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Dore R, Sentis SC, Johann K, Lopez-Alcantara N, Resch J, Chandrasekar A, Müller-Fielitz H, Moeller LC, Fuehrer D, Schwaninger M, Obermayer B, Opitz R, Mittag J. Partial Resistance to Thyroid Hormone-Induced Tachycardia and Cardiac Hypertrophy in Mice Lacking Thyroid Hormone Receptor β. Thyroid 2024. [PMID: 38526409 DOI: 10.1089/thy.2023.0638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Background: Thyroid hormones regulate cardiac functions mainly through direct actions in the heart and by binding to the thyroid hormone receptor (TR) isoforms α1 and β. While the role of the most abundantly expressed isoform, TRα1, is widely studied and well characterized, the role of TRβ in regulating heart functions is still poorly understood, primarily due to the accompanying elevation of circulating thyroid hormone in TRβ knockout mice (TRβ-KO). However, their hyperthyroidism is ameliorated at thermoneutrality, which allows studying the role of TRβ without this confounding factor. Methods: Here, we noninvasively monitored heart rate in TRβ-KO mice over several days using radiotelemetry at different housing temperatures (22°C and 30°C) and upon 3,3',5-triiodothyronine (T3) administration in comparison to wild-type animals. Results: TRβ-KO mice displayed normal average heart rate at both 22°C and 30°C with only minor changes in heart rate frequency distribution, which was confirmed by independent electrocardiogram recordings in freely-moving conscious mice. Parasympathetic nerve activity was, however, impaired in TRβ-KO mice at 22°C, and only partly rescued at 30°C. As expected, oral treatment with pharmacological doses of T3 at 30°C led to tachycardia in wild-types, accompanied by broader heart rate frequency distribution and increased heart weight. The TRβ-KO mice, in contrast, showed blunted tachycardia, as well as resistance to changes in heart rate frequency distribution and heart weight. At the molecular level, these observations were paralleled by a blunted cardiac mRNA induction of several important genes, including the pacemaker channels Hcn2 and Hcn4, as well as Kcna7. Conclusions: The phenotyping of TRβ-KO mice conducted at thermoneutrality allows novel insights on the role of TRβ in cardiac functions in the absence of the usual confounding hyperthyroidism. Even though TRβ is expressed at lower levels than TRα1 in the heart, our findings demonstrate an important role for this isoform in the cardiac response to thyroid hormones.
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Affiliation(s)
- Riccardo Dore
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Sarah Christine Sentis
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Kornelia Johann
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Nuria Lopez-Alcantara
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Julia Resch
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Akila Chandrasekar
- Institute for Experimental and Clinical Pharmacology and Toxicology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Helge Müller-Fielitz
- Institute for Experimental and Clinical Pharmacology and Toxicology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Lars Christian Moeller
- Department of Endocrinology, Diabetes and Metabolism, and Division of Laboratory Research, University of Duisburg-Essen, Essen, Germany
| | - Dagmar Fuehrer
- Department of Endocrinology, Diabetes and Metabolism, and Division of Laboratory Research, University of Duisburg-Essen, Essen, Germany
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
| | - Benedikt Obermayer
- Core Unit Bioinformatics, Berlin Institute of Health at Charité, Universitätsmedizin Berlin, Berlin, Germany
| | - Robert Opitz
- Institute of Experimental Pediatric Endocrinology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jens Mittag
- Institute for Experimental Endocrinology, Center of Brain Behavior & Metabolism, University of Lübeck, Lübeck, Germany
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Miranda RA, de Moura EG, Lisboa PC. Adverse perinatal conditions and the developmental origins of thyroid dysfunction-Lessons from Animal Models. Endocrine 2023; 79:223-234. [PMID: 36036880 DOI: 10.1007/s12020-022-03177-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/17/2022] [Indexed: 02/04/2023]
Abstract
PURPOSE Nutritional, hormonal, and environmental status during development can predispose the individual to obesity and endocrine diseases later in life, an association known as metabolic programming. In general, weight loss or gain are seen in thyroid disorders, and thyroid function can be affected by body adiposity. In addition, hyper- and hypothyroidism can be related to metabolic programming. Our aim was to gather evidence that regardless of the type or critical window of metabolic imprinting, offspring exposed to certain adverse perinatal conditions have a higher risk of developing thyroid dysfunction. METHODS We reviewed literature data that relate insults occurring during pregnancy and/or lactation to short- and long-term offspring thyroid dysfunction in animal models. RESULTS Few studies have addressed the hypothalamic-pituitary-thyroid axis and thyroid dysfunction related to metabolic programming. The literature shows that under- and overnutrition, exposure to endocrine disruptors, early weaning, maternal thyroid disease and maternal high-fat diet can induce alterations in offspring thyroid function in a sex-dependent manner. CONCLUSION Based on the few available data, mainly in rodent models, we can conclude that diet, hormones, and environmental contaminants are related to the developmental origins of later thyroid dysfunction by interrupting the normal maturation of the thyroid gland.
