Minireview: 3-Iodothyronamine (T1AM): a new player on the thyroid endocrine team? - PubMed (original) (raw)

Review

. 2009 Mar;150(3):1108-11.

doi: 10.1210/en.2008-1596. Epub 2008 Dec 30.

Affiliations

Review

Minireview: 3-Iodothyronamine (T1AM): a new player on the thyroid endocrine team?

Thomas S Scanlan. Endocrinology. 2009 Mar.

Abstract

3-Iodothyronamine (T(1)AM) is an endogenous compound with chemical features that are similar to thyroid hormone. T(1)AM has a carbon skeleton identical to that of T(4) and contains a single carbon-iodine bond. Theoretically, T(1)AM could be produced from T(4) by enzymatic decarboxylation and deiodination. Recent studies show that T(1)AM and higher iodinated thyronamines are subject to similar metabolic processing as iodothyronines such as T(4), suggesting a biological linkage between iodothyronines and iodothyronamines. In addition, single doses of T(1)AM administered to rodents induce a hypometabolic state that in certain ways resembles hibernation and is opposite to the effects of excess T(4). This review will discuss the latest developments on this recently discovered thyroid hormone derivative.

PubMed Disclaimer

Figures

Figure 1

Figure 1

The chemical structures of thyronines and thyronamines. T4 is converted to both T3 and rT3 by the indicated deiodinases. T1AM, the most studied thyronamine to date, has the same chemical skeleton as T4 and theoretically can be made from T4 by enzymatic decarboxylation and deiodination.

Figure 2

Figure 2

Summary of enzyme-catalyzed thyronamine deiodinase reactions. Unlike T4, T4AM is not a substrate for Dio1 and -2 and cannot be deiodinated to T3AM. However, T4AM is readily deiodinated to rT3AM by Dio3, and rT3AM can be further deiodinated to ultimately provide T1AM. This suggests a unique biosynthetic deiodination pathway for T1AM starting from the decarboxylation products of either T4 or rT3.

References

    1. Yen PM 2001 Physiological and molecular basis of thyroid hormone action. Physiol Rev 81:1097–1142 - PubMed
    1. Kohrle J 2002 Iodothyronine deiodinases. Methods Enzymol 347:125–167 - PubMed
    1. Bianco A, Kim BW 2006 Deiodinases: implications of the local control of thyroid hormone action. J Clin Invest 116:2571–2579 - PMC - PubMed
    1. Huang SA 2005 Physiology and pathophysiology of type 3 deiodinase in humans. Thyroid 15:875–881 - PubMed
    1. Pittman CS 1979 Hormone metabolism. In: DeGroot LJ, ed. Endocrinology. 1st ed. New York: Grune, Stratton; 365–372

Publication types

MeSH terms

Substances

LinkOut - more resources