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Zsarnovszky A, Kiss D, Jocsak G, Nemeth G, Toth I, Horvath TL. Thyroid hormone- and estrogen receptor interactions with natural ligands and endocrine disruptors in the cerebellum. Front Neuroendocrinol 2018; 48:23-36. [PMID: 28987779 DOI: 10.1016/j.yfrne.2017.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 09/06/2017] [Accepted: 10/04/2017] [Indexed: 10/18/2022]
Abstract
Although the effects of phytoestrogens on brain function is widely unknown, they are often regarded as "natural" and thus as harmless. However, the effects of phytoestrogens or environmental pollutants on brain function is underestimated. Estrogen (17beta-estradiol, E2) and thyroid hormones (THs) play pivotal roles in brain development. In the mature brain, these hormones regulate metabolism on cellular and organismal levels. Thus, E2 and THs do not only regulate the energy metabolism of the entire organism, but simultaneously also regulate important homeostatic parameters of neurons and glia in the CNS. It is, therefore, obvious that the mechanisms through which these hormones exert their effects are pleiotropic and include both intra- and intercellular actions. These hormonal mechanisms are versatile, and the experimental investigation of simultaneous hormone-induced mechanisms is technically challenging. In addition, the normal physiological settings of metabolic parameters depend on a plethora of interactions of the steroid hormones. In this review, we discuss conceptual and experimental aspects of the gonadal and thyroid hormones as they relate to in vitro models of the cerebellum.
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Affiliation(s)
- Attila Zsarnovszky
- Department of Animal Physiology and Animal Health, Faculty of Agricultural and Environmental Sciences, Szent István University, Páter Károly u. 1, H-2100 Gödöllő, Hungary; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA.
| | - David Kiss
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Gergely Jocsak
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Gabor Nemeth
- Department of Obstetrics and Gynecology, University of Szeged, School of Medicine, Szeged, Hungary
| | - Istvan Toth
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Tamas L Horvath
- Department of Animal Physiology and Animal Health, Faculty of Agricultural and Environmental Sciences, Szent István University, Páter Károly u. 1, H-2100 Gödöllő, Hungary; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA; Departments of Anatomy and Histology, University of Veterinary Medicine, Budapest 1078, Hungary.
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52
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Landers K, Richard K. Traversing barriers - How thyroid hormones pass placental, blood-brain and blood-cerebrospinal fluid barriers. Mol Cell Endocrinol 2017; 458:22-28. [PMID: 28153799 DOI: 10.1016/j.mce.2017.01.041] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/19/2017] [Accepted: 01/24/2017] [Indexed: 11/21/2022]
Abstract
Thyroid hormone is essential for normal human fetal growth and brain development. As the fetal thyroid does not secrete thyroid hormones until about 18 weeks gestation, early fetal brain development depends on passage of maternal hormone across the placenta into the fetal circulation. To reach the fetal brain, maternally derived and endogenously produced thyroid hormone has to cross the blood-brain and blood-cerebrospinal fluid barriers. In this review we will discuss the complex biological barriers (involving membrane transporters, enzymes and distributor proteins) that must be overcome to ensure that the developing human brain has adequate exposure to thyroid hormone.
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Affiliation(s)
- Kelly Landers
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, Qld 4029, Australia
| | - Kerry Richard
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, Qld 4029, Australia; School of Medicine, University of Queensland, Herston, Qld 4029, Australia; School of Biomedical Sciences, Queensland University of Technology, Brisbane, Qld 4000, Australia.
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53
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Zhang B, Cui Y, Wang L, Zhao L, Hou C, Zeng Q, Zhang Z, Yu J, Zhao Y, Nie J, Chen X, Wang A, Liu H. Autophagy regulates high concentrations of iodide-induced apoptosis in SH-SY5Y cells. Toxicol Lett 2017; 284:129-135. [PMID: 29241733 DOI: 10.1016/j.toxlet.2017.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 12/07/2017] [Accepted: 12/09/2017] [Indexed: 01/23/2023]
Abstract
To date, there are many people residing in areas with high levels of iodide in water. Our previous epidemiological study showed that exposure to high iodine in drinking water significantly reduced the intelligence of children although the mechanisms remain unclear. To explore whether high concentrations of iodide may cause cytotoxic effect and the role of autophagy in the high iodide-induced apoptosis, human neuroblastoma cells (SH-SY5Y cells) were exposed to high concentrations of iodide. Morphological phenotypes, cell viability, Hoechst 33258 staining, the expression levels of apoptosis and autophagy-related proteins were detected. A possible effect of an inhibitor (3-methyladenine, 3-MA) or an inducer (rapamycin) of autophagy on high iodide-induced apoptosis also was examined. Results indicated that high iodide changed cellular morphology, decreased cell viability and increased the protein's expression level of apoptosis and autophagy. In addition, high iodide-induced apoptosis was enhanced by inhibition of autophagy and inhibited by activation of autophagy in SH-SY5Y cells. Collectively, high concentrations of iodide are toxic to SH-SY5Y cells, as well as induce apoptosis and autophagy. Furthermore, autophagy plays a regulatory role in high concentrations of iodide-induced apoptosis in SH-SY5Y cells.
