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Niederkinkhaus V, Marx R, Hoffmann G, Dietzel ID. Thyroid hormone (T3)-induced up-regulation of voltage-activated sodium current in cultured postnatal hippocampal neurons requires secretion of soluble factors from glial cells. Mol Endocrinol 2009; 23:1494-504. [PMID: 19460859 DOI: 10.1210/me.2009-0132] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We have previously shown that treatment with the thyroid hormone T(3) increases the voltage-gated Na(+)current density (Nav-D) in hippocampal neurons from postnatal rats, leading to accelerated action potential upstrokes and increased firing frequencies. Here we show that the Na(+) current regulation depends on the presence of glial cells, which secrete a heat-instable soluble factor upon stimulation with T(3). The effect of conditioned medium from T(3)-treated glial cells was mimicked by basic fibroblast growth factor (bFGF), known to be released from cerebellar glial cells after T(3) treatment. Neutralization assays of astrocyte-conditioned media with anti-bFGF antibody inhibited the regulation of the Nav-D by T(3). This suggests that the up-regulation of the neuronal sodium current density by T(3) is not a direct effect but involves bFGF release and satellite cells. Thus glial cells can modulate neuronal excitability via secretion of paracrinely acting factors.
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Affiliation(s)
- Vanessa Niederkinkhaus
- Department of Molecular Neurobiochemistry, Ruhr-University Bochum, NC7-170, Universitätsstrasse 150, D-44780 Bochum, Germany
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Lassová L, Niu Z, Golden EB, Cohen AJ, Adams SL. Thyroid hormone treatment of cultured chondrocytes mimics in vivo stimulation of collagen X mRNA by increasing BMP 4 expression. J Cell Physiol 2009; 219:595-605. [PMID: 19170125 DOI: 10.1002/jcp.21704] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
During endochondral bone formation, chondrocytes undergo terminal differentiation, during which the rate of proliferation decreases, cells become hypertrophic, and the extracellular matrix is altered by production of collagen X, as well as proteins required for matrix mineralization. This maturation process is responsible for most longitudinal bone growth, both during embryonic development and in postnatal long bone growth plates. Among the major signaling molecules implicated in regulation of this process are the positive regulators thyroid hormone (T3) and bone morphogenetic proteins (BMPs). Both T3 and BMPs are essential for endochondral bone formation and cannot compensate for each other, suggesting interaction of the two signaling pathways. We have analyzed the temporal and spatial expression patterns of numerous genes believed to play a role in chondrocyte maturation. Our results show that T3 stimulates collagen X gene expression in cultured chondrocytres with kinetics and magnitude similar to those observed in vivo. Stimulation of collagen X gene expression by T3 occurs only after a significant delay, implying that this hormone may act indirectly. We show further that T3 rapidly stimulates production of BMP 4, concomitant with a decrease in the BMP inhibitor Noggin, potentially resulting in a net increase in BMP signaling. Finally, inhibition of BMP signaling with exogenous Noggin prevents T3 stimulation of collagen X expression, indicating that BMP signaling is essential for this process. These data position thyroid hormone at the top of a T3/BMP cascade, potentially explaining why both pathways are essential for chondrocyte maturation. J. Cell. Physiol. 219: 595-605, 2009. (c) 2009 Wiley-Liss, Inc.
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Affiliation(s)
- Luisa Lassová
- Department of Biochemistry, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA.
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Use of a new model of transgenic mice to clarify the respective functions of thyroid hormone receptors in vivo. Heart Fail Rev 2009; 15:117-20. [DOI: 10.1007/s10741-008-9121-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Accepted: 10/21/2008] [Indexed: 10/21/2022]
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Williams AJ, Robson H, Kester MHA, van Leeuwen JPTM, Shalet SM, Visser TJ, Williams GR. Iodothyronine deiodinase enzyme activities in bone. Bone 2008; 43:126-134. [PMID: 18468505 PMCID: PMC2681075 DOI: 10.1016/j.bone.2008.03.019] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 03/12/2008] [Accepted: 03/16/2008] [Indexed: 12/02/2022]
Abstract
Euthyroid status is essential for normal skeletal development and maintenance of the adult skeleton, but the mechanisms which control supply of thyroid hormone to bone cells are poorly understood. Thyroid hormones enter target cells via monocarboxylate transporter-8 (MCT8), which provides a functional link between thyroid hormone uptake and metabolism in the regulation of T3-action but has not been investigated in bone. Most circulating active thyroid hormone (T3) is derived from outer ring deiodination of thyroxine (T4) mediated by the type 1 deiodinase enzyme (D1). The D2 isozyme regulates intra-cellular T3 supply and determines saturation of the nuclear T3-receptor (TR), whereas a third enzyme (D3) inactivates T4 and T3 to prevent hormone availability and reduce TR-saturation. The aim of this study was to determine whether MCT8 is expressed in the skeleton and whether chondrocytes, osteoblasts and osteoclasts express functional deiodinases. Gene expression was analyzed by RT-PCR and D1, D2 and D3 function by sensitive and highly specific determination of enzyme activities. MCT8 mRNA was expressed in chondrocytes, osteoblasts and osteoclasts at all stages of cell differentiation. D1 activity was undetectable in all cell types, D2 activity was only present in mature osteoblasts whereas D3 activity was evident throughout chondrocyte, osteoblast and osteoclast differentiation in primary cell cultures. These data suggest that T3 availability especially during skeletal development may be limited by D3-mediated catabolism rather than by MCT8 mediated cellular uptake or D2-dependent T3 production.
