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Characterization of the Metabolic Fate of an Oral Arginine Form

Not Applicable
Completed
Conditions
Overweight
Hypertriglyceridemic Waist
Interventions
Dietary Supplement: A form Arginine
Dietary Supplement: B form Arginine
Registration Number
NCT02352740
Lead Sponsor
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
Brief Summary

The purpose of this study is to compare the metabolic fate of two oral forms of L-Arginine in healthy subjects featuring metabolic syndrome related risk factors

Detailed Description

The study is a randomized crossover study including 16 healthy subjects with risk factors for metabolic syndrome and 16 healthy control subjects. According a double crossover design, each subject received two oral forms of L-arginine (A and B) in random order, and participated in a exploration day on the first day of arginine administration and after one week of supplementation with this arginine form. The two weeks of arginine supplementation were separated by a washout period of 2 weeks at least.

Each exploration extended over 24 hours after administration of the first arginine dose. Blood tests were performed at 0, 0.5, 1, 2, 4, 6, 8, 12, 16, 24 h after administration of the first dose. During explorations after the supplementation period, we also collected urine (0, 2, 4, 8, 12, 24 h after the first dose).

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
32
Inclusion Criteria
  • Age between 18 to 60 years old
  • Overweight (BMI between 25 and 30 kg/m²)
  • 'Hypertriglyceridemic waist' (waist circumference > 94cm for men or > 88cm for women and fasting triglyceride levels > 150 mg/dL)
Exclusion Criteria
  • Obesity (BMI> 30 kg / m²)
  • Cardiac or vascular diseases
  • Diabetes
  • Thyroid disease
  • Systolic blood pressure > 150 mmHg or diastolic blood pressure > 90 mmHg
  • Tobacco consumption > 6 cigarettes per week
  • Alcohol consumption> 3 drinks per day
  • Any medication (except contraceptive treatment) or dietary supplement intake that could not be arrested more than a week before the first visit for the duration of the study.
  • Persons under guardianship
  • Pregnancy (positive beta-hCG blood test)
  • Positive serology HBsAg AcHbc, HCV and HIV
  • Hemoglobin < 14 g/dl (for men) or <12 g / dl (for women)
  • Participation in a clinical trial within 6 months preceding the study

Healthy control subjects :

Inclusion Criteria:

  • Age between 18 to 60 years old
  • Normal weight (BMI between 18.5 and 25 kg/m²)
  • Waist circumference < 94cm for men or < 88cm for women and fasting triglyceride levels < 150 mg/dL

Exclusion Criteria :

  • Cardiac or vascular diseases
  • Diabetes
  • Thyroid disease
  • Systolic blood pressure > 150 mmHg or diastolic blood pressure > 90 mmHg
  • Tobacco consumption > 6 cigarettes per week
  • Alcohol consumption> 3 drinks per day
  • Any medication (except contraceptive treatment) or dietary supplement intake that could not be arrested more than a week before the first visit for the duration of the study.
  • Persons under guardianship
  • Pregnancy (positive beta-hCG blood test)
  • Positive serology HBsAg AcHbc, HCV and HIV
  • Hemoglobin < 14 g/dl (for men) or <12 g / dl (for women)
  • Participation in a clinical trial within 6 months preceding the study

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Healthy subjectsA form ArginineControl subjects, i.e. without overweight, elevated waist circumference and elevated fasting triglyceridemia. Intervention : A form arginine and B form arginine
Healthy subjectsB form ArginineControl subjects, i.e. without overweight, elevated waist circumference and elevated fasting triglyceridemia. Intervention : A form arginine and B form arginine
Healthy subjects with 'hypertriglyceridemic waist'A form ArginineSubjects with overweight, elevated waist circumference and elevated fasting triglyceridemia. Intervention : A form arginine and B form arginine
Healthy subjects with 'hypertriglyceridemic waist'B form ArginineSubjects with overweight, elevated waist circumference and elevated fasting triglyceridemia. Intervention : A form arginine and B form arginine
Primary Outcome Measures
NameTimeMethod
Estimate of total conversion of a dose of oral arginine into NORepeated measurement for 24h before (day 0) and after supplementation (day 8) for each treatment

This assessment uses labelled arginine (\[15N2-(guanido)\]-arginine) for the first dose of arginine taken in the morning, and measurements of 15NO3 in urine for 24h.

After administration of 15N-arginine, for each urine collection, we determined the nitrate excretion (from measurement of diuresis and nitrate concentration, by reactive chemiluminescence) and isotope 15N enrichment of nitrate ion (by microdiffusion technique and elementary analyzer connected to an isotope mass spectrometerEA-IRMS), to establish, by the principle of isotopic dilution, the total quantities of nitrate specifically from the ingested arginine. The sum of this excretion relative to the ingested dose determined the relative conversion of ingested arginine into NO.

Estimate of kinetic profiles of plasma arginine concentrations over 24 hoursRepeated measurement for 24h before (day 0) and after supplementation (day 8) for each treatment

Plasma AA concentrations were determined using an ultra-performance liquid chromatography-mass spectrometry system as previously described (Haque and al., 2012).

Secondary Outcome Measures
NameTimeMethod
Other quantitative analysisBefore supplementation (day 0) and after supplementation (day 8) for each treatment

* Fasting Asymmetric Dimethyl-L-Arginine (ADMA) concentrations were measured by an enzyme-linked immunosorbent assay.

* The fasting lipid profile (triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol) was measured and were assayed using "classical clinical biochemical analyzers".

* The fasting insulin and glucose were assayed using "classical clinical biochemical analyzers".

* Fasting metabolomic analysis

Quantitative analysis of plasma markers of endothelial functionBefore supplementation (day 0) and after supplementation (day 8) for each treatment

Fasting plasma concentrations of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule (ICAM-1), E-Selectin, P-Selectin, Plasminogen activator inhibitor-1 (PAI-1), will be determined using two custom mixed assay kits with antibody-coated beads using the Luminex xMAP technology platform for multiplexing of immunochemical bioassays.

In addition, we also have plasma concentrations of nitrite, a marker of of NO production (by reactive chemiluminescence) and other associated markers (3-nitrotyrosine, nitrosothiols, cGMP, in particular ANP, by immunochemistry).

Estimate of kinetics use of arginine for NO and urea synthesisRepeated measurement for 24h after supplementation (day 8) for each treament

After administration of 15N-arginine, we measured 15N isotopic enrichment of arginine and citrulline (by mass spectrometry coupled with gas chromatography), of plasma and urinary urea (by separation, by ion exchange, and EA-IRMS) as well as the plasma and urine concentrations in urea. These data and those of arginine and citrulline concentrations provided, by the principle of isotopic dilution, the plasma appearance of ingested arginine and the plasma appearance and urinary excretion of products of its metabolism in NO synthase and arginase ways.

These data were then subjected to a compartmental modeling work to establish the metabolic flow in these ways.

Trial Locations

Locations (1)

Centre de Recherche sur Volontaires (CRV), Hospital Avicenne

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Bobigny, Ile-de-France, France

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