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Effect of a Grape Seed Extract (GSE) on Insulin Resistance

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT01889368
Recruitment Status : Completed
First Posted : June 28, 2013
Last Update Posted : June 27, 2017
Sponsor:
Collaborator:
Illinois Institute of Technology
Information provided by (Responsible Party):
University of California, Davis

Tracking Information
First Submitted Date  ICMJE October 10, 2012
First Posted Date  ICMJE June 28, 2013
Last Update Posted Date June 27, 2017
Actual Study Start Date  ICMJE November 2012
Actual Primary Completion Date March 2015   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: June 25, 2013)		 Changes in insulin resistance [ Time Frame: Baseline and 30 days ]
Insulin resistance will be assessed by comparing the baseline fasting insulin concentration to the fasting insulin concentration after intervention period of 30 days; the Homeostatic Model Assessment (HOMA) value will be utilized for comparisons.
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: June 25, 2013)
  • Changes in oxidized LDL (oxLDL) concentrations [ Time Frame: Baseline and 24 hour post-prandial response ]
    Changes in oxLDL concentrations will be assessed by ELISA methodology. Changes in the 24 hour post-prandial response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals.
  • Changes in oxidative stress [ Time Frame: Baseline and 24 hour post-prandial response ]
    Changes in the 24 hour post-prandial oxidative stress response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals. Changes in oxidative stress will be assessed by measuring cytokine production using ELISA methodology.
  • Changes in vascular stress [ Time Frame: Baseline and 1 hour post-prandial ]
    Changes in oxidative stress will be assessed by flow mediated dialysis (FMD). Changes will be assessed at baseline and one hour after capsule consumption and eating a high fat breakfast meal.
  • Changes in insulin response [ Time Frame: Baseline and 24 hour post-prandial response ]
    Changes in the 24 hour post-prandial insulin response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals.
  • Changes in oxidized LDL (oxLDL) concentrations [ Time Frame: Baseline and 30 days ]
    Changes in oxLDL concentrations will be assessed by ELISA methodology. Changes in the 24 hour post-prandial response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals. The response from the baseline visit will be compared to the response obtained during the day 30 visit.
  • Changes in insulin response [ Time Frame: Baseline and 30 days ]
    Changes in the 24 hour post-prandial insulin response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals. The response from the baseline visit will be compared to the response obtained during the day 30 visit.
  • Changes in oxidative stress [ Time Frame: Baseline and 30 days ]
    Changes in the 24 hour post-prandial oxidative stress response will be assessed at one hour intervals during the post-prandial study days, after capsule consumption and eating 3 high fat meals. Changes in oxidative stress will be assessed by measuring cytokine production using ELISA methodology. The response from the baseline visit will be compared to the response obtained during the 30 day visit.
  • Changes in vascular stress [ Time Frame: Baseline and 30 days ]
    Changes in oxidative stress will be assessed by flow mediated dialysis (FMD). Changes will be assessed at baseline and one hour after capsule consumption and eating a high fat breakfast meal. Results obtained during the first post-prandial study visit will be compared to those obtained 30 days later.
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title  ICMJE Effect of a Grape Seed Extract (GSE) on Insulin Resistance
Official Title  ICMJE Effect of a Grape Seed Extract (GSE) on Insulin Resistance
Brief Summary In people with the metabolic syndrome, the investigators hypothesize that administration of a single 300 mg dose of a grape seed extract (GSE) will reduce insulin resistance (how well cells in the body can take up and use glucose), oxidative stress, and the amount of oxidized LDL in the blood during a 24 hour period. These measurements will be assessed at hourly intervals during the 24 hour study day protocol. Additionally, the investigators hypothesize that daily administration of 300 mg of GSE for 30 days will decrease baseline insulin resistance, oxidative stress, and the level of oxidized LDL in the blood.
Detailed Description

In people with the metabolic syndrome, the investigators hypothesize that administration of a single 300 mg dose of a grape seed extract (GSE) will reduce insulin resistance (how well cells in the body can take up and use glucose), oxidative stress, and the amount of oxidized LDL in the blood during a 24 hour period. Each of these can be elevated after eating high fat meals, which are commonly found in the average Western diet. To better assess the impact of these high fat eating patterns, three standardized high fat meals will be served during the study day: breakfast, lunch, and dinner. Measurements in the blood will be assessed at hourly intervals during the 24 hour study day protocol. Additionally, the investigators hypothesize that daily administration of 300 mg of GSE for 30 days will decrease baseline insulin resistance, oxidative stress, and the level of oxidized LDL in the blood when this 24 hour study day protocol is repeated and breakfast, lunch, and dinner are again served.

