Energy Metabolism and Brown Adipose Tissue Activity in Individuals With Gilbert's Syndrome and Healthy Controls

What this Trial Is About

This research investigates the relationship between bilirubin metabolism and metabolic health by comparing individuals with Gilbert's syndrome (GS) to healthy controls. The study focuses on energy metabolism, body composition, and the activity of brown adipose tissue (BAT) in these two groups. Researchers aim to understand why people with GS show a distinct metabolic profile linked to mildly elevated bilirubin levels and its potential health effects. Participants will undergo several diagnostic procedures over three separate days. These include cold exposure to stimulate brown fat, PET-CT imaging to assess BAT, MRI scans of the liver, abdominal fat, and muscle, blood sampling, indirect calorimetry to measure energy expenditure, bioelectrical impedance analysis for body composition, and infrared thermography. The study groups consist of 40 individuals with GS and 40 matched controls based on age and gender, distinguished by their bilirubin blood levels. Each participant will attend three study days involving fasting before key measurements. On the first day, brown adipose tissue activity is measured; on the second day, fat distribution in the liver and muscle is assessed. Participants also complete dietary and physical activity questionnaires. The primary outcome is the activation of brown adipose tissue induced by cold over 12 hours across the three days. Researchers will monitor metabolic health, body composition, and BAT activity to compare GS individuals with controls. The study is conducted by the Medical University of Vienna and lasts approximately three days per participant.

Brown Adipose Tissue Activity in Gilbert's Syndrome