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Lademann F, Tsourdi E, Hofbauer LC, Rauner M. Bone cell-specific deletion of thyroid hormone transporter Mct8 distinctly regulates bone volume in young versus adult male mice. Bone 2022; 159:116375. [PMID: 35240348 DOI: 10.1016/j.bone.2022.116375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 12/23/2022]
Abstract
Thyroid hormones are critical regulators of bone metabolism. Their cellular import is guided through transporter proteins, including the monocarboxylate transporter 8 (MCT8). Conditional Mct8 knockout in osteoblast and osteoclast precursors leads to trabecular bone gain in 12-week-old male mice. Given that thyroid hormones regulate both skeletal development and bone maintenance, we investigated the effect of bone cell-specific Mct8 deletion in 6-week-old (young) and 24-week-old (adult) male mice. Mct8 ablation in osteoclast precursors led to trabecular bone gain at the spine in 6-week-old animals compared to age-matched controls, whereas adult animals displayed a shift towards trabecular bone loss in both femur and vertebra. Mct8 deficiency in osteoprogenitors increased osteoblast numbers and trabecular bone mass at the spine of young mice, without skeletal differences between adult knockout mice and littermate controls. In contrast, young mice lacking Mct8 in late osteoblasts/osteocytes exhibited lower trabecular bone volume at the spine and femur compared to respective controls, but no differences were detected at 24 weeks of age. In vitro studies of osteoblasts with Dmp1-Cre promotor driven Mct8 deletion showed no significant alterations of osteogenic marker gene expression and mineralization capacity suggesting that MCT8 is not crucial for osteoblast maturation. Overall, we observed mild effects with conditional Mct8 knockout on bone microarchitecture and bone turnover especially during growth implying a secondary role for MCT8 as a thyroid hormone transporter in bone.
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Affiliation(s)
- Franziska Lademann
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, Germany
| | - Elena Tsourdi
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, Germany
| | - Lorenz C Hofbauer
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, Germany
| | - Martina Rauner
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, Germany.
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2
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Lademann F, Mayerl S, Tsourdi E, Verrey F, Leitch VD, Williams GR, Bassett JHD, Hofbauer LC, Heuer H, Rauner M. The Thyroid Hormone Transporter MCT10 Is a Novel Regulator of Trabecular Bone Mass and Bone Turnover in Male Mice. Endocrinology 2022; 163:bqab218. [PMID: 34669927 PMCID: PMC8598386 DOI: 10.1210/endocr/bqab218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Indexed: 11/19/2022]
Abstract
Thyroid hormones (TH) are essential for skeletal development and adult bone homeostasis. Their bioavailability is determined by specific transporter proteins at the cell surface. The TH-specific transporter monocarboxylate transporter 8 (MCT8) was recently reported as a regulator of bone mass in mice. Given that high systemic triiodothyronine (T3) levels in Mct8 knockout (KO) mice are still able to cause trabecular bone loss, alternative TH transporters must substitute for MCT8 function in bone. In this study, we analyzed the skeletal phenotypes of male Oatp1c1 KO and Mct10 KO mice, which are euthyroid, and male Mct8/Oatp1c1 and Mct8/Mct10 double KO mice, which have elevated circulating T3 levels, to unravel the role of TH transport in bone. MicroCT analysis showed no significant trabecular bone changes in Oatp1c1 KO mice at 4 weeks and 16 weeks of age compared with wild-type littermate controls, whereas 16-week-old Mct8/Oatp1c1 double KO animals displayed trabecular bone loss. At 12 weeks, Mct10 KO mice, but not Mct8/Mct10 double KO mice, had decreased trabecular femoral bone volume with reduced osteoblast numbers. By contrast, lack of Mct10 in 24-week-old mice led to trabecular bone gain at the femur with increased osteoblast numbers and decreased osteoclast numbers whereas Mct8/Mct10 double KO did not alter bone mass. Neither Mct10 nor Mct8/Mct10 deletion affected vertebral bone structures at both ages. In vitro, osteoblast differentiation and activity were impaired by Mct10 and Mct8/Mct10-deficiency. These data demonstrate that MCT10, but not OATP1C1, is a site- and age-dependent regulator of bone mass and turnover in male mice.
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Affiliation(s)
- Franziska Lademann
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, D-01307 Dresden, Germany
| | - Steffen Mayerl
- Department of Endocrinology, University of Duisburg-Essen, University Hospital Essen, D-45147 Essen, Germany
| | - Elena Tsourdi
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, D-01307 Dresden, Germany
| | - Francois Verrey
- Institute of Physiology, University of Zurich, CH-8057 Zurich, Switzerland
| | - Victoria D Leitch
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London SW7 2AZ, UK
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London SW7 2AZ, UK
| | - J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London SW7 2AZ, UK
| | - Lorenz C Hofbauer
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, D-01307 Dresden, Germany
| | - Heike Heuer
- Department of Endocrinology, University of Duisburg-Essen, University Hospital Essen, D-45147 Essen, Germany
| | - Martina Rauner
- Department of Medicine III and Center for Healthy Aging, Technische Universität Dresden, D-01307 Dresden, Germany
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3
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Zhu S, Pang Y, Xu J, Chen X, Zhang C, Wu B, Gao J. Endocrine Regulation on Bone by Thyroid. Front Endocrinol (Lausanne) 2022; 13:873820. [PMID: 35464058 PMCID: PMC9020229 DOI: 10.3389/fendo.2022.873820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND As an endocrine organ, the thyroid acts on the entire body by secreting a series of hormones, and bone is one of the main target organs of the thyroid. SUMMARY This review highlights the roles of thyroid hormones and thyroid diseases in bone homeostasis. CONCLUSION Thyroid hormones play significant roles in the growth and development of bone, and imbalance of thyroid hormones can impair bone homeostasis.
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Affiliation(s)
- Siyuan Zhu
- Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Yidan Pang
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Jun Xu
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Xiaoyi Chen
- Ningbo Institute of Life and Health Industry, University of Chinese Academy of Sciences, Ningbo, China
| | - Changqing Zhang
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- *Correspondence: Junjie Gao, ; Bo Wu, ; Changqing Zhang,
| | - Bo Wu
- Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- *Correspondence: Junjie Gao, ; Bo Wu, ; Changqing Zhang,
| | - Junjie Gao
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- Ningbo Institute of Life and Health Industry, University of Chinese Academy of Sciences, Ningbo, China
- *Correspondence: Junjie Gao, ; Bo Wu, ; Changqing Zhang,
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van Geest FS, Gunhanlar N, Groeneweg S, Visser WE. Monocarboxylate Transporter 8 Deficiency: From Pathophysiological Understanding to Therapy Development. Front Endocrinol (Lausanne) 2021; 12:723750. [PMID: 34539576 PMCID: PMC8440930 DOI: 10.3389/fendo.2021.723750] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/13/2021] [Indexed: 01/18/2023] Open
Abstract
Genetic defects in the thyroid hormone transporter monocarboxylate transporter 8 (MCT8) result in MCT8 deficiency. This disorder is characterized by a combination of severe intellectual and motor disability, caused by decreased cerebral thyroid hormone signalling, and a chronic thyrotoxic state in peripheral tissues, caused by exposure to elevated serum T3 concentrations. In particular, MCT8 plays a crucial role in the transport of thyroid hormone across the blood-brain-barrier. The life expectancy of patients with MCT8 deficiency is strongly impaired. Absence of head control and being underweight at a young age, which are considered proxies of the severity of the neurocognitive and peripheral phenotype, respectively, are associated with higher mortality rate. The thyroid hormone analogue triiodothyroacetic acid is able to effectively and safely ameliorate the peripheral thyrotoxicosis; its effect on the neurocognitive phenotype is currently under investigation. Other possible therapies are at a pre-clinical stage. This review provides an overview of the current understanding of the physiological role of MCT8 and the pathophysiology, key clinical characteristics and developing treatment options for MCT8 deficiency.