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Affiliation(s)
- Bin Zhang
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China
| | - Yushan Cui
- Tianjin Centers for Disease Control and Prevention, 6 Huayue Road, Hedong District, Tianjin 300011, People's Republic of China
| | - Lingzhi Wang
- Department of Quality Control, The First Affiliated Hospital of Zhejiang University, School of Medcine, Hangzhou, Zhejiang, People's Republic of China
| | - Liang Zhao
- Tianjin Centers for Disease Control and Prevention, 6 Huayue Road, Hedong District, Tianjin 300011, People's Republic of China
| | - Changchun Hou
- Tianjin Centers for Disease Control and Prevention, 6 Huayue Road, Hedong District, Tianjin 300011, People's Republic of China
| | - Qiang Zeng
- Tianjin Centers for Disease Control and Prevention, 6 Huayue Road, Hedong District, Tianjin 300011, People's Republic of China
| | - Zushan Zhang
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China
| | - Jingwen Yu
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China
| | - Yang Zhao
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China
| | - Junyan Nie
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China
| | - Xuemin Chen
- Department of Environmental Health and MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Hubei, Wuhan 430030, People's Republic of China
| | - Aiguo Wang
- Department of Environmental Health and MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Hubei, Wuhan 430030, People's Republic of China.
| | - Hongliang Liu
- School of Public Health, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, People's Republic of China; Tianjin Centers for Disease Control and Prevention, 6 Huayue Road, Hedong District, Tianjin 300011, People's Republic of China; Tianjin Municipal Inspection Bureau for Health And Family Planning, 94 Guizhou Road, Heping District, Tianjin 300070, People's Republic of China.
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54
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Silva N, Louro B, Trindade M, Power DM, Campinho MA. Transcriptomics reveal an integrative role for maternal thyroid hormones during zebrafish embryogenesis. Sci Rep 2017; 7:16657. [PMID: 29192226 PMCID: PMC5709499 DOI: 10.1038/s41598-017-16951-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 11/20/2017] [Indexed: 02/06/2023] Open
Abstract
Thyroid hormones (THs) are essential for embryonic brain development but the genetic mechanisms involved in the action of maternal THs (MTHs) are still largely unknown. As the basis for understanding the underlying genetic mechanisms of MTHs regulation we used an established zebrafish monocarboxylic acid transporter 8 (MCT8) knock-down model and characterised the transcriptome in 25hpf zebrafish embryos. Subsequent mapping of differentially expressed genes using Reactome pathway analysis together with in situ expression analysis and immunohistochemistry revealed the genetic networks and cells under MTHs regulation during zebrafish embryogenesis. We found 4,343 differentially expressed genes and the Reactome pathway analysis revealed that TH is involved in 1681 of these pathways. MTHs regulated the expression of core developmental pathways, such as NOTCH and WNT in a cell specific context. The cellular distribution of neural MTH-target genes demonstrated their cell specific action on neural stem cells and differentiated neuron classes. Taken together our data show that MTHs have a role in zebrafish neurogenesis and suggest they may be involved in cross talk between key pathways in neural development. Given that the observed MCT8 zebrafish knockdown phenotype resembles the symptoms in human patients with Allan-Herndon-Dudley syndrome our data open a window into understanding the genetics of this human congenital condition.
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Affiliation(s)
- Nadia Silva
- Comparative Endocrinology and Integrative Biology Group, Centre for Marine Sciences (CCMAR), Universidade do Algarve, Faro, Portugal
| | - Bruno Louro
- Comparative Endocrinology and Integrative Biology Group, Centre for Marine Sciences (CCMAR), Universidade do Algarve, Faro, Portugal
| | - Marlene Trindade
- Comparative Endocrinology and Integrative Biology Group, Centre for Marine Sciences (CCMAR), Universidade do Algarve, Faro, Portugal
| | - Deborah M Power
- Comparative Endocrinology and Integrative Biology Group, Centre for Marine Sciences (CCMAR), Universidade do Algarve, Faro, Portugal
| | - Marco A Campinho
- Comparative Endocrinology and Integrative Biology Group, Centre for Marine Sciences (CCMAR), Universidade do Algarve, Faro, Portugal.
