Research
Hormonal
Brown Adipose Tissue (BAT) activity and adaptive thermogenesis are critically dependent on local Type 2 Deiodinase (D2) activity converting T4 to T3, particularly in response to cold exposure.
Exposure to cold can activate Brown Adipose Tissue (BAT), which burns calories to generate heat. This process relies on local thyroid hormone activation by the enzyme D2. While this is a potent metabolic lever, its impact varies significantly between individuals based on the amount of active BAT they possess.
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During cold exposure, the sympathetic nervous system induces D2 expression in brown adipocytes, thereby promoting local T4-to-T3 conversion, and activation of the transcription of target genes involved in the thermogenic program.
Why this rating
Supported by D2KO mouse models showing reduced UCP-1 and obesity resistance.
Source
Metabolic Effects of the Intracellular Regulation of Thyroid Hormone: Old Players, New Concepts
Annunziata Gaetana Cicatiello et al. · Frontiers in Endocrinology · 2018
DOI 10.3389/fendo.2018.00474
narrative_reviewCited 177×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Intracellular regulation of thyroid hormone by deiodinases (D1, D2, D3) dictates tissue-specific metabolic outcomes, where local T3 activation promotes energy expenditure and lipid mobilization, while inactivation preserves energy stores.Good
- Type 3 Deiodinase (D3) inactivation of thyroid hormone is essential for pancreatic beta-cell maturation and insulin secretion; D3 deficiency leads to glucose intolerance and impaired insulin secretion.Good
- Local thyroid hormone activation in skeletal muscle via D2 drives a shift from slow-twitch (Type I) to fast-twitch (Type II) fibers, increasing energy expenditure and influencing insulin sensitivity.Good
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