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Affiliation(s)
- Allan J Williams
- Molecular Endocrinology Group, Division of Medicine and Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, London W12 0NN, UK
| | - Helen Robson
- Department of Clinical Research, Christie Hospital National Health Service (NHS) Trust, Manchester, M20 4BX, UK; Cancer Tissue Bank Research Centre, Department of Pathology, Duncan Building, University of Liverpool, Daulby Street, L69 3GA, UK
| | - Monique H A Kester
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, The Netherlands
| | | | - Stephen M Shalet
- Department of Endocrinology, Christie Hospital NHS Trust, Manchester, M20 4BX, UK
| | - Theo J Visser
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, The Netherlands
| | - Graham R Williams
- Molecular Endocrinology Group, Division of Medicine and Medical Research Council (MRC) Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, London W12 0NN, UK.
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55
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Mueller MB, Tuan RS. Functional characterization of hypertrophy in chondrogenesis of human mesenchymal stem cells. ACTA ACUST UNITED AC 2008; 58:1377-88. [PMID: 18438858 DOI: 10.1002/art.23370] [Citation(s) in RCA: 349] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Mesenchymal stem cells (MSCs) are promising candidate cells for cartilage tissue engineering. Expression of cartilage hypertrophy markers (e.g., type X collagen) by MSCs undergoing chondrogenesis raises concern for a tissue engineering application for MSCs, because hypertrophy would result in apoptosis and ossification. To analyze the biologic basis of MSC hypertrophy, we examined the response of chondrifying MSCs to culture conditions known to influence chondrocyte hypertrophy, using an array of hypertrophy-associated markers. METHODS Human MSC pellet cultures were predifferentiated for 2 weeks in a chondrogenic medium, and hypertrophy was induced by withdrawing transforming growth factor beta (TGFbeta), reducing the concentration of dexamethasone, and adding thyroid hormone (T3). Cultures were characterized by histologic, immunohistochemical, and biochemical methods, and gene expression was assessed using quantitative reverse transcription-polymerase chain reaction. RESULTS The combination of TGFbeta withdrawal, a reduction in the level of dexamethasone, and the addition of T3 was essential for hypertrophy induction. Cytomorphologic changes were accompanied by increased alkaline phosphatase activity, matrix mineralization, and changes in various markers of hypertrophy, including type X collagen, fibroblast growth factor receptors 1-3, parathyroid hormone-related protein receptor, retinoic acid receptor gamma, matrix metalloproteinase 13, Indian hedgehog, osteocalcin, and the proapoptotic gene p53. However, hypertrophy was not induced uniformly throughout the pellet culture, and distinct regions of dedifferentiation were observed. CONCLUSION Chondrogenically differentiating MSCs behave in a manner functionally similar to that of growth plate chondrocytes, expressing a very similar hypertrophic phenotype. Under the in vitro culture conditions used here, MSC-derived chondrocytes underwent a differentiation program analogous to that observed during endochondral embryonic skeletal development, with the potential for terminal differentiation. This culture system is applicable for the screening of hypertrophy-inhibitory conditions and agents that may be useful to enhance MSC performance in cartilage tissue engineering.
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Affiliation(s)
- Michael B Mueller
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda 20892-8022, Maryland, USA
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Impact du jeûne intermittent sur la maturation et le remodelage de l’os chez les jeunes rats. NUTR CLIN METAB 2008. [DOI: 10.1016/j.nupar.2008.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Seelig DM, Whittemore JC, Lappin MR, Myers AM, Avery PR. Goitrous hypothyroidism associated with treatment with trimethoprim-sulfamethoxazole in a young dog. J Am Vet Med Assoc 2008; 232:1181-5. [PMID: 18412530 DOI: 10.2460/javma.232.8.1181] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
CASE DESCRIPTION A 16-week-old female Boxer that had been treated for 5 weeks with trimethoprim-sulfamethoxazole and chloramphenicol because of aspiration pneumonia was evaluated for bilaterally symmetric masses in the subcutaneous tissues of the ventral neck, in the region of the larynx. CLINICAL FINDINGS Fine-needle aspirates were obtained from the neck masses; cytologic examination revealed well-differentiated thyroid epithelial tissue. A blood sample was collected for serum biochemical and thyroid function analyses. Mild hyperphosphatemia, severe hypercholesterolemia, mild hyperkalemia, and a mild increase in creatine kinase activity were identified. Serum concentration of total thyroxine was less than the lower reference limit, and that of thyroid-stimulating hormone was greater than the upper reference limit. Findings were consistent with a diagnosis of clinical hypothyroidism in a skeletally immature dog. TREATMENT AND OUTCOME Treatment with trimethoprim-sulfamethoxazole was discontinued. The dog was reevaluated 3 weeks later, at which time the neck masses were markedly decreased in size. Serum concentrations of cholesterol and potassium were lower; serum concentrations of total thyroxine and thyroid-stimulating hormone were near or within respective reference ranges. Age-appropriate increases in serum phosphorus concentration and serum alkaline phosphatase activity were also detected. CLINICAL RELEVANCE To the authors' knowledge, this is the first report of antimicrobial-induced goiter in a dog. Cytologic examination of fine-needle aspirates and interpretation of data from serum biochemical and thyroid function analyses were needed to obtain a definitive diagnosis. Practitioners should include goiter among the differential diagnoses for ventral neck swellings in young dogs receiving potentiated sulfonamide antimicrobials.
