The Impact of Cranberries On the Microbiome and the Brain in Healthy Ageing sTudy (COMBAT) (COMBAT)

The Impact of Cranberries on the Microbiome and the Brain in Healthy Ageing: A Feasibility Intervention

Tremendous progress has been made in characterizing the interactions between the central nervous system and the gastrointestinal tract. This concept of a gut-brain axis suggests that influencing bacteria in the gut is a promising approach for developing new ways of benefiting brain function. This is particularly relevant for an ageing population for which cognitive decline is a common symptom and can be an indicator for the development of neurodegenerative conditions such as dementia. There is good evidence already that nutrition can delay the development of cognitive decline in ageing, in particular for ageing-sensitive brain regions such as the medial temporal lobe, however this has been little explored for cranberry intake. Cranberries are high in plant-derived nutrients called polyphenols, which have been suggested to promote brain function and protect against disease-causing mechanisms. In the proposed project we will pioneer work to investigate the impact of cranberry intake on gut bacteria and how it relates to cognitive performance in ageing and associated regions in the brain.

This study is being conducted by Chief Investigators Dr David Vauzour and Prof Michael Hornberger at the University of East Anglia. Sixty participants (i.e. n=30 control and treatment groups) aged 50-80 years old, with no memory complaints will be recruited for this 12-week double-blind placebo-controlled parallel intervention of cranberry flavonoids. Freeze-dried cranberry or a matched placebo will be taken twice daily for the duration of the trial. Blood, urine and faecal samples will be collected for microbiome, DNA, biochemical and nutritional analysis. Participants will also undergo cognitive testing, as well as MRI scanning to detect changes in brain physiology.

Study Overview

• Status: Completed
• Conditions: Aging; Cognitive Decline
• Intervention / Treatment: Dietary supplement: Freeze-Dried Cranberry Powder; Dietary supplement: Placebo

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Norfolk
    • Norwich, Norfolk, United Kingdom, NR4 7UQ
      • University of East Anglia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 46 years to 76 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged between 50 and 80 years old.
• Willing and able to provide written informed consent.
• Fluent in written and spoken English.
• Normal or corrected to normal vision and hearing.
• Understands and is willing and able to comply with all study procedures.

Exclusion Criteria:

• Diagnosis of any form of dementia or significant neurological condition.
• Significant memory complaints.
• Past history or MRI evidence of brain damage, including significant trauma, stroke, learning difficulties or serious neurological disorder, including a loss of consciousness for more than 24 hours.
• Currently smoking or ceased smoking less than 6 months ago.
• Chronic fatigue syndrome, liver disease, diabetes mellitus, or gall bladder abnormalities.
• History of alcohol or drug dependency.
• Clinically diagnosed psychiatric disorder.
• Existing diagnosed gastrointestinal disorders likely to impact on absorption of flavonoids.
• Known allergy to the intervention supplement.
• Any significant medical condition likely to affect participation.
• Currently a participant or have been a participant in any other study involving an investigational product within the last 4 weeks.
• Uncontrolled hypertension (systolic blood pressure >140mmHg, diastolic blood pressure >90mmHg).
• Major cardiovascular event, such as myocardial infarction, within the last 12 months.
• On a stable prescription of blood pressure lowering medication or non-steroidal anti-inflammatory drugs. for fewer than 2 months.
• Prescribed anti-coagulant/blood thinning medication (eg. warfarin).
• Taking flavonoid containing supplements (and unwilling to cease intake during, and 1 month preceding the trial) or unwilling to maintain existing intake of other supplements.
• High flavonoid intake defined as > 15 portions of flavonoid rich foods per day
• Are currently taking medication or supplements which have a significant impact on the outcome measures.

