Topic
Thyroid hormone binding
About: Thyroid hormone binding is a research topic. Over the lifetime, 346 publications have been published within this topic receiving 12889 citations.
Papers published on a yearly basis
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Papers
TL;DR: The decline in serum T(3) and T(4) in models of acute illness precedes the fall in hepatic D1, suggesting that much of the initial fall in these hormones may be attributable to an acute phase response giving rise to a reduction in the thyroid hormone binding capacity of plasma.
Abstract: The mechanisms behind the changes in serum triiodothyronine (T(3)), thyroxine (T(4)) and TSH that occur in the non-thyroidal illness syndrome (NTIS) are becoming clearer. Induction of a central hypothyroidism occurs due to a diminution in hypothalamic thyrotropin-releasing hormone. This can be signalled by a decrease in leptin caused by malnutrition and possibly a localised increase in hypothalamic T(3) catalyzed by altered expression of hypothalamic iodothyronine deiodinases D2 and D3. Data from D1 and D2 knockout mice suggest that these enzymes may have little contribution to the low serum T(3) found in acute illness. The decline in serum T(3) and T(4) in models of acute illness precedes the fall in hepatic D1, suggesting that much of the initial fall in these hormones may be attributable to an acute phase response giving rise to a reduction in the thyroid hormone binding capacity of plasma. When measured by reliable methods, changes in serum free T(4) and free T(3) are modest in comparison to the fall seen in total thyroid hormone. Thyroid hormone transporter expression is up-regulated in many models of the NTIS, thus if diminished tissue uptake of hormone occurs in vivo, it is likely to be the result of impaired transporter function caused by diminished intracellular ATP or plasma inhibitors of transporter action. In man, chronic illness leads to an upregulation of thyroid hormone receptor (THR) expression at least in liver and renal failure. In contrast, human and animal models of sepsis and trauma indicate that expression of THRs and their coactivators are decreased in acute illness.
415 citations
TL;DR: Abundant evidence indicates that most if not all of the significant cellular responses regulated by the thyroid hormones are mediated by a cellular receptor localized to the cell nucleus.
Abstract: Publisher Summary This chapter describes the importance of thyroid hormones in the regulation of gene expression. Thyroid hormones have remarkable effect on differentiation and development in vertebrates. In man, for example, the lack of thyroid hormones can result in severe developmental deficiencies in the central nervous and skeletal systems. Thyroid hormones also have noticeable influence on metabolism in adults. The studies so far specify that hormones influence a number of gene products; in fact, changes in the levels of certain proteins and enzymes are known to account at least in part, for particular physiological responses to the hormone. Additionally, the finding of intranuclear receptors whose characteristics are suggestive of their involvement in thyroid responses has also directed attention to the nucleus as a potential site of thyroid hormone regulation. The chapter also describes thyroid hormone binding components in other cellular fractions. High-affinity and limited-capacity thyroid hormone binding components have also been identified in the cytosol, mitochondria, and membrane fractions. The properties of the cytosol binders have shown considerable variation as reported in different tissues. For example, the cytosol binding proteins in cultured pituitary cells have a higher affinity for thyroxine than for triiodothyronine.
322 citations
TL;DR: Whether patients with nonthyroidal illnesses with low T4 or T3, or both, are hypothyroid is uncertain; concentrations of free T4 have been estimated as low, normal, or high using different methods.
Abstract: Alterations in thyroid physiology and thyroid function tests occur in some patients with nonthyroidal illnesses. Low concentrations of serum triiodothyronine (T3) usually occur in nonthyroidal illnesses and are attributable largely to reduced extrathyroidal conversion of thyroxine (T4) to T3. Concentrations of serum total T4 may be low, normal, or high; alterations in serum binding of T4 explain the abnormality in most cases. Concentrations of serum reverse T3 are usually high because metabolic clearance is reduced. Whether patients with nonthyroidal illnesses with low T4 or T3, or both, are hypothyroid is uncertain; concentrations of free T4 have been estimated as low, normal, or high using different methods. Serum thyroid-stimulating hormone is typically normal. Low concentrations of T3 or T4, or both, in nonthyroidal illnesses may have a homeostatic significance. Low serum concentrations of T4 correlate with poor prognosis in nonthyroidal illnesses. Inhibitors of thyroid hormone binding and phagocytosis are present in normal tissues. Leakage of the inhibitors into the circulation may lower serum concentrations of T4 on one hand and compromise critical host defenses on the other.
314 citations
TL;DR: Protein modelling studies are presented that demonstrate differences in the electrostatic characteristics of the molecule in human, rat, chicken, and fish, which may explain why, in contrast to TTR from human and rat, T TR from fish and birds preferentially binds triiodo-l-thyronine.
227 citations
TL;DR: High resolution X-ray analysis of the hormone-binding protein pre albumin has shown that it has a structural complementarity to double-helical DNA, suggesting prealbumin as a model for the thyroid hormone nuclear receptor, providing a number of detailed predictions of its properties.
Abstract: High resolution X-ray analysis of the hormone-binding protein prealbumin has shown that it has a structural complementarity to double-helical DNA The proposed binding site is composed of two symmetry-related β-sheets containing a pair of helically disposed arms, which can interact with the bases in the wide groove of DNA A palindromic target sequence is indicated by the symmetry of the protein The two identical thyroid hormone binding sites on prealbumin are located in a channel that runs completely through the molecule These two structural features suggest prealbumin as a model for the thyroid hormone nuclear receptor, providing a number of detailed predictions of its properties
221 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 2 |
| 2020 | 2 |
| 2019 | 4 |
| 2018 | 5 |
| 2017 | 3 |
| 2016 | 2 |