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Grape Polyphenols and Metabolic Syndrome (PolyGrape)

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ClinicalTrials.gov Identifier: NCT04053569
Recruitment Status : Not yet recruiting
First Posted : August 12, 2019
Last Update Posted : August 12, 2019
Sponsor:
Information provided by (Responsible Party):
Francesco Russo, Azienda Ospedaliera Specializzata in Gastroenterologia Saverio de Bellis

Brief Summary:
Fruits and vegetables are beneficial for patients with metabolic syndrome, a condition characterized by the coexistence of various risk factors (obesity, hypertension, hypercholesterolemia, insulin resistance) that predispose to cardiovascular disease and diabetes. Diets such as the Mediterranean diet, rich in flavonoids and polyphenolic compounds can exert a high anti-inflammatory, antithrombotic and antiproliferative action. Several studies have shown that grape polyphenols exert a crucial protective action against the onset of cardiovascular, neurodegenerative, and cancer diseases. On the other hand, little information is available on the health effects deriving from the consumption of table grapes on cell membranes lipidomic profile. On this basis, the aim of this study is the evaluation of possible changes in lipidomic profile and plasma antioxidant activity induced by a diet enriched with table grape polyphenols.

Condition or disease Intervention/treatment Phase
Metabolic Syndrome, Protection Against Dietary Supplement: Table Grape supplement Not Applicable

Detailed Description:

Purified polyphenols extracted by table grape can decrease cell proliferation in vitro and exert anti-atherosclerotic and antithrombotic activities, regulating endothelial function. Literature studies have already evaluated the cytostatic and apoptotic effects produced by table grape extracts from different cultivars, demonstrating a different behavior based on extract composition. The beneficial effects of polyphenols have been attributed exclusively to their direct antioxidant action; however, in recent years it has emerged that polyphenols can interact with intracellular signaling mechanisms, modulating the activity of transcription factors involved in cell lipid metabolism. Lipidomic analysis studies the lipids in a "dynamic" way, monitoring the changes in membrane phospholipids content, caused by inflammation, stress, or malnutrition. These changes can also affect the cellular and plasmatic prothrombotic potential, which results altered in metabolic diseases. Recently, alterations in erythrocytes lipidomic profile have been detected in subjects with steatosis. Moreover, in patients with colorectal cancer patients, the presence of metastases at the time of surgery was associated with an altered profile of fatty acids in the membrane of colonic tissue cells.

Moreover, data in literature show how diet and functional foods can modify serum lipid content, in particular, an important role in the onset of dysmetabolic diseases is undoubtedly played by the different fractions of Low-Density Lipoproteins (LDL). The presence of smaller LDL fractions in the serum, such as fraction 3 and fraction 4, has been associated with the onset of cardiovascular disease and myocardial infarctions. Therefore, understanding the molecular mechanisms underlying the effects of nutraceuticals is essential to develop prevention and intervention strategies on subjects at risk for metabolic syndrome.

On this basis, the aim of this study is the evaluation of possible changes happening in lipidomic profile, plasma antioxidant activity and plasma prothrombotic potential induced by a diet enriched with table grape polyphenols in subjects with metabolic syndrome.


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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Randomized, single-blind clinical trial
Masking: Single (Participant)
Masking Description: Single (participant)
Primary Purpose: Treatment
Official Title: Effects of Polyphenols From a Table Grape on the Lipidomic Profile and Serum LDL Fractions: Possible Implications in the Metabolic Syndrome
Estimated Study Start Date : October 1, 2019
Estimated Primary Completion Date : November 1, 2020
Estimated Study Completion Date : November 1, 2021

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Experimental: Diet with table grape
Table grape (5g/Kg) administered for four weeks with dietary recommendations. A strict restriction of fruits and the limitation of other foods containing polyphenols will be necessary.
Dietary Supplement: Table Grape supplement
5g/Kg of table grape for four weeks with dietary recommendations along with a strict restriction of fruits and limitation of other foods containing polyphenols.

No Intervention: Specific dietary advice
Dietary recommendations (such as limitation of alcohol, caffeine), and low consumption of fruits.



Primary Outcome Measures :
  1. Changes in serum concentrations (mg/dL) of cholesterol, triglycerides, glucose [ Time Frame: Before the start of the study (time 0), after four weeks (time 1) and after eight weeks (time 2) ]
    Blood samples will be taken after at least 12 hours of fasting and the concentrations of cholesterol. triglycerides, and glucose will be assessed according to the standard laboratory methods (commercially available kits).