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Affiliation(s)
- Davis M Seelig
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
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Ortega E, Koska J, Pannacciulli N, Bunt JC, Krakoff J. Free triiodothyronine plasma concentrations are positively associated with insulin secretion in euthyroid individuals. Eur J Endocrinol 2008; 158:217-21. [PMID: 18230829 PMCID: PMC2408760 DOI: 10.1530/eje-07-0592] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Thyroid hormones (TH) may influence glucose metabolism. Hyperthyroid subjects have higher insulin secretion rates when compared with euthyroid individuals. OBJECTIVE To evaluate the association between TH concentrations and insulin secretion in euthyroid, healthy Pima Indian adults (n=55, 29+/-7 years, females/males 36/19) with normal glucose tolerance (NGT) admitted to a Clinical Research Unit. METHODS TSH, free thyroxine (FT4), 3,5,3'-L-tri-iodothyronine (FT3), and fasting plasma insulin (FPI) concentrations were measured in fasting plasma samples, percentage of body fat (%BF) by dual energy x-ray absorptiometry (DXA), acute insulin response (AIR), and incremental area under the curve (AUC) of insulin in response to a 25 g intravenous glucose tolerance test (IVGTT) and 75 g oral glucose tolerance test (OGTT) respectively and insulin action (M) during an euglycemic clamp. RESULTS FT3 concentrations were associated with FPI, AIR, and insulin AUC both before (r=0.33, P=0.01; r=0.29, P=0.03; and r=0.35, P=0.008 respectively) and after adjustment for age, sex, %BF, glucose (fasting concentrations or glucose AUC), and M (beta=0.09, P=0.01; beta=0.16, P=0.03; and beta=0.24, P=0.0007 respectively). No associations were found for TSH or FT4. CONCLUSION FT3 was associated with several measurements of insulin secretion in euthyroid individuals with NGT. T3 concentrations may play a role in the regulation of insulin secretion.
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Affiliation(s)
- Emilio Ortega
- Obesity and Diabetes Clinical Research Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 4212 North 16th Street, Room 5-35, Phoenix, Arizona 85016, USA.
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Demartini ADA, Kulak CA, Borba VC, Cat MN, Dondoni RS, Sandrini R, Nesi-França S, Lacerda Filho LD. Densidade mineral óssea de crianças e adolescentes com hipotireoidismo congênito. ACTA ACUST UNITED AC 2007; 51:1084-92. [DOI: 10.1590/s0004-27302007000700010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Accepted: 05/28/2007] [Indexed: 11/22/2022]
Abstract
Realizou-se estudo transversal com 60 pacientes (9,9 ± 1,8 anos) com hipotireoidismo congênito (HC) (grupo A): 40 meninas (23 pré-púberes) e 20 meninos (18 pré-púberes), com grupo controle (grupo B) constituído por 28 indivíduos (10,4 ± 2,1 anos): 18 meninas (8 pré-púberes) e 10 meninos (9 pré-púberes). OBJETIVOS: Avaliar a densidade (DMO) e o conteúdo mineral ósseo (CMO) e correlacioná-los com idade cronológica e óssea (IO), sexo, maturação sexual, dose de l-T4, TSH, TT4, FT4, e etiologia do HC. IO, DMO e CMO de corpo total (DXA) foram obtidos dos 2 grupos; TSH, TT4 e FT4, apenas dos pacientes. DMO foi menor no grupo A (0,795 ± 0,075 g/cm² vs. 0,832 ± 0,092; p = 0,04) e maior nas meninas púberes do que nas pré-púberes (p = 0,004). Não houve diferença significativa de DMO e CMO quanto ao sexo e etiologia do HC. Nosso estudo mostra que a DMO foi significativamente menor no grupo com HC, diferente dos dados da literatura.
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Susperreguy S, Miras MB, Montesinos MM, Mascanfroni ID, Muñoz L, Sobrero G, Silvano L, Masini-Repiso AM, Coleoni AH, Targovnik HM, Pellizas CG. Growth hormone (GH) treatment reduces peripheral thyroid hormone action in girls with Turner syndrome. Clin Endocrinol (Oxf) 2007; 67:629-36. [PMID: 17666093 DOI: 10.1111/j.1365-2265.2007.02936.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Turner syndrome (TS) is an indication for GH therapy in spite of the modest growth response. Somatic growth depends not only on GH insulin-like growth factor I (IGF-I) axis but also on thyroid hormone (TH) status. We have previously reported that supraphysiological IGF-I levels diminished TH actions in rat tissues by reducing the nuclear TH receptor (TR). GH treatment to TS patients induces high IGF-I levels and therefore a reduction of TH action in tissues may be expected. We aimed at evaluating the effect of GH therapy in TS girls on peripheral TH action. DESIGN AND PATIENTS We set up a reverse transcription-polymerase chain reaction (RT-PCR) for TR mRNA estimation in peripheral blood mononuclear cells (PBMC) and compared TR mRNA levels from 10 normal, 10 TS and 10 TS girls under GH therapy (0.33 mg/kg/week for 0.5-2 years). MEASUREMENTS After RNA extraction from PBMC, TR and beta-actin mRNAs were coamplified by RT-PCR. In addition serum biochemical markers of TH action were measured: thyrotropin (TSH), sex hormone binding globulin (SHBG), osteocalcin (OC), beta-crosslaps (beta-CL), iodothyronines by electrochemiluminescency and IGF-I by immunoradiometric assay (IRMA) with extraction. RESULTS TR mRNAs from PBMC were reduced in TS patients under GH treatment. In turn, serum TSH, OC, beta-CL and IGF-I were increased while SHBG was reduced by GH treatment in TS patients. CONCLUSIONS GH treatment reduced TR expression in PBMC and biochemical serum markers of TH action. These results suggest that GH treatment in TS patients impair peripheral TH action at tissue level and prompt a role in the reduced growth response to the therapy.