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Groeneweg S, van Geest FS, Peeters RP, Heuer H, Visser WE. Thyroid Hormone Transporters. Endocr Rev 2020; 41:5637505. [PMID: 31754699 DOI: 10.1210/endrev/bnz008] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
Abstract
Thyroid hormone transporters at the plasma membrane govern intracellular bioavailability of thyroid hormone. Monocarboxylate transporter (MCT) 8 and MCT10, organic anion transporting polypeptide (OATP) 1C1, and SLC17A4 are currently known as transporters displaying the highest specificity toward thyroid hormones. Structure-function studies using homology modeling and mutational screens have led to better understanding of the molecular basis of thyroid hormone transport. Mutations in MCT8 and in OATP1C1 have been associated with clinical disorders. Different animal models have provided insight into the functional role of thyroid hormone transporters, in particular MCT8. Different treatment strategies for MCT8 deficiency have been explored, of which thyroid hormone analogue therapy is currently applied in patients. Future studies may reveal the identity of as-yet-undiscovered thyroid hormone transporters. Complementary studies employing animal and human models will provide further insight into the role of transporters in health and disease. (Endocrine Reviews 41: 1 - 55, 2020).
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Affiliation(s)
- Stefan Groeneweg
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Ferdy S van Geest
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Robin P Peeters
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - W Edward Visser
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands Academic Center for Thyroid Diseases, Erasmus Medical Center, Rotterdam, the Netherlands
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Leitch VD, Bassett JHD, Williams GR. Role of thyroid hormones in craniofacial development. Nat Rev Endocrinol 2020; 16:147-164. [PMID: 31974498 DOI: 10.1038/s41574-019-0304-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/21/2019] [Indexed: 02/07/2023]
Abstract
The development of the craniofacial skeleton relies on complex temporospatial organization of diverse cell types by key signalling molecules. Even minor disruptions to these processes can result in deleterious consequences for the structure and function of the skull. Thyroid hormone deficiency causes delayed craniofacial and tooth development, dysplastic facial features and delayed development of the ossicles in the middle ear. Thyroid hormone excess, by contrast, accelerates development of the skull and, in severe cases, might lead to craniosynostosis with neurological sequelae and facial hypoplasia. The pathogenesis of these important abnormalities remains poorly understood and underinvestigated. The orchestration of craniofacial development and regulation of suture and synchondrosis growth is dependent on several critical signalling pathways. The underlying mechanisms by which these key pathways regulate craniofacial growth and maturation are largely unclear, but studies of single-gene disorders resulting in craniofacial malformations have identified a number of critical signalling molecules and receptors. The craniofacial consequences resulting from gain-of-function and loss-of-function mutations affecting insulin-like growth factor 1, fibroblast growth factor receptor and WNT signalling are similar to the effects of altered thyroid status and mutations affecting thyroid hormone action, suggesting that these critical pathways interact in the regulation of craniofacial development.
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Affiliation(s)
- Victoria D Leitch
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- Royal Melbourne Institute of Technology (RMIT) Centre for Additive Manufacturing, RMIT University, Melbourne, VIC, Australia
| | - J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
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7
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Lademann F, Tsourdi E, Rijntjes E, Köhrle J, Hofbauer LC, Heuer H, Rauner M. Lack of the Thyroid Hormone Transporter Mct8 in Osteoblast and Osteoclast Progenitors Increases Trabecular Bone in Male Mice. Thyroid 2020; 30:329-342. [PMID: 31910109 DOI: 10.1089/thy.2019.0271] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background: Bone is an important target of thyroid hormones (THs), which require transport into target cells to exert their actions. Recently, the TH-specific monocarboxylate transporter 8 (Mct8) was reported as a regulator of bone mass in male mice. However, its global deletion leads to high 3,3',5-L-triiodothyronine (T3) serum concentrations that may mask direct effects of Mct8-deficiency on bone. In this study, we assessed the bone cell intrinsic function of Mct8 ex vivo and in vivo using conditional Mct8-knockout lines specifically targeting osteoclast and osteoblast progenitors, as well as mature osteoblasts and osteocytes. Materials and Methods: Twelve-week-old male mice with a global Mct8-deficiency or a conditional Mct8-knockout in osteoclast precursors, osteoprogenitors, or mature osteoblasts/osteocytes were analyzed regarding their bone microarchitecture, turnover, and strength. Furthermore, ex vivo studies were conducted to investigate the role of Mct8 in bone cell differentiation and functionality, as well as TH uptake. Results: Global Mct8-knockout mice demonstrated 1.7-fold higher T3 serum concentrations and trabecular bone loss (-28%) likely due to an increased bone turnover as shown by increased osteoblast (+45%) and osteoclast numbers (+41%). However, cortical bone mineral density was increased. Ex vivo cultures of bone marrow-derived osteoblasts and osteoclasts revealed highest expression of Mct8 in mature bone cells. In addition, Mct8-deficiency resulted in a lower mRNA expression of osteoblast and osteoclast differentiation markers, as well as a reduced mineralization capacity and osteoclast numbers, respectively, indicating a bone cell intrinsic role of Mct8. In fact, conditional Mct8-knockout and inhibition of Mct8 in osteoblasts led to an attenuated T3 uptake ex vivo. In vivo, osteoprogenitor-specific Mct8-knockout enhanced trabecular bone volume (+16%) with osteoblast numbers being increased 3.7 fold. Interestingly, Mct8-deficiency in osteoprogenitors and late osteoblasts/osteocytes both resulted in cortical bone loss. Finally, Mct8-deletion in osteoclast progenitors increased trabecular bone volume (+20%) due to reduced osteoclast numbers (-32%), whereas osteoblast numbers were enhanced (+25%). Conclusions: This study confirms that high systemic T3 in global Mct8-knockout mice masks the direct effect of Mct8. Moreover, it identifies Mct8 as a critical regulator of trabecular vs. cortical bone by regulating T3 uptake and highlights its cell intrinsic role in osteoclast and osteoblast progenitors.