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Xiong J, Tian L, Qiu Y, Sun D, Zhang H, Wu M, Wang J. Evaluation on the thyroid disrupting mechanism of malathion in Fischer rat thyroid follicular cell line FRTL-5. Drug Chem Toxicol 2017; 41:501-508. [PMID: 29143548 DOI: 10.1080/01480545.2017.1397162] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Thyroid hormones are involved in many important physiological activities including regulation of energy metabolism, development of nervous system, maintenance of cerebral functions, and so on. Endocrine-disrupting chemicals (EDCs) that interfere with thyroid functions raise serious concerns due to their frequent misuse in areas where regulations are poorly implemented. In addition, chemicals that are originally regarded safe may now be considered as toxic with the development of life sciences. Malathion is an organophosphate insecticide that is widely applied and distributed in agricultural and residential settings. Due to the low acute toxicity and rapid degradation, malathion is not listed as a primary thyroid disrupting chemical. However, emerging evidences reported that malathion affected thyroperoxidase catalyzed iodide oxidation which in turn influenced thyroid hormone transportation, and enhanced parathyroid hyperplasia prevalence. Nevertheless, direct effect of malathion on thyroid hormone biosynthesis remains to be elucidated. This study investigated the effects of thyroid disruption of malathion in Fischer rat thyroid follicular cell line, FRTL-5. Transcriptional and translational analyses on thyroglobulin demonstrated that both mRNA and protein expression levels were significantly inhibited by malathion. Cellular cAMP level and TSH receptor expression were distinctly reduced by malathion (6.0 µg/ml). These results suggested that malathion directly disrupted the biosynthesis of thyroid hormone and the mechanism involved down-regulation of TSH receptor and cellular cAMP. This subsequently led to the suppression of TSH dependent signal transduction, TG transcription inhibition, and obstruction of thyroid hormone biosynthesis.
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Affiliation(s)
- Jingyuan Xiong
- a Research Center for Public Health and Preventive Medicine , West China School of Public Health, Sichuan University , Chengdu , China
| | - Liantian Tian
- b West China Teaching Hospital, Sichuan University , Chengdu , China
| | - Yongjie Qiu
- c Department of Environmental and Occupational Medicine , West China School of Public Health, Sichuan University , Chengdu , China
| | - Ding Sun
- d School of Humanities and Information Management , Chengdu Medical College , Chengdu , China
| | - Hao Zhang
- c Department of Environmental and Occupational Medicine , West China School of Public Health, Sichuan University , Chengdu , China
| | - Mei Wu
- c Department of Environmental and Occupational Medicine , West China School of Public Health, Sichuan University , Chengdu , China
| | - Jintao Wang
- c Department of Environmental and Occupational Medicine , West China School of Public Health, Sichuan University , Chengdu , China
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56
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Anttonen AK, Laari A, Kousi M, Yang YJ, Jääskeläinen T, Somer M, Siintola E, Jakkula E, Muona M, Tegelberg S, Lönnqvist T, Pihko H, Valanne L, Paetau A, Lun MP, Hästbacka J, Kopra O, Joensuu T, Katsanis N, Lehtinen MK, Palvimo JJ, Lehesjoki AE. ZNHIT3 is defective in PEHO syndrome, a severe encephalopathy with cerebellar granule neuron loss. Brain 2017; 140:1267-1279. [PMID: 28335020 DOI: 10.1093/brain/awx040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 01/06/2017] [Indexed: 11/12/2022] Open
Abstract
Progressive encephalopathy with oedema, hypsarrhythmia, and optic atrophy (PEHO) syndrome is an early childhood onset, severe autosomal recessive encephalopathy characterized by extreme cerebellar atrophy due to almost total granule neuron loss. By combining homozygosity mapping in Finnish families with Sanger sequencing of positional candidate genes and with exome sequencing a homozygous missense substitution of leucine for serine at codon 31 in ZNHIT3 was identified as the primary cause of PEHO syndrome. ZNHIT3 encodes a nuclear zinc finger protein previously implicated in transcriptional regulation and in small nucleolar ribonucleoprotein particle assembly and thus possibly to pre-ribosomal RNA processing. The identified mutation affects a highly conserved amino acid residue in the zinc finger domain of ZNHIT3. Both knockdown and genome editing of znhit3 in zebrafish embryos recapitulate the patients' cerebellar defects, microcephaly and oedema. These phenotypes are rescued by wild-type, but not mutant human ZNHIT3 mRNA, suggesting that the patient missense substitution causes disease through a loss-of-function mechanism. Transfection of cell lines with ZNHIT3 expression vectors showed that the PEHO syndrome mutant protein is unstable. Immunohistochemical analysis of mouse cerebellar tissue demonstrated ZNHIT3 to be expressed in proliferating granule cell precursors, in proliferating and post-mitotic granule cells, and in Purkinje cells. Knockdown of Znhit3 in cultured mouse granule neurons and ex vivo cerebellar slices indicate that ZNHIT3 is indispensable for granule neuron survival and migration, consistent with the zebrafish findings and patient neuropathology. These results suggest that loss-of-function of a nuclear regulator protein underlies PEHO syndrome and imply that establishment of its spatiotemporal interaction targets will be the basis for developing therapeutic approaches and for improved understanding of cerebellar development.
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Affiliation(s)
- Anna-Kaisa Anttonen
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland.,Medical and Clinical Genetics, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Anni Laari
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Maria Kousi
- Center for Human Disease Modeling, Duke University Medical Center, Carmichael Building, 300 North Duke Street, Suite 48-118, Durham, NC 27701, USA
| | - Yawei J Yang
- Division of Genetics, Howard Hughes Medical Institute.,Institute for Molecular Medicine Finland, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland.,Department of Pediatric Neurology, Children's Hospital, University of Helsinki and Helsinki University Hospital, Lastenlinnantie 2, 00290 Helsinki, Finland
| | - Tiina Jääskeläinen
- Institute of Biomedicine, University of Eastern Finland, Yliopistonranta 1, 70210 Kuopio, Finland.,Institute of Dentistry, University of Eastern Finland, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Mirja Somer
- The Norio Centre, The Rinnekoti Foundation, Kornetintie 8, 00380 Helsinki, Finland
| | - Eija Siintola
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland
| | - Eveliina Jakkula
- Institute for Molecular Medicine Finland, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Mikko Muona
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland.,Institute for Molecular Medicine Finland, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Saara Tegelberg
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Tuula Lönnqvist
- Department of Pediatric Neurology, Children's Hospital, University of Helsinki and Helsinki University Hospital, Lastenlinnantie 2, 00290 Helsinki, Finland
| | - Helena Pihko
- Department of Pediatric Neurology, Children's Hospital, University of Helsinki and Helsinki University Hospital, Lastenlinnantie 2, 00290 Helsinki, Finland
| | - Leena Valanne
- Department of Radiology, HUS Medical Imaging Center, Haartmaninkatu 4, 00290 Helsinki, Finland
| | - Anders Paetau
- Department of Pathology, Helsinki University Hospital, Haartmaninkatu 3, 00290 Helsinki, Finland
| | - Melody P Lun
- Department of Pathology, Boston Children's Hospital, BCH 3108, 300 Longwood Ave., Boston, MA 02115, USA.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, 670 Albany Street, Boston, MA 02118, USA
| | - Johanna Hästbacka
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Department of Pediatrics, Children's Hospital, University of Helsinki and Helsinki University Hospital, Stenbäckinkatu 11, 00290 Helsinki, Finland
| | - Outi Kopra
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Tarja Joensuu
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University Medical Center, Carmichael Building, 300 North Duke Street, Suite 48-118, Durham, NC 27701, USA
| | - Maria K Lehtinen
- Department of Pathology, Boston Children's Hospital, BCH 3108, 300 Longwood Ave., Boston, MA 02115, USA
| | - Jorma J Palvimo
- Institute of Biomedicine, University of Eastern Finland, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Anna-Elina Lehesjoki
- The Folkhälsan Institute of Genetics, Haartmaninkatu 8, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, Viikinkaari 4, 00790 Helsinki, Finland.,Research Programs Unit, Molecular Neurology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
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57
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Chen C, Ma Q, Deng P, Yang J, Yang L, Lin M, Yu Z, Zhou Z. Critical role of TRPC1 in thyroid hormone-dependent dopaminergic neuron development. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1900-1912. [PMID: 28779972 DOI: 10.1016/j.bbamcr.2017.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 07/21/2017] [Accepted: 07/31/2017] [Indexed: 01/20/2023]
Abstract
Thyroid hormones play a crucial role in midbrain dopaminergic (DA) neuron development. However, the underlying molecular mechanisms remain largely unknown. In this study, we revealed that thyroid hormone treatment evokes significant calcium entry through canonical transient receptor potential (TRPC) channels in ventral midbrain neural stem cells and this calcium signaling is essential for thyroid hormone-dependent DA neuronal differentiation. We also found that TRPC1 is the dominant TRPC channel expressed in ventral midbrain neural stem cells which responds to thyroid hormone. In addition, thyroid hormone increases TRPC1 expression through its receptor alpha 1 during DA neuron differentiation, and, importantly, produces calcium signals by activating TRPC1 channels. In vivo and in vitro gene silencing experiments indicate that TRPC1-mediated calcium signaling is required for thyroid hormone-dependent DA neuronal differentiation. Finally, we confirmed that the activation of OTX2, a determinant of DA neuron development and the expression of which is induced by thyroid hormone, is dependent on TRPC1-mediated calcium signaling. These data revealed the molecular mechanisms of how thyroid hormone regulates DA neuron development from ventral midbrain neural stem cells, particularly endowing a novel physiological relevance to TRPC1 channels.
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Affiliation(s)
- Chunhai Chen
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China.
| | - Qinglong Ma
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China
| | - Ping Deng
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China
| | - Jianjing Yang
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX 75390-9148, USA
| | - Lingling Yang
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China
| | - Min Lin
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China
| | - Zhengping Yu
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China
| | - Zhou Zhou
- Department of Occupational Health, Third Military Medical University, No.30 Gaotanyan Street, Chongqing 400038, China.