Insulin resistance will be measured using a comparison of insulin and glucose levels in the blood. Oxidative stress, a measure of inflammation, will be measured by cytokines levels in the blood. The level of oxidized LDL will be measured in the blood. The investigators also plan to undertake a subsidiary pharmacokinetic study on the various polymers which are known to be present in grape seed extracts to determine their bio-availability and their relationship to the biological effects observed.
Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Condition  ICMJE Metabolic Syndrome
Intervention  ICMJE
  • Dietary Supplement: Grape Seed Extract
    300 mg capsule of Grape Seed Extract; 1 capsule will be consumed for an acute post-prandial study day and 1 capsule will be consumed daily for 30 days.
    Other Name: MegaNatural Gold
  • Dietary Supplement: Placebo
    300 mg capsule of maltodextrin; 1 capsule will be consumed for an acute post-prandial study day and 1 capsule will be consumed daily for 30 days.
    Other Name: Maltodextrin
Study Arms  ICMJE
  • Active Comparator: Grape Seed Extract
    This is a 30 day arm. At the baseline study visit, subjects will consume one 300 mg capsule of MegaNatural Gold followed by 3 high fat meals: breakfast, lunch, and dinner. Blood will be drawn at specified intervals throughout the day. Flow mediated dialysis will be performed before breakfast and again 1.5 hours later, after capsule consumption and breakfast. A minimum 14 day washout period will be between arms if this is the first arm in the randomized cross-over.
    Intervention: Dietary Supplement: Grape Seed Extract
  • Placebo Comparator: Placebo
    This is a 30 day arm. At the baseline study visit, subjects will consume one placebo (maltodextrin) capsule followed by 3 high fat meals: breakfast, lunch, and dinner. Blood will be drawn at specified intervals throughout the day. Flow mediated dialysis will be performed before breakfast and again 1.5 hours later, after capsule consumption and breakfast. A minimum 14 day washout period will be between arms if this is the first arm in the randomized cross-over.
    Intervention: Dietary Supplement: Placebo
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: June 26, 2017)		 19
Original Estimated Enrollment  ICMJE
 (submitted: June 25, 2013)		 12
Actual Study Completion Date  ICMJE March 2015
Actual Primary Completion Date March 2015   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria

  • Metabolic Syndrome, based on subject meeting at least 3 of the following criteria:
  • Abdominal obesity with waist circumference > 40 inches in men or > 35 inches in women,
  • Pre-hypertension with blood pressure > 135/85,
  • Fasting blood glucose levels above 110 mg/dl,
  • Plasma triglyceride levels in excess of 150 mg/dl,
  • HDL levels below 40 mg/dl in men or 50 mg/dl in women.

Exclusion Criteria:

  • Any known systemic disease,
  • Diabetes,
  • Alcohol consumption > 1-2 drinks/week,
  • Taking any medications or supplements that will affect metabolism, their ability to exercise or oxidative status,
  • Smokers,
  • Female subjects having abnormal menstrual cycles, taking oral contraceptives, pregnant or lactating.
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 20 Years to 70 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
 
Administrative Information
NCT Number  ICMJE NCT01889368
Other Study ID Numbers  ICMJE 329493
329493-4 ( Other Identifier: UC Davis )
Has Data Monitoring Committee No
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Current Responsible Party University of California, Davis
Original Responsible Party Chulani T. Kappagoda, M.D., University of California, Davis, Emeritus Professor of Medicine
Current Study Sponsor  ICMJE University of California, Davis
Original Study Sponsor  ICMJE Same as current
Collaborators  ICMJE Illinois Institute of Technology
Investigators  ICMJE
Principal Investigator: Chulani T Kappagoda, MD, PhD University of California, Davis
PRS Account University of California, Davis
Verification Date June 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP