Healthy Adults.
Conditions
Brief summary
This study was a controlled, cross-over, acute flavonoid intervention trial with younger and older adults. Subjects consumed a blueberry beverage during one visit and a control beverage on another. Cognitive function pre drink was assessed, blood and urine samples were taken as well as blood pressure and a measure of vascular reactivity. These outcome measures were taken at 2 and 5 hours post drink. It was predicted that the flavonoids in the blueberry drink would lead to improved performance on the cognitive tests and vascular reactivity measure compared to following the control drink. It was thought this could be due to increased vaso-dilation and improving blood flow to the brain which was investigated in an extension to the project where a sample of individuals underwent brain imaging in an MRI scanner pre and post a blueberry and a control drink.
Detailed description
The control drink was matched to the blueberry drink for other bioactive compounds which may have affected cognition, specifically sugars and vitamin C. Volunteers were healthy, not on any medication, without high blood pressure, high cholesterol, high BMI, diabetes or other medical conditions. Older adults were aged 61-75 years and younger adults 18-26 years. Blood and urine samples will be analysed for flavonoid levels and Brain Derived Neurotrophic Factor, a biomarker of memory and learning, flavonoids may lead to increased BDNF production through the ERK-CREB-BDNF pathway. Flavonoids may also increase nitric oxide production and improve the flexibility of the blood vessels hence the measure of vascular reactivity using the Digital Volume Pulse machine. This can lead to increased vaso-dilation and blood flow to the brain, therefore an fMRI study was carried out the investigate this using arterial spin labeling following acute blueberry supplementation compared to a control drink.
Interventions
DIETARY_SUPPLEMENTFlavonoids
475g of anthocyanidins in 300ml of blueberry drink.
DIETARY_SUPPLEMENTControl
29g powder: sugars (glucose, sucrose, fructose), vitamin C and citric acid.
Sponsors
University of Reading
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
* No medical conditions * Not taking any medication or supplements (or willing to stop taking supplements for duration of study) * Not lactose intolerant * Willing to give blood and urine samples * Not partaking in frequent vigorous exercise * Not suffering from or history of depression
Exclusion criteria
* On blood pressure medication, taking Aspirin or other blood thinning medication * BMI \> 30 * Cholesterol \> 6 * Diabetes or other serious medical condition * Lactose intolerant * Any learning difficulty e.g. dyslexia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cognitive function | pre drink, 2 hours and 5 hours post drink | Extensive cognitive test battery including tasks measuring executive function such as updating, and memory tests such as free recall. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Bioavailability and pharmacology | Pre drink and 1 hour post drink | Flavonoid and BDNF levels in plasma and urine samples. |
| Vascular Reactivity | Pre and 1 hour post drink | Measurements taken using Digital volume pulse equipment. Blood pressure also recorded. |
| Neuronal effects | Pre and 1 hours post drink | Using fMRI to determine whether flavonoid supplementation leads to greater activation in brain regions associated with the cognitive abilities tested and to calculate cerebral blood flow before and after the blueberry compared to the control drink. |
Countries
United Kingdom
Outcome results
None listed