Vitamin A in Brown Fat Activity

Brown Adipose Tissue Clinical Trial

Official title:

The Role of Vitamin A in Brown Fat Activity and Energy Metabolism

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02381483
• Other study ID #: 1032/2013
• Status: Completed
• Phase: N/A
• Start date: February 2014
• Est. completion date: April 15, 2018

Study information

• Verified date: August 2018
• Source: Medical University of Vienna
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Vitamin A metabolites (retinoids) have shown to activate brown fat function in preclinical studies, however the role of retinoids in human brown fat physiology and energy metabolism remains elusive. This study aims to identify a possible association between retinoid metabolism, brown fat activity, and energy expenditure in lean and obese subjects by using FDG-PET-CT, PET-MR Scans and indirect calorimetry. Additionally we will analyze the genetic profile of white and brown neck fat biopsies at room temperature and cold conditions in a subset of the study participants. More detailed molecular studies (involving other potential browning markers) will also be performed in adipocytes derived from human SVC.

The optimal duration of cold exposure will be determined in a pilot study. Therefore subjects will be repeatedly exposed to cold and circulating retinoid levels and other plasma parameters will be measured at various time points.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 66
• Est. completion date: April 15, 2018
• Est. primary completion date: April 15, 2018
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 20 Years to 45 Years

Eligibility

Inclusion Criteria:

• Age 20 - 45 years.

• Body mass index (BMI) 18.5 - 24.9 kg/m2 (lean) or 30.0 - 38.0 kg/m2 (obese)

Exclusion Criteria:

• Endocrine (except hyperlipidemia), cardiovascular (except hypertension), liver, kidney, inflammatory bowel, rheumatic, oncologic disease or any other chronic condition.

• Medication for any of the above mentioned conditions.

• Pregnancy

• Metallic implants that are not MRI compatible

Related Conditions & MeSH terms

• Brown Adipose Tissue

Intervention

Other:
• Cold exposure

Locations

Country	Name	City	State
Austria	Medical University of Vienna	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Medical University of Vienna

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Correlation between retinol/retinol-binding protein concentrations and cold-induced brown fat acitivity	A possible association between serum retinol and retinol-binding protein concentrations and cold-induced brown fat activity in lean and obese subjects, respectively, will be analyzed.	6 years
Secondary	Analyses of potential BAT or browning markers in humans		6 years
Secondary	Association between BAT activity and energy expenditure		6 years
Secondary	Identification of new factors related to brown fat function	This is a very exploratory aim that involves a number of molecular tests. Therefore no single outcome measure can be defined here. Briefly, we will perform mRNA and miRNA analyses from BAT biopsies and plasma before and after cold exposure to identify new factors related to BAT function. Potential candidates will be tested in loss- or gain-of-function models in isolated human and/or murine adipocytes. In addition, the thermogenic effects of commercially available peptides, hormones, lipids, or steroid acids, will be tested in primary adipocytes.	6 years