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Affiliation(s)
- Franziska Lademann
- Department of Medicine III, Universitätsklinikum Dresden, Dresden, Germany
- Center for Healthy Aging, Universitätsklinikum Dresden, Dresden, Germany
| | - Elena Tsourdi
- Department of Medicine III, Universitätsklinikum Dresden, Dresden, Germany
- Center for Healthy Aging, Universitätsklinikum Dresden, Dresden, Germany
| | - Eddy Rijntjes
- Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Josef Köhrle
- Institut für Experimentelle Endokrinologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Lorenz C Hofbauer
- Department of Medicine III, Universitätsklinikum Dresden, Dresden, Germany
- Center for Healthy Aging, Universitätsklinikum Dresden, Dresden, Germany
| | - Heike Heuer
- Klinik für Endokrinologie, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Martina Rauner
- Department of Medicine III, Universitätsklinikum Dresden, Dresden, Germany
- Center for Healthy Aging, Universitätsklinikum Dresden, Dresden, Germany
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8
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Salveridou E, Mayerl S, Sundaram SM, Markova B, Heuer H. Tissue-Specific Function of Thyroid Hormone Transporters: New Insights from Mouse Models. Exp Clin Endocrinol Diabetes 2019; 128:423-427. [PMID: 31724131 DOI: 10.1055/a-1032-8328] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Thyroid hormone (TH) transporters are required for cellular transmembrane passage of TH and are thus mandatory for proper TH metabolism and action. Consequently, inactivating mutations in TH transporters such as MCT8 or OATP1C1 can cause tissue- specific changes in TH homeostasis. As the most prominent example, patients with MCT8 mutations exhibit elevated serum T3 levels, whereas their CNS appear to be in a TH deficient state. Here, we will briefly summarize recent studies of mice lacking Mct8 alone or in combination with the TH transporters Mct10 or Oatp1c1 that shed light on many aspects and pathogenic events underlying global MCT8 deficiency and also underscore the contribution of Mct10 and Oatp1c1 in tissue-specific TH transport processes. Moreover, development of conditional knock-out mice that allow a cell-specific inactivation of TH transporters in distinct tissues, disclosed cell-specific changes in TH signaling, thereby highlighting the pathophysiological significance of local control of TH action.
