Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Class |
|---|---|
| Top Institute Food and Nutrition | OTHER |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
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.
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.
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Epicatechin | Active Comparator | Subjects will be asked to consume supplements containing 100mg of epicatechin daily |
|
| Quercetin | Active Comparator | Subjects will be asked to consume supplements containing 160mg of quercetin-3-glucoside daily |
|
| Placebo | Placebo Comparator | Subjects will be asked to consume capsules containing a placebo (cellulose) daily |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Epicatechin | Dietary Supplement | Subjects will be asked to consume supplements containing 100mg of epicatechin daily |
|
| Measure | Description | Time Frame |
|---|---|---|
| Change in Endothelium-dependent flow-mediated dilation as a result of epicatechin and quercetin-3-glucoside supplementation | Change in arterial diameter as a result of 5 minute arterial occlusion (200mmHg). Arterial diameter will be measured by means of ultrasonography. | Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20) |
| Measure | Description | Time Frame |
|---|---|---|
| Change in blood pressure as a result of epicatechin and quercetin-3-glucoside supplementation | Office BP (Dinamap, 4 consecutive measurements with 2-min intervals)and 24-hour ABPM (Spacelab; 1x24h) | 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 |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Peter Hollman, PhD | Wageningen University | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| Wageningen University | Wageningen | 6703 HD | Netherlands |
| PubMed Identifier | Type | Citation | Retractions |
|---|---|---|---|
| 30398646 | Derived | Van den Eynde MDG, Geleijnse JM, Scheijen JLJM, Hanssen NMJ, Dower JI, Afman LA, Stehouwer CDA, Hollman PCH, Schalkwijk CG. Quercetin, but Not Epicatechin, Decreases Plasma Concentrations of Methylglyoxal in Adults in a Randomized, Double-Blind, Placebo-Controlled, Crossover Trial with Pure Flavonoids. J Nutr. 2018 Dec 1;148(12):1911-1916. doi: 10.1093/jn/nxy236. | |
| 25972527 |
| Label | URL |
|---|---|
| Website for the study (in dutch) | View source |
Not provided
Not provided
| ID | Term |
|---|---|
| D006973 | Hypertension |
| ID | Term |
|---|---|
| D014652 | Vascular Diseases |
| D002318 | Cardiovascular Diseases |
Not provided
Not provided
| ID | Term |
|---|---|
| D002392 | Catechin |
| D011794 | Quercetin |
| ID | Term |
|---|---|
| D002839 | Chromans |
| D001578 | Benzopyrans |
| D011714 | Pyrans |
| D006573 | Heterocyclic Compounds, 1-Ring |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Quercetin | Dietary Supplement | Subjects will be asked to consume 160mg of quercetin-3-glucoside daily |
|
| Placebo | Dietary Supplement | Subjects will be asked to consume capsules containing placebo (cellulose) daily |
|
Measured using a SphygmoCor device at baseline and the end of each intervention |
| Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20) |
| Change in vasomotion as a result of epicatechin and quercetin supplementation | Measured using a PeriFlux 5001 device at baseline and the end of each intervention. | 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 | Plasma analysis of endothelin-1, ADMA, MCP-1, sVCAM-1, sICAM-1, sE-selectin, sTM, CRP, SAA, IL-6, IL-8, TNF-α, vWF, nitric oxide | 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 | PBMC gene expression of markers of inflammation | 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 | Total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, insulin and glucose | 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 | Measured using a SphygmoCor device at baseline and the end of each intervention | Baseline and every 4 weeks thereafter (weeks 4, 8, 12, 16 and 20) |
| Adverse events | During the study subjects will be asked to maintain a diary in which they can report any adverse events they may have a result of the supplements. Diaries will be checked every 2 weeks. Study subjects will also be asked to contact the research team if they experience repeated adverse events. | Baseline and every 2 weeks thereafter (weeks 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20) |
| Dower JI, Geleijnse JM, Gijsbers L, Schalkwijk C, Kromhout D, Hollman PC. Supplementation of the Pure Flavonoids Epicatechin and Quercetin Affects Some Biomarkers of Endothelial Dysfunction and Inflammation in (Pre)Hypertensive Adults: A Randomized Double-Blind, Placebo-Controlled, Crossover Trial. J Nutr. 2015 Jul;145(7):1459-63. doi: 10.3945/jn.115.211888. Epub 2015 May 13. |
| 25934864 | Derived | Dower JI, Geleijnse JM, Gijsbers L, Zock PL, Kromhout D, Hollman PC. Effects of the pure flavonoids epicatechin and quercetin on vascular function and cardiometabolic health: a randomized, double-blind, placebo-controlled, crossover trial. Am J Clin Nutr. 2015 May;101(5):914-21. doi: 10.3945/ajcn.114.098590. Epub 2015 Feb 25. |
| D006571 |
| Heterocyclic Compounds |
| D005419 | Flavonoids |
| D002867 | Chromones |
| D006574 | Heterocyclic Compounds, 2-Ring |
| D000072471 | Heterocyclic Compounds, Fused-Ring |
| D044948 | Flavonols |