In addition, any participants with claustrophobia will not be invited to participate in the neuroimaging component of the study. Likewise for metal implants, e.g. pacemaker that precludes MRI.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active Cranberry Study Food	Dietary supplement: Freeze-Dried Cranberry Powder; Freeze-dried cranberry powder (or matched placebo), approximating 500mg active flavonoids per day, taken twice daily for 12 weeks.
Placebo Comparator: Placebo Study Food	Dietary supplement: Placebo; Placebo food powder matched for taste, colour, energy and macronutrient content to the active cranberry powder.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gut microflora speciation and metabolism	Measured in faecal and serum samples.	12 weeks
Change in volumes of hippocampus and other key brain structures	Structural magnetic resonance imaging	12 weeks
Change in cerebrovascular blood flow	Measured using spectroscopy	12 weeks
Change in global cognition	Global cognition to be measured using the Addenbrooke's Cognitive Examination - III, from 0-100, with higher scores indicating better global cognitive performance.	12 weeks
Change in spatial navigation abilities	The Supermarket Test, with outcomes including accurate reporting of starting direction, and accurate indication of end position and direction.	12 weeks
Change in executive function and attention	Trail Making Test, with scores including time taken to complete and number of errors made.	12 weeks
Change in memory performance	The Rey Complex Figure Test, with outcomes including time taken to complete copy, accuracy out of a possible 36 of copy and accuracy out of 36 of 3-minute recall.	12 weeks
Change in spatial navigation abilities	SeaHero Quest Test, with outcomes including time taken to complete, accuracy of path taken and number of errors made.	12 weeks
Change in executive function and attention	Digit Span Backwards, scored out of a possible 14 for numbers recited backwards in the correct order.	12 Weeks
Change in presence of circulating inflammatory biomarkers (hs-CRP)	Blood samples analysed for presence of inflammatory cytokines	12 weeks
Change in circulating biomarkers of neuronal functioning and cognitive decline (BDNF)	Blood samples analysed for presence of circulating biomarkers of neural function	12 weeks
Change in circulating biomarkers of lipid metabolism (total-, HDL-, LDL-cholesterol)	Blood samples analysed for presence of circulating biomarkers of lipid metabolism	12 weeks
Change in circulating biomarkers of lipid metabolism (triglycerides)	Blood samples analysed for presence of circulating biomarkers of lipid metabolism	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in energy expenditure and sleep	Actigraphs to be used to measure changes in activity and sleep patterns of participants.	12 weeks
Genetics related to neurodegenerative disease	Blood samples to be analysed for genes associated with neurodegenerative disease and dementia (eg. C9ORF72, APOE-4)	Baseline
Biomarkers of gut permability and endotoxemia (LPS)	Blood serum/plasma samples to be analysed for presence of lipopolysaccharide (LPS) as a biomarker of gut permability and possible endotoxemia	12 weeks
Levels of sunlight exposure	Self-reported levels of daily sunlight exposure to be measured using a brief questionnaire	Baseline, Follow-up

Collaborators and Investigators

• Sponsor: University of East Anglia
• Collaborators: Clinical Research and Trials Unit (Norfolk & Norwich University Hospital, UK)
• Investigators: Principal Investigator: David Vauzour, PhD, University of East Anglia

Publications and helpful links

General Publications

• Flanagan E, Cameron D, Sobhan R, Wong C, Pontifex MG, Tosi N, Mena P, Del Rio D, Sami S, Narbad A, Muller M, Hornberger M, Vauzour D. Chronic Consumption of Cranberries (Vaccinium macrocarpon) for 12 Weeks Improves Episodic Memory and Regional Brain Perfusion in Healthy Older Adults: A Randomised, Placebo-Controlled, Parallel-Groups Feasibility Study. Front Nutr. 2022 May 19;9:849902. doi: 10.3389/fnut.2022.849902. eCollection 2022.

Study record dates

Study Major Dates

• Study Start (Actual): October 2, 2018
• Primary Completion (Actual): May 22, 2020
• Study Completion (Actual): May 22, 2020

Study Registration Dates

• First Submitted: June 15, 2018
• First Submitted That Met QC Criteria: September 18, 2018
• First Posted (Actual): September 20, 2018

Study Record Updates

• Last Update Posted (Actual): September 30, 2020
• Last Update Submitted That Met QC Criteria: September 29, 2020
• Last Verified: September 1, 2020

More Information

Terms related to this study

• Keywords: Microbiome; Ageing; Nutrition; Cognition; Flavonoids
• Additional Relevant MeSH Terms: Mental Disorders; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction
• Other Study ID Numbers: R204719

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No