Biomarkers of Diet-microbiota Interactions in Irritable Bowel Syndrome

McMaster University

Status and phase: Enrolling; Early Phase 1

Conditions: Irritable Bowel Syndrome

Treatments: Other: Placebo; Dietary Supplement: High-FODMAP beverage; Dietary Supplement: Low-FODMAP beverage; Dietary Supplement: Lactobacillus acidophilus CL1285, L. casei LBC80R and L. rhamnosus CLR2.; Dietary Supplement: L-Histidine

Study type: Interventional

Funder types: Other

Identifiers

NCT04364750

BFIBS

Details and patient eligibility

About

Most patients suffering from the irritable bowel syndrome (IBS) report that ingestion of certain foods is a major trigger of symptoms, but the reason is unclear. Previous studies have shown that foods containing poorly absorbed carbohydrates (FODMAPs) are fermented by the bacteria in our bowels and these cause symptoms in some but not all patients. Gut bacteria are capable of producing various products, such as neuroimmune mediator histamine, that may be related to IBS symptoms. Our recent data suggest that consumption of FODMAPs promotes production of bacterial histamine.

The main objective of this study is to investigate bacterial production of histamine and its relationship to IBS symptoms. The study will involve 6 weeks on a low-FODMAP diet with three three-day interventions consisting of High- or Low-FODMAP drinks along with probiotics or placebo capsules. The patient's bacteria and metabolites will be analyzed at various time points.

Enrollment: 30 estimated patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Adults aged 18-75 with IBS (Rome IV criteria) who have self-reported previous improvement in their IBS symptoms while on a low FODMAP diet, or when excluding certain high-FODMAP foods, or patients in whom histamine is expected to play a key role (either diagnosed with high histamine producing bacteria, or improved IBS symptoms after using antihistamines). Individuals should be able to swallow size 00 capsules.

Exclusion criteria

• Concurrent significant organic GI pathology (i.e. celiac, IBD, etc.)
• Concurrent systemic disease (such as diabetes) and/or laboratory abnormalities considered by investigators to be risky or that could interfere with data collection
• History of active cancer in the last 5 years, other than basal cell cancer
• Pregnant or breastfeeding women
• Active or recent participation (< 1 month) in a clinical study, except for SPOR IMAGINE
• Use of antibiotics, probiotics, or ACE inhibitors during, or one month prior to the study
• Use of new medications less than 4 weeks prior to the study.
• Allergies to any of the ingredients used in the study
• Any immune-compromising conditions

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

---

30 participants in 3 patient groups

Group A

Experimental group

Description:

Participants in group A will undergo challenges in the order: 1. High-FODMAP beverage + placebo probiotic + L-Histidine 2. Low-FODMAP beverage + placebo probiotic + L-Histidine 3. High-FODMAP beverage + probiotic + L-Histidine Challenges each last 5 days, but the FODMAP drinks and the L-Histidine capsules are only taken for the last three days. There is a 10 day washout period between challenges.

Treatment:

Dietary Supplement: Lactobacillus acidophilus CL1285, L. casei LBC80R and L. rhamnosus CLR2.

Dietary Supplement: L-Histidine

Other: Placebo

Dietary Supplement: High-FODMAP beverage

Dietary Supplement: Low-FODMAP beverage

Group B

Experimental group

Description:

Participants in group A will undergo challenges in the order: 1. Low-FODMAP beverage + placebo probiotic + L-Histidine 2. High-FODMAP beverage + probiotic + L-Histidine 3. High-FODMAP beverage + placebo probiotic + L-Histidine. Challenges each last 5 days, but the FODMAP drinks and the L-Histidine capsules are only taken for the last three days. There is a 10 day washout period between challenges.

Treatment:

Dietary Supplement: Lactobacillus acidophilus CL1285, L. casei LBC80R and L. rhamnosus CLR2.

Dietary Supplement: L-Histidine

Other: Placebo

Dietary Supplement: High-FODMAP beverage

Dietary Supplement: Low-FODMAP beverage

Group C

Experimental group

Description:

Participants in group A will undergo challenges in the order: 1. High-FODMAP beverage + probiotic + L-Histidine 2. High-FODMAP beverage + placebo probiotic + L-Histidine 3. Low-FODMAP beverage + placebo probiotic + L-Histidine. Challenges each last 5 days, but the FODMAP drinks and the L-Histidine capsules are only taken for the last three days. There is a 10 day washout period between challenges.

Treatment:

Dietary Supplement: Lactobacillus acidophilus CL1285, L. casei LBC80R and L. rhamnosus CLR2.

Dietary Supplement: L-Histidine

Other: Placebo

Dietary Supplement: High-FODMAP beverage

Dietary Supplement: Low-FODMAP beverage