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Development of Non-invasive Methods to Study Gut Microbiome - Nutrition - Host Interactions

Not Applicable
Recruiting
Conditions
Healthy
Interventions
Other: Administration of standardized meals with characterized dietary fiber content
Other: Lactulose test
Other: Screening visit
Registration Number
NCT05949411
Lead Sponsor
Université Catholique de Louvain
Brief Summary

The aim of this study is to develop and validate an adequate protocol of volatolome (volatile metabolites) measurement in breath of human volunteers (18-65 years) to study gut microbiome - nutrition - host interactions in a general healthy population. For this purpose, breath volatile metabolites (BVM) will be analyzed throughout test days in fasting state and after standardized meals using selected ion flow tube mass spectrometry (SIFT-MS). In addition, gut microbial functions linked notably to hydrogen/methane production, carbohydrates utilization (CAZymes), and in the production of other volatile metabolites of interest (i.e. indole, fatty acid derivatives, ...) will be unraveled through microbiome sequencing data analysis (in silico), metabolomic analyses and measurement of enzymatic activities from saliva, urine and/or fecal samples.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
100
Inclusion Criteria
  • Woman or man, aged of 18 to 65 years;
  • Body mass index (BMI) between 18 and 30 kg/m2;
  • Non-smoker;
  • Provision of signed and dated informed consent form;
  • Stated willingness to comply with all study procedures and availability for the duration of the study;
  • Speaking French.
Exclusion Criteria
  • Subject with severe systemic disease (renal or hepatic failure, cancer, pancreatic cancer, chronic pancreatitis, asthma ...)
  • Subject with a history or current chronic/severe gastrointestinal disorder such as duodenal ulcer, chronic colitis, or chronic inflammatory disease of the digestive tract disease (Crohn's disease, ulcerative colitis), celiac disease or irritable bowel syndrome;
  • Subjects with a history of digestive tract surgery (except appendectomy);
  • Subject who had surgery within the two months prior to the study
  • Subjects with psychiatric problems and/or using antipsychotics
  • Current or recent (< 4 weeks) intake of antibiotics, fiber supplement, and/or any products modulating gut transit (laxative, anti-diarrheal, ...) or gut microbiota composition; these products will also be avoided for the duration of the study;
  • Chronic intake of drugs, except contraceptive drug;
  • Subject following a low-calorie diet and followed by a doctor or dietician in progress or recently (< 6 weeks);
  • Women of childbearing age who are pregnant or breastfeeding or who wish to become pregnant within the next 6 weeks or who are not using an adequate method of contraception (e.g. oral contraception, intrauterine device (IUD), abstinence, ...);
  • Subjects who drink more than 3 glasses of alcohol per day (> 30 g of alcohol per day);
  • Subjects having participated to another clinical trial two weeks before the screening test visit;
  • Subjects who practice an intense sport activity (more than 10 hours per week of intense activity);
  • Language barrier, mental or legal incapacity, unwillingness or inability to understand or not being able to participate to the study.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Meal 2Administration of standardized meals with characterized dietary fiber contentD16+/-7
LactuloseLactulose testD0
ScreeningScreening visitD-42 to D-7
Meal 3Administration of standardized meals with characterized dietary fiber contentD18+/-7
Meal 1Administration of standardized meals with characterized dietary fiber contentD14+/-7
Primary Outcome Measures
NameTimeMethod
Exhaled volatile compoundsThroughout the entire study, approximately during 24 months

Selected Ion flow tube mass spectrometry (SIFT-MS) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Secondary Outcome Measures
NameTimeMethod
Gastrointestinal symptom - discomfortThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Exhaled hydrogen (H2)Throughout the entire study, approximately during 24 months

Lactotest 202 - Area under the curve (calculated on 4 hours following lactulose ingestion)

Well-beingThroughout the entire study, approximately during 24 months

The short form (36) health survey (SF36) (0 = worse physical and mental health functioning, 100 = best physical and mental health functioning)

Gut microbiotaThroughout the entire study, approximately during 24 months

Illumina sequencing of 16S ribosomal deoxyribonucleic acid (rDNA), quantitative polymerase chain reaction (PCR)

Exhaled methane (CH4)Throughout the entire study, approximately during 24 months

Lactotest 202 - Area under the curve (calculated on 8 hours following breakfast ingestion)

Carbohydrates utilization - Carbohydrate active enzymes (CAZymes)Throughout the entire study, approximately during 24 months

Saliva enzymatic activities

Gastrointestinal symptom - nauseaThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Gastrointestinal symptom - gastrointestinal refluxThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Gastrointestinal symptom - crampsThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Transit - frequencyThroughout the entire study, approximately during 24 months

Questionnaire on stool frequency (record each defecation time)

Salivary microbiotaThroughout the entire study, approximately during 24 months

Illumina sequencing of 16SrDNA, quantitative PCR

Gastrointestinal symptom - bloatingThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Gut microbiota metabolic capacityThroughout the entire study, approximately during 24 months

Enzymatic analysis via in-vitro studies, incubation of fecal extracts

Nutrient intakeThroughout the entire study, approximately during 24 months

Food diary (daily log of what the volunteer eats and drinks each day)

Transit - ease of passageThroughout the entire study, approximately during 24 months

5-point Likert's scale (1 = very difficult to defecate, 5 = very easy to defecate)

Transit - level of emergencyThroughout the entire study, approximately during 24 months

5-point Likert's scale (1 = very urgent need to defecate, 5 = very nonurgent need to defecate)

Transit - empty feelingThroughout the entire study, approximately during 24 months

5-point Likert's scale (1 = very nonempty feeling after defecation, 5 = very empty feeling after defecation)

Gastrointestinal symptom - flatulencesThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Gastrointestinal symptom - rumblingThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom) - Area under the curve (calculated on 8 hours following breakfast ingestion)

Gastrointestinal symptom - burpsThroughout the entire study, approximately during 24 months

100 mm Visual analog scale (0 = no symptom, 100 = very severe symptom)

Exhaled carbon dioxide (CO2)Throughout the entire study, approximately during 24 months

Lactotest 202 - Area under the curve (calculated on 4 hours following lactulose ingestion)

Dietary habitsThroughout the entire study, approximately during 24 months

Food frequency questionnaire (FFQ) (record the volunteers' usual diet and dietary habits)

Transit - type of stoolThroughout the entire study, approximately during 24 months

Bristol stools scale (BSS) (classify the form of feces into 7 categories; type 1 = severe constipation, type 2 = mild constipation, types 3 and 4 = normal, type 5 = lacking fiber, type 6 = mild diarrhea, type 7 = severe diarrhea)

Trial Locations

Locations (3)

Metabolism and Nutrition research group (MNUT), Louvain Drug Research Institute (LDRI), UCLouvain

🇧🇪

Woluwe-Saint-Lambert, Brussels, Belgium

Center of Investigation in Clinical Nutrition (CICN), UCLouvain/CICN

🇧🇪

Ottignies-Louvain-la-Neuve, Brabant Wallon, Belgium

Testing rooms of Institute of Neuroscience (IONS), UCLouvain/IONS

🇧🇪

Woluwe-Saint-Lambert, Brussels, Belgium

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