Effects of Butyrate on Affective Processes

Effects of Butyrate on Affective Processes

The effects of butyrate on psychobiological processes are examined in a sample of healthy volunteers.

The study is an interventional triple-blind, placebo-controlled, parallel group design with 2 arms (placebo, butyrate). Healthy male participants adhere to a low-fiber diet for the duration of the study (11 days). At the baseline study visit, measurements are taken in the lab, including biological samples and psychophysiological measurements. Participants then consume placebo or butyrate for 1 week and revisit the lab on day 11 for a second measurement of the outcomes of interest. Specifically, we investigate the effect of colonic butyrate administration on affective processing, including stress sensitivity and fear-related processes (e.g. extinction learning). Volunteers also respond to questionnaires in relation to mood and GI symptoms, and provide biological samples (saliva, blood, and faecal samples) for analysis of cortisol levels, circulating short chain fatty acids and serum BDNF, and faecal SCFA, respectively.

Inclusion Criteria:

• Male participants
• Age range 20-40 years
• BMI range 18.5-25
• Dutch or English 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