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58
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Strobl MTJ, Freeman D, Patel J, Poulsen R, Wendler CC, Rivkees SA, Coleman JE. Opposing Effects of Maternal Hypo- and Hyperthyroidism on the Stability of Thalamocortical Synapses in the Visual Cortex of Adult Offspring. Cereb Cortex 2017; 27:3015-3027. [PMID: 27235101 PMCID: PMC6059113 DOI: 10.1093/cercor/bhw096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Insufficient or excessive thyroid hormone (TH) levels during fetal development can cause long-term neurological and cognitive problems. Studies in animal models of perinatal hypo- and hyperthyroidism suggest that these problems may be a consequence of the formation of maladaptive circuitry in the cerebral cortex, which can persist into adulthood. Here we used mouse models of maternal hypo- and hyperthyroidism to investigate the long-term effects of altering thyroxine (T4) levels during pregnancy (corresponding to embryonic days 6.5-18.5) on thalamocortical (TC) axon dynamics in adult offspring. Because perinatal hypothyroidism has been linked to visual processing deficits in humans, we performed chronic two-photon imaging of TC axons and boutons in primary visual cortex (V1). We found that a decrease or increase in maternal serum T4 levels was associated with atypical steady-state dynamics of TC axons and boutons in V1 of adult offspring. Hypothyroid offspring exhibited axonal branch and bouton dynamics indicative of an abnormal increase in TC connectivity, whereas changes in hyperthyroid offspring were indicative of an abnormal decrease in TC connectivity. Collectively, our data suggest that alterations to prenatal T4 levels can cause long-term synaptic instability in TC circuits, which could impair early stages of visual processing.
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Affiliation(s)
- Marie-Therese J. Strobl
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
- Department of Nuclear Medicine, University Medical Center, University RWTH Aachen, 52074 Aachen, Germany
| | - Daniel Freeman
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Jenica Patel
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Ryan Poulsen
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Christopher C. Wendler
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Scott A. Rivkees
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Jason E. Coleman
- Department of Pediatrics, Child Health Research Institute,University of Florida College of Medicine, Gainesville, FL 32610, USA
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59
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Bronchain OJ, Chesneau A, Monsoro-Burq AH, Jolivet P, Paillard E, Scanlan TS, Demeneix BA, Sachs LM, Pollet N. Implication of thyroid hormone signaling in neural crest cells migration: Evidence from thyroid hormone receptor beta knockdown and NH3 antagonist studies. Mol Cell Endocrinol 2017; 439:233-246. [PMID: 27619407 DOI: 10.1016/j.mce.2016.09.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 11/18/2022]
Abstract
Thyroid hormones (TH) have been mainly associated with post-embryonic development and adult homeostasis but few studies report direct experimental evidence for TH function at very early phases of embryogenesis. We assessed the outcome of altered TH signaling on early embryogenesis using the amphibian Xenopus as a model system. Precocious exposure to the TH antagonist NH-3 or impaired thyroid receptor beta function led to severe malformations related to neurocristopathies. These include pathologies with a broad spectrum of organ dysplasias arising from defects in embryonic neural crest cell (NCC) development. We identified a specific temporal window of sensitivity that encompasses the emergence of NCCs. Although the initial steps in NCC ontogenesis appeared unaffected, their migration properties were severely compromised both in vivo and in vitro. Our data describe a role for TH signaling in NCCs migration ability and suggest severe consequences of altered TH signaling during early phases of embryonic development.
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Affiliation(s)
- Odile J Bronchain
- Paris-Saclay Institute of Neuroscience, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405, Orsay, France.
