Investigating the Cellular Heterogeneity of Human Brown Adipose Tissue and Its (Patho)Physiological Regulation

What this Trial Is About

Researchers are studying how repeated short-term exposure to cold affects the molecular and physiological function of brown adipose tissue (BAT), a fat tissue linked to better heart and metabolic health. This trial involves healthy adults aged 18 to 40 years and aims to understand how cold exposure changes gene expression and cell types in BAT, white adipose tissue (WAT), and skeletal muscle. The study focuses on the molecular adaptations in these tissues that occur with cold exposure, which are not well understood yet. Participants will undergo a 10-day cold acclimation process, spending 2 hours daily using water-perfused cooling blankets to expose their bodies to cold. Before and after this period, participants will have baseline and follow-up visits where various assessments are done. These include blood sampling, measurements of energy use, skin and core body temperatures, muscle activity, and advanced PET/CT scans using an injected tracer (18F-FDG) during cold exposure. Tissue biopsies from BAT, WAT, and skeletal muscle will be taken under local anesthesia before and after acclimation to study cellular changes. During the trial, participants will have continuous monitoring of core and skin temperatures with special sensors and electronic capsules. Muscle activity and shivering will be measured using skin electrodes. Energy expenditure will be assessed using indirect calorimetry. Researchers will compare all these measurements before and after the cold exposure period to evaluate changes in tissue activity, cold tolerance, immune responses, and gene expression. The study is expected to last about one year for outcome analysis after the initial interventions.

Intermittent Cold Exposure and Brown Adipose Tissue Hyperplasia