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Fokina EF, Shpakov AO. Thyroid-Stimulating Hormone Receptor: the Role in the Development of Thyroid Pathology and Its Correction. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022050143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abstract
One of the key elements responsible for the thyroid response
to thyroid-stimulating hormone (TSH) is the TSH receptor (TSHR),
which belongs to the G protein-coupled receptor superfamily. Binding
of TSH or stimulatory autoantibodies to the TSHR extracellular domain
triggers multiple signaling pathways in target cells that are mediated
through various types of G proteins and β-arrestins. Inhibitory
autoantibodies, in contrast, suppress TSHR activity, inducing hypothyroid states.
Activating mutations lead to constitutively active TSHR forms and
can trigger cancer. Therefore, the TSHR is one of the key targets
for the regulation of thyroid function and thyroid status, as well
as correction of diseases caused by changes in TSHR activity (autoimmune
hyper- and hypothyroidism, Graves’ ophthalmopathy, thyroid cancer).
TSH preparations are extremely rarely used in medicine due to their
immunogenicity and severe side effects. Most promising is the development
of low-molecular allosteric TSHR regulators with an activity of
full and inverse agonists and neutral antagonists, which are able
to penetrate into the allosteric site located in the TSHR transmembrane
domain and specifically bind to it, thus controlling the ability
of the receptor to interact with G proteins and β-arrestins. Allosteric
regulators do not affect the binding of TSH and autoantibodies to
the receptor, which enables mild and selective regulation of thyroid function,
while avoiding critical changes in TSH and thyroid hormone levels.
The present review addresses the current state of the problem of
regulating TSHR activity, including the possibility of using ligands
of its allosteric sites.
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Li Z, Muench G, Wenhart C, Goebel S, Reimann A. Definition of a sectioning plane and place for a section containing hoped-for regions using a spare counterpart specimen. Sci Rep 2022; 12:13342. [PMID: 35922656 PMCID: PMC9349253 DOI: 10.1038/s41598-022-17380-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 07/25/2022] [Indexed: 11/22/2022] Open
Abstract
Histological examination of targets in regions of interest in histological sections is one of the most frequently used tools in biomedical research. However, it is a technical challenge to secure a multitarget section for inspection of the structure’s mutual relationship of targets or a longitudinally filamentous- or tubular-formed tissue section for visitation of the overall morphological features. We present a method with a specified cutting plane and place, allowing researchers to cut directly at the multitarget centers accurately and quickly. The method is proven to be reliable with high accuracy and reproducibility and a low coefficient of variation, testing on repeat experiments of three target’s position-known models. With this method, we successfully yielded single sections containing whole intraorbital optical nerves, three aortic valves, or whole thoracic tracheas in their central positions. The adjoined custom-made tools used in the study, such as various tissue-specific formulated calibrated trimming and embedding guides, an organ-shaped cavity plaster mold, and a two-time embedding technique for optimal and identical trimming or embedding, also bear great potential to become a common supplemental tool for traditional histology and may contribute to the reduction of the labor, and the number of animals needed.
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Affiliation(s)
- Zhongmin Li
- Advancecor GmbH, Lochhamerstr. 29 A, 82152, Martinsried, Germany.
| | - Goetz Muench
- Advancecor GmbH, Lochhamerstr. 29 A, 82152, Martinsried, Germany
| | - Clara Wenhart
- Advancecor GmbH, Lochhamerstr. 29 A, 82152, Martinsried, Germany
| | - Silvia Goebel
- Advancecor GmbH, Lochhamerstr. 29 A, 82152, Martinsried, Germany
| | - Andreas Reimann
- Advancecor GmbH, Lochhamerstr. 29 A, 82152, Martinsried, Germany
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Tagami T, Moriyama K. Characterization of apparently paradoxical thyrotropin binding inhibitory immunoglobulins with neutral bioactivity. J Endocr Soc 2022; 6:bvac070. [PMID: 35611323 PMCID: PMC9123305 DOI: 10.1210/jendso/bvac070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Indexed: 11/24/2022] Open
Abstract
Context The thyrotropin (TSH) receptor (TSH-R) autoantibody activity is clinically measured by inhibition of labeled ligand (TSH or M22) binding to the TSH-R (TSH-binding inhibitory immunoglobulin [TBII]) or by stimulation (TSH-R stimulating antibody [TSAb]) or inhibition (TSH-R blocking antibody [TSBAb]) of 3′,5′-cyclic adenosine 5′-monophosphate (cAMP) production in isolated cells. Objective We experienced a patient with hypothyroid Graves disease (GD) having strong positive TBII but with almost neutral bioactivities on the TSH-R. The aim of this study is the characterization of this apparently paradoxical TBII (serum sample S). Methods We first compared the TBII, TSAb, and TSBAb activities of serum sample S with mixtures of stimulating (S-mAb) and blocking monoclonal Ab (B-mAb). Next, we serially measured cAMPs stimulated by various serum samples in the presence or absence of TSH. Results Mixtures of S-mAb and B-mAb did not reproduce the characteristics of serum sample S. Instead, serum sample S had a unique feature that blocked the TSH-stimulated cAMP initially but disappeared the blocking activity thereafter to reach the control level. Conclusion We present here the TBIIs with neutral bioactivities found in the patient with autoimmune thyroid disease, which strongly inhibit TSH binding to the TSH-R but exerts neither TSAb nor TSBAb activity. Differences in the methods of detecting TRAb between TBII in vitro and bioassay may cause the discrepancy. Although serum sample S may be an extreme example, a variety of TRAb that not only stimulates or blocks but also interferes with TSH-R binding for only a short time may exist in the serum samples of GD patients.
