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Trial registered on ANZCTR


Registration number
ACTRN12622000850774
Ethics application status
Approved
Date submitted
2/06/2022
Date registered
16/06/2022
Date last updated
16/06/2022
Date data sharing statement initially provided
16/06/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Polyphenol-rich drink for gut and brain health
Scientific title
The effects of a polyphenol-rich blackcurrant drink on markers of the gut-brain axis in healthy females: A randomised double-blind cross-over intervention trial.
Secondary ID [1] 307270 0
None
Universal Trial Number (UTN)
U1111-1276-9066
Trial acronym
LINK study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Neurocognitive disturbances 326526 0
Gastrointestinal dysbiosis 326527 0
Condition category
Condition code
Diet and Nutrition 323790 323790 0 0
Other diet and nutrition disorders
Mental Health 323791 323791 0 0
Studies of normal psychology, cognitive function and behaviour
Oral and Gastrointestinal 323792 323792 0 0
Normal oral and gastrointestinal development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
300mL of Arepa performance drink (blackcurrant-based, polyphenol-rich beverage available on the market containing approximately 300mg of anthocyanins, 200mg of L-theanine, and 150mg of Enzogenol) or a taste- and colour-matched 300mL placebo.

Participants will consume one beverage (intervention or placebo) once daily for 4 weeks, and after a 4-week wash-out period the participants will cross over and receive the other treatment. Participants will be instructed to consume the drink every day at any time of day.

Adherence will be monitored through a weekly self-report diary.
Intervention code [1] 323706 0
Prevention
Comparator / control treatment
The placebo beverage is matched for taste, colour, and macronutrient composition to the Arepa performance drink, but does not contain anthocyanins, L-theanine, or Enzogenol
Control group
Placebo

Outcomes
Primary outcome [1] 331558 0
Change in stress reactivity to a multi-tasking cognitive stressor (purple multi-tasking framework), measured by Bond-Lader visual analogue mood scales and the State-Trait Anxiety Inventory (State subscale). This is reported as a composite measure.
Timepoint [1] 331558 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [1] 410266 0
Faecal gut microbiota (composition and predicted function), measured by shotgun metagenome sequencing.
Timepoint [1] 410266 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [2] 410267 0
Change in cognitive performance, measured by the purple multi-tasking framework
Timepoint [2] 410267 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [3] 410268 0
Change in sleep quality, measured by the Pittsburgh Sleep Quality Index
Timepoint [3] 410268 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [4] 410269 0
Change in platelet MAO-B activity, measured in a blood sample
Timepoint [4] 410269 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [5] 410270 0
Change in circulating tryptophan metabolite concentrations, measured in a blood sample
Timepoint [5] 410270 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [6] 410271 0
Change in circulating inflammatory marker concentrations (interleukin-6), measured in a blood sample
Timepoint [6] 410271 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.
Secondary outcome [7] 410272 0
Change in mood, measured by the profile of mood state questionnaires
Timepoint [7] 410272 0
Baseline and 4 weeks post-intervention commencement, and baseline and 4 weeks post-placebo commencement.

Eligibility
Key inclusion criteria
• Females aged between 18-45 years.
• BMI between 18-30 kg/m2.
• Not pregnant, nor intending to become pregnant during the trial.
• Has access to internet and a computer, smart phone, or tablet.
• Agree not to enroll in another interventional clinical research trial 4 weeks prior to and for the duration of the study period
• Understands, and is willing and able to comply with all study procedures
• Willing and able to provide written informed consent
Minimum age
18 Years
Maximum age
45 Years
Sex
Females
Can healthy volunteers participate?
Yes
Key exclusion criteria
• Treated for anxiety, depression, or psychiatric disorders within the past two years.
• Diagnosed with gastrointestinal disorders (Coeliac disease, ulcerative colitis, Crohn’s disease), or had past major gastrointestinal surgery likely to interfere with study outcomes (e.g., hemi colectomy, ileostomy, colostomy).
• History of neurological disorders (e.g., Epilepsy, Parkinson’s Disease, stroke, serious head trauma), cognitive impairment, cardiovascular diseases or diabetes requiring medication.
• Medication use expected to interfere with normal digestive processes, including proton pump inhibitors, laxatives.
• Antibiotic use in the four weeks prior to the intervention.
• Prebiotic or probiotic supplement use and are not willing to cease intake for four weeks prior to (and duration of) the intervention.
• Herbal extract supplement use expected to interfere with cognition or mood and are not willing to cease use for four weeks prior to (and duration of) the intervention.
• Self-reported alcohol intake exceeding a moderate intake (>15 standard drinks/week).
• Regular use of recreational/illicit drugs
• Sensitivity to the investigational product, or any of the active/inactive ingredients.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is concealed through central randomisation by computer.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation sequences will be generated on a 1:1 allocation ratio. An unblinded researcher will use a computer-generated randomisation programme to generate a randomisation table using random block sizes, which will be partitioned by two strata based on participant’s diet quality at baseline (“optimal” or “suboptimal”).

Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
A sample size of 40 subjects was calculated based on reported changes in stress following four weeks of intervention with equivalent doses of constituent bio-actives in the Arepa performance drink. A sample size of 35 subjects is estimated to be adequate for a between-group difference of 20% to identify significant differences at a level of 5%. A sample size of 40 will allow for a drop-out rate not exceeding 15%.



Differences in neurocognitive and biochemical markers between treatment groups will be compared using two-way repeated measures ANOVA or non-parametric tests, followed by post-hoc analysis. Differences in markers of the gut microbiota between treatment groups will be evaluated by Kruskal-Wallis and PERMANOVA tests. The relationship between primary and secondary endpoints will be assessed using correlation and multiple regression analyses.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 24813 0
New Zealand
State/province [1] 24813 0
Auckland

Funding & Sponsors
Funding source category [1] 311568 0
Government body
Name [1] 311568 0
New Zealand Ministry of Business Innovation and Employment
Country [1] 311568 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
85 Park Road
Grafton
Auckland, 1023
Country
New Zealand
Secondary sponsor category [1] 312986 0
None
Name [1] 312986 0
NA
Address [1] 312986 0
NA
Country [1] 312986 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311016 0
Central Health and Disability Ethics Committees
Ethics committee address [1] 311016 0
Ministry of Health
Health and Disability Ethics Committees
133 Molesworth Street, Thorndon
Wellington 6011
Ethics committee country [1] 311016 0
New Zealand
Date submitted for ethics approval [1] 311016 0
27/04/2022
Approval date [1] 311016 0
27/05/2022
Ethics approval number [1] 311016 0
2022 EXP 12513

Summary
Brief summary
There is growing awareness that gut health is linked to virtually all aspects of human health, from digestive function to metabolic health, immunity, cognition, and mental wellbeing. At the same time, the prevalence of functional gut disorders is on the rise, thought to result from disturbances to the gut-brain axis.

The Arepa formula has the potential to provide additive benefits along the gut-brain axis. The Neuroberry® blackcurrant cultivar used in the Arepa formula is unique to Aotearoa and is particularly rich in anthocyanins. Anthocyanins are thought to have a proliferative effect on ‘good’ gut bacteria, yet research in humans has been limited to date. Other plant-derived bio-actives in the Arepa formula are known to target stress, anxiety, cognition, and sleep – all of which can have beneficial effects on the gut microbiota and vice versa.

A systems approach will be used in this research, providing insight into links between the gut microbiome, blood markers, neurocognitive responses, and diet. The researchers aim to determine whether daily consumption of the Arepa performance beverage has a prebiotic effect, improving the gut microbiota composition and its predicted function. This research also aims to tease apart the role of the gut microbiota in mediating the known neurocognitive benefits of Arepa.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 119706 0
Dr Nicola Gillies
Address 119706 0
Nutrition Department
Faculty of Medical and Health Sciences, University of Auckland
85 Park Road
Grafton
Auckland, 1023
Country 119706 0
New Zealand
Phone 119706 0
+64 220878065
Fax 119706 0
Email 119706 0
Contact person for public queries
Name 119707 0
Dr Nicola Gillies
Address 119707 0
Nutrition Department
Faculty of Medical and Health Sciences, University of Auckland
85 Park Road
Grafton
Auckland, 1023
Country 119707 0
New Zealand
Phone 119707 0
+64 220878065
Fax 119707 0
Email 119707 0
Contact person for scientific queries
Name 119708 0
Dr Nicola Gillies
Address 119708 0
Nutrition Department
Faculty of Medical and Health Sciences, University of Auckland
85 Park Road
Grafton
Auckland, 1023
Country 119708 0
New Zealand
Phone 119708 0
+64 220878065
Fax 119708 0
Email 119708 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
All individual participant data (including data dictionaries) collected during the trial will be available after de-identification, along with the study protocol.
When will data be available (start and end dates)?
Data will be available beginning 3 months following the first publication of study results and ending 36 months following publication.
Available to whom?
Data will be available to investigators who provide a methodologically sound proposal approved by the study Steering Committee, for use to achieve the aims in the approved proposal. Proposals should be directed to the principle investigator. To gain access, requests will need to sign a data access agreement
Available for what types of analyses?
For use to achieve the aims in an approved proposal.
How or where can data be obtained?
Proposals should be directed to the principle investigator ([email protected]). To gain access, requests will need to sign a data access agreement.


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
16276Study protocol  [email protected]
16277Informed consent form  [email protected]
16278Ethical approval  [email protected]



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.