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Affiliation(s)
- S Susperreguy
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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Abstract
This article provides a summary of the numerous interactions between the thyroid gland and the skeleton, in the normal state, in disorders of thyroid function and as a result of thyroid malignancy. It recaps the current understanding of bone growth and development in the endochondral growth plate and the normal mechanisms of mature bone remodeling. The actions of thyroid hormones on these processes are described, and the clinical impact of thyroid disorders and their treatments on the bone are summarized. Finally, our current understanding of the physiology of bone metastases from thyroid cancer is covered.
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Affiliation(s)
- Jason A Wexler
- Division of Endocrinology, MedStar Diabetes and Research Institute, Washington Hospital Center, 110 Irving Street, NW, Room 2A38A, Washington, DC 20010, USA.
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Rasmussen SA, Yazdy MM, Carmichael SL, Jamieson DJ, Canfield MA, Honein MA. Maternal thyroid disease as a risk factor for craniosynostosis. Obstet Gynecol 2007; 110:369-77. [PMID: 17666613 DOI: 10.1097/01.aog.0000270157.88896.76] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To study the relationship between maternal thyroid disease and craniosynostosis using data from the National Birth Defects Prevention Study, a multisite, case-control study. METHODS Case infants (n=431) were identified through population-based birth defects surveillance systems at eight sites and had craniosynostosis verified by radiographic imaging. Control infants (n=4,094) consisted of a random sample of live births with no major birth defects from the same population as the case infants. Information on thyroid disease was based on self-report: mothers who reported either a thyroid disorder or use of a medication to treat a thyroid disorder during pregnancy were considered to have thyroid disease. Using an unconditional logistic regression model, we considered potential confounding factors (maternal age, race or ethnicity, smoking, body mass index, preexisting diabetes, plurality, gravidity, family history, infant sex). RESULTS Among case mothers, 19 (4.4%) were classified as having thyroid disease, compared with 65 (1.6%) of control mothers. Maternal thyroid disease was associated with craniosynostosis after controlling for maternal age (adjusted odds ratio 2.47, 95% confidence interval 1.46-4.18), the only factor that remained significant in the final model. CONCLUSION These data provide additional evidence that maternal thyroid disease (most likely Graves' disease) or its treatment is associated with craniosynostosis. Given the frequency of maternal thyroid disease, this association warrants further investigation. LEVEL OF EVIDENCE II.
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Affiliation(s)
- Sonja A Rasmussen
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA.
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Bassett JHD, Nordström K, Boyde A, Howell PGT, Kelly S, Vennström B, Williams GR. Thyroid Status during Skeletal Development Determines Adult Bone Structure and Mineralization. Mol Endocrinol 2007; 21:1893-904. [PMID: 17488972 DOI: 10.1210/me.2007-0157] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Childhood hypothyroidism delays ossification and bone mineralization, whereas adult thyrotoxicosis causes osteoporosis. To determine how effects of thyroid hormone (T3) during development manifest in adult bone, we characterized TRalpha1(+/m)beta(+/-) mice, which express a mutant T3 receptor (TR) alpha1 with dominant-negative properties due to reduced ligand-binding affinity. Remarkably, adult TRalpha1(+/m)beta(+/-) mice had osteosclerosis with increased bone mineralization even though juveniles had delayed ossification. This phenotype was partially normalized by transient T3 treatment of juveniles and fully reversed in compound TRalpha1(+/m)beta(-/-) mutant mice due to 10-fold elevated hormone levels that allow the mutant TRalpha1 to bind T3. By contrast, deletion of TRbeta in TRalpha1(+/+)beta(-/ -) mice, which causes a 3-fold increase of hormone levels, led to osteoporosis in adults but advanced ossification in juveniles. T3-target gene analysis revealed skeletal hypothyroidism in TRalpha1(m/+)beta(+/-) mice, thyrotoxicosis in TRalpha1(+/+)beta(-/-) mice, and euthyroidism in TRalpha1(+/)beta(-/-) double mutants. Thus, TRalpha1 regulates both skeletal development and adult bone maintenance, with euthyroid status during development being essential to establish normal adult bone structure and mineralization.
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Affiliation(s)
- J H Duncan Bassett
- Molecular Endocrinology Group, MRC Clinical Sciences Center, Hammersmith Hospital, London W12 0NN, United Kingdom
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64
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Inherited tertiary hypothyroidism in Sprague–Dawley rats. Brain Res 2007; 1148:205-16. [DOI: 10.1016/j.brainres.2007.02.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 02/07/2007] [Accepted: 02/09/2007] [Indexed: 11/18/2022]
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Ebert R, Schütze N, Schilling T, Seefried L, Weber M, Nöth U, Eulert J, Jakob F. Influence of hormones on osteogenic differentiation processes of mesenchymal stem cells. Expert Rev Endocrinol Metab 2007; 2:59-78. [PMID: 30743749 DOI: 10.1586/17446651.2.1.59] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bone development, regeneration and maintenance are governed by osteogenic differentiation processes from mesenchymal stem cells through to mature bone cells, which are directed by local growth and differentiation factors and modulated strongly by hormones. Mesenchymal stem cells develop from both mesoderm and neural crest and can give rise to development, regeneration and maintenance of mesenchymal tissues, such as bone, cartilage, muscle, tendons and discs. There are only limited data regarding the effects of hormones on early events, such as regulation of stemness and maintenance of the mesenchymal stem cell pool. Hormones, such as estrogens, vitamin D-hormone and parathyroid hormone, besides others, are important modulators of osteogenic differentiation processes and bone formation, starting off with fate decision and the development of osteogenic offspring from mesenchymal stem cells, which end up in osteoblasts and osteocytes. Hormones are involved in fetal bone development and regeneration and, in childhood, adolescence and adulthood, they control adaptive needs for growth and reproduction, nutrition, physical power and crisis adaptation. As in other tissues, aging in mesenchymal stem cells and their osteogenic offspring is accompanied by the accumulation of genomic and proteomic damage caused by oxidative burden and insufficient repair. Failsafe programs, such as apoptosis and cellular senescence avoid tumorigenesis. Hormones can influence the pace of such events, thus supporting the quality of tissue regeneration in aging organisms in vivo; for example, by delaying osteoporosis development. The potential for hormones in systemic therapeutic strategies is well appreciated and some concepts are approved for clinical use already. Their potential for cell-based therapeutic strategies for tissue regeneration is probably underestimated and could enhance the quality of tissue-engineering constructs for transplantation and the concept of in situ-guided tissue regeneration.
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Affiliation(s)
- Regina Ebert
- a University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Norbert Schütze
- b University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Tatjana Schilling
- c University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Lothar Seefried
- d University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Meike Weber
- e University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Ulrich Nöth
- f University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Jochen Eulert
- g University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Franz Jakob
- h University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
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Fetoui H, Mahjoubi-Samet A, Jammousi K, Ellouze F, Guermazi F, Zeghal N. Energy restriction in pregnant and lactating rats lowers bone mass of their progeny. Nutr Res 2006. [DOI: 10.1016/j.nutres.2006.06.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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O'Shea PJ, Bassett JHD, Sriskantharajah S, Ying H, Cheng SY, Williams GR. Contrasting Skeletal Phenotypes in Mice with an Identical Mutation Targeted to Thyroid Hormone Receptor α1 or β. Mol Endocrinol 2005; 19:3045-59. [PMID: 16051666 DOI: 10.1210/me.2005-0224] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Thyroid hormone (T(3)) regulates bone turnover and mineralization in adults and is essential for skeletal development. Surprisingly, we identified a phenotype of skeletal thyrotoxicosis in T(3) receptor beta(PV) (TRbeta(PV)) mice in which a targeted frameshift mutation in TRbeta results in resistance to thyroid hormone. To characterize mechanisms underlying thyroid hormone action in bone, we analyzed skeletal development in TRalpha1(PV) mice in which the same PV mutation was targeted to TRalpha1. In contrast to TRbeta(PV) mice, TRalpha1(PV) mutants exhibited skeletal hypothyroidism with delayed endochondral and intramembranous ossification, severe postnatal growth retardation, diminished trabecular bone mineralization, reduced cortical bone deposition, and delayed closure of the skull sutures. Skeletal hypothyroidism in TRalpha1(PV) mutants was accompanied by impaired GH receptor and IGF-I receptor expression and signaling in the growth plate, whereas GH receptor and IGF-I receptor expression and signaling were increased in TRbeta(PV) mice. These data indicate that GH receptor and IGF-I receptor are physiological targets for T(3) action in bone in vivo. The divergent phenotypes observed in TRalpha1(PV) and TRbeta(PV) mice arise because the pituitary gland is a TRbeta-responsive tissue, whereas bone is TRalpha responsive. These studies provide a new understanding of the complex relationship between central and peripheral thyroid status.
