourable changes in gut microbial composition, SCFA production, sleep and mental well-being without exacerbating symptoms, this will provide additional dietary management options for those with IBS following an LFD.Trial registration numberACTRN12620000032954.

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Diarrhea Predominant-Irritable Bowel Syndrome (IBS-D): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Nutrients ◽

10.3390/nu13051506 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1506

Author(s):

Annamaria Altomare ◽

Claudia Di Rosa ◽

Elena Imperia ◽

Sara Emerenziani ◽

Michele Cicala ◽

...

Keyword(s):

Irritable Bowel Syndrome ◽

Intestinal Microbiota ◽

Gastrointestinal Disorder ◽

Additional Energy ◽

Nutritional Advice ◽

Intestinal Dysbiosis ◽

Gi Symptoms ◽

Mutualistic Relationship ◽

Irritable Bowel ◽

Fodmap Diet

Irritable Bowel Syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. Gut microbiota, which acts as a real organ with well-defined functions, is in a mutualistic relationship with the host, harvesting additional energy and nutrients from the diet and protecting the host from pathogens; specific alterations in its composition seem to play a crucial role in IBS pathophysiology. It is well known that diet can significantly modulate the intestinal microbiota profile but it is less known how different nutritional approach effective in IBS patients, such as the low-FODMAP diet, could be responsible of intestinal microbiota changes, thus influencing the presence of gastrointestinal (GI) symptoms. The aim of this review was to explore the effects of different nutritional protocols (e.g., traditional nutritional advice, low-FODMAP diet, gluten-free diet, etc.) on IBS-D symptoms and on intestinal microbiota variations in both IBS-D patients and healthy subjects. To date, an ideal nutritional protocol does not exist for IBS-D patients but it seems crucial to consider the effect of the different nutritional approaches on the intestinal microbiota composition to better define an efficient strategy to manage this functional disorder.

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Irritable bowel syndrome: new insights into symptom mechanisms and advances in treatment

F1000Research ◽

10.12688/f1000research.7992.1 ◽

2016 ◽

Vol 5 ◽

pp. 780 ◽

Cited By ~ 15

Author(s):

Robin Spiller

Keyword(s):

Irritable Bowel Syndrome ◽

New Agents ◽

Enteric Nerves ◽

Inflammatory Bowel ◽

Magnetic Resonance Imaging Mri ◽

Irritable Bowel ◽

Fodmap Diet ◽

And Function ◽

The Impact

Despite being one of the most common conditions leading to gastroenterological referral, irritable bowel syndrome (IBS) is poorly understood. However, recent years have seen major advances. These include new understanding of the role of both inflammation and altered microbiota as well as the impact of dietary intolerances as illuminated by magnetic resonance imaging (MRI), which has thrown new light on IBS. This article will review new data on how excessive bile acid secretion mediates diarrhea and evidence from post infectious IBS which has shown how gut inflammation can alter gut microbiota and function. Studies of patients with inflammatory bowel disease (IBD) have also shown that even when inflammation is in remission, the altered enteric nerves and abnormal microbiota can generate IBS-like symptoms. The efficacy of the low FODMAP diet as a treatment for bloating, flatulence, and abdominal discomfort has been demonstrated by randomized controlled trials. MRI studies, which can quantify intestinal volumes, have provided new insights into how FODMAPs cause symptoms. This article will focus on these areas together with recent trials of new agents, which this author believes will alter clinical practice within the foreseeable future.

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Clinical Application of Dietary Therapies in Irritable Bowel Syndrome

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.273.avy ◽

2018 ◽

Vol 27 (3) ◽

pp. 307-316 ◽

Cited By ~ 12

Author(s):

Anupam Rej ◽

Amanda Avery ◽

Alexander Charles Ford ◽

Anne Holdoway ◽

Matthew Kurien ◽

...

Keyword(s):

Irritable Bowel Syndrome ◽

Randomized Trials ◽

Individual Therapy ◽

Dietary Therapy ◽

Round Table Discussion ◽

Mesh Terms ◽

Number Of Patients ◽

Significant Difference ◽

Irritable Bowel ◽

Fodmap Diet

Background & Aims: Diet appears to play a pivotal role in symptom generation in Irritable Bowel Syndrome (IBS). First line dietary therapy for IBS has focused on advice concerning healthy eating and lifestyle management. Research recently has focused on the role of a diet low in fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs), gluten free (GFD) and wheat free (WFD) diets for the relief of symptoms in IBS.Methods: A round table discussion with gastroenterologists and dietitians with a specialist interest in dietary therapies in IBS was held in Sheffield, United Kingdom in May 2017. Existing literature was reviewed. PubMed and EMBASE were searched with the MeSH terms irritable bowel syndrome/diet/diet therapy/gluten/low FODMAP in different combinations to identify relevant articles. A consensus on the application of these dietary therapies into day-to-day practice was developed. Results: Fourteen randomized trials in IBS evaluating the low FODMAP diet (n studies = 9), GFD (n = 4) and WFD (n = 1) were included in this review. The total number of patients recruited from randomized trials reviewed was: n=580 low FODMAP diet (female, n=430), n=203 GFD (female, n=139), n=276 WFD (female, n=215). There was no significant difference in the gender of patients recruited for both the low FODMAP and GFD randomized studies (p=0.12). The response rate in the literature to a low FODMAP diet ranged between 50-76%, and to GFD ranged between 34-71%. Percentage of IBS patients identified as wheat sensitive was reported as 30% in the literature. Conclusion: There are no head-to-head trials to date utilizing the low FODMAP diet, GFD and WFD for dietary treatment of IBS and still a number of concerns for diets, including nutritional inadequacy and alteration of the gut microbiota. The consensus suggests that there is evidence for the use of the low FODMAP diet, GFD and WFD as dietary therapies for IBS; the decision-making process for using each individual therapy should be directed by a detailed history by the dietitian, involving the patient in the process.

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Letter: bias in clinical trials of the symptomatic effects of the low FODMAP diet for irritable bowel syndrome-getting the facts right

Alimentary Pharmacology & Therapeutics ◽

10.1111/apt.14150 ◽

2017 ◽

Vol 46 (3) ◽

pp. 385-386 ◽

Cited By ~ 3

Author(s):

P. R. Gibson ◽

E. P. Halmos ◽

J. G. Muir

Keyword(s):

Clinical Trials ◽

Irritable Bowel Syndrome ◽

Irritable Bowel ◽

Fodmap Diet

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Applying a Low-FODMAP Dietary Intervention to a Female Ultraendurance Runner With Irritable Bowel Syndrome During a Multistage Ultramarathon

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2017-0398 ◽

2019 ◽

Vol 29 (1) ◽

pp. 61-67 ◽

Cited By ~ 5

Author(s):

Stephanie K. Gaskell ◽

Ricardo J.S. Costa

Keyword(s):

Irritable Bowel Syndrome ◽

Dietary Intervention ◽

Gastrointestinal Symptoms ◽

Irritable Bowel Syndrome Symptom ◽

Carbohydrate Intake ◽

Severe Nausea ◽

Dietary Analysis ◽

Irritable Bowel ◽

Fodmap Diet ◽

The Impact

Malabsorption of fermentable oligo-, di-, mono-saccharides and polyols (FODMAPs) in response to prolonged exercise may increase incidence of upper and lower gastrointestinal symptoms (GIS), which are known to impair exercise performance. This case study aimed to explore the impact of a low-FODMAP diet on exercise-associated GIS in a female ultraendurance runner diagnosed with irritable bowel syndrome, competing in a 6-day 186.7-km mountainous multistage ultramarathon (MSUM). Irritable bowel syndrome symptom severity score at diagnosis was 410 and following a low-FODMAP diet (3.9 g FODMAPs/day) it reduced to 70. The diet was applied 6 days before (i.e., lead-in diet), and maintained during (5.1 g FODMAPs/day) the MSUM. Nutrition intake was analyzed through dietary analysis software. A validated 100-mm visual analog scale quantified GIS incidence and severity. GIS were modest during the MSUM (overall mean ± SD: bloating 27 ± 5 mm and flatulence 23 ± 8 mm), except severe nausea (67 ± 14 mm) experienced throughout. Total daily energy (11.7 ± 1.6 MJ/day) intake did not meet estimated energy requirements (range: 13.9–17.9 MJ/day). Total daily protein [1.4 ± 0.3 g·kg body weight (BW)−1·day−1], carbohydrate (9.1 ± 1.3 g·kg BW−1·day−1), fat (1.1 ± 0.2 g·kg BW−1·day−1), and water (78.7 ± 6.4 ml·kg BW−1·day−1) intakes satisfied current consensus guidelines, except for carbohydrates. Carbohydrate intake during running failed to meet recommendations (43 ± 9 g/hr). The runner successfully implemented a low-FODMAP diet and completed the MSUM with minimal GIS. However, suboptimal energy and carbohydrate intake occurred, potentially exacerbated by nausea associated with running at altitude.

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Probiotics in Irritable Bowel Syndrome: An Up-to-Date Systematic Review

Nutrients ◽

10.3390/nu11092048 ◽

2019 ◽

Vol 11 (9) ◽

pp. 2048 ◽

Cited By ~ 7

Author(s):

Hanna Fjeldheim Dale ◽

Stella Hellgren Rasmussen ◽

Özgün Ömer Asiller ◽

Gülen Arslan Lied

Keyword(s):

Systematic Review ◽

Irritable Bowel Syndrome ◽

Gut Microbiota ◽

Gastrointestinal Disorder ◽

Inclusion Criteria ◽

Probiotic Supplementation ◽

Beneficial Effects ◽

Randomized Controlled ◽

Irritable Bowel ◽

Gut Microbiota Composition

Irritable bowel syndrome (IBS) is a frequent functional gastrointestinal disorder, and alterations in the gut microbiota composition contributes to symptom generation. The exact mechanisms of probiotics in the human body are not fully understood, but probiotic supplements are thought to improve IBS symptoms through manipulation of the gut microbiota. The aim of this systematic review was to assess the latest randomized controlled trials (RCTs) evaluating the effect of probiotic supplementation on symptoms in IBS patients. A literature search was conducted in Medline (PubMed) until March 2019. RCTs published within the last five years evaluating effects of probiotic supplements on IBS symptoms were eligible. The search identified in total 35 studies, of which 11 met the inclusion criteria and were included in the systematic review. Seven studies (63.6%) reported that supplementation with probiotics in IBS patients significantly improved symptoms compared to placebo, whereas the remaining four studies (36.4%) did not report any significant improvement in symptoms after probiotic supplementation. Of note, three studies evaluated the effect of a mono-strain supplement, whereas the remaining eight trials used a multi-strain probiotic. Overall, the beneficial effects were more distinct in the trials using multi-strain supplements with an intervention of 8 weeks or more, suggesting that multi-strain probiotics supplemented over a period of time have the potential to improve IBS symptoms.

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