VITADOSE: Vitamin D and Its Metabolites Quantification in Adipose Tissues of Obese and Non-obese Patients.
Study Details
Study Description
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: obese patients (group OB) patients with body mass index ≥ 35 kg/m² |
Biological: subcutaneous and visceral adipose tissue biopsies
Biological: blood samples analysis
|
| Active Comparator: non-obese patients (group NO) patients with body mass index < 30 kg/m² |
Biological: subcutaneous and visceral adipose tissue biopsies
Biological: blood samples analysis
|
Outcome Measures
Primary Outcome Measures
- quantification of VD and its metabolites on subcutaneous and visceral adipose tissue biopsies [12 months]
Eligibility Criteria
Criteria
Inclusion Criteria:
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Subject with a BMI greater than 35 kg / m2 (group OB) or less than 30 kg / m² (group NO)
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Subject undergoing bariatric surgery (OB group) or abdominal surgery (group NO)
Exclusion Criteria:
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Regular intake of dietary supplements or vitamin supplements in the last three months
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For the subjects of the group NO:
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Malnourished patient (BMI <18.5 kg / m2, weight loss greater than 5% in 1 month or 10% in 6 months)
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Subject with an infection or inflammatory syndrome (CRP> 10 mg / L and / or white blood cells> 12000 / mm3)
-
Non-cancerous subject
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Assistance Publique Hôpitaux de Marseille | Marseille | France | 13005 |
Sponsors and Collaborators
- Assistance Publique Hopitaux De Marseille
Investigators
- Study Director: Urielle Desalbres, Assistance Publique Hôpitaux de Marseille
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 2016-23