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Affiliation(s)
- Eva Salveridou
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany.,Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Steffen Mayerl
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany.,MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Sivaraj Mohana Sundaram
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany.,Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Boyka Markova
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany.,Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany.,Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
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9
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Leitch VD, Brassill MJ, Rahman S, Butterfield NC, Ma P, Logan JG, Boyde A, Evans H, Croucher PI, Batterham RL, Williams GR, Bassett JHD. PYY is a negative regulator of bone mass and strength. Bone 2019; 127:427-435. [PMID: 31306808 PMCID: PMC6715792 DOI: 10.1016/j.bone.2019.07.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/03/2019] [Accepted: 07/11/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Bone loss in anorexia nervosa and following bariatric surgery is associated with an elevated circulating concentration of the gastrointestinal, anorexigenic hormone, peptide YY (PYY). Selective deletion of the PYY receptor Y1R in osteoblasts or Y2R in the hypothalamus results in high bone mass, but deletion of PYY in mice has resulted in conflicting skeletal phenotypes leading to uncertainty regarding its role in the regulation of bone mass. As PYY analogs are under development for treatment of obesity, we aimed to clarify the relationship between PYY and bone mass. METHODS The skeletal phenotype of Pyy knockout (KO) mice was investigated during growth (postnatal day P14) and adulthood (P70 and P186) using X-ray microradiography, micro-CT, back-scattered electron scanning electron microscopy (BSE-SEM), histomorphometry and biomechanical testing. RESULTS Bones from juvenile and Pyy KO mice were longer (P < 0.001), with decreased bone mineral content (P < 0.001). Whereas, bones from adult Pyy KO mice had increased bone mineral content (P < 0.05) with increased mineralisation of both cortical (P < 0.001) and trabecular (P < 0.001) compartments. Long bones from adult Pyy KO mice were stronger (maximum load P < 0.001), with increased stiffness (P < 0.01) and toughness (P < 0.05) compared to wild-type (WT) control mice despite increased cortical vascularity and porosity (P < 0.001). The increased bone mass and strength in Pyy KO mice resulted from increases in trabecular (P < 0.01) and cortical bone formation (P < 0.05). CONCLUSIONS These findings demonstrate that PYY acts as a negative regulator of osteoblastic bone formation, implicating increased PYY levels in the pathogenesis of bone loss during anorexia or following bariatric surgery.
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Affiliation(s)
- Victoria D Leitch
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom
| | - Mary Jane Brassill
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom
| | - Sofia Rahman
- Centre for Obesity Research, University College London, London WC1E 6JF, United Kingdom
| | - Natalie C Butterfield
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom
| | - Pattara Ma
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom
| | - John G Logan
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom
| | - Alan Boyde
- Queen Mary University of London, Oral BioEngineering, Bart's and The London School of Medicine and Dentistry, London E1 4NS, United Kingdom
| | - Holly Evans
- Sheffield Myeloma Research Team, University of Sheffield, Sheffield S10 2RX, United Kingdom
| | - Peter I Croucher
- The Garvan Institute of Medical Research and St. Vincent's Clinical School, University of New South Wales Medicine, Sydney, New South Wales 2010, Australia
| | - Rachel L Batterham
- Centre for Obesity Research, University College London, London WC1E 6JF, United Kingdom; National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London Q1T 7DN, United Kingdom
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom.
| | - J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Medicine, Hammersmith Campus, Imperial College London, London W12 0NN, United Kingdom.
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10
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Bianco AC, Dumitrescu A, Gereben B, Ribeiro MO, Fonseca TL, Fernandes GW, Bocco BMLC. Paradigms of Dynamic Control of Thyroid Hormone Signaling. Endocr Rev 2019; 40:1000-1047. [PMID: 31033998 PMCID: PMC6596318 DOI: 10.1210/er.2018-00275] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/15/2019] [Indexed: 12/17/2022]
Abstract
Thyroid hormone (TH) molecules enter cells via membrane transporters and, depending on the cell type, can be activated (i.e., T4 to T3 conversion) or inactivated (i.e., T3 to 3,3'-diiodo-l-thyronine or T4 to reverse T3 conversion). These reactions are catalyzed by the deiodinases. The biologically active hormone, T3, eventually binds to intracellular TH receptors (TRs), TRα and TRβ, and initiate TH signaling, that is, regulation of target genes and other metabolic pathways. At least three families of transmembrane transporters, MCT, OATP, and LAT, facilitate the entry of TH into cells, which follow the gradient of free hormone between the extracellular fluid and the cytoplasm. Inactivation or marked downregulation of TH transporters can dampen TH signaling. At the same time, dynamic modifications in the expression or activity of TRs and transcriptional coregulators can affect positively or negatively the intensity of TH signaling. However, the deiodinases are the element that provides greatest amplitude in dynamic control of TH signaling. Cells that express the activating deiodinase DIO2 can rapidly enhance TH signaling due to intracellular buildup of T3. In contrast, TH signaling is dampened in cells that express the inactivating deiodinase DIO3. This explains how THs can regulate pathways in development, metabolism, and growth, despite rather stable levels in the circulation. As a consequence, TH signaling is unique for each cell (tissue or organ), depending on circulating TH levels and on the exclusive blend of transporters, deiodinases, and TRs present in each cell. In this review we explore the key mechanisms underlying customization of TH signaling during development, in health and in disease states.