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Affiliation(s)
- Patrick J O'Shea
- Molecular Endocrinology Group, 5th Floor Clinical Research Building, Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, Du Cane Road, London W12 0NN, United Kingdom
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Kindblom JM, Gevers EF, Skrtic SM, Lindberg MK, Göthe S, Törnell J, Vennström B, Ohlsson C. Increased adipogenesis in bone marrow but decreased bone mineral density in mice devoid of thyroid hormone receptors. Bone 2005; 36:607-16. [PMID: 15780976 DOI: 10.1016/j.bone.2005.01.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 12/06/2004] [Accepted: 01/11/2005] [Indexed: 01/02/2023]
Abstract
Mice deficient for all known thyroid hormone receptors, TRalpha1-/-beta-/- mice, display a clear skeletal phenotype characterized by growth retardation, delayed maturation of long bones and decreased trabecular and total bone mineral density (BMD; -14.6 +/- 2.8%, -14.4 +/- 1.5%). The aim of the present study was to investigate the molecular mechanisms behind the skeletal phenotype in TRalpha1-/-beta-/- mice. Global gene expression analysis was performed on total vertebrae from wild-type (WT) and TRalpha1-/-beta-/- mice using DNA microarray and the results were verified by real-time PCR. The mRNA levels of six genes (AdipoQ, Adipsin, Fat-Specific Protein 27 (FSP 27), lipoprotein lipase (LPL), retinol-binding protein (RBP) and phosphoenolpyruvate carboxykinase (PEPCK)) expressed by mature adipocytes were increased in TRalpha1-/-beta-/- compared with WT mice. An increased amount of fat (225% over WT) due to an increased number but unchanged mean size of adipocytes in the bone marrow of TRalpha1-/-beta-/- mice was revealed. Interestingly, the mRNA levels of the key regulator of osteoclastogenesis, receptor activator of NF-varkappab ligand (RANKL), were dramatically decreased in TRalpha1-/-beta-/- mice. In conclusion, TRalpha1-/-beta-/- mice demonstrated increased expression of adipocyte specific genes and an increased amount of bone marrow fat. Thus, these mice have increased adipogenesis in bone marrow associated with decreased trabecular bone mineral density (BMD). One may speculate that these effects either could be caused by an imbalance in the differentiation of the osteoblast and the adipocyte lineages at the expense of osteoblastogenesis, or by independent effects on the regulation of both osteoblastogenesis and adipogenesis.
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Affiliation(s)
- Jenny M Kindblom
- Center for Bone Research at the Sahlgrenska Academy, RCEM, Department of Internal Medicine, The Sahlgrenska Academy at Gothenburg University, Sweden.
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69
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Morimura T, Tsunekawa K, Kasahara T, Seki K, Ogiwara T, Mori M, Murakami M. Expression of type 2 iodothyronine deiodinase in human osteoblast is stimulated by thyrotropin. Endocrinology 2005; 146:2077-84. [PMID: 15650076 DOI: 10.1210/en.2004-1432] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Thyroid hormones play important roles in bone growth, development, and turnover. To exert its biological activity, T(4) needs to be converted to T(3) by iodothyronine deiodinase. In human thyroid gland as well as rat brown adipose tissue, type 2 iodothyronine deiodinase (D2) expression is regulated by a TSH receptor-cAMP-mediated mechanism. TSH receptor knockout mice demonstrated the direct effects of TSH on bone via TSH receptors found on osteoblast and osteoclast precursors. In the present study we investigated the possible expression and function of iodothyronine deiodinase and TSH receptors in human osteoblast-like osteosarcoma (SaOS-2) cells and normal human osteoblast (NHOst) cells. Iodothyronine deiodinase activity was detected in SaOS-2 cells and NHOst cells, and all of the characteristics of deiodinating activity were compatible with those of D2. Northern analysis demonstrated D2 mRNA expression in SaOS-2 cells and NHOst cells. D2 mRNA levels as well as D2 activities were rapidly increased by dibutyryl cAMP or forskolin in SaOS-2 cells and NHOst cells. TSH receptor mRNA was demonstrated in SaOS-2 cells and NHOst cells, and D2 mRNA and D2 activity were stimulated by TSH in both cells. In addition, all T(3) receptor isoforms were detected by RT-PCR in SaOS-2 cells and NHOst cells. The present results indicate the expression of functional TSH receptors and D2 in human osteoblasts and suggest previously unrecognized roles of TSH receptors and local T(3) production by D2 in the pathophysiology of human osteoblasts.
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Affiliation(s)
- Tadashi Morimura
- Department of Clinical Laboratory Medicine, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
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70
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Angelin-Duclos C, Domenget C, Kolbus A, Beug H, Jurdic P, Samarut J. Thyroid hormone T3 acting through the thyroid hormone α receptor is necessary for implementation of erythropoiesis in the neonatal spleen environment in the mouse. Development 2005; 132:925-34. [PMID: 15673575 DOI: 10.1242/dev.01648] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Thyroid hormones (THs) mediate many physiological and developmental functions in vertebrates. All these functions are mediated by binding of the active form of the TH T3 to the specific nuclear receptors TRα and TRβ, which are transcription factors. Using mutant mice lacking TRs or deficient for TH production, we show that T3 influences neonatal erythropoiesis through TRα. The effect of T3 and TRα is restricted to this developmental window and is specific for the spleen but not for other erythropoietic organs. We show that T3 via TRα affects late steps of erythrocytic development, promoting the proliferation of late basophilic erythroblasts. In vitro, this effect is exerted directly on erythrocytic cells. In vivo, the action of T3 is also intrinsic to spleen erythrocytic progenitors, as shown by grafting experiments of splenocytes derived from wildtype and TRα knockout (TRα0/0) mice into wild-type and TRα0/0 irradiated recipients. Our results indicate that defective spleen erythropoiesis in hypothyroid and TRα0/0mice results from impaired recognition of the spleen environment by the mutant erythrocytic progenitors. The data presented support a model in which T3 signaling through TRα is essential for the implementation of the transient spleen erythropoiesis at birth.
