Effect of Polyphenol Extract on Cardiovascular Health Markers: a 4 Way Randomised Crossover Study

Not Applicable

• Conditions: Blood Pressure; Cardiovascular Diseases; Endothelial Dysfunction
• Interventions: Dietary Supplement: Polyphenol extract; Dietary Supplement: Placebo

• Registration Number: NCT05220059
• Lead Sponsor: University of Ulster

Brief Summary

Endothelial dysfunction is an early predictor of cardiovascular events in at-risk patients. It is characterized by impaired endothelium-dependent dilation and is primarily caused by reduced nitric oxide bioavailability secondary to oxidative stress and inflammation. Finding dietary/dietary supplement-oriented approaches to improving endothelial function is of public health interest.

A randomized double-blind placebo controlled 4-way crossover study will be conducted to determine if acute consumption of a proprietary polyphenol extract (156 mg / 222 mg / 333 mg) will have a dose dependent response on endothelium-dependent flow-mediated dilation (ED-FMD) in fasting conditions, in comparison to a placebo (maltodextrin) in male smokers (20 - 45 years; n=20).FMD and blood pressure will be assessed at 0 \& 2 hour timepoints following consumption of a single dose of polyphenol extract, accompanying blood samples will be collected to assess a range of endpoints including nitric oxide metabolites, angiotensin and polyphenols metabolites. Endothelium-independent vasodilation will also be measured 2 hours post consumption.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-11-26
• Study Start: 2021-12-01
• Primary Completion: 2021-12-01
• Study First Submitted QC: 2022-01-28
• Study First Posted: 2022-02-02
• Status Verified: 2022-03
• Last Update Submitted: 2022-03-10
• Last Update Posted: 2022-03-11
• Study Completion: 2022-06-30

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Male
• Target Recruitment: 20

Inclusion Criteria

• At least two of the following risk markers; a BMI 25-30, waist circumference >94 cm, high normal blood pressure defined as either systolic 85-89 mmHg or diastolic 130-139 mmHg and have a normal ECG.

Exclusion Criteria

• An individual who has tested positive (self reported) 2 weeks before the study period.
• A COVID-19 vaccinated individual who while receive the 1st or 2nd dose or booster 2 weeks before V0 or during the study period, due to the potential interaction of vaccine on markers assessed

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Polyphenol extract medium dose	Polyphenol extract	222mg single dose
Polyphenol extract high dose	Polyphenol extract	333mg single dose
Placebo	Placebo	Maltodextrin single dose
Polyphenol extract low dose	Polyphenol extract	156mg single dose

Primary Outcome Measures

Name	Time	Method
Flow Mediated Dilation	Change over 2 hours post dose	Acute change in endothelium-dependent flow-mediated dilation

Secondary Outcome Measures

Name	Time	Method
Systolic blood pressure	Change over 2 hours post dose	Measured by brachial cuff
Diastolic blood pressure	Change over 2 hours post dose	Measured by brachial cuff
Endothelium-independent vasodilation	Change after 2 hours post dose	Acute change in endothelium-independent vasodilation in response to Glyceryl trinitrate (GTN) drug

Trial Locations

Locations (1)

Human Intervention Studies Unit, Ulster University; 🇬🇧 Coleraine, Co.Londonderry, United Kingdom