Clinical trial NCT04374409: Effects of Acute Intake of Flavanols on Cerebral Oxygenation and Cognition in Young Male Adults
Official title: A Placebo-controlled, Randomized, Double-masked, Cross-over Acute Intervention Study Investigating the Effects of Flavanols on Cerebral Oxygenation and Cognition in Young Adults
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: flavanol
cocoa
brain
oxygenation
vascular
cognition
hypercapnia
functional near-infrared spectroscopy
Lead sponsor: University of Birmingham
Sponsor class: OTHER
Collaborators: name: University of Illinois at Urbana-Champaign
First posted: 2020-05-05
Enrollment: 18
Sex: MALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: The study evaluates the impact of one acute dose of cocoa flavanols on brain oxygenation during a hypercapnia challenge, as well as impact on cognitive performance in young healthy males. It further assesses the impact of flavanols on peripheral vascular function, as measured by brachial Flow-mediated dilation (FMD). All participants received a high-flavanol cocoa intervention (185.5 mg of flavanols (-)-epicatechin and (+)- catechin) and a low-flavanol cocoa intervention (\< 4 mg of flavanols). It is hypothesized that the high-flavanol intervention increases cerebral oxygenation during hypercapnia and vascular function in comparison to the low-flavanol intervention.

Detailed description: Cocoa flavanols have been shown to be protective against vascular disease in humans, as evidenced by improvements in peripheral endothelial function (as measured by brachial Flow-mediated dilatation, FMD). There is also emerging evidence suggesting that flavanol-rich diets protect against cognitive aging, but mechanisms remain elusive. In this study the investigators suggest that such mechanisms might be associated with benefits within the brain vasculature. The aim of the present study was therefore to determine whether intake of flavanols enhances cerebral oxygenation in frontal cortical areas of the brain during a hypercapnia challenge (which is a well-established biomarker of vascular reactivity in the brain) to a greater extent than a low-flavanol intervention in young healthy adults.

Eligibility criteria: Inclusion Criteria:

* Male
* 18-45 years old

Exclusion Criteria:

* smokers
* hypertensive
* with history of cerebrovascular, cardiovascular or respiratory disease
* allergies or intolerances to ingredients present in cocoa powders
* taking long-term medication (e.g., hyperlipidaemia)
* on antibiotics for the previous 3 months before enrollment
* suffering from blood-clotting disorders
* known infections at the time of the study
* on a weight-reducing regimen

Primary outcomes:
measure: Cortical Blood Oxygenation reactivity to hypercapnia using functional near-infrared spectroscopy (fNIRS)
timeFrame: Change from baseline to 2 hours
measure: Time to reach 90% of maximum cortical blood oxygenation during hypercapnia using functional near-infrared spectroscopy (fNIRS)
timeFrame: Change from baseline to 2 hours
Secondary outcomes:
measure: Cortical Blood Deoxygenation reactivity to hypercapnia using functional near-infrared spectroscopy (fNIRS)
timeFrame: Change from baseline to 2 hours
measure: Inverse Efficiency scores in a Modified version of the Stroop Task
timeFrame: 2 hours post intervention
measure: Flow-mediated dilatation (FMD) of the brachial artery using ultrasound (expressed as % FMD: change in brachial diameter from baseline to peak dilation following 5 minutes of arterial occlusion)..
timeFrame: Change from baseline to 2 hours
Other outcomes:
Locations:
city: Birmingham
country: United Kingdom
facility: School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham
Study officials:
affiliation: University of Birmingham
name: Catarina Rendeiro, PhD
role: PRINCIPAL_INVESTIGATOR
References: