Dataset Information

Resolution of Hypothyroidism Restores Cold-Induced Thermogenesis in Humans.

ABSTRACT: BACKGROUND:Hypothyroidism is a frequent endocrine disorder with common symptoms of increased cold sensitivity and unintended weight gain, indicating changes in energy expenditure (EE) and response to cold exposure. Thyroid hormones (TH) play an important role for proper function of brown adipose tissue (BAT) and cold-induced thermogenesis (CIT) in rodents, but the role of hypothyroidism on CIT in humans is uncertain. METHODS:This was a prospective observational study. Forty-two patients presenting with subclinical or overt hypothyroidism in whom TH replacement was planned were recruited. Thirty-three patients completed the study. Thermogenesis was measured by indirect calorimetry during warm conditions and after a mild cold stimulus of 90 minutes, both during the hypothyroid state and after at least three months of sufficient TH replacement. CIT was determined as the difference between EE during mildly cold and warm conditions. The primary endpoint was the change of CIT between the hypothyroid and euthyroid state. RESULTS:EE during warm conditions increased from a median of 1330 (interquartile range [IQR] 1251-1433) kcal/24 hours in the hypothyroid state to a median of 1442 (IQR 1294-1579) kcal/24 hours in the euthyroid state (+8.5%; p?=?0.0002). EE during mild cold exposure increased from 1399 (IQR 1346-1571) kcal/24 hours to 1610 (IQR 1455-1674) kcal/24 hours (+15%; p?

SUBMITTER: Maushart CI

PROVIDER: S-EPMC6482913 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Resolution of Hypothyroidism Restores Cold-Induced Thermogenesis in Humans.

Maushart Claudia Irene CI Loeliger Rahel R Gashi Gani G Christ-Crain Mirjam M Betz Matthias Johannes MJ

Thyroid : official journal of the American Thyroid Association 20190308 4

<h4>Background</h4>Hypothyroidism is a frequent endocrine disorder with common symptoms of increased cold sensitivity and unintended weight gain, indicating changes in energy expenditure (EE) and response to cold exposure. Thyroid hormones (TH) play an important role for proper function of brown adipose tissue (BAT) and cold-induced thermogenesis (CIT) in rodents, but the role of hypothyroidism on CIT in humans is uncertain.<h4>Methods</h4>This was a prospective observational study. Forty-two pa ...[more]

PMID: 30724123

Similar Datasets

Project description:CONTEXT:The contribution of brown adipose tissue (BAT) to the energy balance in humans exposed to sustainable cold has not been completely established, partially because of measurement limitations of both BAT activity and energy expenditure (EE). OBJECTIVE:The objective of the study was to characterize the role of BAT activation in cold-induced thermogenesis (CIT). DESIGN:This study was a single-blind, randomized crossover intervention. SETTING:The study was conducted at the National Institutes of Health Clinical Center. STUDY PARTICIPANTS:Thirty-one healthy volunteers participated in the study. INTERVENTIONS:The intervention included mild cold exposure. MAIN OUTCOMES:CIT and BAT activation were the main outcomes in this study. METHODS:Overnight EE measurement by whole-room indirect calorimeter at 24 °C or 19 °C was followed by 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (PET) scan. After 36 hours, volunteers crossed over to the alternate study temperature under identical conditions. BAT activity was measured in a 3-dimensional region of interest in the upper torso by comparing the uptake at the two temperatures. RESULTS:Twenty-four volunteers (14 males, 10 females) had a complete data set. When compared with 24 °C, exposure at 19 °C resulted in increased EE (5.3 ± 5.9%, P < .001), indicating CIT response and mean BAT activity (10.5 ± 11.1%, P < .001). Multiple regression analysis indicated that a difference in BAT activity (P < .001), age (P = .01), and gender (P = .037) were independent contributors to individual variability of CIT. CONCLUSIONS:A small reduction in ambient temperature, within the range of climate-controlled buildings, is sufficient to increase human BAT activity, which correlates with individual CIT response. This study uncovers for the first time a spectrum of BAT activation among healthy adults during mild cold exposure not previously recognized by conventional PET and PET-computed tomography methods. The enhancement of cold-induced BAT stimulation may represent a novel environmental strategy in obesity treatment.

Dataset Information

Resolution of Hypothyroidism Restores Cold-Induced Thermogenesis in Humans.

Publications

Resolution of Hypothyroidism Restores Cold-Induced Thermogenesis in Humans.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets