Clinical trial NCT03688854: The Role of Short Chain Fatty Acids in Microbiota-gut-brain Axis
Official title: Effects of Short Chain Fatty Acids on Affective Processes in Humans
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Emotions
Stress
Fear
Lead sponsor: KU Leuven
Sponsor class: OTHER
First posted: 2018-09-28
Enrollment: 66
Sex: MALE
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The role of short chain fatty acids (SCFA) in the microbiota-gut-brain axis is examined in a sample of healthy volunteers. SCFA are the major products of bacterial fermentation of dietary fiber in the colon, and are hypothesised to mediate the bidrectional communication between the gut and the residing microbiota on the one hand, and the central nervous system on the other hand. We perform a 1-week intervention with SCFA and measure their effects on a range of affective outcomes in healthy male volunteers.

Detailed description: The study is an interventional double-blind, placebo-controlled, parallel group design with 3 arms (placebo, high-dose of SCFA, and low-dose of SCFA). The high and low doses of SCFA are equivalent to 20 and 10 grams of fiber respectively. Healthy male participants follow a low-fiber diet for the study duration (11 days). On day 4, baseline measurements are taken in the lab, including biological samples and psychophysiological measurements. Participants then consume placebo or SCFA for one week and revisit the lab on day 11 for a second measurement of the outcomes of interest. Specifically, we investigate the effect of SCFA supplementation on affective processing, including stress sensitivity, fear-related processes (e.g. extinction learning), and attentional bias to emotional stimuli. Volunteers also respond to questionnaires in relation to mood, and provide biological samples (blood and faecal samples) for analysis of circulating short chain fatty acids and microbiota composition, respectively.

Eligibility criteria: Inclusion Criteria:

* Male participants
* Age range 20-40 years
* BMI range 18.5-27
* Dutch as native-language

Exclusion Criteria:

* previous or current neurological, psychiatric, gastrointestinal or endocrine disorders, or other relevant medical history
* current or recent regular medication use
* previous or current substance/alcohol dependence or abuse (\> 2 units per day/14 units per week)
* one or more diagnoses based on the mini-international neuropsychiatric interview
* smoking
* night-shift work
* adherence to vegan or vegetarian diets
* use of pre- or probiotics within one month preceding the study
* use of antibiotics within 3 months preceding the study
* previous experience with one of the tasks used in the study

Primary outcomes:
measure: Stress sensitivity
timeFrame: 1 year
Secondary outcomes:
measure: Stress sensitivity (subjective)
timeFrame: 1 year
measure: Cortisol awakening response
timeFrame: 1 year
measure: Fear
timeFrame: 1 year
measure: Fear (subjective)
timeFrame: 1 year
measure: Attentional bias to emotional stimuli
timeFrame: 1 year
measure: Perceived Stress Scale (PSS)
timeFrame: 1 year
measure: Positive and Negative Affect Schedule (PANAS)
timeFrame: 1 year
measure: Depression, Anxiety, and Stress Scale (DASS-21)
timeFrame: 1 year
measure: Gastointestinal symptom rating scale (GSRS)
timeFrame: 1 year
measure: Microbiota composition
timeFrame: 1 year
measure: Circulating SCFA
timeFrame: 1 year
Other outcomes:
Locations:
city: Leuven
country: Belgium
facility: UZ Leuven/Stresslab
Study officials:
affiliation: KU Leuven
name: Kristin Verbeke, Prof
role: PRINCIPAL_INVESTIGATOR
References: