The Physiological Responses and Adaptation of Brown Adipose Tissue to Chronic Treatment With Beta3-Adrenergic Receptor Agonists
Trial Parameters
Eligibility Fast-Check
Enter your details for a quick preliminary check. This does not replace medical advice.
Brief Summary
Background: Brown adipose tissue (BAT) is a type of fat in the body. It may prevent weight gain, improve insulin sensitivity, and reduce fatty liver. Researchers want to see if BAT helps the body burn energy. Objective: To learn more about how BAT works to burn energy. Eligibility: People ages 18-40 with a body mass index between 18 and 40 Design: Participants will be screened with: Medical history Physical exam Blood, urine, and heart tests Dietitian interview Participants will have an overnight baseline visit. This includes: Repeats of screening tests Exercise test Scans. For one scan, a radioactive substance is injected into the arm. FSIVGIT: An IV is inserted into veins in the right and left arms. Glucose and insulin are injected in one arm. Blood glucose and insulin levels are measured from the other. Metabolic suite: Participants stay 18-19 hours in a room that measures their metabolic rate. Monitors on the body measure heart rate, movement, and temperature. Optional fat biopsy: A small piece of tissue is removed with a needle. Participants will take 2-4 pills daily for 4 weeks. All women will take the drug mirabegron. Men will be randomly get either the drug or a placebo. All participants will have a visit after 2 weeks of the pills. They will repeat the screening tests. Participants will have an overnight visit 2 weeks later. They will repeat the baseline tests. Participants will keep food and medication diaries. Participants will have a follow-up visit 2 weeks after stopping the pills. This includes heart tests.
Eligibility Criteria
* INCLUSION CRITERIA In order to be eligible to participate in this study, an individual must meet all of the following criteria: Cohort 1: (complete) 1. Female 2. Age 18-40 years 3. BMI 18.00-40.0 kg/m\^2 4. Able to understand the research and willing to sign a written informed consent document Cohort 2: (complete) 1. Male 2. Age 18-40 years 3. BMI 18.00-40.0 kg/m\^2 4. Able to understand the research and willing to sign a written informed consent document Cohort 3: 1. Female 2. Age 18-40 years 3. BMI 25.0-50.0 kg/m\^2 or BMI \> 18.5 kg/m\^2 with PCOS diagnosis 4. Diagnosis of PCOS based on NIH Criteria; defined by the presence of both clinical and/or biochemical signs of hyperandrogenism and oligo- or chronic anovulation. 5. Women of childbearing potential must agree to use a highly effective method of birth control, confirmed by the Investigator, for at least 3 months prior to the first study visit and continuing throughout the study duration. a. Highly effective methods of birth co