Brown Adipose Tissue Activation: Effect of Exercise Training and Irisin (EXEBAT)

This study investigates the brown adipose tissue (BAT) activation and metabolism using positron emission tomography (PET) imaging before and after exercise training intervention at fasting state under normal room temperature and during cold stimulation.The investigators hypothesize that BAT glucose uptake is increased after exercise and BAT becomes metabolically more active.

Understanding the mechanisms of BAT activation and the role of exercise in humans is crucial to combat epidemic of obesity and diabetes.

Study Overview

• Status: Completed
• Conditions: Physical Activity
• Intervention / Treatment: Other: Exercise

Detailed Description

Exercise training has been suggested to activate and recruit human BAT through the activation of sympathetic nervous system and contracting skeletal muscles by the release of myokines such as lactate and irisin that signal WAT to induce expression of beige adipocytes. It has been also suggested that exercise training could enhance the metabolism of already existed functional BAT by increasing uncoupling protein-1 (UCP-1) gene transcription, mitochondrial biogenesis and hyperplasia. This is of clinical relevance because brown fat activation has been found to improve metabolic factors linked to obesity and diabetes.

In this study the investigators use a PET radiotracer 2-[18F] flouro-2-deoxy-D-glucose (FDG) to quantify the glucose uptake in BAT, whie adipose tissue and the muscle.The participants are scanned thrice at fast in this study once at room temperature, second at cold exposure and third after six weeks of exercise at cold exposure. This study will provide an insight about the role of exercise in activation of BAT metabolism.

• Study Type: Interventional
• Enrollment (Actual): 11
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Healthy sedentary volunteer

  1. BMI 20-25 kg/m2
  2. Age: 18-45 years
  3. No chronic diseases

Exclusion Criteria:

1. BMI < 20 kg/m2 or BMI > 25 kg/m2
2. Mental disorder or poor compliance
3. Eating disorder or excessive use of alcohol or tobacco smoking
4. Any chronic disease
5. Past dose of radiation
6. Presence of any ferromagnetic objects that would make MR imaging contraindicated
7. Physically disability which rule out the physical fitness tests or participation in the exercise training intervention
8. Any other condition that in the opinion of the investigator could create a hazard to the subject safety, endanger the study procedures or interfere with the interpretation of study results

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: Exercise; Arm: Exercise: Combination of moderate intensity continuous training, high intensity interval training and endurance training 5 times per week for a total of 6 weeks. Out of 5 sessions three were supervised by trainer and two sessions were performed by subjects on their own.The duration of the exercise was increased progressively. The first two weeks was 30 minutes that increased to 45 minutes in the third and fourth week. It was 60 minutes for the last two weeks.

Other: Exercise

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cold-induced glucose uptake in BAT after exercise	Glucose uptake of brown adipose tissue acquired with PET under cold exposure after exercise intervention. PET imaging is used to quantify glucose uptake in tissues	Within one study day

Collaborators and Investigators

• Sponsor: Turku University Hospital
• Investigators: Principal Investigator: Pirjo Nuutila, MD, PhD, Turku UH

Study record dates

Study Major Dates

• Study Start (Actual): September 17, 2013
• Primary Completion (Actual): May 27, 2015
• Study Completion (Actual): May 27, 2015

Study Registration Dates

• First Submitted: November 27, 2017
• First Submitted That Met QC Criteria: November 30, 2017
• First Posted (Actual): December 2, 2017

Study Record Updates

• Last Update Posted (Actual): January 22, 2019
• Last Update Submitted That Met QC Criteria: January 18, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Keywords: exercise, brown adipose tissue
• Other Study ID Numbers: EXEBAT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No