Modulation of Intestinal Barrier Function and Inflammation Via Butyrate-promoting Dietary Fibre

Study Overview
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Brief Summary
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This study examines how a fermentable dietary fibre known to promote butyrate production impacts intestinal barrier function, intestinal microbiota, intestinal inflammation, and gastrointestinal symptoms in patients with microscopic colitis.

Detailed Description
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The study examines the effects of a 6-week supplementation period with a dietary fibre product (type of wheat bran) on intestinal barrier function, intestinal inflammation, intestinal microbiota, and gastrointestinal symptoms in patients with MC. The study subjects will consume the study products (placebo-fibre, butyrate-promoting fibre) as a powder supplemented to their daily habitual diet. A maltodextrin-based product is used as placebo. After giving their informed consent, the study subjects fill out a background questionnaire to assess their eligibility for the study (Visit 1). Participants deemed suitable for the study will be randomised into two study arms (placebo-fibre, butyrate-promoting fibre) before undergoing a baseline visit (Visit 2) before the start of the intervention period. After the 6-week intervention period, the participants will come back for a final visit (Visit 3). In vivo intestinal permeability will be measured using the standard multi-sugar test at visits 2 and 3. Blood and faecal samples will also be collected during visits 2 and 3. In addition to the visits described above, a subset of patients (max. 20) will undergo a colonoscopy before and at the end of the intervention period at Örebro University Hospital where an experienced gastroenterologist collects 16 colonic biopsies. These colonic biopsies are mounted in an Ussing chamber system to specifically study colonic permeability. During visits 2 and 3, the participants also complete questionnaires to assess their gastrointestinal symptoms, quality of life, physical activity, and dietary habits. During the study period, the participants will also keep a daily diary recording the number of diarrheal and loose stools. The participants are asked to maintain their habitual diet and lifestyle as well as not to consume probiotic or prebiotic supplements.

Official Title
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The Effects of Fermentable Dietary Fibre Supplementation on Intestinal Permeability and Inflammation in Microscopic Colitis

Conditions
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Microscopic Colitis

Intervention / Treatment
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* Dietary Supplement: Dietary fibre
* Dietary Supplement: Placebo compound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed informed consent Diagnosis of microscopic colitis (collagenous or lymphocytic colitis) Active disease with no medication (e.g. budesonide) or stable budesonide treatment with or without symptoms Age between 18-75 Exclusion Criteria: Previous diagnosis of other organic gastrointestinal disease that interferes with the outcome parameters used in this study (e.g. ulcerative colitis) Previous abdominal surgery which might influence gastrointestinal function, except appendectomy and cholecystectomy History of or present gastrointestinal malignancy or polyposis Diagnosis of gastrointestinal infection within the last 6 months Current diagnosis of dementia, severe depression, major psychiatric disorder, or other incapacity for adequate cooperation Chronic neurological/neurodegenerative disease (e.g. Parkinson's disease) Autoimmune disease (e.g. rheumatoid arthritis) Chronic pain syndromes (e.g. fibromyalgia) Chronic fatigue syndrome Severe endometriosis Coeliac disease Diagnosis of lactose intolerance within the last 3 months Pregnancy or breast-feeding Regular intake of anti-inflammatory and/or other immunosuppressive medication than budesonide within the last 3 months Intake of proton pump inhibitors (e.g. omeprazol) within the last 4 weeks Use of anti-depressants within the last 3 months Regular intake of mast cell stabilizing drugs (e.g. sodium cromoglycate) within the last 3 months Antimicrobial treatment within the last 12 weeks before baseline sampling Antimicrobial prophylaxis (e.g. urinary tract infection) Regular intake of probiotics, nutritional supplements, or herb products that might affect intestinal function within the last 4 weeks if the investigator considers that those could affect study outcome Inability to maintain current diet and lifestyle during the study period Alcohol or drug abuse Any clinically significant present or past disease/condition which the investigator considers to possibly interfere with the study outcome

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Dietary fibre<br>Butyrate-promoting dietary fibre | Dietary Supplement: Dietary fibre<br>* Dietary fibre as a powder, 24 g per day for 6 weeks<br>|
| Placebo Comparator: Placebo compound<br>Placebo compound | Dietary Supplement: Placebo compound<br>* Maltodextrin powder, 24 g per day for 6 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Colonic permeability in vivo | Difference in urinary sucralose/erythritol excretion ratio between the study arms | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Small intestinal permeability in vivo | Difference in urinary lactulose/rhamnose excretion ratio between the study arms | 6 weeks | 
| Colonic permeability ex vivo in Ussing chambers | Difference in the translocation of FITC-labeled dextran and horseradish peroxidase between the study arms | 6 weeks | 
| Concentrations of intestinal fatty-acid binding protein | Difference in plasma concentrations of intestinal fatty-acid binding protein between the study arms | 6 weeks | 
| Concentrations of lipopolysaccharide-binding protein | Difference in plasma levels of lipopolysaccharide-binding protein between the study arms | 6 weeks | 
| Concentratios of faecal calprotectin | Difference in faecal levels of calprotectin between the study arms | 6 weeks | 
| Concentrations of faecal myeloperoxidase | Difference in faecal levels of myeloperoxidase between the study arms | 6 weeks | 
| Concentrations of high-sensitive C-reactive protein | Difference in plasma levels of high-sensitive C-reactive protein between the study arms | 6 weeks | 
| Concentrations of inflammatory cytokines | Difference in TNF-a, IFN-y, IL-1B, IL-4, IL-6, IL-8, IL-10 levels in serum between the study arms | 6 weeks | 
| Composition of intestinal microbiota | Difference in the composition of intestinal microbiota between the study arms | 6 weeks | 
| Functionality of intestinal microbiota | Difference in the levels of intestinal microbiota -derived metabolites in the serum and faeces between the study arms | 6 weeks |