Cold Acclimation As a Modulator of Brown Adipose Tissue Function in Adults with Obesity

NCT05468151 | Active Not Recruiting

• 1 other identifier: T138/2022
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

This study will investigate the effects of at least 12 weeks of weekly cold water immersions (water temperature 18ºC) on BAT perfusion in individuals with obesity. BAT oxygen uptake and tissue perfusion will be measured using 15O-O2 and 15O-H2O PET-CT, at room temperature and after cold exposure. In addition, BAT glucose uptake will be measured using 18F-FDG after 2 hours of cold exposure and BAT NEFA uptake will be analyzed using 18F-FTHA at room temperature. To understrand the metabolic effects of BAT activation in individuals with obesity and how the cold water immersions affect the BAT perfusion in humans is critical for the development of new strategies to treat obesity and its comorbidities.

Conditions

Obesity

Outcome Measures

Primary Outcomes (1)

• Brown adipose tissue perfusion

  BAT perfusion will be measured using 15O-O2 and 15O-H2O PET-CT, at room temperature and after 2 hours of cold exposure.

  After at least 12 weeks of cold acclimation

Secondary Outcomes (2)

• Brown adipose tissue glucose uptake

  After at least 12 weeks of cold acclimation

• Brown adipose tissue NEFA uptake

  After at least 12 weeks of cold acclimation

Other Outcomes (3)

• Metabolic parameters

  After at least 12 weeks of cold acclimation

• Energy expenditure

  After at least 12 weeks of cold acclimation

• BAT gene expression

  After at least 12 weeks of cold acclimation

Study Arms (3)

Cold acclimation protocol

EXPERIMENTAL

Participants with obesity (n = 20) will undergo weekly cold water immersions (water temperature 18ºC, two to three times a week, 30 minutes per day) for, at least, 12 weeks. Before and after the cold acclimation period, the participants will undergo PET/CT scans at room temperature and after controlled cold exposure to investigate BAT perfusion, BAT glucose and NEFA uptakes.

Other: Cold acclimation

Acute cold exposure - control volunteers with obesity

OTHER

PET/CT scans will be carried out after 2 hours of cold exposure The participants in this group (n = 10) will undergo PET/CT scans at baseline and 12 weeks after the first scan. The participants will undergo PET/CT scans at room temperature and after 2 hours of controlled cold exposure to investigate BAT perfusion, BAT glucose and NEFA uptakes.

Other: Intervention Control group - volunteers with obesity

Acute cold exposure - lean controls

OTHER

PET/CT scans will be carried out after 2 hours of cold exposure The participants in this group (lean, n = 15) will undergo PET/CT scans at room temperature and after 2 hours of controlled cold exposure to investigate BAT perfusion, BAT glucose and NEFA uptakes.

Other: Acute cold exposure

Interventions

Cold acclimation OTHER

The cold water immersions will last 30-60 minutes per day and the volunteers will undergo 2-3 cold immersions per week.

Also known as: Cold immersion

Cold acclimation protocol

Intervention Control group - volunteers with obesity OTHER

Participants with obesity in the control group will undergo PET/CT scans at baseline and 12 weeks after the first scan.

Acute cold exposure - control volunteers with obesity

Acute cold exposure OTHER

All participants (lean and with obesity) will undergo PET/scans after 2 hours of cold exposure to investigate BAT perfusion and BAT glucose uptake.

Acute cold exposure - lean controls

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• BMI\>30kg/m2 (for participants with obesity)
• BMI\<25kg/m2 (for lean participants)
• Waist circumference \>94 cm for men (for participants with obesity)
• Waist circumference \> 80 for women (for participants with obesity)
• Glucose ≥7.8 and \<11 mmol/L after OGTT (for participants with obesity)

You may not qualify if:

• Being regularly exposed to cold environments for the last 3 months (e.g. having a job as a ski monitor, fishmonger, woodcutter, etc.; or doing sports/leisure activities outdoors for prolonged periods of time, etc.)
• Having gone for winter/ice swimming and bathing more than once every 2 weeks during the last 3 months.
• Inability to undergo scanning (e.g., claustrophobia)
• Pregnancy
• Smoking (or use of nicotine based products)
• Hypo/hyperthyroidism
• Malignancies
• Immune disorders
• Viral or bacterial infections
• Abnormal cardiovascular status, arrhythmia and/or long QTc in ECG, abnormal cardiac murmur, previous history of cardiovascular disease
• Allergy to lidocaine or epinephrine, or other local anaesthetics
• Weight change (intentional or not) over the last 6-months \> than 5% of body weight
• Any other cardiovascular, pulmonary, orthopaedic, neurologic, psychiatric or other conditions that in the opinion of the local clinician/researcher, would preclude participation and successful completion of the protocol, or that would negatively impact or mitigate participation in and completion of the protocol.

Sponsors & Collaborators

• Turku University Hospital: lead
• University of Turku: collaborator
• University of Barcelona: collaborator
• University of Ottawa: collaborator

Study Sites (1)

Turku PET Centre

Turku, Turku, 20520, Finland

Location

MeSH Terms

Conditions

Obesity

Interventions

Adiposity

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Body Fat Distribution; Body Weights and Measures; Body Constitution; Physical Examination; Diagnostic Techniques and Procedures; Diagnosis; Body Composition; Biochemical Phenomena; Chemical Phenomena; Metabolism; Physiological Phenomena

Study Officials

• Kirsi A Virtanen

  Turku University Hospital

  PRINCIPAL INVESTIGATOR

• Francisco Acosta, PhD

  Turku PET Centre

  STUDY DIRECTOR

• Mueez U-Din, PhD

  Turku PET Centre

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor at Turku PET Centre

Study Record Dates

• First Submitted: July 19, 2022
• First Posted: July 21, 2022
• Study Start: July 25, 2022
• Primary Completion: December 20, 2024
• Study Completion (Estimated): July 1, 2026
• Last Updated: March 4, 2025

Record last verified: 2025-02

Data Sharing

• IPD Sharing: Will not share

Locations

FI (1)