| | - Albert Chesneau
- Paris-Saclay Institute of Neuroscience, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Anne-Hélène Monsoro-Burq
- Univ Paris Sud, Université Paris Saclay, Centre Universitaire, F-91405, Orsay, France; Institut Curie PSL Research University, Centre Universitaire, F-91405, Orsay, France; UMR 3347 CNRS, U1021 Inserm, Université Paris Saclay, Centre Universitaire, F-91405, Orsay, France
| | - Pascale Jolivet
- CNRS, Sorbonne Universités, UPMC University Paris 06, UMR8226, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Institut de Biologie Physico-Chimique, 75005, Paris, France; UMR 7221 CNRS, Muséum National d'histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Sorbonne Universités, 75005, Paris, France
| | - Elodie Paillard
- Watchfrog S.A., 1 Rue Pierre Fontaine, 91000, Evry, France; Institute of Systems and Synthetic Biology, CNRS, Université d'Evry Val d'Essonne, Bâtiment 3, Genopole(®) Campus 3, 1, Rue Pierre Fontaine, F-91058, Evry, France
| | - Thomas S Scanlan
- Department of Physiology & Pharmacology, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, L334, Portland, OR, 97239-3098, USA
| | - Barbara A Demeneix
- UMR 7221 CNRS, Muséum National d'histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Sorbonne Universités, 75005, Paris, France
| | - Laurent M Sachs
- UMR 7221 CNRS, Muséum National d'histoire Naturelle, Dépt. Régulation, Développement et Diversité Moléculaire, Sorbonne Universités, 75005, Paris, France
| | - Nicolas Pollet
- Institute of Systems and Synthetic Biology, CNRS, Université d'Evry Val d'Essonne, Bâtiment 3, Genopole(®) Campus 3, 1, Rue Pierre Fontaine, F-91058, Evry, France; Evolution, Génomes, Comportement & Ecologie, CNRS, IRD, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette, France
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Salerno M, Capalbo D, Cerbone M, De Luca F. Subclinical hypothyroidism in childhood - current knowledge and open issues. Nat Rev Endocrinol 2016; 12:734-746. [PMID: 27364598 DOI: 10.1038/nrendo.2016.100] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Subclinical hypothyroidism is defined as serum levels of TSH above the upper limit of the reference range, in the presence of normal concentrations of total T4 or free T4. This biochemical profile might be an indication of mild hypothyroidism, with a potential increased risk of metabolic abnormalities and cardiovascular disease recorded among adults. Whether subclinical hypothyroidism results in adverse health outcomes among children is a matter of debate and so management of this condition remains challenging. Mild forms of untreated subclinical hypothyroidism do not seem to be associated with impairments in growth, bone health or neurocognitive outcome. However, ongoing scientific investigations have highlighted the presence of subtle proatherogenic abnormalities among children with modest elevations in their TSH levels. Although current findings are insufficient to recommend levothyroxine treatment for all children with mild asymptomatic forms of subclinical hypothyroidism, they highlight the potential need for assessment of cardiovascular risk among children with this condition. Increased understanding of the early metabolic risk factors associated with subclinical hypothyroidism in childhood will help to improve the management of affected individuals.
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Affiliation(s)
- Mariacarolina Salerno
- Department of Translational Medical Sciences - Pediatric Section, University of Naples Federico II, Naples, 80131, Italy
| | - Donatella Capalbo
- Department of Pediatrics, University Hospital Federico II, Naples, 80131, Italy
| | - Manuela Cerbone
- Department of Translational Medical Sciences - Pediatric Section, University of Naples Federico II, Naples, 80131, Italy
| | - Filippo De Luca
- Department of Pediatric, Gynecology, Microbiological and Biochemical Sciences, University of Messina, Messina, 98125, Italy
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61
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Jung JM, Jin HY, Chung ML. Feasibility of an Early Discontinuation of Thyroid Hormone Treatment in Very-Low-Birth-Weight Infants at Risk for Transient or Permanent Congenital Hypothyroidism. Horm Res Paediatr 2016; 85:131-9. [PMID: 26812645 DOI: 10.1159/000443399] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/16/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS This prospective study was conducted to investigate the feasibility of an early discontinuation of thyroid hormone treatment in very-low-birth-weight (VLBW) infants with congenital hypothyroidism (CH). METHODS We enrolled VLBW infants between January 2011 and December 2012. The infants were divided into the hypothyroid and normal thyroid function groups according to the results of a thyroid function test. We performed an early off-therapy trial at 24 months of age. RESULTS Of the 182 VLBW infants enrolled, 15 were lost to follow-up and 167 were finally enrolled. In total, 24 infants (14.4%) were assigned to the hypothyroid function group and were treated with thyroid hormone. Younger gestational age and a lower birth weight were associated with hypothyroid function. In the hypothyroid function group, hypothyroidism (HT) and hyperthyrotropinemia (HTT) were observed in 13 and 11 infants, respectively. There were no differences in the clinical characteristics between the HT and HTT groups. Overall, 24 infants discontinued thyroxine medication at 24 months of age after normal results had been confirmed by radiologic work-ups, including thyroid ultrasonography and technetium-99m scans. All infants were successfully weaned off thyroxine and maintained euthyroid function. CONCLUSION Early discontinuation of thyroid hormone replacement therapy is possible in the majority of VLBW infants with CH.
