Elucidating the Influence of Lactulose Intake on the Gut Microbiota Composition

Study Overview
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Brief Summary
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This study will test the influence of lactulose of the human gut microbiota. Healthy volunteers will ingest 50g of lactulose and donate stool samples 1 day before as well as 1-2 days and 14 days after the test. Using sequencing and metabolomics techniques the investigators will identify changes in microbiota composition upon lactulose exposure.

Detailed Description
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This is a clinical study for investigating the influence of lactulose on the composition and metabolic activities of the intestinal microbiota. We will recruit 40 healthy volunteers. Subjects will be randomized and receive either 50g lactose (intervention group) or 50g sucrose (control group). Subjects will donate fecal samples 24h before and after (1-2d, 14d) lactulose ingestion. After ingestion H2-in expiratory air and symptoms will be followed for 3 hours. Frozen samples will be analyzed for their microbiota composition and key metabolites.

Official Title
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Elucidating the Influence of Lactulose Intake on the Gut Microbiota Composition

Conditions
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Changes in Gut Microbiota Composition After Lactulose Exposure

Intervention / Treatment
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* Drug: application of lactulose
* Other: application of sucrose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects free of relevant abdominal complaints (=healthy) Written informed consent Working at ETH Zurich/University of Zurich, experience in handling of -80°C freezers on biosafety level 2 Exclusion Criteria: Previous history of gastrointestinal disease or surgery (excludes appendectomy, hernia repair and anorectal disorders) Known diabetes mellitus, scleroderma, neurological impairment or other major current disease Subjects unable to stop medication that alters gut flora: proton pump inhibitors, laxatives and antibiotics at least 4 weeks before study entry. Pregnancy beyond week 12 (no pregnancy test will be performed) Involvement in any other clinical trial during the course of this trial, nor within a period of 14 days prior to its beginning or 14 days after its completion

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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 |
| --- | --- |
| Experimental: Lactulose group<br>Subjects will ingest 50g of lactulose once | Drug: application of lactulose<br>* Subjects will ingest 50g of lactulose once<br>|
| Placebo Comparator: Control group<br>Subjects will ingest 50g of sucrose once | Other: application of sucrose<br>* Subjects will ingest 50g of sucrose once<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of lactulose intake on gut microbiota composition (microbiota sequencing, analysis of E. coli) | microbiota sequencing, analysis of E. coli | 1-2 days after ingestion of lactulose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of lactulose intake on metabolic profiles within the fecal ecoystem (metabolomics analysis) | metabolomics analysis | 1-2 days after ingestion of lactulose | 
| Correlation of gut microbiota composition and H2-peak (H2-measurements) | H2-measurements | within 3 hours after lactulose ingestion | 
| Correlation of gut microbiota composition and symptoms (standardized record of symptoms) | standardized record of symptoms | within 3 hours after lactulose ingestion |