Effects of epinephrine and chemically related compounds on enzymatic deiodination of thyroxine, triiodothyronine, monoiodotyrosine and diiodotyrosine in vitro

Kobayashi, Isao; Yamada, Takashi; Shichijo, K

doi:10.1016/s0026-0495(66)80005-7

Cited by 5 publications

(2 citation statements)

References 25 publications

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“…It will be advantageous to deiodinate them as well, either by intracellular iodotyrosine/iodohistidine deiodinases or by enteric bacteria. Iodotyrosines are cleared rapidly from rat plasma (191), and potent iodotyrosine deiodinases occur in the liver and other extrathyroidal tissues of several mammals (192)(193)(194). It is of future interest to explore extrathyroidal enzyme systems for salvaging iodine from organic sources other than iodotyrosines or iodothyronines.…”

Section: Exogenous Thyroid Hormones and Sources Of Iodide For Salvagingmentioning

confidence: 99%

Iodine Metabolism and Thyroid-Related Functions in Organisms Lacking Thyroid Follicles: Are Thyroid Hormones also Vitamins?

Eales¹

1997

Experimental Biology and Medicine

135

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Thyroid-related functions in organisms devoid of follicular thyroid tissue have been reviewed. In the lamprey, a primitive vertebrate, the larva concentrates iodide and synthesizes thyroid hormones (TH) by iodoperoxidase (IP)-mediated iodination of a thyroglobulin (TG)-like molecule in a subpharyngeal afollicular endostyle. The endostyle is the thyroid homolog, and it reorganizes into a follicular thyroid at metamorphosis to the adult. Ascidians and amphloxus, invertebrate protochordate relatives of vertebrates, also concentrate iodide and synthesize TH in a subpharyngeal afollicular endostyle, but the endostyle never transforms to follicles. Ascidian plasma contains L-thyroxine and its more biologically active derivative 3,5,3'-triiodo-L-thyronine, and TH receptors exist, but TH effects are poorly understood. No other invertebrates possess an endostyle. Several invertebrates concentrate iodide at other sites and form protein-incorporated iodohistidines and iodotyrosines; however, de novo iodothyronine biosynthesis through IP-mediated TG iodination has not been established. Nevertheless, TH occur in invertebrates, and exogenous iodothyrosines or iodothyronines have effects on jellyfish, insects, and sea urchins. Furthermore, gut bacteria metabolize TH, and plants may synthesize TH by nonenzymatic oxidative iodination. Thus, TH occur in many organisms and, after ingestion and enteric absorption, can enter the food chain. Indeed, sea urchin larvae obtain TH required to induce metamorphosis from plant diatoms. Thyroid hormones can therefore have vitamin-like effects and, in conjunction with vitamin D, and possibly with other steroids, may be more aptly termed vitamones. Availability of exogenous TH has implications for models of invertebrate and vertebrate TH metabolism and iodine salvaging, and it may explain the prominent and probable ancestral role of peripheral mechanisms in regulating thyroidal status.

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Section: Exogenous Thyroid Hormones and Sources Of Iodide For Salvagingmentioning

confidence: 99%

Iodine Metabolism and Thyroid-Related Functions in Organisms Lacking Thyroid Follicles: Are Thyroid Hormones also Vitamins?

Eales¹

1997

Experimental Biology and Medicine

135

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“…The findings of Maclagan et al (29) underlined the reality of this suggestion. Epinephrine and chemically related compounds with two OH groups at the benzene ring inhibited deiodination of T 4 and T 3 in slices and homogenates of rat muscle and liver (31). Cortisol added to boiled and unboiled homogenates of rat liver, only inhibited T 4 deiodination in the unboiled preparations, suggesting an effect on enzymic deiodination (32).…”

Section: Deiodination Of Thyroid Hormonesmentioning

confidence: 97%

Notes on the History of Cellular Uptake and Deiodination of Thyroid Hormone

Hennemann¹

2005

Thyroid

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In this mini review on the history of the research devoted to thyroid hormone metabolism two pathways are discussed, i.e. uptake and subsequent deiodination in cells and tissues. In the 1950's the investigations of these processes were greatly stimulated when 131I became available for research purposes. The true nature of both mechanisms surfaced in the 1970's when it became apparent that transport of thyroid hormones into cells was a regulated carrier mediated process, while deiodination appeared to be catalyzed by different types of enzymes. Kinetic data indicated that these processes were of great importance in the ultimate regulation of thyroid hormone bio-availability.

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The relationship between ingested thyroid hormones, thyroid homeostasis and iodine metabolism in humans and teleost fish

Eales

2019

General and Comparative Endocrinology

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Effects of epinephrine and chemically related compounds on enzymatic deiodination of thyroxine, triiodothyronine, monoiodotyrosine and diiodotyrosine in vitro

Cited by 5 publications

References 25 publications

Iodine Metabolism and Thyroid-Related Functions in Organisms Lacking Thyroid Follicles: Are Thyroid Hormones also Vitamins?

Iodine Metabolism and Thyroid-Related Functions in Organisms Lacking Thyroid Follicles: Are Thyroid Hormones also Vitamins?

Notes on the History of Cellular Uptake and Deiodination of Thyroid Hormone

The relationship between ingested thyroid hormones, thyroid homeostasis and iodine metabolism in humans and teleost fish

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