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Johnston RA, Paxton KL, Moore FR, Wayne RK, Smith TB. Seasonal gene expression in a migratory songbird. Mol Ecol 2016; 25:5680-5691. [DOI: 10.1111/mec.13879] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/17/2016] [Accepted: 09/21/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Rachel A. Johnston
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
| | - Kristina L. Paxton
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS 39406 USA
- Department of Biology University of Hawaii Hilo Hilo HI 96720 USA
| | - Frank R. Moore
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS 39406 USA
| | - Robert K. Wayne
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
| | - Thomas B. Smith
- Department of Ecology and Evolutionary Biology University of California, Los Angeles 610 Charles E Young Dr. South Rm. 4162 Los Angeles CA 90095 USA
- Center for Tropical Research Institute of the Environment and Sustainability University of California, Los Angeles Los Angeles CA 90095 USA
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63
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Henning Y, Szafranski K. Age-Dependent Changes of Monocarboxylate Transporter 8 Availability in the Postnatal Murine Retina. Front Cell Neurosci 2016; 10:205. [PMID: 27616981 PMCID: PMC4999454 DOI: 10.3389/fncel.2016.00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/15/2016] [Indexed: 12/12/2022] Open
Abstract
The thyroid hormones (TH) triiodothyronine (T3) and its prohormone thyroxine (T4) are crucial for retinal development and function, and increasing evidence points at TH dysregulation as a cause for retinal degenerative diseases. Thus, precise regulation of retinal TH supply is required for proper retinal function, but knowledge on these mechanisms is still fragmentary. Several transmembrane transporters have been described as key regulators of TH availability in target tissues of which the monocarboxylate transporter 8 (MCT8), a high affinity transporter for T4 and T3, plays an essential role in the central nervous system. Moreover, in the embryonic chicken retina, MCT8 is highly expressed, but the postnatal availability of MCT8 in the mammalian retina was not reported to date. In the present study, spatiotemporal retinal MCT8 availability was examined in mice of different age. For this purpose, we quantified expression levels of Mct8 via Real-Time Reverse-Transcriptase PCR in mouse eyecups (C57BL/6) of juvenile and adult age groups. Additionally, age-dependent MCT8 protein levels were quantified via Western blotting and localized via immunofluorescence confocal microscopy. While no difference in Mct8 expression levels could be detected between age groups, MCT8 protein levels in juvenile animals were about two times higher than in adult animals based on Western blot analyses. Immunohistochemical analyses showed that MCT8 immunoreactivity in the eyecup was restricted to the retina and the retinal pigment epithelium. In juvenile mice, MCT8 was broadly observed along the apical membrane of the retinal pigment epithelium, tightly surrounding photoreceptor outer segments. Distinct immunopositive staining was also detected in the inner nuclear layer and the ganglion cell layer. However, in adult specimens, immunoreactivity visibly declined in all layers, which was in line with Western blot analyses. Since MCT8 was abundantly present in juvenile and about twofold lower in adult retinae, our findings suggest a pivotal role of MCT8 especially during postnatal maturation. The present study provides novel insights into age-dependent retinal TH supply, which might help to understand different aspects regarding retinal development, function, and disorders.
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Affiliation(s)
- Yoshiyuki Henning
- Department of General Zoology, Faculty of Biology, University of Duisburg-Essen Essen, Germany
| | - Karol Szafranski
- Genome Analysis, Leibniz Institute on Aging - Fritz Lipmann Institute Jena, Germany
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Stavreva DA, Varticovski L, Levkova L, George AA, Davis L, Pegoraro G, Blazer V, Iwanowicz L, Hager GL. Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants. Toxicology 2016; 368-369:69-79. [PMID: 27528272 PMCID: PMC5069182 DOI: 10.1016/j.tox.2016.08.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 07/02/2016] [Accepted: 08/11/2016] [Indexed: 12/16/2022]
Abstract
Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)-tagged chimeric molecule of glucocorticoid receptor (GR) and the thyroid receptor beta (TRβ) from the cytoplasm to the nucleus in the presence of TR ligands. Unlike the constitutively nuclear TRβ, this GFP-GR-TRβ chimera is cytoplasmic in the absence of hormone while translocating to the nucleus in a time- and concentration-dependent manner upon stimulation with triiodothyronine (T3) and thyroid hormone analogue, TRIAC, while the reverse triiodothyronine (3,3',5'-triiodothyronine, or rT3) was inactive. Moreover, GFP-GR-TRβ chimera does not show any cross-reactivity with the GR-activating hormones, thus providing a clean system for the screening of TR beta-interacting EDCs. Using this assay, we demonstrated that Bisphenol A (BPA) and 3,3',5,5'-Tetrabromobisphenol (TBBPA) induced GFP-GR-TRβ translocation at micro molar concentrations. We screened over 100 concentrated water samples from different geographic locations in the United States and detected a low, but reproducible contamination in 53% of the samples. This system provides a novel high-throughput approach for screening for endocrine disrupting chemicals (EDCs) interacting with TR beta.
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Affiliation(s)
- Diana A Stavreva
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States.
| | - Lyuba Varticovski
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States
| | - Ludmila Levkova
- Department of Physics and Astronomy, Physics and Astronomy, University of Utah, Salt Lake City, UT, United States
| | - Anuja A George
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States
| | - Luke Davis
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States
| | - Gianluca Pegoraro
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States
| | - Vicki Blazer
- U.S. Geological Survey, Leetown Science Center, National Fish Health Research Laboratory, 11649 Leetown Road, Kearneysville, WV 25430, United States
| | - Luke Iwanowicz
- U.S. Geological Survey, Leetown Science Center, National Fish Health Research Laboratory, 11649 Leetown Road, Kearneysville, WV 25430, United States
| | - Gordon L Hager
- Laboratory of Receptor Biology and Gene Expression, Building 41, B602, 41 Library Dr., National Cancer Institute, NIH, Bethesda, MD 20892-5055, United States.
