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The Physiological Responses and Adaptation of Brown Adipose Tissue to Chronic Treatment With Beta3-Adrenergic Receptor Agonists

Phase 1
Recruiting
Conditions
Polycystic Ovary Syndrome
Interventions
Other: B Complex Plus Vitamin C Tablets
Registration Number
NCT03049462
Lead Sponsor
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
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.

Detailed Description

Study Description:

This study is intended to address questions about human brown adipose tissue (BAT). Specifically, we plan to visualize BAT activity with acute cold exposure during drug naive and drug experienced visits. Thus, we will be studying changes in BAT activity from a chronic dosage of mirabegron.

Objectives:

Cohort 1: To measure changes in BAT metabolic activity in women seen after four weeks of daily treatment with the beta3-AR agonist mirabegron.

Cohort 2: To measure changes in BAT metabolic activity in men seen after four weeks of daily treatment with 200 mg of the beta3-AR agonist mirabegron compared to placebo

Cohort 3: To compare the changes in insulin sensitivity in each woman after four weeks of daily treatment with 100 mg of the beta3-AR agonist mirabegron with the changes in insulin sensitivity in each woman after four weeks of daily treatment with placebo

Primary Endpoints:

Cohort 1: The change in detectable cold exposure induced BAT metabolic activity in women, as visualized by F-FDG PET/CT.

Cohort 2: The change in detectable cold exposure induced BAT metabolic activity, as visualized by 18F-FDG PET/CT

Cohort 3: The change in glucose infusion rate, as measured by the hyperinsulinemic euglycemic clamp, in women after four weeks of daily treatment with 100 mg of the beta3-AR agonist mirabegron with the change in glucose infusion rate after four weeks of daily treatment with placebo

Secondary Endpoints:

1. To identify changes in metabolic health arising from BAT activation and/or prolonged treatment with regular 100 mg (females) or 200mg (men) doses of mirabegron.

2. To determine if there is an interaction between (a) BMI and (b) age with respect to the capacity to increase BAT metabolic activity.

3. To describe the structural and physiological changes in the adipose tissue depots, including cell lineage, size, and inflammation.

4. To assess whether there are improvements in the liver, including reduced stiffness and quantity of hepatic fat.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
100
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Cohort 1MirabegronFemales taking 100 mg of mirabegron
Cohort 2AMirabegronMales taking 200 mg mirabegron
Cohort 2BB Complex Plus Vitamin C TabletsMales taking placebo drug
Cohort 3AMirabegronFemales taking 100 mg of mirabegron
Cohort 3BB Complex Plus Vitamin C TabletsFemales taking placebo drug
Primary Outcome Measures
NameTimeMethod
Cohorts 1 and 2: Change in BAT metabolic activity4 weeks

Change in brown adipose tissue (BAT) metabolic activity as measured by 18FFDG PET/CT

Cohort 3: Change in insulin sensitivity4 weeks

Change in glucose infusion rate, as measured by the hyperinsulinemic euglycemic clamp

Secondary Outcome Measures
NameTimeMethod
Identify changes in metabolic health arising from BAT activation and/or prolonged treatment with mirabegron4 weeks

Change in metabolic health parameters including body weight, fat mass, glucose tolerance, changes in levels of hormones, and improved liver function

Cohort 3: Changes in BAT metabolic activity4 weeks

Change in brown adipose tissue (BAT) metabolic activity as measured by 18FFDG PET/CT

Cohorts 1 and 2: Changes in insulin sensitivity4 weeks

Changes in glucose infusion rate, as measured by the hyperinsulinemic euglycemic clamp

Trial Locations

Locations (1)

National Institutes of Health Clinical Center

🇺🇸

Bethesda, Maryland, United States

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