  2. Changes in blood concentration of fatty acids (stearic acid, oleic acid, arachidonic acid, eicosaepentanoic acid) expressed as percentage (%) [ Time Frame: Before the start of the study (time 0) and after eight weeks (time 2) ]
    All human blood samples are treated with chloroform: methanol (2:1, v/v), and the samples are centrifuged. The lower layer, containing fatty acids, are removed with care, replaced in a new tube and dried by a centrifugal evaporator. The fatty acid methyl ester (FAME) is obtained by adding toluene and BF3. Samples are collected and transferred into a vial and analyzed by gas chromatography.

  3. Changes in serum concentration of single subfractions of LDL (expressed as mg/dL) [ Time Frame: Before the start of the study (time 0) and after eight weeks (time 2) ]
    Small dense LDL analysis: Small dense Lipoproteins (sdLDL) are assayed using Lipoprint LDL System (Quantimetrix, USA). Each serum sample is applied on high resolution polyacrylamide gel tube in order to separate LDL fractions and subfractions by electrophoresis. The resolved lipoproteins bands are scanned and analyzed.


Secondary Outcome Measures :
  1. Changes in the concentrations of radical monocation of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) expressed as µM Trolox equivalents/g of dry weight [ Time Frame: Before the start of the study (time 0), after four weeks (time 1) and after eight weeks (time 2) ]
    The ABTS assay will be performed using the commercially available ZENBIO-AOX-1 kit.

  2. Changes in plasma prothrombotic potential [ Time Frame: Before the start of the study (time 0), after four weeks (time 1) and after eight weeks (time 2) ]
    The plasma prothrombotic potential will be evaluated using a functional test able to monitor the entire kinetics of thrombin generation, including its inactivation by plasma physiological inhibitors. In these tests, the coagulation will be activated by purified tissue factor.

  3. Changes in plasma grape miRNA content [ Time Frame: Before the start of the study (time 0) (time 1) and after eight weeks (time 2) ]
    Total serum RNA, including Small RNAs, will be extracted from plasma (200µL) of the subjects involved in the study using the miRNeasy Mini Kit (QIAGEN). After checking the concentration and quality, the effective presence of miRNAs will be verified by retro-transcription with a specific miRNA kit (TaqMan miRNA Reverse Transcription kit - Life Technologies) using Real Time-polymerase chain reaction (PCR) method.



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Ages Eligible for Study:   30 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • age > 30 years and <65 years
  • overweight.

Exclusion Criteria:

  • cardiovascular disease.
  • stroke
  • treatment with insulin or oral hypoglycemic drugs
  • fasting glucose > 126 mg / dl, or casual glycemia > 200 mg / dl
  • more than 20 g/day of alcohol intake
  • serious medical conditions that may compromise participation in the trial
  • subjects following a special diet or involved in a weight-loss program or unable to follow a diet for religious or other reasons.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04053569


Contacts
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Contact: Maria G Caruso, MD 00390804994 ext 669 gabriella.caruso@irccsdebellis.it

Locations
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Italy
IRCCS Saverio de Bellis Not yet recruiting
Castellana Grotte, Bari, Italy, 70013
Contact: Maria Notarnicola, ScD    00390804994 ext 342    maria.notarnicola@irccsdebellis.it   
Sponsors and Collaborators
Azienda Ospedaliera Specializzata in Gastroenterologia Saverio de Bellis
Investigators
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Principal Investigator: Maria Notarnicola, ScD IRCCS "Saverio de Bellis" Castellana Grotte

Publications:
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Responsible Party: Francesco Russo, Director of Nutritional Pathophysiology Laboratory - IRCCS S. de Bellis, Azienda Ospedaliera Specializzata in Gastroenterologia Saverio de Bellis
ClinicalTrials.gov Identifier: NCT04053569     History of Changes
Other Study ID Numbers: RC2019019
First Posted: August 12, 2019    Key Record Dates
Last Update Posted: August 12, 2019
Last Verified: August 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Francesco Russo, Azienda Ospedaliera Specializzata in Gastroenterologia Saverio de Bellis:
polyphenols
diet
lipidomics
metabolic syndrome
Additional relevant MeSH terms:
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Metabolic Syndrome
Syndrome
Disease
Pathologic Processes
Insulin Resistance
Hyperinsulinism
Glucose Metabolism Disorders
Metabolic Diseases