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Affiliation(s)
- Cristina Angelin-Duclos
- Ecole Normale Supérieure de Lyon, UMR CNRS 5161, INRA 1237, IFR128 Biosciences Lyon-Gerland, 46 Allée d'Italie, 69364 Lyon Cedex 07, France
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71
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Freitas FRS, Capelo LP, O'Shea PJ, Jorgetti V, Moriscot AS, Scanlan TS, Williams GR, Zorn TMT, Gouveia CHA. The thyroid hormone receptor beta-specific agonist GC-1 selectively affects the bone development of hypothyroid rats. J Bone Miner Res 2005; 20:294-304. [PMID: 15647824 DOI: 10.1359/jbmr.041116] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Revised: 08/16/2004] [Accepted: 09/14/2004] [Indexed: 12/14/2022]
Abstract
UNLABELLED We investigated the effects of GC-1, a TRbeta-selective thyromimetic, on bone development of hypothyroid rats. Whereas T3 reverted the IGF-I deficiency and the skeletal defects caused by hypothyroidism, GC-1 had no effect on serum IGF-I or on IGF-I protein expression in the epiphyseal growth plate of the femur, but induced selective effects on bone development. Our findings indicate that T3 exerts some essential effects on bone development that are mediated by TRbeta1. INTRODUCTION We investigated the role of the thyroid hormone receptor beta1 (TRbeta1) on skeletal development of rats using the TRbeta-selective agonist GC-1. MATERIALS AND METHODS Twenty-one-day-old female rats (n = 6/group) were rendered hypothyroid (Hypo) and treated for 5 weeks with 0.3 ug/100 g BW/day of T3 (1xT3), 5xT3, or equimolar doses of GC-1 (1xGC-1 and 5xGC-1). Serum triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), and insulin-like growth factor (IGF)-I concentrations were determined by radioimmunoassay (RIA). BMD and longitudinal bone growth were determined by DXA. Trabecular bone histomorphometry and epiphyseal growth plate (EGP) morphometry were performed in the distal femur. Expressions of IGF-I protein and of collagen II and X mRNA were evaluated by immunohistochemistry and in situ hybridization, respectively. To determine hormonal effects on ossification, skeletal preparations of hypothyroid-, 5xGC-1-, and 5xT3-treated neonatal rats were compared. RESULTS Hypothyroidism impaired longitudinal body growth and BMD gain, delayed ossification, reduced the number of hypertrophic chondrocytes (HCs; 72% versus Euthyroid [Eut] rats; p < 0.001), and resulted in disorganized columns of EGP chondrocytes. Serum IGF-I was 67% reduced versus Eut rats (p < 0.001), and the expression of IGF-I protein and collagen II and X mRNA were undetectable in the EGP of Hypo rats. T3 completely or partially normalized all these parameters. In contrast, GC-1 did not influence serum concentrations or EGP expression of IGF-I, failed to reverse the disorganization of proliferating chondrocyte columns, and barely affected longitudinal growth. Nevertheless, GC-1 induced ossification, HC differentiation, and collagen II and X mRNA expression and increased EGP thickness to Eut values. GC-1-treated rats had higher BMD gain in the total tibia, total femur, and in the femoral diaphysis than Hypo animals (p < 0.05). These changes were associated with increased trabecular volume (48%, p < 0.01), mineralization apposition rate (2.3-fold, p < 0.05), mineralizing surface (4.3-fold, p < 0.01), and bone formation rate (10-fold, p < 0.01). CONCLUSIONS Treatment of hypothyroid rats with the TRbeta-specific agonist GC-1 partially reverts the skeletal development and maturation defects resultant of hypothyroidism. This finding suggests that TRbeta1 has an important role in bone development.
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Affiliation(s)
- Fatima R S Freitas
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
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72
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Affiliation(s)
- Elaine Murphy
- Molecular Endocrinology Group, 5th Floor MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, London, UK
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73
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Shen S, Berry W, Jaques S, Pillai S, Zhu J. Differential expression of iodothyronine deiodinase type 2 in growth plates of chickens divergently selected for incidence of tibial dyschondroplasia. Anim Genet 2004; 35:114-8. [PMID: 15025570 DOI: 10.1111/j.1365-2052.2004.01103.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tibial dyschondroplasia (TD) is a genetic leg defect in broilers with a lesion of avascular, non-calcified cartilage below the growth plate of the proximal tibiatarsus. This disease is considered to result from the inability of chondrocytes to undergo terminal differentiation. Thyroid hormones are required for chondrocyte differentiation. The thyroid gland produces and secrets mostly L-thyroxine or T4 and T4 plays most of its biological activities through conversion to triiodothyronine or T3 in local tissues by iodothyronine deiodinases type 1 or type 2, which are tissue specific. In this study, no differences were found in the plasma concentrations of total T3 and T4 between two chicken lines divergently selected for the incidence of TD. Plasma T4 was higher than T3, especially in older chickens. Younger birds had much higher T3 than older birds, but there were no significant age differences in T4. The expression level of deiodinase type 2 in the growth plates of broilers with TD was one-eighth of those birds without the disease. The expression levels of deiodinase type 2 (DIO2) in commercial broilers without the disease were much higher than those with TD and lower than those without the disease in the susceptible and resistant lines, respectively. These results indicate that the inadequate expression of DIO2 in the growth plates contributes to the pathogenesis of TD in broilers and that TD is a tissue-specific hypothyroidism.