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Affiliation(s)
- Antonio C Bianco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Alexandra Dumitrescu
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Miriam O Ribeiro
- Developmental Disorders Program, Center of Biologic Sciences and Health, Mackenzie Presbyterian University, São Paulo, São Paulo, Brazil
| | - Tatiana L Fonseca
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Gustavo W Fernandes
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Barbara M L C Bocco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
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11
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Veldscholte K, Barjaktarovic M, Trajanoska K, Jaddoe VWV, Visser TJ, de Rijke YB, Peeters RP, Rivadeneira F, Korevaar TIM. The Association of Thyroid Function With Bone Density During Childhood. J Clin Endocrinol Metab 2018; 103:4125-4134. [PMID: 30020476 DOI: 10.1210/jc.2018-00294] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 07/12/2018] [Indexed: 11/19/2022]
Abstract
CONTEXT Although the skeleton is a well-known thyroid hormone target organ, very little data are available on the association of thyroid function with bone outcomes during childhood. OBJECTIVE To study the association of thyroid function with bone mass during childhood. DESIGN, SETTING, AND PARTICIPANTS Population-based prospective cohort including 4204 children with TSH and free T4 (FT4) measured at the age of 6 years. MAIN OUTCOME MEASURES Bone density was assessed by a total body dual-energy X-ray absorptiometry scan at the median age of 6 years (95% range, 5.6 to 7.9) and at the age of 10 years (95% range, 9.0 to 10.9) in 4204 and 3404 participants, respectively. RESULTS There was an inverse association of TSH with bone mineral density (BMD) at the age of 6 (β -0.028 ± 0.011, P = 0.009) and with follow-up measurements at the age of 10 (β -0.027 ± 0.011, P = 0.014), but not with bone mineral content (BMC) at the age of 6 (β -0.028 ± 0.015, P = 0.06) or for follow-up measurements of BMC at the age of 10 (β -0.011 ± 0.015, P = 0.47). There was an inverse association of FT4 with BMD (β -0.016 ± 0.006, P = 0.014) and BMC (β -0.023 ± 0.009, P = 0.009) cross-sectionally, and also at the age of 10 years (BMD: β -0.018 ± 0.007, P = 0.007; BMC: β -0.021 ± 0.009, P = 0.020). CONCLUSION A higher FT4 concentration is associated with lower bone mass at the age of 6 and at the age of 10 years. These data provide insights into the effects of thyroid function on bone physiology during childhood.
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Affiliation(s)
- Karlien Veldscholte
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- The Generation R. Study Group, Erasmus Medical Center and Sophia Children's Hospital, GE Rotterdam, Netherlands
- Academic Center for Thyroid Diseases, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Mirjana Barjaktarovic
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- The Generation R. Study Group, Erasmus Medical Center and Sophia Children's Hospital, GE Rotterdam, Netherlands
- Academic Center for Thyroid Diseases, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Katerina Trajanoska
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- Department of Epidemiology, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Vincent W V Jaddoe
- The Generation R. Study Group, Erasmus Medical Center and Sophia Children's Hospital, GE Rotterdam, Netherlands
- Department of Epidemiology, Erasmus Medical Center, GE Rotterdam, Netherlands
- Department of Pediatrics, Erasmus Medical Center, Sophia Children's Hospital, GE Rotterdam, Netherlands
| | - Theo J Visser
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- Academic Center for Thyroid Diseases, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Yolanda B de Rijke
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- Department of Clinical Chemistry, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Robin P Peeters
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- The Generation R. Study Group, Erasmus Medical Center and Sophia Children's Hospital, GE Rotterdam, Netherlands
- Academic Center for Thyroid Diseases, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Fernando Rivadeneira
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- Department of Epidemiology, Erasmus Medical Center, GE Rotterdam, Netherlands
| | - Tim I M Korevaar
- Department of Internal Medicine, Erasmus Medical Center, GE Rotterdam, Netherlands
- The Generation R. Study Group, Erasmus Medical Center and Sophia Children's Hospital, GE Rotterdam, Netherlands
- Academic Center for Thyroid Diseases, Erasmus Medical Center, GE Rotterdam, Netherlands
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