Thyroid hormone receptor beta 2 (TRβ2)

Thyroid hormone receptor beta 2 (TRβ2) is a specific isoform of the THRB gene, a member of the nuclear receptor superfamily that functions as a ligand-dependent transcription factor (UniProt P10828). It is primarily expressed in the hypothalamus and pituitary gland, where it mediates the negative feedback of thyroid hormones on TSH and TRH production (PMID: 11443170). Additionally, TRβ2 is essential for the proper development of the retina and cochlea, specifically influencing cone photoreceptor differentiation (PMID: 15545624). In the liver, TRβ activation promotes the breakdown of triglycerides and the clearance of cholesterol, making it a high-value target for metabolic disorders (PMID: 30104244). Drugs like Resmetirom have been developed to selectively target TRβ over TRα to treat metabolic dysfunction-associated steatohepatitis (MASH) without causing cardiac side effects (FDA, 2024). Mutations in the THRB gene, including those affecting the TRβ2 isoform, can lead to Resistance to Thyroid Hormone (RTH) syndrome, characterized by elevated thyroid hormones and non-suppressed TSH (NCBI Gene ID: 7068). Therapeutic strategies focusing on TRβ2 agonism aim to restore metabolic balance in patients with fatty liver disease and dyslipidemia. The selectivity of these agents is crucial, as non-selective activation of thyroid receptors leads to thyrotoxicosis and bone loss.

Other names

THRB2NR1A2Nuclear receptor subfamily 1 group A member 2ERBA2GRTHTHR-beta-2

Selective agonism of the thyroid hormone receptor beta isoform to stimulate hepatic lipid metabolism and reduce systemic cholesterol levels while minimizing alpha-isoform-mediated cardiac and skeletal side effects.