Vitamin A in Brown Fat Activity

August 16, 2018 updated by: Dr. Florian Kiefer, Medical University of Vienna

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

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

66

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Austria
      • Vienna, Austria, 1090
        • Medical University of Vienna

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

20 years to 45 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Lean
Cold exposure
Other: Cold exposure
Experimental: Obese
Cold exposure
Other: Cold exposure

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Correlation between retinol/retinol-binding protein concentrations and cold-induced brown fat acitivity
Time Frame: 6 years
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 Outcome Measures

Outcome Measure
Measure Description
Time Frame
Analyses of potential BAT or browning markers in humans
Time Frame: 6 years
6 years
Association between BAT activity and energy expenditure
Time Frame: 6 years
6 years
Identification of new factors related to brown fat function
Time Frame: 6 years
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

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medical University of Vienna

Investigators

  • Principal Investigator: Florian Kiefer, MD, PhD, Medical University of Vienna

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

February 1, 2014

Primary Completion (Actual)

April 15, 2018

Study Completion (Actual)

April 15, 2018

Study Registration Dates

First Submitted

February 14, 2015

First Submitted That Met QC Criteria

March 5, 2015

First Posted (Estimate)

March 6, 2015

Study Record Updates

Last Update Posted (Actual)

August 20, 2018

Last Update Submitted That Met QC Criteria

August 16, 2018

Last Verified

August 1, 2018

More Information

Terms related to this study

Other Study ID Numbers

  • 1032/2013

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Brown Adipose Tissue

Clinical Trials on Cold exposure

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Philippines

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe