Grape Pomace Polyphenols and Cardiometabolic Risk (GRAPOM)

Long-term Effects of Grape Polyphenols as Modulators of Metabolic Syndrome in Humans

The aim of this is study is to evaluate the long-term effects of grape polyphenols in the modulation of markers of metabolic syndrome. Most of the previous works about polyphenols have only considered a fraction of polyphenols, i.e., extractable polyphenols. As a consequence, an important amount of dietary polyphenols, the so-called non-extractable polyphenols are ignored. In contrast, the effect of both extractable and non-extractable polyphenols will be considered in this study. Also, studies on the long-term effect of grape polyphenol on markers of metabolic syndrome have been mostly conducted in animals, so clinical trials on this topic are needed.

Study Overview

• Status: Completed
• Conditions: Subjects at Cardiometabolic Risk
• Intervention / Treatment: Dietary supplement: GRAPOM

Detailed Description

Fifty supposedly healthy volunteers with at least two cardiometabolic risk factors were recruited. The cardiometabolic risk factors used to select the subjects are described below.

The whole intervention will be divided in 2 periods, control (CTR) and dried and milled grape pomace (GRAPOM). The two periods will have a duration of 6 weeks. During the CTR period, subjects will follow their normal dietary habits and samples will be collected at the beginning and at the end. No proper placebo could be found for the product, so this CTR period was chosen. During the GRAPOM period, the subjects will daily consume 8 g of the product solved in water and samples will be collected at the beginning and at the end.

• Study Type: Interventional
• Enrollment (Actual): 49
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Madrid, Spain, 28040
    • Institute of Food Science, Technology and Nutrition (ICTAN-CSIC)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

At least two of the following requirements:

• BMI ≥ 25 kg/m2.
• Fasting glucose values ≥ 100 mg/dL.
• Triglycerides ≥ 150 mg/dL.
• HDL-cholesterol: ≤ 50 mg/dL women, ≤ 40 mg/dL men.
• Blood pressure: systolic ≥ 130 mm Hg or diastolic ≥ 85 mm Hg.

Exclusion Criteria:

• Subjects with a pharmaceutical treatment set to modify blood pressure, lipid profile or glucose.
• Volunteers participating in other studies or weight loss plans.
• Pregnant or breastfeeding women.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: GRAPOM; Daily consumption for 6 weeks of 10 g of dried and milled grape pomaces solved in water. Samples will be collected at the beginning and the end of this period	Dietary supplement: GRAPOM; The whole intervention will be divided in 2 periods, control (CTR) and dried and milled grape pomace (GRAPOM). The two periods will have a duration of 6 weeks. During the CTR period, subjects will follow their normal dietary habits and samples will be collected at the beginning and at the end. No proper placebo could be found for the product, so this CTR period was chosen. During the GRAPOM period, the subjects will daily consume 8 g of the product solved in water and samples will be collected at the beginning and at the end.
No Intervention: CTR; Follow-up for 6 weeks without intervention. Samples will be collected at the beginning and the end of this period

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fasting insulin	Changes of blood insulin fasting levels as result of long-term supplementation with grape pomace (GRAPOM).	Up to three months
Fasting glucose	Changes of blood glucose fasting levels as result of long-term supplementation with grape pomace (GRAPOM).	Up to three months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postprandial glucose	Changes of blood glucose response after an oral glucose load as result of long-term supplementation with grape pomace (GRAPOM).	Up to four months
Postprandial insulin	Changes of blood insulin response after an oral glucose load as result of long-term supplementation with grape pomace (GRAPOM).	Up to four months
Blood pressure	Changes of blood pressure as result of long-term supplementation with grape pomace (GRAPOM).	Up to four months
Blood cholesterol (total, HDL, LDL)	Changes of blood cholesterol (total, HDL, LDL) as result of long-term supplementation with grape pomace (GRAPOM).	Up to four months
Blood triglycerides	Changes of blood triglycerides as result of long-term supplementation with grape pomace (GRAPOM).	Up to four months
Blood C reactive protein	Changes of blood C reactive protein as result of long-term supplementation with grape pomace (GRAPOM).	Up to five months
Blood fibrinogen	Changes of blood fibrinogen as result of long-term supplementation with grape pomace (GRAPOM).	Up to five months
Blood uric acid	Changes of blood uric acid as result of long-term supplementation with grape pomace (GRAPOM).	Up to five months
Iron metabolism	Changes of blood markers of iron metabolism as result of long-term supplementation with grape pomace (GRAPOM).	Up to six months
Blood polyphenols	Changes of blood polyphenols as result of long-term supplementation with grape pomace (GRAPOM).	Up to six months
Urine uric acid	Changes of urine uric acid as result of long-term supplementation with grape pomace (GRAPOM).	Up to six months
Urine polyphenols	Changes of urine polyphenols as result of long-term supplementation with grape pomace (GRAPOM).	Up to seen months
Body weight	Changes of body weight (measured at a body-impedance equipment) as result of long-term supplementation with grape pomace (GRAPOM).	Up to three months
Body fat	Changes of body fat as result of long-term supplementation with grape pomace (GRAPOM).	Up to seven months
miRNA expression	Changes of blood expression of selected miRNA as result of long-term supplementation with grape pomace (GRAPOM).	Up to eight months
Profile of fecal microbiota	Changes of fecal microbiota as result of long-term supplementation with grape pomace (GRAPOM).	Up to nine months

Collaborators and Investigators

• Sponsor: National Research Council, Spain
• Collaborators: University of the Basque Country (UPV/EHU)

Study record dates

Study Major Dates

• Study Start (Actual): March 10, 2017
• Primary Completion (Actual): July 7, 2017
• Study Completion (Actual): December 20, 2017

Study Registration Dates

• First Submitted: February 26, 2017
• First Submitted That Met QC Criteria: March 6, 2017
• First Posted (Actual): March 10, 2017

Study Record Updates

• Last Update Posted (Actual): April 5, 2018
• Last Update Submitted That Met QC Criteria: April 4, 2018
• Last Verified: April 1, 2018

More Information

Terms related to this study

• Keywords: Obesity; Metabolic syndrome; Insulin resistance; Polyphenols; Cardiometabolic risk; Grape pomace; Postprandial glucose
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Insulin Resistance; Hyperinsulinism; Metabolic Syndrome
• Other Study ID Numbers: AGL2014-55102-JIN_2

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No