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Affiliation(s)
- Tetsuya Tagami
- Department of Endocrinology and Metabolism, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
- Clinical Research Institute for Endocrine and Metabolic Diseases, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
| | - Kenji Moriyama
- Department of Medicine and Clinical Science, Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Hyogo, Japan
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Coscia F, Taler-Verčič A. Cryo-EM: A new dawn in thyroid biology. Mol Cell Endocrinol 2021; 531:111309. [PMID: 33964321 PMCID: PMC8316605 DOI: 10.1016/j.mce.2021.111309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/25/2021] [Accepted: 04/27/2021] [Indexed: 11/09/2022]
Abstract
The thyroid gland accumulates the rare dietary element iodine and incorporates it into iodinated thyroid hormones, utilising several tightly regulated reactions and molecular mechanisms. Thyroid hormones are essential in vertebrates and play a central role in many biological processes, such as development, thermogenesis and growth. The control of these functions is exerted through the binding of hormones to nuclear thyroid hormone receptors that rule the transcription of numerous metabolic genes. Over the last 50 years, thyroid biology has been studied extensively at the cellular and organismal levels, revealing its multiple clinical implications, yet, a complete molecular understanding is still lacking. This includes the atomic structures of crucial pathway components that would be needed to elucidate molecular mechanisms. Here we review the currently known protein structures involved in thyroid hormone synthesis, regulation, transport, and actions. We also highlight targets for future investigations that will significantly benefit from recent advances in macromolecular structure determination by electron cryo-microscopy (cryo-EM). As an example, we demonstrate how cryo-EM was crucial to obtain the structure of the large thyroid hormone precursor protein, thyroglobulin. We discuss modern cryo-EM compared to other structure determination methods and how an integrated structural and cell biological approach will help filling the molecular knowledge gap in our understanding of thyroid hormone metabolism. Together with clinical, cellular and high-throughput 'omics' studies, atomic structures of thyroid components will provide an important framework to map disease mutations and to interpret and predict thyroid phenotypes.
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Affiliation(s)
- Francesca Coscia
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK; Human Technopole, Via Cristina Belgioioso 171, 20157, Milano, Italy.
| | - Ajda Taler-Verčič
- University of Ljubljana, Faculty of Medicine, Institute of Biochemistry and Molecular Genetics, Vrazov Trg 2, 1000, Ljubljana, Slovenia
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D'Aurizio F. The role of laboratory medicine in the diagnosis of the hyperthyroidism. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF RADIOPHARMACEUTICAL CHEMISTRY AND BIOLOGY 2021; 65:91-101. [PMID: 33565846 DOI: 10.23736/s1824-4785.21.03344-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hyperthyroidism is a clinical condition characterized by inappropriately high synthesis and secretion of thyroid hormones by the thyroid gland. It has multiple aetiologies, manifestations and potential therapies. Graves' disease is the most common form of hyperthyroidism, due to the production of autoantibodies against thyrotropin receptor, capable of over-stimulating thyroid function. A reliable diagnosis of hyperthyroidism can be established on clinical grounds, followed by the evaluation of serum thyroid function tests (thyrotropin first and then free thyroxine, adding the measurement of free triiodothyronine in selected specific situations). The recent guidelines of both the American and European Thyroid Associations have strongly recommended the measurement of thyrotropin receptor autoantibodies for the accurate diagnosis and management of Graves' disease. If autoantibody test is negative, a radioiodine uptake should be performed. Considering the most recent laboratory improvements, binding assays can be considered the best first solution for the measurement of thyrotropin receptor autoantibodies in diagnosis and management of overt cases of Graves' disease. In fact, they have a satisfactory clinical sensitivity and specificity (97.4% and 99.2%, respectively) being performed in clinical laboratories on automated platforms together with the other thyroid function tests. In this setting, the bioassays should be reserved for fine and complex diagnoses and for particular clinical conditions where it is essential to document the transition from stimulating to blocking activity or vice versa (e.g. pregnancy and post-partum, related thyroid eye disease, Hashimoto's thyroiditis with extrathyroidal manifestations, unusual cases after LT4 therapy for hypothyroidism or after antithyroid drug treatment for Graves' disease). Undoubtedly, technological advances will help improve laboratory diagnostics of hyperthyroidism. Nevertheless, despite future progress, the dialogue between clinicians and laboratory will continue to be crucial for an adequate knowledge and interpretation of the laboratory tests and, therefore, for an accurate diagnosis and correct management of the patient.
