Adaptive activation of thyroid hormone and energy expenditure

Biosci Rep. Jun-Aug 2005;25(3-4):191-208. doi: 10.1007/s10540-005-2885-6.


The mechanisms by which thyroid hormone accelerates energy expenditure are poorly understood. In the brown adipose tissue (BAT), activation of thyroid hormone by type 2 iodothyronine deiodinase (D2) has been known to play a role in adaptive energy expenditure during cold exposure in human newborns and other small mammals. Although BAT is not present in significant amounts in normal adult humans, recent studies have found substantial amounts of D2 in skeletal muscle, a metabolically relevant tissue in humans. This article reviews current biological knowledge about D2 and adaptive T3 production and their roles in energy expenditure.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Acclimatization / physiology*
  • Adipose Tissue, Brown / metabolism
  • Animals
  • Body Temperature Regulation
  • Cold Temperature
  • Energy Metabolism*
  • Hot Temperature
  • Humans
  • Iodide Peroxidase / genetics
  • Iodide Peroxidase / metabolism
  • Muscle, Skeletal / metabolism
  • Thermogenesis / physiology
  • Thyroid Gland / metabolism
  • Thyroid Hormones / metabolism*


  • Thyroid Hormones
  • iodothyronine deiodinase type II
  • Iodide Peroxidase