The Role of Short Chain Fatty Acids in Microbiota-gut-brain Axis (SCFA-AP)

Catholic University (KU) of Leuven

Status: Completed

Conditions: Fear; Emotions; Stress

Treatments: Dietary Supplement: SCFA mixture

Study type: Interventional

Funder types: Other

Identifiers

NCT03688854

S60501

Details and patient eligibility

About

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.

Full 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.

Enrollment: 66 patients

Sex: Male

Ages: 20 to 40 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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66 participants in 3 patient groups, including a placebo group

Placebo

Placebo Comparator group

Description:

Placebo are capsules containing cellulose.

Treatment:

Dietary Supplement: SCFA mixture

SCFA mixture low dose

Experimental group

Description:

Encapsulated SCFA mixture in the ratio of 67:6:27 (acetate, propionate, butyrate) equivalent of 10 grams of fiber.

Treatment:

Dietary Supplement: SCFA mixture

SCFA mixture high dose

Experimental group

Description:

Encapsulated SCFA mixture in the ratio of 67:6:27 (acetate, propionate, butyrate) equivalent of 20 grams of fiber.

Treatment:

Dietary Supplement: SCFA mixture