Racial and Aging Effects of Acute Antioxidant Supplementation (RACE)

June 12, 2015 updated by: Bo Fernhall, University of Illinois at Chicago

This research is,being done to better understand how antioxidants (vitamins C, E and Alpha Lipoic Acid) af,f,ect the heart,and arteries. For this study, we will obtain blood samples to measure oxidative stress markers (substances in the blood that are linked to oxidative stress), cholesterol, insulin and blood glucose (sugar), as well as measure how well the heart and arteries are working following supplementation with the antioxidants.

Our central hypothesis is that acute antioxidant supplementation will improve arterial function at rest and during exercise in African Americans without an impact of age, whereas aging will modify these effects in Caucasians.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The overall goal of this application is to investigate the effect of aging on how acute antioxidant supplementation affects decrements in arterial function observed in African Americans (AA). Additionally, this application will facilitate the applicant's emergence as an independent investigator in integrative clinical physiology. Oxidative stress (OS), contributes to hypertension, diabetes, heart failure, atherosclerosis, sepsis and aging. Increased OS leads to the development of endothelial dysfunction and subsequent development of cardiovascular disease through the inactivation of nitric oxide (NO) by superoxide (O2) and other free radicals. African Americans (AA) have increased OS and inflammation in vivo and in vitro, and have a lower serum concentration of most antioxidants. Endothelial cells of AAs have steady state NO/ O2/ONOO- balance that is close to redox state, which is a characteristic of endothelium impaired function disorders. Endothelium-derived NO is a vasodilator and inhibits monocyte adhesion and platelet activity and therefore is important in the maintenance of vascular homeostasis. These specific differences in OS could be a contributing mechanism to the high prevalence of cardiovascular disease, especially hypertension and heart failure, observed in AA. Aging causes increases in OS, endothelial dysfunction, and decreased arterial compliance, thus increasing the risk of cardiovascular disease. Acute supra-physiological dosages of antioxidants have been shown to transiently restore endothelial function in older adults and patients with coronary artery disease and hypertension by scavenging free radicals.However, it is unknown if acute antioxidant supplementation can diminish differences in vascular function between AA and Caucasians (CA). It is also unknown if acute antioxidant supplementation with known efficacy will differentially affect blood flow in AA vs CA during exercise.

Study Type

Interventional

Enrollment (Actual)

93

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Illinois
      • Chicago, Illinois, United States, 60612
        • University of Illinois - Chicago

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (ADULT, OLDER_ADULT)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • 18-35 or 55-75 years of age
  • General Good health
  • Without diagnosed atherosclerotic disease
  • Without metabolic or inflammatory disease
  • Do not use antioxidant vitamin supplementation
  • Do not use anti-inflammatory medication within last 2 weeks
  • Do not use steroidal substances within past 2 weeks
  • Participants on medications (not listed in the Exclusion Criteria) will take medication as normal on all days of study visits.

Exclusion Criteria:

  • Current smoker
  • Severe obesity (BMI>40 kg/m2)
  • Blood pressure greater than 140/90 mmHg
  • Diabetes (fasting glucose >110 mg/dl)
  • Hyperlipidemia (total cholesterol >240 mg/dl)
  • Inflammatory disease (rheumatoid arthritis, systemic lupus erythematosus, etc)
  • Diagnosed atherosclerotic heart disease
  • Diagnosed cardiac arrhythmia
  • Bacterial, viral or upper respiratory infection within past 1 month
  • Bleeding disorder
  • Anticoagulant medication
  • Pregnant women

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: PREVENTION
  • Allocation: RANDOMIZED
  • Interventional Model: CROSSOVER
  • Masking: DOUBLE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
PLACEBO_COMPARATOR: Placebo
Placebo will be ingested in front of laboratory personnel in two doses, separated by 30 minutes to increase absorption, consumed 90 and 60 minutes before the testing protocol. Placebo microcrystalline cellulose capsules will be of similar taste, color and appearance.
Dietary supplement: Antioxidant
Comparison of antioxidant supplementation with a placebo. Effects of race and age and race in repsonse to the supplementation will be evaluated.
Other Names:
  • Vitamin E, Vitamin C, α-lipoic acid
Other: Placebo
Comparison of antioxidant supplementation with a placebo. Effects of race and age and race in repsonse to the supplementation will be evaluated.
Other Names:
  • No other names
EXPERIMENTAL: Antioxidant

Supplementation will be ingested in front of laboratory personnel in two doses, separated by 30 minutes to increase absorption, consumed 90 and 60 minutes before the testing protocol. The first dose will consist of 300 mg of α-lipoic acid, 500 mg of vitamin C, and 200 IU of vitamin E, and the second dose will be 300 mg of α-lipoic acid, 500 mg of vitamin C, and 400 IU.

of vitamin E.
Dietary supplement: Antioxidant
Comparison of antioxidant supplementation with a placebo. Effects of race and age and race in repsonse to the supplementation will be evaluated.
Other Names:
  • Vitamin E, Vitamin C, α-lipoic acid
Other: Placebo
Comparison of antioxidant supplementation with a placebo. Effects of race and age and race in repsonse to the supplementation will be evaluated.
Other Names:
  • No other names

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Arterial stiffness
Time Frame: 2 weeks
The overall aim of this study is to examine the effects of an acute dose of an antioxidant cocktail on arterial stiffness (measured by ventral pulse wave velocity) in younger and older African Americans in comparison to younger and older Caucasians.
2 weeks
Arm blood flow
Time Frame: 2 weeks
A second primary outcome is arm blood flow at rest and during two different intensities of hand grip exercise
2 weeks
Endothelial function
Time Frame: 2 weeks
A third primary outcome is endothelial function assessed through brachial artery flow mediated dilation.
2 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Blood pressure
Time Frame: 2 weeks
Both brachial and central blood pressure will be measured as secondary outcomes.
2 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Illinois at Chicago

Investigators

  • Principal Investigator: Bo Fernhall, Ph.D., University of Illinois at Chicago

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2014

Primary Completion (ACTUAL)

September 1, 2014

Study Completion (ACTUAL)

June 1, 2015

Study Registration Dates

First Submitted

June 1, 2014

First Submitted That Met QC Criteria

June 3, 2014

First Posted (ESTIMATE)

June 5, 2014

Study Record Updates

Last Update Posted (ESTIMATE)

June 16, 2015

Last Update Submitted That Met QC Criteria

June 12, 2015

Last Verified

June 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2013-0980

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 register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Healthy

Clinical Trials on Antioxidant

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Colombia

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe