Effect of Grape Seed Extract Plus Ascorbic Acid on Endothelial Function

Chronic Study of the Effect of Grape Seed Extract Plus Ascorbic Acid on Endothelial Function in Patients With Coronary Artery Disease

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00554242

Enrollment

Registered

2007-11-06

Start date

2007-07-31

Completion date

2008-12-31

Last updated

2009-06-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Coronary Artery Disease

Keywords

endothelium, antioxidants, flavonoids

Brief summary

A pilot study of 15 subjects will be conducted to confirm an acute effect of grape seed extract on endothelial function. We then will perform a a randomized, double blind, placebo controlled crossover study designed to investigate the benefit of grape seed extract/vitamin C treatment on endothelial function. Participants (n=40) will take a food supplement containing 450 mg of grape seed extract and 1500 mg of vitamin C or matching placebo for four weeks and then cross over to the alternative treatment (active supplement or placebo) for four weeks. We will examine endothelial function before and after each of the two treatment periods. The study will provide information about the vascular effects of these compounds.

Interventions

DIETARY_SUPPLEMENTGrape seed extract and ascorbic acid

Grape seed extract 450 mg and ascorbic acid 1500 mg daily

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

21 Years to 80 Years

Healthy volunteers

Inclusion criteria

* Coronary artery disease

Exclusion criteria

* Pregnancy * Clinical history of other major illness including end-stage cancer, renal failure, hepatic failure, gastrointestinal disorders that may impair absorption, or other conditions that in the opinion of the principal investigator make a clinical study inappropriate. * Treatment with an investigational new drug within the last 30 days. * History of a psychological illness or condition such as to interfere with the subject's ability to understand the requirements of the study. * Vitamin E, Vitamin C, and beta carotene, lipoic acid, and other food or herbal supplements within 1 month of enrollment.

Design outcomes

Primary

Measure	Time frame
Brachial artery flow-mediated dilation	1 month

Secondary

Measure	Time frame
Fingertip Pulse Amplitude Tonometry	1 month
Carotid-femoral pulse wave velocity	1 month
Serum markers of inflammation	1 month

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026