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Affiliation(s)
- Rosiane Aparecida Miranda
- Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Egberto Gaspar de Moura
- Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Patrícia Cristina Lisboa
- Laboratory of Endocrine Physiology, Department of Physiological Sciences, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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Paisdzior S, Schuelke M, Krude H. What is the Role of Thyroid Hormone Receptor Alpha 2 (TRα2) in Human Physiology? Exp Clin Endocrinol Diabetes 2022; 130:296-302. [PMID: 35255520 DOI: 10.1055/a-1716-7980] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Thyroid hormone receptors are nuclear receptors that function as transcription factors and are regulated by thyroid hormones. To date, a number of variants and isoforms are known. This review focuses on the thyroid hormone receptor α (TRα), in particular TRα2, an isoform that arises from alternative splicing of the THRA mRNA transcript. Unlike the TRα1 isoform, which can bind T3, the TRα2 isoform lacks a ligand-binding domain but still binds to DNA thereby antagonizing the transcriptional activity of TRα1. Although a regulatory role has been proposed, the physiological function of this TRα2 antagonism is still unclear due to limited in vitro and mouse model data. Recently, the first patients with resistance to thyroid hormone due to mutations in THRA, the TRα encoding gene, affecting the antagonistic function of TRα2 were described, suggesting a significant role of this particular isoform in human physiology.
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Affiliation(s)
- Sarah Paisdzior
- Institute of Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Markus Schuelke
- NeuroCure Cluster of Excellence; Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.,Department of Neuropediatrics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Heiko Krude
- Institute of Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
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4
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de Vries EM, Surovtseva O, Vos WG, Kunst RF, van Beeren M, Kwakkel J, Chassande O, Ackermans MT, Fliers E, Boelen A. Downregulation of Type 3 Deiodinase in the Hypothalamus During Inflammation. Thyroid 2019; 29:1336-1343. [PMID: 31303139 DOI: 10.1089/thy.2019.0201] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Background: Inflammation is associated with marked changes in cellular thyroid hormone (TH) metabolism in triiodothyronine (T3) target organs. In the hypothalamus, type 2 deiodinase (D2), the main T3 producing enzyme, increases upon inflammation, leading to an increase in local T3 availability, which in turn decreases thyrotropin releasing hormone expression in the paraventricular nucleus. Type 3 deiodinase (D3), the T3 inactivating enzyme, decreases during inflammation, which might also contribute to the increased T3 availability in the hypothalamus. While it is known that D2 is regulated by nuclear factor κB (NF-κB) during inflammation, the underlying mechanisms of D3 regulation are unknown. Therefore, the aim of the present study was to investigate inflammation-induced D3 regulation using in vivo and in vitro models. Methods: Mice were injected with a sublethal dose of bacterial endotoxin (lipopolysaccharide [LPS]) to induce a systemic acute-phase response. A human neuroblastoma (SK-N-AS) cell line was used to test the involvement of the thyroid hormone receptor alpha 1 (TRα1) as well as the activator protein-1 (AP-1) and NF-κB inflammatory pathways in the inflammation-induced decrease of D3. Results: D3 expression in the hypothalamus was decreased 24 hours after LPS injection in mice. This decrease was similar in mice lacking the TRα. Incubation of SK-N-AS cells with LPS robustly decreased both D3 mRNA expression and activity. This led to increased intracellular T3 concentrations. The D3 decrease was prevented when NF-κB or AP-1 was inhibited. TRα1 mRNA expression decreased in SK-N-AS cells incubated with LPS, but knockdown of the TRα in SK-N-AS cells did not prevent the LPS-induced D3 decrease. Conclusions: We conclude that the inflammation-induced D3 decrease in the hypothalamus is mediated by the inflammatory pathways NF-κB and AP-1, but not TRα1. Furthermore, the observed decrease modulates intracellular T3 concentrations. Our results suggest a concerted action of inflammatory modulators to regulate both hypothalamic D2 and D3 activities to increase the local TH concentrations.
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Affiliation(s)
- Emmely M de Vries
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Olga Surovtseva
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Winnie G Vos
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Roni F Kunst
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Mieke van Beeren
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Joan Kwakkel
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Olivier Chassande
- Tissue Bioengineering, U1026, F-33076, University of Bordeaux, Bordeaux, France
| | - Mariette T Ackermans
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Eric Fliers
- Department of Endocrinology and Metabolism, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Anita Boelen
- Endocrine Laboratory, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Department of Endocrinology and Metabolism, Research Institute Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
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5
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López Navarro E, Ortega FJ, Francisco-Busquets E, Sabater-Masdeu M, Álvarez-Castaño E, Ricart W, Fernández-Real JM. Thyroid Hormone Receptors Are Differentially Expressed in Granulosa and Cervical Cells of Infertile Women. Thyroid 2016; 26:466-73. [PMID: 26715425 DOI: 10.1089/thy.2015.0416] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Thyroid hormones are known to exert an important role in reproduction. The objective of this study was to evaluate the expression of thyroid hormone receptors (TR) in granulosa (GC) and cervical cells (CC) of infertile euthyroid women. METHODS In a cross-sectional study, 31 consecutive infertile and 18 fertile women undergoing oocyte retrieval procedures were investigated. The expression of TRα1, TRα2, and TRβ was evaluated in GCs and uterine CC from infertile and fertile euthyroid women. β2 adrenergic receptor (ADRβ2) mRNA levels and the expression of genes linked to fertility such as gremlin-1 (GREM1), hyaluronan synthase 2 (HAS2), and prostaglandin-endoperoxide synthase 2 (PTGS2) were also evaluated. RESULTS In GCs, the expression of the thyroid hormone receptor TRα2, which exerts a dominant negative effect, increased with age in all women tested. TRα2 mRNA was increased in infertile versus fertile women, in parallel to decreased ADRβ2 mRNA. As expected, the expression of genes associated with fertility (i.e., GREM1 and PTGS2) was downregulated in infertile women, in parallel to decreased ADRβ2 mRNA and increased TRα2 mRNA. In uterine CCs, a positive association of ADRβ2 mRNA with TRα1:TRα2 ratio was observed. Importantly, GCs from infertile women whose oocytes did not result in pregnancy had increased expression of TRα2 (p = 0.017) and lower ADRβ2 (p = 0.008), GREM1 (p = 0.003), and PTGS2 (p = 0.002) mRNAs than fertile women whose oocytes resulted in pregnancy. Infertile women also showed more TRα2 (p = 0.033) mRNA in CCs than fertile women whose oocytes resulted in pregnancy. CONCLUSIONS The expression of different markers of intracellular thyroid function is linked to fertility status.
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Affiliation(s)
- Eva López Navarro
- 1 Obstetrics and Gynecology Service, Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
| | - Francisco J Ortega
- 2 Department of Diabetes, Endocrinology, and Nutrition (UDEN), Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
- 3 CIBERobn Pathophysiology of Obesity and Nutrition, Instituto de Salud Carlos III, Madrid, Spain
| | | | - Mònica Sabater-Masdeu
- 2 Department of Diabetes, Endocrinology, and Nutrition (UDEN), Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
- 3 CIBERobn Pathophysiology of Obesity and Nutrition, Instituto de Salud Carlos III, Madrid, Spain
| | - Elena Álvarez-Castaño
- 1 Obstetrics and Gynecology Service, Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
| | - Wifredo Ricart
- 2 Department of Diabetes, Endocrinology, and Nutrition (UDEN), Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
- 3 CIBERobn Pathophysiology of Obesity and Nutrition, Instituto de Salud Carlos III, Madrid, Spain
| | - José M Fernández-Real
- 2 Department of Diabetes, Endocrinology, and Nutrition (UDEN), Institut d'Investigació Biomèdica de Girona (IdIBGi) , Girona, Spain
- 3 CIBERobn Pathophysiology of Obesity and Nutrition, Instituto de Salud Carlos III, Madrid, Spain
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Liu KL, Lo M, Canaple L, Gauthier K, del Carmine P, Beylot M. Vascular Function of the Mesenteric Artery Isolated from Thyroid Hormone Receptor-E Knockout Mice. J Vasc Res 2014; 51:350-9. [DOI: 10.1159/000368195] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 08/14/2014] [Indexed: 11/19/2022] Open
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Yuan PQ, Yang H. Hypothyroidism increases Fos immunoreactivity in cholinergic neurons of brain medullary dorsal vagal complex in rats. Am J Physiol Endocrinol Metab 2005; 289:E892-9. [PMID: 15985455 DOI: 10.1152/ajpendo.00108.2005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypo- or hyperthyroidism is associated with autonomic disorders. We studied Fos expression in the medullary dorsal motor nucleus of the vagus (DMV), nucleus tractus solitarii (NTS), and area postrema (AP) in four groups of rats with different thyroid states induced by a combination of drinking water and daily intraperitoneal injection for 1-4 wk: 1) tap water and vehicle; 2) 0.1% propylthiouracil (PTU) and vehicle; 3) PTU and thyroxine (T4; 2 microg/100 g); and 4) tap water and T4 (10 microg/100 g). The numbers of Fos immunoreactive (IR) positive neurons in the DMV, NTS, and AP were low in euthyroid rats but significantly higher in the 4-wk duration in hypothyroid rats, which were prevented by simultaneous T4 replacement. Hyperthyroidism had no effect on Fos expression in these areas. There were significant negative correlations between T4 levels and the numbers of Fos-IR-positive neurons in the DMV (r = -0.6388, P < 0.008), NTS (r = -0.6741, P < 0.003), and AP (r = -0.5622, P < 0.004). Double staining showed that Fos immunoreactivity in the DMV of hypothyroid rats was mostly localized in choline acetyltransferase-containing neurons. Thyroid hormone receptors alpha1 and beta2 were localized in the observed nuclei. These results indicate that thyroid hormone influences the DMV/NTS/AP neuronal activity, which may contribute to the vagal-related visceral disorders observed in hypothyroidism.
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Affiliation(s)
- Pu-Qing Yuan
- CURE: Digestive Diseases Research Center, Veterans Affairs Greater Los Angeles Healthcare System, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA
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Vallejo CG, Seguido AM, Testillano PS, Risueño MC. Thyroid hormone regulates tubulin expression in mammalian liver. Effects of deleting thyroid hormone receptor-alpha or -beta. Am J Physiol Endocrinol Metab 2005; 289:E87-94. [PMID: 15713690 DOI: 10.1152/ajpendo.00436.2004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Microtubules are made from polymers of alpha/beta dimers. We have observed in rat liver that, on the first day after birth, alpha-subunit is relatively high and beta-subunit low with respect to adult values. In the hypothyroid neonate, both subunits were found to be low, therefore indicating that thyroid hormone (TH) regulates these developmental changes. TH was also found to activate tubulin expression in adult liver, especially beta-subunit. To investigate the role of TH receptors (TRs) in tubulin expression, we analyzed mice lacking TRalpha or TRbeta compared with the wild type in both normal and TH-deprived adult animals. The results suggest that, in vivo, beta-tubulin protein expression in the liver is primarily under TRbeta positive control. In euthyroid mice lacking TRbeta, beta-tubulin expression was low. However, in the corresponding hypothyroid animals, it was found increased, therefore suggesting that the unliganded TRalpha might also upregulate beta-tubulin expression. Accordingly, TH administration to hypothyroid TRbeta-deprived mice reduced their high beta-tubulin expression. In parallel, the relatively high messenger level observed with these hypothyroid animals was reduced to the euthyroid level after T(3) treatment. The microtubular network of the mutant livers appeared, by immunofluorescence confocal microscopy, generally disorganized and drastically reduced in beta-tubulin in mice lacking TRbeta. In conclusion, our results indicate that beta-tubulin is critically controlled by TRbeta in the liver and that both TRs are probably needed to maintain the microtubular network organization of the liver.
