Polyphenols and Overfeeding

Hospices Civils de Lyon42 enrolled

Overview

Obesity is a complex and multifactorial disease representing a major public health challenge. Indeed, overweight and obese people carry a major risk of developing insulin resistance and type 2 diabetes mellitus. It has been demonstrated that polyphenols could be used to counteract some of the mechanisms involved in the generation of insulin resistance. The model of overfeeding represents a very good study model of the metabolic complications of obesity, since it has been shown to induce a transient state of insulin resistance in the human. The purpose of this research is to study the effects of a overfeeding (+50% of daily caloric needs over 31 days) with or without polyphenols supplementation (2g/days over 31 days) on insulin sensitivity measured in the setting of a hyperinsulinemic euglycemic clamp and on post prandial partitioning of exogenous lipids after a test meal. During 31 days, the volunteers will consume chocolate bars, chips, chocolate breads and cola in addition to their usual diet and will be supplemented with 2g of grape polyphenols extract or with placebo.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

QUADRUPLE

Enrollment

Conditions

Overfeeding

Interventions

Eligibility

Sex: MALEMin age: 18 YearsMax age: 55 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Male * Aged from 18 to 55 years * Body Mass Index of 23 to 27 kg/m² * Normal blood pressure * Fasting glycemia \< 7 mmol/L * CRPus \< 10mg/L * Triglycerides ≤ 3mmol/L Exclusion Criteria: * Medical or surgical history which may affect the results (renal -cardiovascular - hepatic- endocrine-inflammatory diseases) * Subjects under treatment which may interfere with the measured parameters * Eating disorder * Intensive sportive activity * Dairy products allergy or intolerance

Outcomes

Primary Outcomes

Peripheral insulin sensitivity

Volunteers will have peripheral and hepatic insulin sensitivity determined by using a two-stage hyperinsulinemic euglycemic clamp with stable isotopically labeled tracer infusion.

Time frame: During 31 days

Secondary Outcomes

Hepatic insulin sensitivity

Endogenous glucose production (EGP) will be determined during the last 30 minutes of the low-dose insulin infusion.

Time frame: before and after the 31 days of overfeeding

Change in genes expression in adipose and muscle tissues

RT-PCR

Time frame: Before and after the 31 days of overfeeding

Anthropometry, Fat quantification and Abdominal fat distribution

Weight, height, waist and hip circumferences, fat mass using dual x-ray absorptiometry (DEXA) and abdominal fat distribution using resonance magnetic imaging (RMI).

Time frame: During 31 days

Fasting and Postprandial partitioning of exogenous lipid

13C enrichment will be measured in blood samples and breath test during a test meal performed before and after the 31 days of overfeeding.

Time frame: Fasting and during all the postprandial period (0-300 minutes)

Modification in intestinal microbiota

Feces analyses