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Affiliation(s)
- S Shen
- Department of Poultry Science, Texas A&M University, College Station, TX 77843, USA
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74
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75
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Harvey CB, Stevens DA, Williams AJ, Jackson DJ, O'Shea P, Williams GR. Analysis of thyroid hormone responsive gene expression in osteoblastic cells. Mol Cell Endocrinol 2003; 213:87-97. [PMID: 15062577 DOI: 10.1016/j.mce.2003.10.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Thyroid hormones regulate gene expression to influence the development and metabolism of many tissues including bone. The identification of genes that are regulated by thyroid hormones during skeletal development requires sensitive and quantitative techniques that are not limited by small amounts of available tissue and RNA. We have compared the efficiencies of differential display and poly A PCR subtraction hybridisation methods for the detection of thyroid hormone responsive genes expressed in osteoblastic cells. The utility of each technique was evaluated with respect to its sensitivity, specificity, cost and ability to identify novel genes. Subtraction hybridisation was rapid and more efficient in all categories. Poly A PCR facilitates quantitative and representative global amplification of cDNAs from low concentrations of RNA extracted from small tissue samples. The method, in combination with microarray analyses, may prove useful as an additional, complementary strategy to subtraction hybridisation for the analysis of differential gene expression in tissues where sample size is limiting.
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Affiliation(s)
- C B Harvey
- Division of Medicine and MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
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76
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O'Shea PJ, Harvey CB, Suzuki H, Kaneshige M, Kaneshige K, Cheng SY, Williams GR. A thyrotoxic skeletal phenotype of advanced bone formation in mice with resistance to thyroid hormone. Mol Endocrinol 2003; 17:1410-24. [PMID: 12677005 DOI: 10.1210/me.2002-0296] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Thyroid hormone (T3) regulates bone turnover and mineralization in adults and is essential for skeletal development during childhood. Hyperthyroidism is an established risk factor for osteoporosis. Nevertheless, T3 actions in bone remain poorly understood. Patients with resistance to thyroid hormone, due to mutations of the T3-receptor beta (TRbeta) gene, display variable phenotypic abnormalities, particularly in the skeleton. To investigate the actions of T3 during bone development, we characterized the skeleton in TRbetaPV mutant mice. TRbetaPV mice harbor a targeted resistance to thyroid hormone mutation in TRbeta and recapitulate the human condition. A severe phenotype, which includes shortened body length, was evident in homozygous TRbetaPV/PV animals. Accelerated growth in utero was associated with advanced endochondral and intramembranous ossification. Advanced bone formation resulted in postnatal growth retardation, premature quiescence of the growth plates, and shortened bone length, together with increased bone mineralization and craniosynostosis. In situ hybridization demonstrated increased expression of fibroblast growth factor receptor-1, a T3-regulated gene in bone, in TRbetaPV/PV perichondrium, growth plate chondrocytes, and osteoblasts. Thus, the skeleton in TRbetaPV/PV mice is thyrotoxic and displays phenotypic features typical of juvenile hyperthyroidism.
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MESH Headings
- Animals
- Animals, Newborn
- Body Height/genetics
- Bone Density
- Bone Development/genetics
- Bone and Bones/abnormalities
- Craniosynostoses/genetics
- Craniosynostoses/pathology
- Female
- Gene Expression Regulation, Developmental
- Growth Plate
- Hyperthyroidism/genetics
- Limb Deformities, Congenital/genetics
- Limb Deformities, Congenital/pathology
- Male
- Mice
- Mice, Mutant Strains
- Receptor Protein-Tyrosine Kinases/genetics
- Receptor, Fibroblast Growth Factor, Type 1
- Receptors, Fibroblast Growth Factor/genetics
- Receptors, Thyroid Hormone/genetics
- Receptors, Thyroid Hormone/metabolism
- Thyroid Hormone Receptors beta
- Thyroid Hormone Resistance Syndrome/genetics
- Thyroid Hormone Resistance Syndrome/physiopathology
- Thyroxine/blood
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Affiliation(s)
- Patrick J O'Shea
- Molecular Endocrinology Group, Division of Medicine and Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, United Kingdom
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77
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Abstract
The genes encoding thyroid hormone receptor alpha and beta (TRalpha and TRbeta) encode four thyroid hormone receptors and four variant isoforms with antagonistic properties. Because of this complexity, numerous models of TR mutation have been developed to understand the functions of specific receptors. In total, 13 mutant strains are now available. Phenotype analysis has shown that the two genes serve distinct functions: TRalpha is crucial for postnatal development and cardiac function, whereas TRbeta mainly controls inner ear and retina development, liver metabolism and thyroid hormone levels. These mouse mutant strains also provide us with the unique opportunity to address the respective contribution of each receptor isoform and isotype in vivo and highlight the in vivo importance of the ligand-independent function of the TR gene products.
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Affiliation(s)
- Frédéric Flamant
- Laboratoire de Biologie Moléculaire et Cellulaire de l'Ecole Normale Supérieure de Lyon UMR CNRS 5665 LA INRA 913, 46 Allée d'Italie 69364 Lyon CEDEX07, France.
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