Study on the Effects of Epicatechin and Quercetin Supplementation on Vascular Function and Blood Pressure (FLAVO)

Study on the Effects of Epicatechin and Quercetin Supplementation on Vascular Function and Blood Pressure in Untreated (Pre)Hypertensive Subjects

Sponsors

Lead Sponsor: Wageningen University

Collaborator: Top Institute Food and Nutrition

Source Wageningen University
Brief Summary

Flavonoid-rich foods such as tea and cocoa have been identified as having a blood pressure-lowering effect. Part of this effect is thought to be due to the flavonoid content of these foods although it is currently unknown which flavonoids play a role. Epicatechin is one the major flavonoids in cocoa while quercetin is largely found in tea. During this study the investigators plan to investigate the effects of pure epicatechin and quercetin supplementation on vascular function and blood pressure in untreated (prehypertensive) subjects by way of a three-armed double-blind crossover intervention. Participants will sequentially consume supplements containing quercetin, epicatechin or placebo for a period of 4 weeks. Before and after this 4 week period, measurements of vascular function and blood pressure will be taken. The investigators hypothesize that the supplementation of epicatechin and quercetin will improve vascular function and blood pressure.

Detailed Description

By means of a three-armed double-blind crossover intervention, the effects of pure flavonoid supplementation will be investigated. The products under investigation will be epicatechin and quercetin-3-glucoside. Subjects will be asked to consume either 160mg of quercetin-3-glucoside, 100mg of epicatechin or a placebo capsule for a period of 4 weeks. Measurements of vascular function and blood pressure will be taken before and after each 4-week intervention period. A 4-week washout period will be planned between each intervention. Measurements of vascular function will include flow-mediated dilation, pulse wave analysis, pulse wave velocity and vasomotion as well as biomarkers of inflammation and vascular function.

Overall Status Completed
Start Date 2012-09-01
Completion Date 2013-03-01
Primary Completion Date 2013-03-01
Phase N/A
Study Type Interventional
Primary Outcome
Measure Time Frame
Change in Endothelium-dependent flow-mediated dilation as a result of epicatechin and quercetin-3-glucoside supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Secondary Outcome
Measure Time Frame
Change in blood pressure as a result of epicatechin and quercetin-3-glucoside supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Change in pulse wave velocity as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Change in vasomotion as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Changes in biomarkers of endothelial function as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Changes in peripheral blood mononuclear cell gene expression of markers of inflammation as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Change in cardiovascular parameters in plasma as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Changes in pulse wave analysis as a result of epicatechin and quercetin supplementation Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20)
Adverse events Baseline and every 2 weeks thereafter (weeks 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20)
Enrollment 38
Condition
Intervention

Intervention Type: Dietary Supplement

Intervention Name: Epicatechin

Description: Subjects will be asked to consume supplements containing 100mg of epicatechin daily

Arm Group Label: Epicatechin

Intervention Type: Dietary Supplement

Intervention Name: Quercetin

Description: Subjects will be asked to consume 160mg of quercetin-3-glucoside daily

Arm Group Label: Quercetin

Intervention Type: Dietary Supplement

Intervention Name: Placebo

Description: Subjects will be asked to consume capsules containing placebo (cellulose) daily

Arm Group Label: Placebo

Eligibility

Criteria:

Inclusion Criteria: - Systolic Blood Pressure between 125 and 160 mmHg - Age between 30 and 80 years - BMI > 20 and ≤ 40 - No reported current or previous metabolic diseases - No history of cardiovascular diseases - No history of renal, liver or thyroid diseases - No history of gastrointestinal diseases - No diabetes mellitus - Fasting laboratory parameters within normal range: complete blood count (RBC, WBC, PLT, HB, HT), renal function (serum creatinine, urea), liver function (ALAT, ASAT, ɣ-GT), and serum glucose. Exclusion Criteria: - Body mass index > 40 and ≤20 - Secondary hypertension - Weight loss or weight gain of 5 kg or more during the last 2 months - Usage of non-steroidal anti-inflammatory drugs (acetylsalicylic acid, ibuprofen, naproxen) and not able or willing to stop taking them from at least 4 weeks prior to the study - Usage of cholesterol-lowering medication - Daily usage of corticosteroids - Medical treatment that may affect blood pressure and not able (or willing) to stop - Taking nutritional supplements and unwilling to discontinue - Lactating, pregnant or intention to become pregnant during study - Reported dietary habits, medically prescribed diet, slimming diet - Reported average alcohol consumption > 2 glasses/d (men) or >1 glass/d (women) - Problems with consuming the supplements or following the study guidelines - Unwilling to undergo home or office blood pressure measurements - Recent blood donation i.e. 1 month (male subjects) or 2 months (female subjects) prior to the study and planned donation during the study period - Reported intense sporting activities > 10 h/w - Not agreeing to be informed about unexpected and medically relevant personal test-results, or not agreeing that their general practitioner will be informed about these results - Participation in another biomedical trial less than 2 months before the start of the study or at the same time - No signed informed consent form - Clinical disorders that could interfere with the intervention - Unable to comply with the study procedure (e.g. holidays, urine collection, blood sampling) - Smokers - Difficulty imaging brachial artery by ultrasonography

Gender:

All

Minimum Age:

30 Years

Maximum Age:

80 Years

Healthy Volunteers:

Accepts Healthy Volunteers

Overall Official
Last Name Role Affiliation
Peter Hollman, PhD Principal Investigator Wageningen University
Location
Facility: Wageningen University
Location Countries

Netherlands

Verification Date

2012-11-01

Responsible Party

Type: Sponsor

Keywords
Has Expanded Access No
Condition Browse
Number Of Arms 3
Arm Group

Label: Epicatechin

Type: Active Comparator

Description: Subjects will be asked to consume supplements containing 100mg of epicatechin daily

Label: Quercetin

Type: Active Comparator

Description: Subjects will be asked to consume supplements containing 160mg of quercetin-3-glucoside daily

Label: Placebo

Type: Placebo Comparator

Description: Subjects will be asked to consume capsules containing a placebo (cellulose) daily

Study Design Info

Allocation: Randomized

Intervention Model: Crossover Assignment

Primary Purpose: Basic Science

Masking: Triple (Participant, Investigator, Outcomes Assessor)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact [email protected]. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Research News