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Lanzolla G, Marinò M, Menconi F. Graves disease: latest understanding of pathogenesis and treatment options. Nat Rev Endocrinol 2024:10.1038/s41574-024-01016-5. [PMID: 39039206 DOI: 10.1038/s41574-024-01016-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/20/2024] [Indexed: 07/24/2024]
Abstract
Graves disease is the most common cause of hyperthyroidism in iodine-sufficient areas. The main responsible mechanism is related to autoantibodies that bind and activate the thyrotropin receptor (TSHR). Although Graves hyperthyroidism is relatively common, no causal treatment options are available. Established treatment modalities are antithyroid drugs, which reduce thyroid hormone synthesis, radioactive iodine and surgery. However, emerging drugs that target the main autoantigen (monoclonal antibodies, small molecules, peptides) or block the immune pathway have been recently tested in clinical trials. Graves disease can involve the thyroid exclusively or it can be associated with extrathyroidal manifestations, among which Graves orbitopathy is the most common. The presence of Graves orbitopathy can change the management of the disease. An established treatment for moderate-to-severe Graves orbitopathy is intravenous glucocorticoids. However, recent advances in understanding the pathogenesis of Graves orbitopathy have allowed the development of new target-based therapies by blocking pro-inflammatory cytokine receptors, lymphocytic infiltration or the insulin-like growth factor 1 receptor (IGF1R), with several clinical trials providing promising results. This article reviews the new discoveries in the pathogenesis of Graves hyperthyroidism and Graves orbitopathy that offer several important tools in disease management.
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Affiliation(s)
- Giulia Lanzolla
- Department of Clinical and Experimental Medicine, Endocrinology Unit II, University of Pisa and University Hospital of Pisa, Pisa, Italy
- Department of Orthopaedic Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Michele Marinò
- Department of Clinical and Experimental Medicine, Endocrinology Unit II, University of Pisa and University Hospital of Pisa, Pisa, Italy
| | - Francesca Menconi
- U.O. Endocrinologia II, Azienda Ospedaliero Universitaria Pisana, University Hospital of Pisa, Pisa, Italy.
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Hu C, Xu Y, Wang M, Cui S, Zhang H, Lu L. Bisphenol analogues induce thyroid dysfunction via the disruption of the thyroid hormone synthesis pathway. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:165711. [PMID: 37487893 DOI: 10.1016/j.scitotenv.2023.165711] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/02/2023] [Accepted: 07/20/2023] [Indexed: 07/26/2023]
Abstract
Bisphenol analogues are widely used in industrial and daily-use consumer products having imperfect thyroid hormones (THs) structures. Widespread exposure interferes with thyroid-related health outcomes in human. The mechanisms of disruption on TH synthesis and subsequent thyroid dysfunction by different bisphenol analogues remain unclear. Here, we evaluated bisphenol-induced thyroid endocrine disruption in C57BL/6 mice at doses of 0.002, 0.02, 2, and 20 mg/kg body weight/day (BW/d) for five consecutive weeks. Administration of 20 mg/kg BW/d bisphenol S (BPS) and 2 mg/kg BW/d tetrabromobisphenol S (TBBPS) significantly increased serum thyrotropin (TSH) levels to 1.21-fold and 1.20-fold of control group, respectively, indicating that bisphenols induced thyroid dysfunction in mice. Height of the thyroid follicle epithelium significantly increased to 1.27-, 1.24-, 1.26-, and 1.36-fold compared to control group with BPA, BPS, TBBPA, and TBBPS at 20 mg/kg BW/d, respectively, indicating impairment of the thyroid gland structure, and TBBPS showed potent effect. Exposure to bisphenol analogues of 0.02 mg/kg BW/d downregulated the protein expression levels of thyrotropin receptor, the sodium/iodide symporter, thyroperoxidase. The TH-dependent effects were further determined using the T-Screen assay at 10-11 M to 10-5 M concentrations. Bisphenol analogues significantly decreased TH-dependent GH3 cell proliferation, indicating the antagonistic activity of bisphenol analogues. The gene responsible for THs synthesis of thyrotropin releasing hormone receptor and TSH were upregulated, but downregulation of thyroid receptor β was observed. Our results suggest that bisphenol analogues distinctly induce thyroid dysfunction via TH synthesis, implying adverse effect of bisphenol analogues on TH homeostasis and subsequent physiological processes.
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Affiliation(s)
- Chao Hu
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China; School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China; School of Engineering, Hangzhou Normal University, Hangzhou 310018, China
| | - Yeqing Xu
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
| | - Mingmin Wang
- The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Shixuan Cui
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hangjun Zhang
- School of Engineering, Hangzhou Normal University, Hangzhou 310018, China; Hangzhou International Urbanology Research Center, Hangzhou 311121, China
| | - Liping Lu
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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Zala A, Thomas R. Antigen-specific immunotherapy to restore antigen-specific tolerance in Type 1 diabetes and Graves' disease. Clin Exp Immunol 2023; 211:164-175. [PMID: 36545825 PMCID: PMC10019129 DOI: 10.1093/cei/uxac115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 10/23/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Type 1 diabetes and Graves' disease are chronic autoimmune conditions, characterized by a dysregulated immune response. In Type 1 diabetes, there is beta cell destruction and subsequent insulin deficiency whereas in Graves' disease, there is unregulated excessive thyroid hormone production. Both diseases result in significant psychosocial, physiological, and emotional burden. There are associated risks of diabetic ketoacidosis and hypoglycaemia in Type 1 diabetes and risks of thyrotoxicosis and orbitopathy in Graves' disease. Advances in the understanding of the immunopathogenesis and response to immunotherapy in Type 1 diabetes and Graves' disease have facilitated the introduction of targeted therapies to induce self-tolerance, and subsequently, the potential to induce long-term remission if effective. We explore current research surrounding the use of antigen-specific immunotherapies, with a focus on human studies, in Type 1 diabetes and Graves' disease including protein-based, peptide-based, dendritic-cell-based, and nanoparticle-based immunotherapies, including discussion of factors to be considered when translating immunotherapies to clinical practice.
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Affiliation(s)
- Aakansha Zala
- Frazer Institute, The University of Queensland, Princess Alexandra Hospital, Woolloongabba, QLD, Australia
| | - Ranjeny Thomas
- Correspondence: Ranjeny Thomas, Frazer Institute, The University of Queensland.
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Casasanta NA, Shah N, Troy K, Edwards C, Patel RB. Presentation of concurrent thrombotic thrombocytopenic purpura and Graves' disease. Blood Coagul Fibrinolysis 2022; 33:422-424. [PMID: 35867945 DOI: 10.1097/mbc.0000000000001154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a type of thrombotic microangiopathy caused by deficient activity of ADAMTS13 that most commonly occurs secondary to an acquired autoantibody. There are limited data on the association between TTP and autoimmune thyroid disease. We present a case of acquired TTP in the setting of thyrotoxicosis from Graves' disease. Our patient improved with standard treatment of both TTP and thyrotoxicosis. A retrospective review of patients with TTP at our institution demonstrated that 32% had another autoimmune disorder, highlighting the concept of polyautoimmunity. These findings suggest an association between TTP and uncontrolled autoimmune disease. In patients with newly diagnosed TTP, physicians should evaluate for other autoimmune diseases and check thyroid function tests.
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Affiliation(s)
| | - Nirali Shah
- Division of Endocrinology, Diabetes, and Bone Disease
| | - Kevin Troy
- Division of Hematology and Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Colleen Edwards
- Division of Hematology and Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Rima B Patel
- Division of Hematology and Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Draman MS, Zhang L, Dayan C, Ludgate M. Orbital Signaling in Graves' Orbitopathy. Front Endocrinol (Lausanne) 2021; 12:739994. [PMID: 34899596 PMCID: PMC8660111 DOI: 10.3389/fendo.2021.739994] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/21/2021] [Indexed: 11/13/2022] Open
Abstract
Graves' orbitopathy (GO) is a complex and poorly understood disease in which extensive remodeling of orbital tissue is dominated by adipogenesis and hyaluronan production. The resulting proptosis is disfiguring and underpins the majority of GO signs and symptoms. While there is strong evidence for the thyrotropin receptor (TSHR) being a thyroid/orbit shared autoantigen, the insulin-like growth factor 1 receptor (IGF1R) is also likely to play a key role in the disease. The pathogenesis of GO has been investigated extensively in the last decade with further understanding of some aspects of the disease. This is mainly derived by using in vitro and ex vivo analysis of the orbital tissues. Here, we have summarized the features of GO pathogenesis involving target autoantigens and their signaling pathways.
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Affiliation(s)
- Mohd Shazli Draman
- Thyroid Research Group, Cardiff University School of Medicine, Cardiff, United Kingdom
- KPJ Healthcare University College, Nilai, Malaysia
| | - Lei Zhang
- Thyroid Research Group, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Colin Dayan
- Thyroid Research Group, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Marian Ludgate
- Thyroid Research Group, Cardiff University School of Medicine, Cardiff, United Kingdom
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Heidari Z, Jami M. Parvovirus B19 Infection Is Associated with Autoimmune Thyroid Disease in Adults. Int J Endocrinol Metab 2021; 19:e115592. [PMID: 35069751 PMCID: PMC8762377 DOI: 10.5812/ijem.115592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 08/28/2021] [Accepted: 08/29/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Autoimmune thyroid diseases are the most frequent autoimmune disorders, with a global prevalence of about 10%. Several mechanisms have been proposed to induce autoimmune thyroid responses by infectious agents. In this study, we aimed to evaluate the association between parvovirus B19 infection and autoimmune thyroid disorders. METHODS Adult patients with newly diagnosed Graves' disease (GD) and Hashimoto's thyroiditis (HT) and healthy euthyroid controls were recruited. Various clinical and biochemical parameters, including thyroid function tests and serum parvovirus B19 antibody level (IgG), were assessed and compared between the groups. RESULTS In this study, data from 404 cases with HT, 248 cases with GD, and 480 healthy individuals as a control group were analyzed. The prevalence of parvovirus B19 infection in patients with HT and GD and controls was 61.1%, 58.9%, and 47.1%, respectively. In the group of patients with HT, there was a significant positive correlation between the B19 IgG and TPOAb (r = 0.764, P < 0.001) and TgAb (r = 0.533, P < 0.001). Also, in patients with GD, the B19 IgG had a significant positive correlation with TPOAb (r = 0.779, P < 0.001) and TgAb (r = 0.467, P < 0.001). CONCLUSIONS Parvovirus B19 infection is commonly seen in patients with autoimmune thyroid disorders.
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Affiliation(s)
- Zahra Heidari
- Department of Endocrinology and Metabolism, Zahedan University of Medical Sciences, Zahedan, Iran
- Corresponding Author: Department of Endocrinology and Metabolism, Zahedan University of Medical Sciences, Zahedan, Iran.
| | - Maede Jami
- Department of Endocrinology and Metabolism, Zahedan University of Medical Sciences, Zahedan, Iran
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Kalinkovich A, Livshits G. Biased and allosteric modulation of bone cell-expressing G protein-coupled receptors as a novel approach to osteoporosis therapy. Pharmacol Res 2021; 171:105794. [PMID: 34329703 DOI: 10.1016/j.phrs.2021.105794] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/20/2021] [Accepted: 07/25/2021] [Indexed: 12/16/2022]
Abstract
On the cellular level, osteoporosis (OP) is a result of imbalanced bone remodeling, in which osteoclastic bone resorption outcompetes osteoblastic bone formation. Currently available OP medications include both antiresorptive and bone-forming drugs. However, their long-term use in OP patients, mainly in postmenopausal women, is accompanied by severe side effects. Notably, the fundamental coupling between bone resorption and formation processes underlies the existence of an undesirable secondary outcome that bone anabolic or anti-resorptive drugs also reduce bone formation. This drawback requires the development of anti-OP drugs capable of selectively stimulating osteoblastogenesis and concomitantly reducing osteoclastogenesis. We propose that the application of small synthetic biased and allosteric modulators of bone cell receptors, which belong to the G-protein coupled receptors (GPCR) family, could be the key to resolving the undesired anti-OP drug selectivity. This approach is based on the capacity of these GPCR modulators, unlike the natural ligands, to trigger signaling pathways that promote beneficial effects on bone remodeling while blocking potentially deleterious effects. Under the settings of OP, an optimal anti-OP drug should provide fine-tuned regulation of downstream effects, for example, intermittent cyclic AMP (cAMP) elevation, preservation of Ca2+ balance, stimulation of osteoprotegerin (OPG) and estrogen production, suppression of sclerostin secretion, and/or preserved/enhanced canonical β-catenin/Wnt signaling pathway. As such, selective modulation of GPCRs involved in bone remodeling presents a promising approach in OP treatment. This review focuses on the evidence for the validity of our hypothesis.
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Affiliation(s)
- Alexander Kalinkovich
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6905126, Israel
| | - Gregory Livshits
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6905126, Israel; Adelson School of Medicine, Ariel University, Ariel 4077625, Israel.
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Mezei M, Latif R, Das B, Davies TF. Implications of an Improved Model of the TSH Receptor Transmembrane Domain (TSHR-TMD-TRIO). Endocrinology 2021; 162:6161546. [PMID: 33693584 PMCID: PMC8183494 DOI: 10.1210/endocr/bqab051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Indexed: 11/19/2022]
Abstract
The thyroid-stimulating hormone receptor (TSHR) is a G-protein-coupled receptor group A family member with 7 transmembrane helices. We generated 3 new models of its entire transmembrane region using a 600 ns molecular simulation. The simulation started from our previously published model, which we have now revised by also modeling the intracellular loops and the C-terminal tail, adding internal waters and embedding it into a lipid bilayer with a water layer and with ions added to complete the system. We have named this model TSHR-TMD-TRIO since 3 representative dominant structures were then extracted from the simulation trajectory and compared with the original model. These structures each showed small but significant changes in the relative positions of the helices. The 3 models were also used as targets to dock a set of small molecules that are known active compounds including a new TSHR antagonist (BT362), which confirmed the appropriateness of the model with some small molecules showing significant preference for one or other of the structures.
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Affiliation(s)
- Mihaly Mezei
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Correspondence: Mihaly Mezei, PhD, Icahn School of Medicine at Mount Sinai, New York, NY, USA. E-mail:
| | - Rauf Latif
- Thyroid Research Unit, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- James J. Peters VA Medical Center, New York, NY, USA
| | - Bhaskar Das
- Arnold & Marie Schwartz College of Pharmacy & Health Sciences, Long Island University, New York, NY, USA
| | - Terry F Davies
- Thyroid Research Unit, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- James J. Peters VA Medical Center, New York, NY, USA
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Ding Y, Yang S, Gao H. Teprotumumab: The Dawn of Therapies in Moderate-to-Severe Thyroid-Associated Ophthalmopathy. Horm Metab Res 2021; 53:211-218. [PMID: 33853117 DOI: 10.1055/a-1386-4512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Thyroid-associated ophthalmopathy (TAO) is a potentially sight-threatening ocular disease. About 3-5% of patients with TAO have severe disease with intense pain, inflammation, and sight-threatening corneal ulceration or compressive optic neuropathy. The current treatments of TAO are often suboptimal, mainly because the existing therapies do not target the pathogenesis of the disease. TAO mechanism is unclear. Ocular fibrocytes express relatively high levels of the functional TSH receptor (TSHR), and many indirect evidences support its participation. Over expression of insulin-like growth factor-1 receptor (IGF-IR) in fibroblasts, leading to inappropriate expression of inflammatory factors, production of hyaluronic acid and cell activation in orbital fibroblasts are also possible mechanisms. IGF-1R and TSHR form a physical and functional signaling complex. Inhibition of IGF-IR activity leads to the attenuation of signaling initiated at either receptor. Teprotumumab (TMB) is a human immunoglobulin G1 monoclonal antibody, binding to IGF-IR. Recently two TMB clinical trials had been implemented in TAO patients, indicating dramatic reductions in disease activity and severity, which approved its use for the treatment of TAO in the US. This review summarizes the treatments of TAO, focusing on the pathogenesis of IGF-1R in TAO and its application prospects.
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Affiliation(s)
- Yizhi Ding
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Shaoqin Yang
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Hua Gao
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
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Abstract
The insulin-like growth factor (IGF) pathway comprises two activating ligands (IGF-I and IGF-II), two cell-surface receptors (IGF-IR and IGF-IIR), six IGF binding proteins (IGFBP) and nine IGFBP related proteins. IGF-I and the IGF-IR share substantial structural and functional similarities to those of insulin and its receptor. IGF-I plays important regulatory roles in the development, growth, and function of many human tissues. Its pathway intersects with those mediating the actions of many cytokines, growth factors and hormones. Among these, IGFs impact the thyroid and the hormones that it generates. Further, thyroid hormones and thyrotropin (TSH) can influence the biological effects of growth hormone and IGF-I on target tissues. The consequences of this two-way interplay can be far-reaching on many metabolic and immunologic processes. Specifically, IGF-I supports normal function, volume and hormone synthesis of the thyroid gland. Some of these effects are mediated through enhancement of sensitivity to the actions of TSH while others may be independent of pituitary function. IGF-I also participates in pathological conditions of the thyroid, including benign enlargement and tumorigenesis, such as those occurring in acromegaly. With regard to Graves' disease (GD) and the periocular process frequently associated with it, namely thyroid-associated ophthalmopathy (TAO), IGF-IR has been found overexpressed in orbital connective tissues, T and B cells in GD and TAO. Autoantibodies of the IgG class are generated in patients with GD that bind to IGF-IR and initiate the signaling from the TSHR/IGF-IR physical and functional protein complex. Further, inhibition of IGF-IR with monoclonal antibody inhibitors can attenuate signaling from either TSHR or IGF-IR. Based on those findings, the development of teprotumumab, a β-arrestin biased agonist as a therapeutic has resulted in the first medication approved by the US FDA for the treatment of TAO. Teprotumumab is now in wide clinical use in North America.
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The Clinical Value and Variation of Antithyroid Antibodies during Pregnancy. DISEASE MARKERS 2020; 2020:8871951. [PMID: 33144894 PMCID: PMC7599418 DOI: 10.1155/2020/8871951] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 07/15/2020] [Accepted: 07/31/2020] [Indexed: 01/03/2023]
Abstract
Antithyroid antibodies, which include thyroid-stimulating hormone receptor antibodies (TRAbs), thyroid peroxidase antibodies (TPOAbs), and thyroid globulin antibodies (TgAbs), are widely known for their tight association with thyroid autoimmune diseases. The variation in all three kinds of antibodies also showed different trends during and after pregnancy (Weetman, 2010). This article reviewed the the physiological changes, while focusing on the variation of thyroid antibodies concentration in women during and after pregnancy, and adverse consequences related to their elevation. Since abnormal elevations of these antithyroid antibodies may lead to adverse outcomes in both mothers and fetuses, special attention must be paid to the titer of the antibodies during pregnancy. The molecular mechanisms of the variations in those antibodies have yet to be explained. The frequency and timing of thyroid antibody measurement, as well as different reference levels, also remain to be elucidated.
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12
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Ma L, Zhen J, Sorisky A. Regulators of thymic stromal lymphopoietin production by human adipocytes. Cytokine 2020; 136:155284. [PMID: 32950025 DOI: 10.1016/j.cyto.2020.155284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 01/07/2023]
Abstract
Thymic stromal lymphopoietin (TSLP) is a cytokine that is known to play a role in inflammatory conditions, especially asthma and atopic dermatitis. It is also recognized to be expressed in human adipose tissue. TSLP production from human adipocytes is stimulated by thyroid-stimulating hormone (TSH). This study aimed to identify TSH-dependent signaling routes that regulate TSLP, to determine if TSLP production is stimulated by other cytokines (IL-1β and TNF-α), and to examine if TSLP production depends on the adipose depot. Human abdominal differentiated adipocytes were stimulated with TSH, IL-1β, or TNF-α. Activation of cell signaling kinases was measured by phospho-immunoblot analysis, and TSLP in medium was assessed by ELISA. TSLP responses from abdominal subcutaneous and omental adipocytes were compared. TSH-stimulated TSLP secretion from subcutaneous adipocytes was enhanced by IBMX (raises cAMP levels) and was blocked by UO126 (inhibitor of MEK1/2-ERK1/2). TSLP secretion was stimulated by IL-1β and by TNF-α. SC-514 (inhibitor of IKKβ/NF-κB) only reduced the former. There was no effect of SB203580 (p38 MAPK inhibitor) or SP600125 (JNK inhibitor) on the stimulation by TSH, IL-1β or TNF-α. Interferon-γ inhibited TSLP responses to TSH, IL-1β, and TNF-α; IL-4 only blocked the response to TNFα. Intra-abdominal omental adipocytes also release TSLP in response to TSH, IL-1β, and TNF-α. We conclude TSLP is produced by human differentiated adipocytes derived from subcutaneous or omental depots in response to a variety of agonists. Further studies will be needed to understand what role it may play in adipose biology.
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Affiliation(s)
- Loretta Ma
- Chronic Disease Program, Ottawa Hospital Research Institute, 501 Smyth Rd, Ottawa, Ontario K1H 8L6, Canada
| | - Jamie Zhen
- Chronic Disease Program, Ottawa Hospital Research Institute, 501 Smyth Rd, Ottawa, Ontario K1H 8L6, Canada
| | - Alexander Sorisky
- Chronic Disease Program, Ottawa Hospital Research Institute, 501 Smyth Rd, Ottawa, Ontario K1H 8L6, Canada; Department of Medicine and Biochemistry, Microbiology & Immunology, University of Ottawa, 501 Smyth Rd, Ottawa, Ontario K1H 8L6, Canada.
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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: 167] [Impact Index Per Article: 41.8] [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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14
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Can neutrophil/lymphocyte ratio be used as an indicator of inflammation in patients with hyperthyroidism? J Med Biochem 2020; 39:7-12. [PMID: 32549771 DOI: 10.2478/jomb-2019-0004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/23/2019] [Indexed: 01/02/2023] Open
Abstract
Background In our study, we aimed to evaluate changes in the neutrophil and lymphocyte series and investigate whether the neutrophil/lymphocyte ratio (NLR) is indicative of inflammations in patients with hyperthyroidism. Methods A total of 161 patients were enrolled, 121 of which had hyperthyroidism (71 Graves' Disease (GD) and 50 non-Graves hyperthyroidism (NGH) patients) and 40 of which were control group members. Retrospectively, patients' neutrophil and lymphocyte counts were taken, and the NLR was calculated. Results While the number of neutrophils was significantly lower in the GD group (p = 0.003), there was no significant difference between the NGH and the control group. In the GD group, NLR values were significantly lower than the other two groups (median 1.39 for GD, median 1.84 for NGH and median 1.83 for the control group, p < 0.001). Only three patients in the GD group had neutropenia. There was also a significant negative correlation between free T3 and neutrophil count and NLR in hyperthyroid patients (r = -0.28, p = 0.001 and r = -0.34, p < 0.001, respectively). Conclusions In our study, we found that NLR did not in crease in hyperthyroid patients and that this ratio decreased due to the decrease in neutrophil levels in GD. We thus concluded that NLR is not a suitable indicator of hyperthyroidism.
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Boutin A, Gershengorn MC, Neumann S. β-Arrestin 1 in Thyrotropin Receptor Signaling in Bone: Studies in Osteoblast-Like Cells. Front Endocrinol (Lausanne) 2020; 11:312. [PMID: 32508750 PMCID: PMC7251030 DOI: 10.3389/fendo.2020.00312] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/24/2020] [Indexed: 12/20/2022] Open
Abstract
A direct action of thyrotropin (TSH, thyroid-stimulating hormone) on bone precursors in humans is controversial. Studies in rodent models have provided conflicting findings. We used cells derived from a moderately differentiated osteosarcoma stably overexpressing human TSH receptors (TSHRs) as a model of osteoblast precursors (U2OS-TSHR cells) to investigate TSHR-mediated effects in bone differentiation in human cells. We review our findings that (1) TSHR couples to several different G proteins to induce upregulation of genes associated with osteoblast activity-interleukin 11 (IL-11), osteopontin (OPN), and alkaline phosphatase (ALPL) and that the kinetics of the induction and the G protein-mediated signaling pathways involved were different for these genes; (2) TSH can stimulate β-arrestin-mediated signal transduction and that β-arrestin 1 in part mediates TSH-induced pre-osteoblast differentiation; and (3) TSHR/insulin-like growth factor 1 (IGF1) receptor (IGF1R) synergistically increased OPN secretion by TSH and IGF1 and that this crosstalk was mediated by physical association of these receptors in a signaling complex that uses β-arrestin 1 as a scaffold. These findings were complemented using a novel β-arrestin 1-biased agonist of TSHR. We conclude that TSHR can signal via several transduction pathways leading to differentiation of this model system of human pre-osteoblast cells and, therefore, that TSH can directly regulate these bone cells.
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16
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Akuka A, Watad A, Comaneshter D, Cohen AD, Amital H, Bragazzi NL. Systemic sclerosis patients are at higher risk of hyperthyroidism and have a worse survival than those without hyperthyroidism: A nationwide population-based cohort study. Eur J Clin Invest 2019; 49:e13177. [PMID: 31633804 DOI: 10.1111/eci.13177] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 08/18/2019] [Accepted: 10/10/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND A high prevalence of thyroid disorders has been reported in patients with autoimmune diseases. The link between hyperthyroidism and systemic sclerosis (SSc) has been relatively overlooked, and only a few studies utilizing small samples or case reports have been reported so far. OBJECTIVES To investigate the association between SSc and hyperthyroidism. METHODS We designed a case-control study utilizing the medical database of the Clalit Health Services. Chi-square and t tests were used for univariate analysis, and a logistic regression model was used for multivariate analysis. RESULTS The study included 2,431 SSc patients and 12,710 age- and sex-matched controls. The mean age of the study population was 63.32 ± 18.06 years (median 66 years), and female-to-male ratio was 4.5:1. Age (P < .0001, OR 1.03 [95% CI 1.02-1.04]), female sex (P = .0015, OR 1.86 [95% CI 1.27- 2.74]) and diagnosis of SSc (P = .0011, OR 1.81[95% CI 1.27-2.58]) were all independently associated with hyperthyroidism. Patients with SSc and hyperthyroidism had 1.54-fold increase of mortality rates during a mean follow-up of 17 years than SSc patients without hyperthyroidism, even though at the Cox multivariate survival analysis, only age (HR 1.06 [95% CI 1.06-1.07], P < .0001) and diagnosis of SSc (HR 2.35 [CI 2.06 to 2.69], P < .0001) resulted associated with a higher risk of mortality. CONCLUSIONS Hyperthyroidism is highly prevalent among SSc patients and can negatively impact on their survival rates. Therefore, a pre-emptive screening may be warranted in all SSc patients. Further studies are needed to evaluate whether tight control and optimal treatment for hyperthyroidism may lead to a reduction of all-cause mortality in patients with SSc.
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Affiliation(s)
- Aviram Akuka
- Department of Medicine 'B', Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Abdulla Watad
- Department of Medicine 'B', Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.,Leeds Institute of Rheumatic and Musculoskeletal Medicine (LIRMM), University of Leeds, Leeds, UK
| | - Doron Comaneshter
- Chief Physician's Office, Clalit Health Services Tel Aviv, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Arnon D Cohen
- Chief Physician's Office, Clalit Health Services Tel Aviv, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel.,Siaal Research Center for Family Medicine and Primary Care, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Howard Amital
- Department of Medicine 'B', Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Nicola L Bragazzi
- Department of Health Sciences (DISSAL), School of Public Health, University of Genoa, Genoa, Italy.,Laboratory for Industrial and Applied Mathematics (LIAM), Department of Mathematics and Statistics, York University, Toronto, ON, Canada
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17
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Cui Y, Rijhsinghani A. Role of Maternal Thyroid-Stimulating Immunoglobulin in Graves' Disease for Predicting Perinatal Thyroid Dysfunction. AJP Rep 2019; 9:e341-e345. [PMID: 31723454 PMCID: PMC6847696 DOI: 10.1055/s-0039-1694035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 05/06/2019] [Indexed: 01/18/2023] Open
Abstract
Objective To assess maternal thyroid-stimulating immunoglobulin (TSI) as a predictor of neonatal thyroid hyperthyroidism in pregnancies complicated by Graves' disease. Methods This is a 10-year retrospective study of patients with a history of Graves' disease and elevated TSI activity level defined as 1.3 times the normal. All subjects underwent cordocentesis for ultrasound findings of suspected fetal thyrotoxicosis (fetal tachycardia, oligohydramnios, hydrops, and thyromegaly). Neonatal diagnosis was made based on neonatal thyroid function testing or symptoms. Results Fourteen patients were included in the study, seven with active Graves' disease requiring antithyroid drug ("ATD group") and seven with iatrogenic hypothyroidism on levothyroxine ("levothyroxine group"). Four cases (57%) of neonatal thyrotoxicosis were diagnosed in the levothyroxine group compared with two cases (28%) in the ATD group. The lowest maternal TSI level at which a neonate did not develop hyperthyroidism was 2.6 for the levothyroxine group and 2.5 for the ATD group. The odds ratio of a neonate from the levothyroxine group developing hyperthyroidism compared with one from the ATD group is 3.3 (95% confidence interval: 0.4-30.7). Conclusion For patients with Graves' disease, those with iatrogenic hypothyroidism and TSI > 2.5 times the basal level are at the highest risk for neonatal thyrotoxicosis.
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Affiliation(s)
- Yiwen Cui
- Department of Obstetrics and Gynecology, Albany Medical Center, Albany, New York
| | - Asha Rijhsinghani
- Department of Obstetrics and Gynecology, Albany Medical Center, Albany, New York.,Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Fetal Diagnosis Unit, University of Iowa, Iowa City, Iowa
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18
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Zhou Z, Zuo CL, Li XS, Ye XP, Zhang QY, Wang P, Zhang RX, Chen G, Yang JL, Chen Y, Ma QY, Song HD. Uterus globulin associated protein 1 (UGRP1) is a potential marker of progression of Graves' disease into hypothyroidism. Mol Cell Endocrinol 2019; 494:110492. [PMID: 31255731 DOI: 10.1016/j.mce.2019.110492] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/21/2019] [Accepted: 06/24/2019] [Indexed: 01/26/2023]
Abstract
Approximately 20% of Graves' disease (GD) patients may result eventually in hypothyroidism in their natural course. Uterus globulin-associated protein 1 (UGRP1) was associated with GD in our previous study. Here we investigated the role of UGRP1 in the development of autoimmune thyroid disease (AITD). The results showed that UGRP1 was expressed in the thyrocytes of most Hashimoto's thyroiditis (HT) patients and a proportion of GD patients (293 HT and 198 GD). The pathologic features of UGRP1-positive thyrocytes resembled "Hürthle cells", and were surrounded by infiltrated leukocytes. The positivity rate of TPOAb in UGRP1-positive GD patients was much higher than that in -negative GD patients. Moreover, UGRP1 was co-expressed with Fas and HLA-DR in the thyrocytes of AITD patients. We also found IL-1β but not Th1 or Th2 cytokines was able to upregulate the expression of UGRP1. Our findings indicated that UGRP1 may be a novel marker in thyrocytes to predict GD patients who develop hypothyroidism.
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Affiliation(s)
- Zheng Zhou
- The Core Laboratory in Medical Center of Clinical Research, Department of Endocrinology, Shanghai Ninth People's Hospital, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Chun-Lin Zuo
- Department of Endocrinology, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, China.
| | - Xue-Song Li
- Department of Endocrinology, Minhang Hospital, Fudan University, Shanghai, China.
| | - Xiao-Ping Ye
- The Core Laboratory in Medical Center of Clinical Research, Department of Endocrinology, Shanghai Ninth People's Hospital, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Qian-Yue Zhang
- The Core Laboratory in Medical Center of Clinical Research, Department of Endocrinology, Shanghai Ninth People's Hospital, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Ping Wang
- Department of Pathology, Basic Medical College, Zhejiang Chinese Medical University, Zhejiang, China.
| | - Rong-Xin Zhang
- Department of Thoracic Surgery, The First Hospital Affiliated to University of Science and Technology of China, Anhui, China.
| | - Gang Chen
- Department of Endocrinology, Fujian Province Hospital, Fujian, China.
| | - Jia-Lin Yang
- Department of Endocrinology, Minhang Hospital, Fudan University, Shanghai, China.
| | - Yue Chen
- Department of Endocrinology, Shanghai Baoshan Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai, China.
| | - Qin-Yun Ma
- Department of Endocrinology and Metabolism, Shanghai Institute of Endocrine and Metabolic Diseases, China National Research Center for Metabolic Diseases, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
| | - Huai-Dong Song
- The Core Laboratory in Medical Center of Clinical Research, Department of Endocrinology, Shanghai Ninth People's Hospital, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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19
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Davies TF, Latif R. Editorial: TSH Receptor and Autoimmunity. Front Endocrinol (Lausanne) 2019; 10:19. [PMID: 30761086 PMCID: PMC6364331 DOI: 10.3389/fendo.2019.00019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 01/14/2019] [Indexed: 01/01/2023] Open
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20
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Kraus CN, Sodha P, Vaidyanathan P, Kirkorian AY. Thyroid dermopathy and acropachy in pediatric patients. Pediatr Dermatol 2018; 35:e371-e374. [PMID: 30187962 DOI: 10.1111/pde.13670] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The extrathyroid manifestations of Graves disease (GD) include thyroid orbitopathy, dermopathy, and acropachy. Thyroid dermopathy (TD), also known as pretibial myxedema, classically presents as nonpitting edema or plaquelike lesions on the pretibial region, while thyroid acropachy (TA) is seen in cases of severe TD, characterized by soft tissue swelling and clubbing of fingers and toes, as well as a periosteal reaction of the bones of the hands and feet. Both TD and TA are rare manifestations of thyroid disease and uncommonly reported in pediatric patients. Our aim was to increase awareness of dermatological manifestations associated with pediatric GD and review the literature of pediatric thyroid dermopathy as well as report a case of acropachy in a child.
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Affiliation(s)
- Christina N Kraus
- Department of Dermatology, University of California, Irvine, California
| | - Pooja Sodha
- Department of Dermatology, Duke University, Durham, North Carolina
| | - Priya Vaidyanathan
- Division of Endocrinology, Children's National Health System, Washington, District of Columbia.,George Washington University School of Medicine & Health Sciences, Washington, District of Columbia
| | - A Yasmine Kirkorian
- George Washington University School of Medicine & Health Sciences, Washington, District of Columbia.,Division of Dermatology, Children's National Health System, Washington, District of Columbia
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21
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Mazziotti G, Frara S, Giustina A. Pituitary Diseases and Bone. Endocr Rev 2018; 39:440-488. [PMID: 29684108 DOI: 10.1210/er.2018-00005] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 04/16/2018] [Indexed: 12/12/2022]
Abstract
Neuroendocrinology of bone is a new area of research based on the evidence that pituitary hormones may directly modulate bone remodeling and metabolism. Skeletal fragility associated with high risk of fractures is a common complication of several pituitary diseases such as hypopituitarism, Cushing disease, acromegaly, and hyperprolactinemia. As in other forms of secondary osteoporosis, pituitary diseases generally affect bone quality more than bone quantity, and fractures may occur even in the presence of normal or low-normal bone mineral density as measured by dual-energy X-ray absorptiometry, making difficult the prediction of fractures in these clinical settings. Treatment of pituitary hormone excess and deficiency generally improves skeletal health, although some patients remain at high risk of fractures, and treatment with bone-active drugs may become mandatory. The aim of this review is to discuss the physiological, pathophysiological, and clinical insights of bone involvement in pituitary diseases.
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Affiliation(s)
| | - Stefano Frara
- Institute of Endocrinology, Università Vita-Salute San Raffaele, Milan, Italy
| | - Andrea Giustina
- Institute of Endocrinology, Università Vita-Salute San Raffaele, Milan, Italy
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22
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Mohyi M, Smith TJ. IGF1 receptor and thyroid-associated ophthalmopathy. J Mol Endocrinol 2018; 61:T29-T43. [PMID: 29273685 PMCID: PMC6561656 DOI: 10.1530/jme-17-0276] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 12/22/2017] [Indexed: 12/13/2022]
Abstract
Thyroid-associated ophthalmopathy (TAO) is a vexing and poorly understood autoimmune process involving the upper face and tissues surrounding the eyes. In TAO, the orbit can become inflamed and undergo substantial remodeling that is disfiguring and can lead to loss of vision. There are currently no approved medical therapies for TAO, the consequence of its uncertain pathogenic nature. It usually presents as a component of the syndrome known as Graves' disease where loss of immune tolerance to the thyrotropin receptor (TSHR) results in the generation of activating antibodies against that protein and hyperthyroidism. The role for TSHR and these antibodies in the development of TAO is considerably less well established. We have reported over the past 2 decades evidence that the insulin-like growth factorI receptor (IGF1R) may also participate in the pathogenesis of TAO. Activating antibodies against IGF1R have been detected in patients with GD. The actions of these antibodies initiate signaling in orbital fibroblasts from patients with the disease. Further, we have identified a functional and physical interaction between TSHR and IGF1R. Importantly, it appears that signaling initiated from either receptor can be attenuated by inhibiting the activity of IGF1R. These findings underpin the rationale for therapeutically targeting IGF1R in active TAO. A recently completed therapeutic trial of teprotumumab, a human IGF1R inhibiting antibody, in patients with moderate to severe, active TAO, indicates the potential effectiveness and safety of the drug. It is possible that other autoimmune diseases might also benefit from this treatment strategy.
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Affiliation(s)
- Michelle Mohyi
- Department of Ophthalmology and Visual SciencesUniversity of Michigan, Ann Arbor, Michigan, USA
| | - Terry J Smith
- Department of Ophthalmology and Visual SciencesUniversity of Michigan, Ann Arbor, Michigan, USA
- Division of MetabolismEndocrine, and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
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23
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Rydzewska M, Jaromin M, Pasierowska IE, Stożek K, Bossowski A. Role of the T and B lymphocytes in pathogenesis of autoimmune thyroid diseases. Thyroid Res 2018; 11:2. [PMID: 29449887 PMCID: PMC5812228 DOI: 10.1186/s13044-018-0046-9] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 01/30/2018] [Indexed: 12/29/2022] Open
Abstract
Autoimmune thyroid disorders (AITD) broadly include Graves' disease and Hashimoto's thyroiditis which are the most common causes of thyroid gland dysfunctions. These disorders develop due to complex interactions between environmental and genetic factors and are characterized by reactivity to self-thyroid antigens due to autoreactive lymphocytes escaping tolerance. Both cell-mediated and humoral responses lead to tissue injury in autoimmune thyroid disease. The differentiation of CD4+ cells in the specific setting of immune mediators (for example cytokines, chemokines) results in differentiation of various T cell subsets. T cell identification has shown a mixed pattern of cytokine production indicating that both subtypes of T helper, Th1 and Th2, responses are involved in all types of AITD. Furthermore, recent studies described T cell subtypes Th17 and Treg which also play an essential role in pathogenesis of AITD. This review will focus on the role of the T regulatory (Treg) and T helper (Th) (especially Th17) lymphocytes, and also of B lymphocytes in AITD pathogenesis. However, we have much more to learn about cellular mechanisms and interactions in AITD before we can develop complete understanding of AITD pathophysiology.
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Affiliation(s)
- Marta Rydzewska
- Department of Pediatrics, Endocrinology and Diabetes with a Cardiology Unit, Medical University of Bialystok, ul. Waszyngtona 17, 15-274 Białystok, Poland
| | - Michał Jaromin
- Department of Pediatrics, Endocrinology and Diabetes with a Cardiology Unit, Medical University of Bialystok, ul. Waszyngtona 17, 15-274 Białystok, Poland
| | - Izabela Elżbieta Pasierowska
- Department of Pediatrics, Endocrinology and Diabetes with a Cardiology Unit, Medical University of Bialystok, ul. Waszyngtona 17, 15-274 Białystok, Poland
| | - Karlina Stożek
- Department of Pediatrics, Endocrinology and Diabetes with a Cardiology Unit, Medical University of Bialystok, ul. Waszyngtona 17, 15-274 Białystok, Poland
| | - Artur Bossowski
- Department of Pediatrics, Endocrinology and Diabetes with a Cardiology Unit, Medical University of Bialystok, ul. Waszyngtona 17, 15-274 Białystok, Poland
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24
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Neumann S, Eliseeva E, Boutin A, Barnaeva E, Ferrer M, Southall N, Kim D, Hu X, Morgan SJ, Marugan JJ, Gershengorn MC. Discovery of a Positive Allosteric Modulator of the Thyrotropin Receptor: Potentiation of Thyrotropin-Mediated Preosteoblast Differentiation In Vitro. J Pharmacol Exp Ther 2017; 364:38-45. [PMID: 29089368 DOI: 10.1124/jpet.117.244095] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/26/2017] [Indexed: 01/01/2023] Open
Abstract
Recently, we showed that TSH-enhanced differentiation of a human preosteoblast-like cell model involved a β-arrestin 1 (β-Arr 1)-mediated pathway. To study this pathway in more detail, we sought to discover a small molecule ligand that was functionally selective toward human TSH receptor (TSHR) activation of β-Arr 1. High-throughput screening using a cell line stably expressing mutated TSHRs and mutated β-Arr 1 (DiscoverX1 cells) led to the discovery of agonists that stimulated translocation of β-Arr 1 to the TSHR, but did not activate Gs-mediated signaling pathways, i.e., cAMP production. D3-βArr (NCGC00379308) was selected. In DiscoverX1 cells, D3-βArr stimulated β-Arr 1 translocation with a 5.1-fold greater efficacy than TSH and therefore potentiated the effect of TSH in stimulating β-Arr 1 translocation. In human U2OS-TSHR cells expressing wild-type TSHRs, which is a model of human preosteoblast-like cells, TSH upregulated the osteoblast-specific genes osteopontin (OPN) and alkaline phosphatase (ALPL). D3-βArr alone had only a weak effect to upregulate these bone markers, but D3-βArr potentiated TSH-induced upregulation of ALPL and OPN mRNA levels 1.6-fold and 5.5-fold, respectively, at the maximum dose of ligands. Furthermore, the positive allosteric modulator effect of D3-βArr resulted in an increase of TSH-induced secretion of OPN protein. In summary, we have discovered the first small molecule positive allosteric modulator of TSHR. As D3-βArr potentiates the effect of TSH to enhance differentiation of a human preosteoblast in an in vitro model, it will allow a novel experimental approach for probing the role of TSH-induced β-Arr 1 signaling in osteoblast differentiation.
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Affiliation(s)
- Susanne Neumann
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Elena Eliseeva
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Alisa Boutin
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Elena Barnaeva
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Marc Ferrer
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Noel Southall
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - David Kim
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Xin Hu
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Sarah J Morgan
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Juan J Marugan
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
| | - Marvin C Gershengorn
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (S.N., E.E., A.B., S.J.M., M.C.G.); and Division of Pre-Clinical Innovations, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland (E.B., M.F., N.S., D.K., X.H., J.J.M.)
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Baliram R, Latif R, Zaidi M, Davies TF. Expanding the Role of Thyroid-Stimulating Hormone in Skeletal Physiology. Front Endocrinol (Lausanne) 2017; 8:252. [PMID: 29042858 PMCID: PMC5632520 DOI: 10.3389/fendo.2017.00252] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/13/2017] [Indexed: 12/11/2022] Open
Abstract
The dogma that thyroid-stimulating hormone (TSH) solely regulates the production of thyroid hormone from the thyroid gland has hampered research on its wider physiological roles. The action of pituitary TSH on the skeleton has now been well described; in particular, its action on osteoblasts and osteoclasts. It has also been recently discovered that the bone marrow microenvironment acts as an endocrine circuit with bone marrow-resident macrophages capable of producing a novel TSH-β subunit variant (TSH-βv), which may modulate skeletal physiology. Interestingly, the production of this TSH-βv is positively regulated by T3 accentuating such modulation in the presence of thyroid overactivity. Furthermore, a number of small molecule ligands acting as TSH agonists, which allosterically modulate the TSH receptor have been identified and may have similar modulatory influences on bone cells suggesting therapeutic potential. This review summarizes our current understanding of the role of TSH, TSH-β, TSH-βv, and small molecule agonists in bone physiology.
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Affiliation(s)
- Ramkumarie Baliram
- Thyroid Research Unit, Icahn School of Medicine at Mount Sinai and the James J. Peters VA Medical Center, New York, NY, United States
- *Correspondence: Ramkumarie Baliram,
| | - Rauf Latif
- Thyroid Research Unit, Icahn School of Medicine at Mount Sinai and the James J. Peters VA Medical Center, New York, NY, United States
| | - Mone Zaidi
- The Mount Sinai Bone Program, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Terry F. Davies
- Thyroid Research Unit, Icahn School of Medicine at Mount Sinai and the James J. Peters VA Medical Center, New York, NY, United States
- The Mount Sinai Bone Program, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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Kleinau G, Worth CL, Kreuchwig A, Biebermann H, Marcinkowski P, Scheerer P, Krause G. Structural-Functional Features of the Thyrotropin Receptor: A Class A G-Protein-Coupled Receptor at Work. Front Endocrinol (Lausanne) 2017; 8:86. [PMID: 28484426 PMCID: PMC5401882 DOI: 10.3389/fendo.2017.00086] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/03/2017] [Indexed: 12/21/2022] Open
Abstract
The thyroid-stimulating hormone receptor (TSHR) is a member of the glycoprotein hormone receptors, a sub-group of class A G-protein-coupled receptors (GPCRs). TSHR and its endogenous ligand thyrotropin (TSH) are of essential importance for growth and function of the thyroid gland and proper function of the TSH/TSHR system is pivotal for production and release of thyroid hormones. This receptor is also important with respect to pathophysiology, such as autoimmune (including ophthalmopathy) or non-autoimmune thyroid dysfunctions and cancer development. Pharmacological interventions directly targeting the TSHR should provide benefits to disease treatment compared to currently available therapies of dysfunctions associated with the TSHR or the thyroid gland. Upon TSHR activation, the molecular events conveying conformational changes from the extra- to the intracellular side of the cell across the membrane comprise reception, conversion, and amplification of the signal. These steps are highly dependent on structural features of this receptor and its intermolecular interaction partners, e.g., TSH, antibodies, small molecules, G-proteins, or arrestin. For better understanding of signal transduction, pathogenic mechanisms such as autoantibody action and mutational modifications or for developing new pharmacological strategies, it is essential to combine available structural data with functional information to generate homology models of the entire receptor. Although so far these insights are fragmental, in the past few decades essential contributions have been made to investigate in-depth the involved determinants, such as by structure determination via X-ray crystallography. This review summarizes available knowledge (as of December 2016) concerning the TSHR protein structure, associated functional aspects, and based on these insights we suggest several receptor complex models. Moreover, distinct TSHR properties will be highlighted in comparison to other class A GPCRs to understand the molecular activation mechanisms of this receptor comprehensively. Finally, limitations of current knowledge and lack of information are discussed highlighting the need for intensified efforts toward TSHR structure elucidation.
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Affiliation(s)
- Gunnar Kleinau
- Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin, Berlin, Germany
- Group Protein X-Ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin, Berlin, Germany
| | | | - Annika Kreuchwig
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin, Berlin, Germany
| | | | - Patrick Scheerer
- Group Protein X-Ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin, Berlin, Germany
| | - Gerd Krause
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Berlin, Germany
- *Correspondence: Gerd Krause,
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Kleinau G, Kalveram L, Köhrle J, Szkudlinski M, Schomburg L, Biebermann H, Grüters-Kieslich A. Minireview: Insights Into the Structural and Molecular Consequences of the TSH-β Mutation C105Vfs114X. Mol Endocrinol 2016; 30:954-64. [PMID: 27387040 DOI: 10.1210/me.2016-1065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Naturally occurring thyrotropin (TSH) mutations are rare, which is also the case for the homologous heterodimeric glycoprotein hormones (GPHs) follitropin (FSH), lutropin (LH), and choriogonadotropin (CG). Patients with TSH-inactivating mutations present with central congenital hypothyroidism. Here, we summarize insights into the most frequent loss-of-function β-subunit of TSH mutation C105Vfs114X, which is associated with isolated TSH deficiency. This review will address the following question. What is currently known on the molecular background of this TSH variant on a protein level? It has not yet been clarified how C105Vfs114X causes early symptoms in affected patients, which are comparably severe to those observed in newborns lacking any functional thyroid tissue (athyreosis). To better understand the mechanisms of this mutant, we have summarized published reports and complemented this information with a structural perspective on GPHs. By including the ancestral TSH receptor agonist thyrostimulin and pathogenic mutations reported for FSH, LH, and choriogonadotropin in the analysis, insightful structure function and evolutionary restrictions become apparent. However, comparisons of immunogenicity and bioactivity of different GPH variants is hindered by a lack of consensus for functional analysis and the diversity of used GPH assays. Accordingly, relevant gaps of knowledge concerning details of GPH mutation-related effects are identified and highlighted in this review. These issues are of general importance as several previous and recent studies point towards the high impact of GPH variants in differential signaling regulation at GPH receptors (GPHRs), both endogenously and under diseased conditions. Further improvement in this area is of decisive importance for the development of novel targeted therapies.
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Affiliation(s)
- Gunnar Kleinau
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Laura Kalveram
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Josef Köhrle
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Mariusz Szkudlinski
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Lutz Schomburg
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
| | - Annette Grüters-Kieslich
- Institute of Experimental Pediatric Endocrinology (G.K., L.K., H.B.), Charité-Universitätsmedizin, Berlin, 13353 Germany; Institute of Experimental Endocrinology (J.K., L.S.), Charité-Universitätsmedizin Berlin, 13353 Germany; Trophogen, Inc (M.S.), Rockville, Maryland 20850; and Department of Pediatric Endocrinology and Diabetes (A.G.-K.), Charité-Universitätsmedizin, Berlin, 13353 Germany
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Boutin A, Neumann S, Gershengorn MC. Multiple Transduction Pathways Mediate Thyrotropin Receptor Signaling in Preosteoblast-Like Cells. Endocrinology 2016; 157:2173-81. [PMID: 26950201 PMCID: PMC4870888 DOI: 10.1210/en.2015-2040] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/01/2016] [Indexed: 12/20/2022]
Abstract
It has been shown that the TSH receptor (TSHR) couples to a number of different signaling pathways, although the Gs-cAMP pathway has been considered primary. Here, we measured the effects of TSH on bone marker mRNA and protein expression in preosteoblast-like U2OS cells stably expressing TSHRs. We determined which signaling cascades are involved in the regulation of IL-11, osteopontin (OPN), and alkaline phosphatase (ALPL). We demonstrated that TSH-induced up-regulation of IL-11 is primarily mediated via the Gs pathway as IL-11 was up-regulated by forskolin (FSK), an adenylyl cyclase activator, and inhibited by protein kinase A inhibitor H-89 and by silencing of Gαs by small interfering RNA. OPN levels were not affected by FSK, but its up-regulation was inhibited by TSHR/Gi-uncoupling by pertussis toxin. Pertussis toxin decreased p38 MAPK kinase phosphorylation, and a p38 inhibitor and small interfering RNA knockdown of p38α inhibited OPN induction by TSH. Up-regulation of ALPL expression required high doses of TSH (EC50 = 395nM), whereas low doses (EC50 = 19nM) were inhibitory. FSK-stimulated cAMP production decreased basal ALPL expression, whereas protein kinase A inhibition by H-89 and silencing of Gαs increased basal levels of ALPL. Knockdown of Gαq/11 and a protein kinase C inhibitor decreased TSH-stimulated up-regulation of ALPL, whereas a protein kinase C activator increased ALPL levels. A MAPK inhibitor and silencing of ERK1/2 inhibited TSH-stimulated ALPL expression. We conclude that TSH regulates expression of different bone markers via distinct signaling pathways.
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Affiliation(s)
- Alisa Boutin
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Susanne Neumann
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Marvin C Gershengorn
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Rapoport B, McLachlan SM. TSH Receptor Cleavage Into Subunits and Shedding of the A-Subunit; A Molecular and Clinical Perspective. Endocr Rev 2016; 37:114-34. [PMID: 26799472 PMCID: PMC4823380 DOI: 10.1210/er.2015-1098] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 01/14/2016] [Indexed: 02/07/2023]
Abstract
The TSH receptor (TSHR) on the surface of thyrocytes is unique among the glycoprotein hormone receptors in comprising two subunits: an extracellular A-subunit, and a largely transmembrane and cytosolic B-subunit. Unlike its ligand TSH, whose subunits are encoded by two genes, the TSHR is expressed as a single polypeptide that subsequently undergoes intramolecular cleavage into disulfide-linked subunits. Cleavage is associated with removal of a C-peptide region, a mechanism similar in some respects to insulin cleavage into disulfide linked A- and B-subunits with loss of a C-peptide region. The potential pathophysiological importance of TSHR cleavage into A- and B-subunits is that some A-subunits are shed from the cell surface. Considerable experimental evidence supports the concept that A-subunit shedding in genetically susceptible individuals is a factor contributing to the induction and/or affinity maturation of pathogenic thyroid-stimulating autoantibodies, the direct cause of Graves' disease. The noncleaving gonadotropin receptors are not associated with autoantibodies that induce a "Graves' disease of the gonads." We also review herein current information on the location of the cleavage sites, the enzyme(s) responsible for cleavage, the mechanism by which A-subunits are shed, and the effects of cleavage on receptor signaling.
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Affiliation(s)
- Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048
| | - Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048
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Rapoport B, McLachlan SM. Withdrawn: TSH Receptor Cleavage Into Subunits and Shedding of the A-Subunit; A Molecular and Clinical Perspective. Endocr Rev 2016; 2016:23-42. [PMID: 27454362 PMCID: PMC6958993 DOI: 10.1210/er.2015-1098.2016.1.test] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 01/14/2016] [Indexed: 12/29/2022]
Abstract
The TSH receptor (TSHR) on the surface of thyrocytes is unique among the glycoprotein hormone receptors in comprising two subunits: an extracellular A-subunit, and a largely transmembrane and cytosolic B-subunit. Unlike its ligand TSH, whose subunits are encoded by two genes, the TSHR is expressed as a single polypeptide that subsequently undergoes intramolecular cleavage into disulfide-linked subunits. Cleavage is associated with removal of a C-peptide region, a mechanism similar in some respects to insulin cleavage into disulfide linked A- and B-subunits with lossofaC-peptideregion. The potential pathophysiological importance of TSHR cleavage into A-and B-subunits is that some A-subunits are shed from the cell surface. Considerable experimental evidence supports the concept that A-subunit shedding in genetically susceptible individuals is a factor contributing to the induction and/or affinity maturation of pathogenic thyroid-stimulating autoantibodies, the direct cause of Graves' disease. The noncleaving gonadotropin receptors are not associated with autoantibodies that induce a "Graves' disease of the gonads." We also review herein current information on the location of the cleavage sites, the enzyme(s) responsible for cleavage, the mechanism by which A-subunits are shed, and the effects of cleavage on receptor signaling. (Endocrine Reviews 37: 114-134, 2016).
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Affiliation(s)
- Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048
| | - Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048
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Latif R, Lau Z, Cheung P, Felsenfeld DP, Davies TF. The "TSH Receptor Glo Assay" - A High-Throughput Detection System for Thyroid Stimulation. Front Endocrinol (Lausanne) 2016; 7:3. [PMID: 26858688 PMCID: PMC4729884 DOI: 10.3389/fendo.2016.00003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 01/12/2016] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND To identify novel small molecules against the TSH receptor, we developed a sensitive transcription-based luciferase high-throughput screening (HTS) system named the TSHR-Glo Assay (TSHR-Glo). METHODS This assay uses double-transfected Chinese hamster ovary cells stably expressing the human TSHR and a cAMP-response element (CRE) construct fused to an improved luciferase reporter gene. RESULTS The assay was highly responsive toward TSH in a dose-dependent manner with a TSH sensitivity of 10(-10)M (10 ± 1.12 μU/ml) and thyroid-stimulating antibodies, a hallmark of Graves' disease, could also be detected. The assay was validated against the standard indicator of HTS performance - the Z-factor (Z') - producing a score of 0.895. Using the TSHR-Glo assay, we screened 48,224 compounds from a diverse chemical library in duplicate plates at a fixed dose of 17 μM. Twenty molecules with the greatest activity out of 62 molecules that were identified by this technique were subsequently screened against the parent luciferase stable cell line in order to eliminate false positive stimulators. CONCLUSION Using this approach, we were able to identify specific agonists against the TSH receptor leading to the characterization of several TSH agonist molecules. Hence, the TSHR-Glo assay was a one-step cell-based HTS assay, which was successful in the discovery of novel small molecular agonists and for the detection of stimulating antibodies to the TSH receptor.
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Affiliation(s)
- Rauf Latif
- Thyroid Research Unit, Department of Medicine, Icahn School of Medicine at Mount Sinai and the James J. Peters VA Medical Center, New York, NY, USA
- *Correspondence: Rauf Latif,
| | - Zerlina Lau
- Integrated Screening Core, Experimental Therapeutics Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pamela Cheung
- Integrated Screening Core, Experimental Therapeutics Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Dan P. Felsenfeld
- Integrated Screening Core, Experimental Therapeutics Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Terry F. Davies
- Thyroid Research Unit, Department of Medicine, Icahn School of Medicine at Mount Sinai and the James J. Peters VA Medical Center, New York, NY, USA
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Abstract
The TSH receptor (TSHR) has the propensity to form dimers and oligomers. Our data using ectodomain-truncated TSHRs indicated that the predominant interfaces for oligomerization reside in the transmembrane (TM) domain. To map the potentially interacting residues, we first performed in silico studies of the TSHR transmembrane domain using a homology model and using Brownian dynamics (BD). The cluster of dimer conformations obtained from BD analysis indicated that TM1 made contact with TM4 and two residues in TM2 made contact with TM5. To confirm the proximity of these contact residues, we then generated cysteine mutants at all six contact residues predicted by the BD analysis and performed cysteine cross-linking studies. These results showed that the predicted helices in the protomer were indeed involved in proximity interactions. Furthermore, an alternative experimental approach, receptor truncation experiments and LH receptor sequence substitution experiments, identified TM1 harboring a major region involved in TSHR oligomerization, in agreement with the conclusion from the cross-linking studies. Point mutations of the predicted interacting residues did not yield a substantial decrease in oligomerization, unlike the truncation of the TM1, so we concluded that constitutive oligomerization must involve interfaces forming domains of attraction in a cooperative manner that is not dominated by interactions between specific residues.
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Affiliation(s)
- Rauf Latif
- Thyroid Research Unit (R.L., M.R.A., T.F.D.) and Departments of Medicine (R.L., M.R.A., T.F.D.) and Structural and Chemical Biology (M.M.), Icahn School of Medicine at Mt Sinai School of Medicine, New York, New York 10029; and James J. Peters Veterans Affairs Medical Center (R.L., M.R.A., T.F.D.), New York, New York 10468
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Ali MR, Latif R, Davies TF, Mezei M. Monte Carlo loop refinement and virtual screening of the thyroid-stimulating hormone receptor transmembrane domain. J Biomol Struct Dyn 2014; 33:1140-52. [PMID: 25012978 DOI: 10.1080/07391102.2014.932310] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Metropolis Monte Carlo (MMC) loop refinement has been performed on the three extracellular loops (ECLs) of rhodopsin and opsin-based homology models of the thyroid-stimulating hormone receptor transmembrane domain, a class A type G protein-coupled receptor. The Monte Carlo sampling technique, employing torsion angles of amino acid side chains and local moves for the six consecutive backbone torsion angles, has previously reproduced the conformation of several loops with known crystal structures with accuracy consistently less than 2 Å. A grid-based potential map, which includes van der Waals, electrostatics, hydrophobic as well as hydrogen-bond potentials for bulk protein environment and the solvation effect, has been used to significantly reduce the computational cost of energy evaluation. A modified sigmoidal distance-dependent dielectric function has been implemented in conjunction with the desolvation and hydrogen-bonding terms. A long high-temperature simulation with 2 kcal/mol repulsion potential resulted in extensive sampling of the conformational space. The slow annealing leading to the low-energy structures predicted secondary structure by the MMC technique. Molecular docking with the reported agonist reproduced the binding site within 1.5 Å. Virtual screening performed on the three lowest structures showed that the ligand-binding mode in the inter-helical region is dependent on the ECL conformations.
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Affiliation(s)
- M Rejwan Ali
- a Thyroid Research Unit , Icahn School of Medicine at Mount Sinai , New York , NY , USA
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van der Weerd K, van Hagen PM, Schrijver B, Heuvelmans SJWM, Hofland LJ, Swagemakers SMA, Bogers AJJC, Dik WA, Visser TJ, van Dongen JJM, van der Lelij AJ, Staal FJT. Thyrotropin acts as a T-cell developmental factor in mice and humans. Thyroid 2014; 24:1051-61. [PMID: 24635198 DOI: 10.1089/thy.2013.0396] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Using gene expression profiling, we detected differential thyrotropin receptor (TSH-R) expression during human T-cell development in the thymus. This expression pattern indicated a potential role for the TSH-R within the thymus, independent of its function in the thyroid gland. Here, we demonstrate that TSH-R expression is thymus-specific within the immune system. TSH was able to bind and activate the TSH-R present on thymocytes, thereby activating calcium signaling and cyclic adenosine monophosphate signaling pathways. Mice lacking functional TSH-R expression (hyt/hyt mice) were shown to have lower frequencies of DP and SP thymocytes compared to their heterozygous littermates. Moreover, addition of TSH to co-cultures of human thymocytes enhanced T-cell development. Thus, TSH acts as a previously unrecognized growth factor for developing T cells, with potential clinical use to enhance thymic output and thereby the functional T-cell repertoire in the periphery. The direct effects of TSH on thymocytes may also explain the thus far enigmatic thymic hyperplasia in Graves' disease.
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Affiliation(s)
- Kim van der Weerd
- 1 Department of Immunology, Erasmus University Medical Center , Rotterdam, The Netherlands
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Gagnon A, Langille ML, Chaker S, Antunes TT, Durand J, Sorisky A. TSH signaling pathways that regulate MCP-1 in human differentiated adipocytes. Metabolism 2014; 63:812-21. [PMID: 24661543 DOI: 10.1016/j.metabol.2014.02.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 02/25/2014] [Accepted: 02/25/2014] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Adipose tissue is an extra-thyroidal thyroid-stimulating hormone (TSH) target. Increases in lipolysis and in expression and release of interleukin-6 (IL-6) occur in TSH-stimulated adipocytes, and levels of circulating free fatty acids and IL-6 rise following TSH administration to patients with previous thyroidectomy and radioablation for thyroid cancer. Our first objective was to compare how TSH stimulates protein kinase A (PKA) and inhibitor of κB (IκB) kinase (IKK)-β. Our second objective was to investigate whether TSH induces other cytokines besides IL-6. METHODS TSH stimulation of either CHO cells expressing human TSH receptor or human abdominal subcutaneous differentiated adipocytes. RESULTS Signaling studies showed TSH increased NADPH oxidase activity, and either diphenyleneiodonium (oxidase inhibitor) or N-acetyl cysteine (scavenger of reactive oxygen species) reduced IKKβ phosphorylation. Phosphorylation of protein kinase C-δ, an upstream regulator of NADPH oxidase, was increased by TSH, and rottlerin (PKCδ inhibitor) reduced TSH-stimulated IKKβ phosphorylation. TSH upregulated monocyte chemoattractant protein-1 (MCP-1) mRNA expression and the release of MCP-1 protein in human abdominal differentiated adipocytes. H89 (PKA inhibitor) and sc-514 (IKKβ inhibitor) each blocked TSH-stimulated MCP-1 mRNA expression and protein release, suggesting PKA and IKKβ participate in this pathway. CONCLUSIONS These data provide new information about TSH signaling in human differentiated adipocytes, and add to the evidence that TSH is a pro-inflammatory stimulus of adipocytes.
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Affiliation(s)
- AnneMarie Gagnon
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Melanie L Langille
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Seham Chaker
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Tayze T Antunes
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Jason Durand
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Alexander Sorisky
- Chronic Disease Program, Ottawa Hospital Research Institute, Departments of Medicine and of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Ontario, Canada.
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Gagnon A, Mahzari M, Lochnan HA, Sorisky A. Acute TSH stimulation in vivo does not alter serum PCSK9 levels. Thyroid Res 2014; 7:4. [PMID: 24808925 PMCID: PMC4012524 DOI: 10.1186/1756-6614-7-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/24/2014] [Indexed: 12/02/2022] Open
Abstract
Background It is now recognized that TSH can act on targets other than the thyroid, including the liver. Elevated serum TSH levels in euthyroid subjects were recently reported to correlate with high values of serum proprotein convertase subtilisin/kexin type 9 (PCSK9). This protein, expressed and secreted by hepatocytes, promotes higher LDL-cholesterol levels. We tested whether an acute increase of TSH levels following administration of TSH in vivo would raise PCSK9 levels in patients who had previously undergone total thyroidectomy and radioablation for thyroid cancer. Findings TSH levels rose from 0.64 ± 1.02 mU/L on day 1 to 98.66 ± 4.83 mU/L on day 3, following injections of recombinant human TSH (on days 1 and 2). PCSK9 levels were 330 ± 99 ng/ml on day 1, and did not change on days 3 or 5 in response to TSH stimulation. Conclusions Although a positive correlation between TSH and PCSK9 in euthyroid subjects has raised the possibility that TSH might act on the liver to raise PCSK9 values, our data show that PCSK9 levels are not affected by acute elevations of TSH levels. Whether chronic elevations of TSH are needed to upregulate PCSK9 remains to be determined.
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Affiliation(s)
- Annemarie Gagnon
- Chronic Disease Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Canada ; Department of Medicine, University of Ottawa, Ottawa, Canada ; Department Biochemistry, Microbiology &Immunology, University of Ottawa, Ottawa, Canada
| | - Moeber Mahzari
- Chronic Disease Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Canada ; Department of Medicine, University of Ottawa, Ottawa, Canada
| | - Heather A Lochnan
- Chronic Disease Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Canada ; Department of Medicine, University of Ottawa, Ottawa, Canada
| | - Alexander Sorisky
- Chronic Disease Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Canada ; Department of Medicine, University of Ottawa, Ottawa, Canada ; Department Biochemistry, Microbiology &Immunology, University of Ottawa, Ottawa, Canada ; Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
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Boutin A, Eliseeva E, Gershengorn MC, Neumann S. β-Arrestin-1 mediates thyrotropin-enhanced osteoblast differentiation. FASEB J 2014; 28:3446-55. [PMID: 24723693 DOI: 10.1096/fj.14-251124] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Thyrotropin (TSH) activation of the TSH receptor (TSHR), a 7-transmembrane-spanning receptor (7TMR), may have osteoprotective properties by direct effects on bone. TSHR activation by TSH phosphorylates protein kinases AKT1, p38α, and ERK1/2 in some cells. We found TSH-induced phosphorylation of these kinases in 2 cell lines engineered to express TSHRs, human embryonic kidney HEK-TSHR cells and human osteoblastic U2OS-TSHR cells. In U2OS-TSHR cells, TSH up-regulated pAKT1 (7.1±0.5-fold), p38α (2.9±0.4-fold), and pERK1/2 (3.1±0.2-fold), whereas small molecule TSHR agonist C2 had no or little effect on pAKT1 (1.8±0.08-fold), p38α (1.2±0.09-fold), and pERK1/2 (1.6±0.19-fold). Furthermore, TSH increased expression of osteoblast marker genes ALPL (8.2±4.6-fold), RANKL (21±5.9-fold), and osteopontin (OPN; 17±5.3-fold), whereas C2 had little effect (ALPL, 1.7±0.5-fold; RANKL, 1.3±0.6-fold; and OPN, 2.2±0.7-fold). β-Arrestin-1 and -2 can mediate activatory signals by 7TMRs. TSH stimulated translocation of β-arrestin-1 and -2 to TSHR, whereas C2 failed to translocate either β-arrestin. Down-regulation of β-arrestin-1 by siRNA inhibited TSH-stimulated phosphorylation of ERK1/2, p38α, and AKT1, whereas down-regulation of β-arrestin-2 increased phosphorylation of AKT1 in both cell types and of ERK1/2 in HEK-TSHR cells. Knockdown of β-arrestin-1 inhibited TSH-stimulated up-regulation of mRNAs for OPN by 87 ± 1.7% and RANKL by 73 ± 2.4%, and OPN secretion by 74 ± 10%. We conclude that TSH enhances osteoblast differentiation in U2OS cells that is, in part, caused by activatory signals mediated by β-arrestin-1.
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Affiliation(s)
- Alisa Boutin
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Elena Eliseeva
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Marvin C Gershengorn
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Susanne Neumann
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Jiang X, Dias JA, He X. Structural biology of glycoprotein hormones and their receptors: insights to signaling. Mol Cell Endocrinol 2014; 382:424-451. [PMID: 24001578 DOI: 10.1016/j.mce.2013.08.021] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 08/20/2013] [Accepted: 08/24/2013] [Indexed: 01/18/2023]
Abstract
This article reviews the progress made in the field of glycoprotein hormones (GPH) and their receptors (GPHR) by several groups of structural biologists including ourselves aiming to gain insight into GPH signaling mechanisms. The GPH family consists of four members, with follicle-stimulating hormone (FSH) being the prototypic member. GPH members belong to the cystine-knot growth factor superfamily, and their receptors (GPHR), possessing unusually large N-terminal ectodomains, belong to the G-protein coupled receptor Family A. GPHR ectodomains can be divided into two subdomains: a high-affinity hormone binding subdomain primarily centered on the N-terminus, and a second subdomain that is located on the C-terminal region of the ectodomain that is involved in signal specificity. The two subdomains unexpectedly form an integral structure comprised of leucine-rich repeats (LRRs). Following the structure determination of hCG in 1994, the field of FSH structural biology has progressively advanced. Initially, the FSH structure was determined in partially glycosylated free form in 2001, followed by a structure of FSH bound to a truncated FSHR ectodomain in 2005, and the structure of FSH bound to the entire ectodomain in 2012. Comparisons of the structures in three forms led a proposal of a two-step monomeric receptor activation mechanism. First, binding of FSH to the FSHR high-affinity hormone-binding subdomain induces a conformational change in the hormone to form a binding pocket that is specific for a sulfated-tyrosine found as sTyr 335 in FSHR. Subsequently, the sTyr is drawn into the newly formed binding pocket, producing a lever effect on a helical pivot whereby the docking sTyr provides as the 'pull & lift' force. The pivot helix is flanked by rigid LRRs and locked by two disulfide bonds on both sides: the hormone-binding subdomain on one side and the last short loop before the first transmembrane helix on the other side. The lift of the sTyr loop frees the tethered extracellular loops of the 7TM domain, thereby releasing a putative inhibitory influence of the ectodomain, ultimately leading to the activating conformation of the 7TM domain. Moreover, the data lead us to propose that FSHR exists as a trimer and to present an FSHR activation mechanism consistent with the observed trimeric crystal form. A trimeric receptor provides resolution of the enigmatic, but important, biological roles played by GPH residues that are removed from the primary FSH-binding site, as well as several important GPCR phenomena, including negative cooperativity and asymmetric activation. Further reflection pursuant to this review process revealed additional novel structural characteristics such as the identification of a 'seat' sequence in GPH. Together with the 'seatbelt', the 'seat' enables a common heteodimeric mode of association of the common α subunit non-covalently and non-specifically with each of the three different β subunits. Moreover, it was possible to establish a dimensional order that can be used to estimate LRR curvatures. A potential binding pocket for small molecular allosteric modulators in the FSHR 7TM domain has also been identified.
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Affiliation(s)
- Xuliang Jiang
- EMD Serono Research & Development Institute, Billerica, MA 01821, United States.
| | - James A Dias
- Department of Biomedical Sciences, School of Public Health, University at Albany-SUNY, Albany, NY 12222, United States
| | - Xiaolin He
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, United States
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Kleinau G, Biebermann H. Constitutive activities in the thyrotropin receptor: regulation and significance. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 70:81-119. [PMID: 24931193 DOI: 10.1016/b978-0-12-417197-8.00003-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The thyroid-stimulating hormone receptor (TSHR, or thyrotropin receptor) is a family A G protein-coupled receptor. It not only binds thyroid-stimulating hormone (TSH, or thyrotropin) but also interacts with autoantibodies under pathological conditions. The TSHR and TSH are essential for thyroid growth and function and thus for all thyroid hormone-associated physiological superordinated processes, including metabolism and development of the central nervous system. In vitro studies have found that the TSHR permanently stimulates ligand-independent (constitutive) activation of Gs, which ultimately leads to intracellular cAMP accumulation. Furthermore, a vast variety of constitutively activating mutations of TSHR-at more than 50 different amino acid positions-have been reported to enhance basal signaling. These lead in vivo to a "gain-of-function" phenotype of nonautoimmune hyperthyroidism or toxic adenomas. Moreover, many naturally occurring inactivating mutations are known to cause a "loss-of-function" phenotype, resulting in resistance to thyroid hormone or hyperthyrotropinemia. Several of these mutations are also characterized by impaired basal signaling, and these are designated here as "constitutively inactivating mutations" (CIMs). More than 30 amino acid positions with CIMs have been identified so far. Moreover, the permanent TSHR signaling capacity can also be blocked by inverse agonistic antibodies or small drug-like molecules, which both have a potential for clinical usage. In this chapter, information on constitutive activity in the TSHR is described, including up- and downregulation, linked protein conformations, physiological and pathophysiological conditions, and related intracellular signaling.
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Affiliation(s)
- Gunnar Kleinau
- Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Galofré JC, Chacón AM, Latif R. Targeting thyroid diseases with TSH receptor analogs. ACTA ACUST UNITED AC 2013; 60:590-8. [DOI: 10.1016/j.endonu.2012.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Accepted: 12/18/2012] [Indexed: 10/27/2022]
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Kleinau G, Neumann S, Grüters A, Krude H, Biebermann H. Novel insights on thyroid-stimulating hormone receptor signal transduction. Endocr Rev 2013; 34:691-724. [PMID: 23645907 PMCID: PMC3785642 DOI: 10.1210/er.2012-1072] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The TSH receptor (TSHR) is a member of the glycoprotein hormone receptors, a subfamily of family A G protein-coupled receptors. The TSHR is of great importance for the growth and function of the thyroid gland. The TSHR and its endogenous ligand TSH are pivotal proteins with respect to a variety of physiological functions and malfunctions. The molecular events of TSHR regulation can be summarized as a process of signal transduction, including signal reception, conversion, and amplification. The steps during signal transduction from the extra- to the intracellular sites of the cell are not yet comprehensively understood. However, essential new insights have been achieved in recent years on the interrelated mechanisms at the extracellular region, the transmembrane domain, and intracellular components. This review contains a critical summary of available knowledge of the molecular mechanisms of signal transduction at the TSHR, for example, the key amino acids involved in hormone binding or in the structural conformational changes that lead to G protein activation or signaling regulation. Aspects of TSHR oligomerization, signaling promiscuity, signaling selectivity, phenotypes of genetic variations, and potential extrathyroidal receptor activity are also considered, because these are relevant to an understanding of the overall function of the TSHR, including physiological, pathophysiological, and pharmacological perspectives. Directions for future research are discussed.
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Affiliation(s)
- Gunnar Kleinau
- Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, Ostring 3, Augustenburger Platz 1, 13353 Berlin, Germany.
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Szychta P, Szychta W, Gesing A, Lewiński A, Karbownik-Lewińska M. TSH receptor antibodies have predictive value for breast cancer - retrospective analysis. Thyroid Res 2013; 6:8. [PMID: 23680448 PMCID: PMC3662571 DOI: 10.1186/1756-6614-6-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/05/2013] [Indexed: 11/22/2022] Open
Abstract
Background Associations between breast cancer and thyroid disorders are reported in numerous studies. Relationships between thyroperoxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb) and breast cancer have been previously demonstrated. However, no analysis has been performed concerning an association between thyrotropin (TSH) receptor antibodies (TSHRAb) and breast cancer. The aim of the study was to evaluate the prevalence of breast cancer or benign breast tumors in patients with Graves’ disease and to analyze a possible relationship between Graves’ disease and these two groups of breast diseases with emphasis to epidemiology and laboratory findings. Patients and methods Clinical and laboratory details of 2003 women hospitalized for endocrine disorders were retrospectively analyzed, using an unpaired Student’s t-test, logistic regression analysis, χ2 test of independence or the two-sided ratio comparison test. Results The coexistence of Graves’ disease and breast cancer was statistically significant. We observed TSHRAb and TgAb more frequently in patients with breast cancer. We found that TSHRAb is the only variable possessing predictive value for breast cancer. Conclusions The strong relationship between Graves’ disease and breast cancer is proposed. We suggest that TSHRAb could be described as a positive determinant of breast cancer. The present data call attention to the usefulness of screening for breast cancer in long-term follow-up of patients with autoimmune thyroid disorders, especially of those with Graves’ disease. Similarly, screening for autoimmune thyroid disorders should be performed in patients with nodular breast disease. Additionally, the article draws ideas for further research in order to develop targeted treatment for more successful outcome in patients with breast cancer.
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Affiliation(s)
- Paweł Szychta
- Department of Oncological Endocrinology, Medical University of Lodz, 7/9 Zeligowski St,, 90-752, Lodz, Poland.
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Morshed SA, Latif R, Davies TF. Delineating the autoimmune mechanisms in Graves' disease. Immunol Res 2013; 54:191-203. [PMID: 22434518 DOI: 10.1007/s12026-012-8312-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The immunologic processes involved in autoimmune thyroid disease (AITD), particularly Graves' disease (GD), are similar to other autoimmune diseases with the emphasis on the antibodies as the most unique aspect. These characteristics include a lymphocytic infiltrate at the target organs, the presence of antigen-reactive T and B cells and antibodies, and the establishment of animal models of GD by antibody transfer or immunization with antigen. Similar to other autoimmune diseases, risk factors for GD include the presence of multiple susceptibility genes, including certain HLA alleles, and the TSHR gene itself. In addition, a variety of known risk factors and precipitators have been characterized including the influence of sex and sex hormones, pregnancy, stress, infection, iodine and other potential environmental factors. The pathogenesis of GD is likely the result of a breakdown in the tolerance mechanisms, both at central and peripheral levels. Different subsets of T and B cells together with their regulatory populations play important roles in the propagation and maintenance of the disease process. Understanding different mechanistic in the complex system biology interplay will help to identify unique factors contributing to the AITD pathogenesis.
