The Effect of Citrus Extract on Gastrointestinal Health

Study Overview
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Brief Summary
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This randomized, parallel, double-blind, placebo-controlled trial aims to determine the effects of daily administration of citrus extract over a period of 8 weeks on gastrointestinal health in patients with irritable bowel syndrome.

Official Title
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The Effect of Citrus Extract Administration on Gastrointestinal Health

Conditions
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Irritable Bowel Syndrome

Intervention / Treatment
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* Dietary Supplement: Citrus extract
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with IBS Calprotectin levels 15-150 µg/g feces Age 18-70 years BMI < 35 kg/m2 Exclusion Criteria: Comorbidities that may influence gut microbiota composition or which might limit participation in or completion of the study protocol (to be decided by the principle investigator) Abdominal surgery interfering with gastrointestinal function (to be decided by the principle investigator) Use of immunosuppressive drugs within 3 months before study period Use of other medication interfering with endpoints Changes in medication that may significantly affect the study outcome according to the investigator's judgment within 1 month prior to the study Changes in clinical activity scores within 3 weeks prior to the study Administration of investigational drugs or participation in any scientific intervention study which may interfere with this study (to be decided by the principle investigator) in the 180 days prior to the study Use of dietary supplements containing antioxidants, minerals and vitamins Excessive intake of foods with a high polyphenol concentration Use of antibiotics within 3 months prior to the start of study Use of pre-or probiotics within 1 month prior to the study Use of oral corticosteroids within 1 month prior to the study Blood donation within 1 month prior to the study Known pregnancy or lactation. Excessive drinking (>20 alcoholic consumptions per week) History of any side effects towards the intake of flavonoids or citrus fruits

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Citrus extract<br>Citrus extract | Dietary Supplement: Citrus extract<br>* Citrus extract<br>|
| Placebo Comparator: Placebo<br>Maltodextrin | Dietary Supplement: Placebo<br>* Maltodextrin<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The effect on intestinal inflammation, measured by fecal calprotectin levels. | The primary objective is to assess the effect of 500 mg citrus extract on intestinal flammation after 8 weeks of administration, by measuring fecal calprotectin in IBS patients with moderately increased fecal calprotectin levels. | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The effect on microbial metabolic activity, measured by fecal short chain fatty acids (SCFA). |  | 8 weeks | 
| The effect on fecal microbiota composition, assessed by next generation sequencing. |  | 8 weeks | 
| The effect on fecal microbiota functional capacity, assessed by next generation sequencing. |  | 8 weeks | 
| The effect on the systemic immune response, measured by cytokine production capacity of stimulated whole blood |  | 8 weeks | 
| The effect on disease symptoms, measured by patient reported outcomes (GSRS). |  | 8 weeks | 
| The effect on disease symptoms, measured by patient reported outcomes (symptom diary). |  | 8 weeks | 
| The effect on stool frequency, measured by Bristol Stool Chart. |  | 8 weeks | 
| The effect on stool consistency, measured by Bristol Stool Chart. |  | 8 weeks | 
| The effect on blood markers for oxidative stress, measured by MDA concentration in blood. |  | 8 weeks | 
| The effect on blood markers for antioxidant capacity, measured by blood total antioxidant capacity. |  | 8 weeks |