Thyroid Hormone Activates Brown Adipose Tissue and Increases Non-Shivering Thermogenesis - A Cohort Study in a Group of Thyroid Carcinoma Patients

• Published in: PloS one Vol. 11; no. 1; p. e0145049
• Main Authors: Broeders, Evie P. M., Vijgen, Guy H. E. J., Havekes, Bas, Bouvy, Nicole D., Mottaghy, Felix M., Kars, Marleen, Schaper, Nicolaas C., Schrauwen, Patrick, Brans, Boudewijn, van Marken Lichtenbelt, Wouter D.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 19.01.2016; Public Library of Science (PLoS)
• Subjects: Adipocytes; Adipose tissue; Adipose tissue (brown); Adipose Tissue, Brown - drug effects; Adipose Tissue, Brown - metabolism; Adult; Blood pressure; Body fat; Brown adipose tissue; Cancer research; Cohort analysis; Correlation analysis; Diabetes; Energy; Energy expenditure; Exercise; Female; Health aspects; Hormones; Humans; Hyperthyroidism; Hypothyroidism; Iodine; Iodine radioisotopes; Kinases; Longitudinal studies; Male; Metabolic rate; Metabolism; Middle Aged; Non-shivering; Patients; Physical fitness; Physiological aspects; Physiology; Proteins; Receptors; Regression analysis; Rodents; Shivering; Surgery; Thermogenesis; Thermogenesis - drug effects; Thyroid; Thyroid cancer; Thyroid carcinoma; Thyroid hormone receptors; Thyroid hormones; Thyroid Hormones - administration & dosage; Thyroid Hormones - blood; Thyroid Hormones - pharmacology; Thyroid Neoplasms - metabolism; Thyroid-stimulating hormone; Thyroidectomy; Thyroxine
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0145049

Thyroid hormone receptors are present on brown adipose tissue (BAT), indicating a role for thyroid hormone in the regulation of BAT activation. The objective of this study was to examine the effect of thyroid hormone withdrawal followed by thyroid hormone in TSH-suppressive dosages, on energy expenditure and brown adipose tissue activity. This study was a longitudinal study in an academic center, with a follow-up period of 6 months. Ten patients with well-differentiated thyroid carcinoma eligible for surgical treatment and subsequent radioactive iodine ablation therapy were studied in a hypothyroid state after thyroidectomy and in a subclinical hyperthyroid state (TSH-suppression according to treatment protocol). Paired two-tailed t-tests and linear regression analyses were used. Basal metabolic rate (BMR) was significantly higher after treatment with synthetic thyroid hormone (levothyroxine) than in the hypothyroid state (BMR 3.8 ± 0.5 kJ/min versus 4.4 ± 0.6 kJ/min, P = 0.012), and non-shivering thermogenesis (NST) significantly increased from 15 ± 10% to 25 ± 6% (P = 0.009). Mean BAT activity was significantly higher in the subclinical hyperthyroid state than in the hypothyroid state (BAT standard uptake value (SUVMean) 4.0 ± 2.9 versus 2.4 ± 1.8, P = 0.039). Our study shows that higher levels of thyroid hormone are associated with a higher level of cold-activated BAT. ClinicalTrials.gov NCT02499471.