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Affiliation(s)
- Syed A Morshed
- Thyroid Research Unit, Mount Sinai School of Medicine, James J. Peters VA Medical Center, 130 West Kingsbridge Rd, Bronx, New York, NY 10468, USA.
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Leschik JJ, Diana T, Olivo PD, König J, Krahn U, Li Y, Kanitz M, Kahaly GJ. Analytical performance and clinical utility of a bioassay for thyroid-stimulating immunoglobulins. Am J Clin Pathol 2013; 139:192-200. [PMID: 23355204 DOI: 10.1309/ajcpzut7cnueu7op] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
The analytical performance and the clinical utility of a thyrotropin receptor (TSHR)-stimulating immunoglobulin (TSI) bioassay were compared with those of a TSHR-binding inhibitory immunoglobulin (TBII) assay. Limits of detection (LoD) and quantitation (LoQ), assay cutoff, and the half-maximal effective concentration (EC(50)) were measured. Dilution analysis was performed in sera of hyperthyroid patients with Graves disease (GD) during antithyroid treatment (ATD). Titer was defined as the first dilution step at which measurement of TSI or TBII fell below the assay cutoff. The LoD, LoQ, cutoff, and EC(50) of the bioassay were 251-, 298-, 814-, and 827-fold lower than for the TBII assay. There were 22%, 42%, 23%, and 14% more positive samples in the TSI bioassay at dilutions of 1:3, 1:9, 1:27, and 1:81 (P < .0001), respectively. Responders to ATD demonstrated marked differences in titers compared with nonresponders. The bioassay detected lower levels of TSHR autoantibodies, and the dilution analysis provided similar predictive values of both assays in GD.
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Affiliation(s)
- Johannes J. Leschik
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
| | - Tanja Diana
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
| | | | - Jochem König
- Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), Division Medical Biometry, Johannes Gutenberg University Medical Center, Mainz, Germany
| | - Ulrike Krahn
- Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), Division Medical Biometry, Johannes Gutenberg University Medical Center, Mainz, Germany
| | - Yunsheng Li
- Diagnostic Hybrids, a Quidel Company, Athens, OH
| | - Michael Kanitz
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
| | - George J. Kahaly
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany
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van Steensel L, Hooijkaas H, Paridaens D, van den Bosch WA, Kuijpers RWAM, Drexhage HA, van Hagen PM, Dik WA. PDGF enhances orbital fibroblast responses to TSHR stimulating autoantibodies in Graves' ophthalmopathy patients. J Clin Endocrinol Metab 2012; 97:E944-53. [PMID: 22438231 DOI: 10.1210/jc.2012-1020] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE Thyroid-stimulating hormone receptor (TSHR) stimulating autoantibodies are associated with Graves' ophthalmopathy (GO), the orbital manifestation of Graves' disease (GD). TSHR autoantibody levels and orbital TSHR expression levels correlate positively with GO disease activity. Platelet-derived growth factors (PDGF) are increased in GO and potently activate orbital fibroblast effector functions. We investigated the possible relationship between PDGF and TSHR expression on orbital fibroblasts and how that influences the immunopathological effects of TSHR autoantibodies on orbital fibroblast activity. METHODS Orbital fibroblasts were stimulated with PDGF-AA, PDGF-AB, and PDGF-BB, and TSHR expression was determined by flow cytometry. Stimulatory effects of bovine TSH and GD immunoglobulins on orbital fibroblasts (with or without PDGF-BB preincubation) were determined by IL-6, IL-8, chemokine (C-C motif) ligand (CCL)-2, CCL5, CCL7, and hyaluronan ELISA. The TSHR blocking antibody K1-70 and the cAMP inhibitor H89 were used to determine involvement of TSHR signaling. RESULTS PDGF-AB and PDGF-BB stimulation increased TSHR expression on orbital fibroblasts, whereas PDGF-AA did not. Furthermore, stimulation with bovine TSH and immunoglobulins from GD patients induced IL-6, IL-8, CCL2, and hyaluronan production by orbital fibroblasts, and PDGF-BB preincubation enhanced this response of orbital fibroblasts. Blocking studies with a TSHR blocking antibody and a cAMP inhibitor inhibited these effects, indicating the involvement of TSHR signaling and thus of TSHR stimulating autoantibodies herein. CONCLUSIONS These findings indicate that PDGF-B containing PDGF isoforms amplify the immunopathological effects of TSHR-stimulating autoantibodies in GO patients by stimulating TSHR expression on orbital fibroblasts.
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Affiliation(s)
- L van Steensel
- Department of Immunology, Erasmus Medical Center, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands
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Abstract
INTRODUCTION The thyrotropin receptor (TSHR) is essential for thyroid growth and for the production of thyroid hormones. It is unique among the glycoprotein hormone receptors, in that some of the TSHRs undergo cleavage and shedding of the alpha subunit. AREAS COVERED This review discusses the structure and function of the TSHR, followed by an evaluation of its role in thyroid disease. Possible limitations of the TSHR as a therapeutic target are also discussed. EXPERT OPINION The TSHR is involved in a number of hereditary and acquired disorders of the thyroid making it of potential importance as a therapeutic target in thyroid disease. Expression of the TSHR in several non-thyroidal tissues and the development of systemic manifestations of thyroid disease suggest that the TSHR is also of interest as a therapeutic target outside the thyroid.
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Affiliation(s)
- Samer El-Kaissi
- Specialized Diabetes and Endocrine Centre, King Fahad Medical City, Dabab Street, P.O. Box 59046, Riyadh 11525, Saudi Arabia.
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Davies TF, Latif R, Minsky NC, Ma R. Clinical review: The emerging cell biology of thyroid stem cells. J Clin Endocrinol Metab 2011; 96:2692-702. [PMID: 21778219 PMCID: PMC3167664 DOI: 10.1210/jc.2011-1047] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Stem cells are undifferentiated cells with the property of self-renewal and give rise to highly specialized cells under appropriate local conditions. The use of stem cells in regenerative medicine holds great promise for the treatment of many diseases, including those of the thyroid gland. EVIDENCE ACQUISITION This review focuses on the progress that has been made in thyroid stem cell research including an overview of cellular and molecular events (most of which were drawn from the period 1990-2011) and discusses the remaining problems encountered in their differentiation. EVIDENCE SYNTHESIS Protocols for the in vitro differentiation of embryonic stem cells, based on normal developmental processes, have generated thyroid-like cells but without full thyrocyte function. However, agents have been identified, including activin A, insulin, and IGF-I, which are able to stimulate the generation of thyroid-like cells in vitro. In addition, thyroid stem/progenitor cells have been identified within the normal thyroid gland and within thyroid cancers. CONCLUSIONS Advances in thyroid stem cell biology are providing not only insight into thyroid development but may offer therapeutic potential in thyroid cancer and future thyroid cell replacement therapy.
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Affiliation(s)
- Terry F Davies
- Thyroid Research Unit, Mount Sinai School of Medicine, and the James J Peters Veterans Affairs Medical Center, New York, New York 10468, USA.
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Kleinau G, Mueller S, Jaeschke H, Grzesik P, Neumann S, Diehl A, Paschke R, Krause G. Defining structural and functional dimensions of the extracellular thyrotropin receptor region. J Biol Chem 2011; 286:22622-31. [PMID: 21525003 DOI: 10.1074/jbc.m110.211193] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The extracellular region of the thyrotropin receptor (TSHR) can be subdivided into the leucine-rich repeat domain (LRRD) and the hinge region. Both the LRRD and the hinge region interact with thyrotropin (TSH) or autoantibodies. Structural data for the TSHR LRRD were previously determined by crystallization (amino acids Glu(30)-Thr(257), 10 repeats), but the structure of the hinge region is still undefined. Of note, the amino acid sequence (Trp(258)-Tyr(279)) following the crystallized LRRD comprises a pattern typical for leucine-rich repeats with conserved hydrophobic side chains stabilizing the repeat fold. Moreover, functional data for amino acids between the LRRD and the transmembrane domain were fragmentary. We therefore investigated systematically these TSHR regions by mutagenesis to reveal insights into their functional contribution and potential structural features. We found that mutations of conserved hydrophobic residues between Thr(257) and Tyr(279) cause TSHR misfold, which supports a structural fold of this peptide, probably as an additional leucine-rich repeat. Furthermore, we identified several new mutations of hydrophilic amino acids in the entire hinge region leading to partial TSHR inactivation, indicating that these positions are important for intramolecular signal transduction. In summary, we provide new information regarding the structural features and functionalities of extracellular TSHR regions. Based on these insights and in context with previous results, we suggest an extracellular activation mechanism that supports an intramolecular agonistic unit as a central switch for activating effects at the extracellular region toward the serpentine domain.
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Affiliation(s)
- Gunnar Kleinau
- Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, D-13125 Berlin, Germany
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Neumann S, Eliseeva E, McCoy JG, Napolitano G, Giuliani C, Monaco F, Huang W, Gershengorn MC. A new small-molecule antagonist inhibits Graves' disease antibody activation of the TSH receptor. J Clin Endocrinol Metab 2011; 96:548-54. [PMID: 21123444 PMCID: PMC3048317 DOI: 10.1210/jc.2010-1935] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Graves' disease (GD) is caused by persistent, unregulated stimulation of thyrocytes by thyroid-stimulating antibodies (TSAbs) that activate the TSH receptor (TSHR). We previously reported the first small-molecule antagonist of human TSHR and showed that it inhibited receptor signaling stimulated by sera from four patients with GD. OBJECTIVE Our objective was to develop a better TSHR antagonist and use it to determine whether inhibition of TSAb activation of TSHR is a general phenomenon. DESIGN We aimed to chemically modify a previously reported small-molecule TSHR ligand to develop a better antagonist and determine whether it inhibits TSHR signaling by 30 GD sera. TSHR signaling was measured in two in vitro systems: model HEK-EM293 cells stably overexpressing human TSHRs and primary cultures of human thyrocytes. TSHR signaling was measured as cAMP production and by effects on thyroid peroxidase mRNA. RESULTS We tested analogs of a previously reported small-molecule TSHR inverse agonist and selected the best NCGC00229600 for further study. In the model system, NCGC00229600 inhibited basal and TSH-stimulated cAMP production. NCGC00229600 inhibition of TSH signaling was competitive even though it did not compete for TSH binding; that is, NCGC00229600 is an allosteric inverse agonist. NCGC00229600 inhibited cAMP production by 39 ± 2.6% by all 30 GD sera tested. In primary cultures of human thyrocytes, NCGC00229600 inhibited TSHR-mediated basal and GD sera up-regulation of thyroperoxidase mRNA levels by 65 ± 2.0%. CONCLUSION NCGC00229600, a small-molecule allosteric inverse agonist of TSHR, is a general antagonist of TSH receptor activation by TSAbs in GD patient sera.
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Affiliation(s)
- Susanne Neumann
- National Institute of Diabetes and Digestive and Kidney Diseases, Clinical Endocrinology Branch, National Institutes of Health, 50 South Drive, Bethesda, Maryland 20892-8029, USA.
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