Gut-brain Axis, Brain Function, and Behaviour.

NCT03554694 | Unknown

• 1 other identifier: R52324_RE001
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The aim is to test if dietary supplementation with prebiotics reduces measures of anxiety in healthy human participants with high self-reported levels of anxiety. Study will test for an effect on behavioural, neuroendocrine and brain imaging markers of anxiety.

Conditions

Prebiotics; Anxiety; Humans; Magnetic Resonance Imaging; Decision Making; Emotion; Cortisol

Outcome Measures

Primary Outcomes (2)

• Cortisol awakening response (CAR)

  CAR, a marker of stress responsivity, should be decreased after taking prebiotics compared to placebo (as previously found in non-anxious participants in Schmidt et al., 2015, Psychopharmacology)

  Cortisol awakening responses will be measured at the end of the first intervention phase (4-6 weeks after study entry) and at the end of the second intervention phase (11-15 weeks post study entry).

• Brain imaging (BOLD fMRI activity) in amygdala and cortical regions

  Brain imaging (BOLD fMRI activity) in amygdala and cortical regions Will provide neural measures of threat reactivity. We predict decreased amygdala and/or increased parietal-prefrontal brain activity after prebiotics compared to placebo, indicating an anxiolytic-like profile (fearful -neutral face trials in the low load condition) (as in Bishop et al, 2007 and Ironside et al, 2017)

  Brain imaging will be measured at the end of the first intervention phase (4-6 weeks after study entry) and at the end of the second intervention phase (11-15 weeks post study entry).

Secondary Outcomes (1)

• Changes in gut microbiome

  Changes in the microbiome will be measure using a single stool/faecal sample at four time points: baseline (0 weeks), following first intervention (4-6 weeks), following washout (7-9 weeks), and following the second intervention (11-15 weeks).

Study Arms (2)

Start with prebiotics

EXPERIMENTAL

Half of the participants start with prebiotics, followed by a testing period. After a wash-out period they will continue with placebo followed by a testing period.

Dietary Supplement: Prebiotics

Start with placebo

EXPERIMENTAL

Half of the participants start with placebo, followed by a testing period. After a wash-out period they will continue with prebiotics followed by a testing period.

Dietary Supplement: Maltodextrin (placebo)

Interventions

Prebiotics DIETARY_SUPPLEMENT

Galactooligosaccharides (GOS) (prebiotics) will be consumed by the participants for 4-6 weeks

Start with prebiotics

Maltodextrin (placebo) DIETARY_SUPPLEMENT

Maltodextrin (placebo) will be consumed by the participants for 4-6 weeks

Start with placebo

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Trait anxiety levels \> 40 on STAI trait inventory
• Participant is willing and able to give informed consent for participation in the study
• Not currently taking any psychoactive medications

You may not qualify if:

• Pregnant participants
• No contraindications to prebiotic administration
• Antibiotic, probiotics and/or prebiotic treatment in at least the two previous months.
• Participants who are taking any other food supplements that, in the opinion of the Investigators, may affect the results.
• Participants who are taking any medications that, in the opinion of the Investigators, may affect the results.
• Any significant change in diet which, at the discretion of the Investigators, may affect the results.
• Participants who have recently participated in another research trial which, at the discretion of the Investigators, may affect the results.
• A history of dementia, traumatic brain injury or stroke.
• Anyone who is unable to perform the behavioural tasks.
• Current use of any psychoactive medication.
• Current use of psychological treatment.
• Anyone who does not have adequate understanding of English, sufficient to give informed consent.
• Any person who has a history of drug abuse or a previous history of a neurological, or has a history of neurosurgical procedure is excluded as they may be at increased risk of epilepsy and data collected may be influenced by their condition.
• Anyone with any metal implants or implantable device would be excluded from any brain imaging studies as indicated by the MRI safety screening form.

Sponsors & Collaborators

• University of Oxford: lead
• National Health and Medical Research Council, Australia: collaborator
• Oxford Health Biomedical Research Centre (OH BRC) support scheme: collaborator
• Wellcome Centre for Integrative Neuroimaging: collaborator
• Monash University: collaborator

Study Sites (1)

University of Oxford

Oxford, Oxfordshire, OX3 9DU, United Kingdom

RECRUITING

Related Publications (2)

• Schmidt K, Cowen PJ, Harmer CJ, Tzortzis G, Errington S, Burnet PW. Prebiotic intake reduces the waking cortisol response and alters emotional bias in healthy volunteers. Psychopharmacology (Berl). 2015 May;232(10):1793-801. doi: 10.1007/s00213-014-3810-0. Epub 2014 Dec 3.

  PMID: 25449699 BACKGROUND

• Bishop SJ, Jenkins R, Lawrence AD. Neural processing of fearful faces: effects of anxiety are gated by perceptual capacity limitations. Cereb Cortex. 2007 Jul;17(7):1595-603. doi: 10.1093/cercor/bhl070. Epub 2006 Sep 6.

  PMID: 16956980 BACKGROUND

MeSH Terms

Conditions

Anxiety Disorders

Interventions

Prebiotics; maltodextrin

Condition Hierarchy (Ancestors)

Mental Disorders

Intervention Hierarchy (Ancestors)

Dietary Fiber; Dietary Carbohydrates; Carbohydrates; Polysaccharides, Bacterial; Polysaccharides; Food; Diet, Food, and Nutrition; Physiological Phenomena; Dietary Supplements; Food and Beverages

Study Officials

• Jacinta O'Shea, PhD

  University of Oxford

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Gershon Spitz, PhD

CONTACT

+44 (0)1865611456; gershon.spitz@ndcn.ox.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Both intervention and placebo products are similar in colour, texture, and taste. A third party, independent of the daya-to-day research coordinator, will randomise treatments.
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Crossover Assignment Randomised Double-blind Cross-over design with 4-6 weeks of prebiotics intervention and 4-6 weeks of placebo intervention. The first intervention phase will be followed by a 3 week wash-out period prior to the second intervention phase.d.

Study Record Dates

• First Submitted: May 9, 2018
• First Posted: June 13, 2018
• Study Start: May 6, 2018
• Primary Completion: December 1, 2019
• Study Completion: December 1, 2019
• Last Updated: June 13, 2018

Record last verified: 2018-05

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)