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Affiliation(s)
- Carmen G Vallejo
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Arturo Duperier, 4, 28029 Madrid, Spain.
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Morte B, Manzano J, Scanlan T, Vennström B, Bernal J. Deletion of the thyroid hormone receptor alpha 1 prevents the structural alterations of the cerebellum induced by hypothyroidism. Proc Natl Acad Sci U S A 2002; 99:3985-9. [PMID: 11891331 PMCID: PMC122635 DOI: 10.1073/pnas.062413299] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Thyroid hormone (T3) controls critical aspects of cerebellar development, such as migration of postmitotic granule cells and terminal differentiation of Purkinje cells. T3 acts through nuclear receptors (TR) of two types, TRalpha1 and TRbeta, that either repress or activate gene expression. We have analyzed the cerebellar structure of developing mice lacking the TRalpha1 isoform, which normally accounts for about 80% of T3 receptors in the cerebellum. Contrary to what was expected, granule cell migration and Purkinje cell differentiation were normal in the mutant mice. Even more striking was the fact that when neonatal hypothyroidism was induced, no alterations in cerebellar structure were observed in the mutant mice, whereas the wild-type mice showed delayed granule cell migration and arrested Purkinje cell growth. The results support the idea that repression by the TRalpha1 aporeceptor, and not the lack of thyroid hormone, is responsible for the hypothyroid phenotype. This conclusion was supported by experiments with the TRbeta-selective compound GC-1. Treatment of hypothyroid animals with T3, which binds to TRalpha1 and TRbeta, prevents any defect in cerebellar structure. In contrast, treatment with GC-1, which binds to TRbeta but not TRalpha1, partially corrects Purkinje cell differentiation but has no effect on granule cell migration. Our data indicate that thyroid hormone has a permissive effect on cerebellar granule cell migration through derepression by the TRalpha1 isoform.
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Affiliation(s)
- Beatriz Morte
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, Arturo Duperier 4, 28029 Madrid, Spain
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Kaneshige M, Suzuki H, Kaneshige K, Cheng J, Wimbrow H, Barlow C, Willingham MC, Cheng S. A targeted dominant negative mutation of the thyroid hormone alpha 1 receptor causes increased mortality, infertility, and dwarfism in mice. Proc Natl Acad Sci U S A 2001; 98:15095-100. [PMID: 11734632 PMCID: PMC64989 DOI: 10.1073/pnas.261565798] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2001] [Accepted: 10/23/2001] [Indexed: 11/18/2022] Open
Abstract
Mutations in the thyroid hormone receptor beta (TRbeta) gene result in resistance to thyroid hormone. However, it is unknown whether mutations in the TRalpha gene could lead to a similar disease. To address this question, we prepared mutant mice by targeting mutant thyroid hormone receptor kindred PV (PV) mutation to the TRalpha gene locus by means of homologous recombination (TRalpha1PV mice). The PV mutation was derived from a patient with severe resistance to thyroid hormone that has a frameshift of the C-terminal 14 aa of TRbeta1. We knocked in the same PV mutation to the corresponding TRalpha gene locus to compare the phenotypes of TRalpha1(PV/+) mice with those of TRbeta(PV/+) mice. TRalpha1(PV/+) mice were viable, indicating that the mutation of the TRalpha gene is not embryonic lethal. In drastic contrast to the TRbeta(PV/+) mice, which do not exhibit a growth abnormality, TRalpha1(PV/+) mice were dwarfs. These dwarfs exhibited increased mortality and reduced fertility. In contrast to TRbeta(PV/+) mice, which have a hyperactive thyroid, TRalpha1(PV/+) mice exhibited mild thyroid failure. The in vivo pattern of abnormal regulation of T3 target genes in TRalpha1(PV/+) mice was unique from those of TRbeta(PV/+) mice. The distinct phenotypes exhibited by TRalpha1(PV/+) and TRbeta(PV/+) mice indicate that the in vivo functions of TR mutants are isoform-dependent. The TRalpha1(PV/+) mice may be used as a tool to uncover human diseases associated with mutations in the TRalpha gene and, furthermore, to understand the molecular mechanisms by which TR isoforms exert their biological activities.
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Affiliation(s)
- M Kaneshige
- Laboratory of Molecular Biology, National Cancer Institute, Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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