Vitamin D and Its Metabolites Quantification in Adipose Tissues of Obese and Non-obese Patients.

NCT03008525 | Recruiting

• 1 other identifier: 2016-23
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Vitamin D (VD) is a pleiotropic hormone, involved in many physiological processes including calcium and phosphorus absorption. The VD metabolism begin to be well-known and involves a hepatic hydroxylation (mediated by enzymes, which belong to the cytochrome P450 family) leading to the production of the 25(OH)D, which corresponds to the circulating form of the VD. After circulation in blood, the 25(OH)D is submitted to a second hydroxylation in the kidney resulting to the generation of 1,25(OH)2D, the active metabolite of VD. Numerous epidemiological studies reported an inverse relationship between obesity and circulation level of 25(OH)D. Several mechanisms could explain the low level of 25(OH)D observed in obese subjects, the more classical evoked being based on sequestration and/or dilution of VD in adipose tissue (AT), the main VD storage site. However, this mechanism has never been demonstrated. In order to confirm this hypothesis, the concentration of VD and its metabolites in adipose tissue need to be quantified. The objective of this study is to determine the concentration of VD and its metabolites in adipose tissue as well as adipose tissue mass quantification and distribution (visceral or subcutaneous) to highlight putative difference of VD and its metabolites quantities between obese and non-obese patients. A quantification of VD metabolism, inflammation and lipid metabolism gene expression will be realized on biopsies. Correlations between gene expression and quantity of VD in tissue will be carrying out.

Conditions

Obesity; Endocrine

Outcome Measures

Primary Outcomes (1)

• quantification of VD and its metabolites on subcutaneous and visceral adipose tissue biopsies

  12 months

Study Arms (2)

obese patients (group OB)

EXPERIMENTAL

patients with body mass index ≥ 35 kg/m²

Biological: subcutaneous and visceral adipose tissue biopsies; Biological: blood samples analysis

non-obese patients (group NO)

ACTIVE COMPARATOR

patients with body mass index \< 30 kg/m²

Biological: subcutaneous and visceral adipose tissue biopsies; Biological: blood samples analysis

Interventions

subcutaneous and visceral adipose tissue biopsies BIOLOGICAL

Subcutaneous and visceral adipose tissue biopsies during operation

non-obese patients (group NO); obese patients (group OB)

blood samples analysis BIOLOGICAL

Blood sampling is required to measure plasma cholecalciferol, calcidiol and calcitriol concentrations, as well as biological parameters of interest. Another plasma/serum tube is used to measure pro- and anti-inflammatory cytokines and adiponectin.

non-obese patients (group NO); obese patients (group OB)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Subject with a BMI greater than 35 kg / m2 (group OB) or less than 30 kg / m² (group NO)
• Subject undergoing bariatric surgery (OB group) or abdominal surgery (group NO)

You may not qualify if:

• Regular intake of dietary supplements or vitamin supplements in the last three months
• For the subjects of the group NO:
• Malnourished patient (BMI \<18.5 kg / m2, weight loss greater than 5% in 1 month or 10% in 6 months)
• Subject with an infection or inflammatory syndrome (CRP\> 10 mg / L and / or white blood cells\> 12000 / mm3)
• Non-cancerous subject

Sponsors & Collaborators

• Assistance Publique Hopitaux De Marseille: lead

Study Sites (1)

Assistance Publique Hôpitaux de Marseille

Marseille, 13005, France

RECRUITING

MeSH Terms

Conditions

Obesity

Interventions

Injections, Subcutaneous

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Injections; Drug Administration Routes; Drug Therapy; Therapeutics

Study Officials

• Urielle Desalbres

  Assistance Publique Hôpitaux de Marseille

  STUDY DIRECTOR

Central Study Contacts

Rene VALERO

CONTACT

0491383393; rene.valero@ap-hm.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 29, 2016
• First Posted: January 2, 2017
• Study Start: March 17, 2017
• Primary Completion: September 13, 2025
• Study Completion (Estimated): September 13, 2026
• Last Updated: July 27, 2023

Record last verified: 2023-05

Locations

FR (1)