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Affiliation(s)
- Federica D'Aurizio
- Department of Laboratory Medicine, Institute of Clinical Pathology, Santa Maria della Misericordia University Hospital, Udine, Italy -
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Davies TF, Andersen S, Latif R, Nagayama Y, Barbesino G, Brito M, Eckstein AK, Stagnaro-Green A, Kahaly GJ. Graves' disease. Nat Rev Dis Primers 2020; 6:52. [PMID: 32616746 DOI: 10.1038/s41572-020-0184-y] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/19/2020] [Indexed: 02/08/2023]
Abstract
Graves' disease (GD) is an autoimmune disease that primarily affects the thyroid gland. It is the most common cause of hyperthyroidism and occurs at all ages but especially in women of reproductive age. Graves' hyperthyroidism is caused by autoantibodies to the thyroid-stimulating hormone receptor (TSHR) that act as agonists and induce excessive thyroid hormone secretion, releasing the thyroid gland from pituitary control. TSHR autoantibodies also underlie Graves' orbitopathy (GO) and pretibial myxoedema. Additionally, the pathophysiology of GO (and likely pretibial myxoedema) involves the synergism of insulin-like growth factor 1 receptor (IGF1R) with TSHR autoantibodies, causing retro-orbital tissue expansion and inflammation. Although the aetiology of GD remains unknown, evidence indicates a strong genetic component combined with random potential environmental insults in an immunologically susceptible individual. The treatment of GD has not changed substantially for many years and remains a choice between antithyroid drugs, radioiodine or surgery. However, antithyroid drug use can cause drug-induced embryopathy in pregnancy, radioiodine therapy can exacerbate GO and surgery can result in hypoparathyroidism or laryngeal nerve damage. Therefore, future studies should focus on improved drug management, and a number of important advances are on the horizon.
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Affiliation(s)
- Terry F Davies
- Thyroid Research Laboratory, Icahn School of Medicine at Mount Sinai, New York, NY, USA. .,James J. Peters VA Medical Center, New York, NY, USA. .,Mount Sinai Thyroid Center, Mount Sinai Downtown at Union Sq, New York, NY, USA.
| | - Stig Andersen
- Department of Geriatric and Internal Medicine and Arctic Health Research Center, Aalborg University Hospital, Aalborg, Denmark
| | - Rauf Latif
- Thyroid Research Laboratory, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,James J. Peters VA Medical Center, New York, NY, USA
| | - Yuji Nagayama
- Department of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Giuseppe Barbesino
- Thyroid Unit, Division of Endocrinology, Massachusetts General Hospital, Boston, MA, USA
| | - Maria Brito
- Mount Sinai Thyroid Center, Mount Sinai Downtown at Union Sq, New York, NY, USA
| | - Anja K Eckstein
- Department of Ophthalmology, University Duisburg Essen, Essen, Germany
| | - Alex Stagnaro-Green
- Departments of Medicine, Obstetrics and Gynecology and Medical Education, University of Illinois College of Medicine at Rockford, Rockford, IL, USA
| | - George J Kahaly
- Department of Medicine I, Johannes Gutenberg University Medical Centre, Mainz, Germany
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Tozzoli R. Receptor autoimmunity: diagnostic and therapeutic implications. AUTO- IMMUNITY HIGHLIGHTS 2020; 11:1. [PMID: 32127047 PMCID: PMC7065331 DOI: 10.1186/s13317-019-0125-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 12/26/2019] [Indexed: 12/21/2022]
Abstract
Receptor autoimmunity is one of the ways in which autoimmune diseases appear in humans. Graves' disease, myasthenia gravis, idiopathic membranous nephropathy, and autoimmune acute encephalitis are the major autoimmune diseases belonging to this particular group. Receptor autoimmune disease are dependent on the presence of autoantibodies directed against cell-surface antigens, namely TSH receptor in thyrocytes, acetylcholine receptor in neuromuscular junction, phospholipase 2 receptor in podocytes, and NMDA receptor in cortical neurons. In this article we outline the distinctive features of receptor autoimmunity and the specific relationship between the autoimmunology laboratory and the presence/concentration of autoantibodies. Some immunological features distinguish receptor autoimmunity. Anti-receptor autoantibody pathologies are considered T cell-dependent, B-cell-mediated autoimmune disorders: the knowledge about the presence of circulating and/or localized autoantibodies to target organs and identification of autoantigens involved in the autoimmune reaction is of paramount importance. Due to the close correlation between the concentration of anti-receptor autoantibodies, the autoimmune target of some cell-surface receptors and the intensity of symptoms, the measurement of these immunoglobulins has become central to diagnose autoimmune diseases in all affected patients, not just in clinically dubious cases. The measurement of autoantibodies is also relevant for differential diagnosis of autoimmune and non-autoimmune forms with similar symptoms. From the methodological point of view, quantitative immunoassay methods of measurement should be preferred over semi-quantitative ones, for the capacity of the first class of methods to define precisely the reference ranges and decision levels overcoming the measurement uncertainty of semi-quantitative methods.
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Affiliation(s)
- Renato Tozzoli
- Laboratory of Clinical Pathology, S. Maria degli Angeli Hospital, and Consultant Endocrinologist, San Giorgio Clinics, Pordenone, Italy.
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