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Rajabi M, Sudha T, Darwish NHE, Davis PJ, Mousa SA. Synthesis of MR-49, a deiodinated analog of tetraiodothyroacetic acid (tetrac), as a novel pro-angiogenesis modulator. Bioorg Med Chem Lett 2016; 26:4112-6. [PMID: 27381084 DOI: 10.1016/j.bmcl.2016.06.064] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 01/29/2023]
Abstract
The tyrosine-based hormones 3,3',5-triiodo-l-thyronine (l-T3) and l-thyroxine (l-T4) that are produced by the thyroid gland control metabolic functions. Iodothyronine deiodinase enzymes convert l-T4 to l-T3, the form of thyroid hormone critical to genomic actions within cells and regulation of metabolism, and to reverse-l-T3, a hormone isoform that is largely inactive. We used tertiary amines in a study of deiodination based on derivatives of tetraiodothyroacetic acid (tetrac)-a naturally occurring derivative of l-T4-to mimic the action of the iodothyronine deiodinases and deiodination of the outer ring iodines. Deiodinated tetrac, MR-49, was found to be pro-angiogenic, with this activity exceeding that of l-T3 and l-T4 in a hemoglobin Matrigel® plug assay of angiogenesis. Tetrac is anti-angiogenic via several nongenomic pathways, and the present studies of MR-49 reveal the critical contribution of outer ring iodines to the angiogenic properties of thyroid hormone analogues, which may have utility as pro-angiogenic pharmaceuticals.
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Affiliation(s)
- Mehdi Rajabi
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY, USA
| | - Thangirala Sudha
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY, USA
| | - Noureldien H E Darwish
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY, USA; Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Paul J Davis
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY, USA; Department of Medicine, Albany Medical College, Albany, NY, USA
| | - Shaker A Mousa
- The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, 1 Discovery Drive, Rensselaer, NY, USA.
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66
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Ortiga-Carvalho TM, Chiamolera MI, Pazos-Moura CC, Wondisford FE. Hypothalamus-Pituitary-Thyroid Axis. Compr Physiol 2016; 6:1387-428. [PMID: 27347897 DOI: 10.1002/cphy.c150027] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hypothalamus-pituitary-thyroid (HPT) axis determines the set point of thyroid hormone (TH) production. Hypothalamic thyrotropin-releasing hormone (TRH) stimulates the synthesis and secretion of pituitary thyrotropin (thyroid-stimulating hormone, TSH), which acts at the thyroid to stimulate all steps of TH biosynthesis and secretion. The THs thyroxine (T4) and triiodothyronine (T3) control the secretion of TRH and TSH by negative feedback to maintain physiological levels of the main hormones of the HPT axis. Reduction of circulating TH levels due to primary thyroid failure results in increased TRH and TSH production, whereas the opposite occurs when circulating THs are in excess. Other neural, humoral, and local factors modulate the HPT axis and, in specific situations, determine alterations in the physiological function of the axis. The roles of THs are vital to nervous system development, linear growth, energetic metabolism, and thermogenesis. THs also regulate the hepatic metabolism of nutrients, fluid balance and the cardiovascular system. In cells, TH actions are mediated mainly by nuclear TH receptors (210), which modify gene expression. T3 is the preferred ligand of THR, whereas T4, the serum concentration of which is 100-fold higher than that of T3, undergoes extra-thyroidal conversion to T3. This conversion is catalyzed by 5'-deiodinases (D1 and D2), which are TH-activating enzymes. T4 can also be inactivated by conversion to reverse T3, which has very low affinity for THR, by 5-deiodinase (D3). The regulation of deiodinases, particularly D2, and TH transporters at the cell membrane control T3 availability, which is fundamental for TH action. © 2016 American Physiological Society. Compr Physiol 6:1387-1428, 2016.
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Affiliation(s)
- Tania M Ortiga-Carvalho
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil
| | - Maria I Chiamolera
- Department of Medicine, Escola Paulista de Medicina, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Carmen C Pazos-Moura
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil
| | - Fredic E Wondisford
- Department of Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA
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67
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Abstract
The nongenomic actions of thyroid hormone begin at receptors in the plasma membrane, mitochondria or cytoplasm. These receptors can share structural homologies with nuclear thyroid hormone receptors (TRs) that mediate transcriptional actions of T3, or have no homologies with TR, such as the plasma membrane receptor on integrin αvβ3. Nongenomic actions initiated at the plasma membrane by T4 via integrin αvβ3 can induce gene expression that affects angiogenesis and cell proliferation, therefore, both nongenomic and genomic effects can overlap in the nucleus. In the cytoplasm, a truncated TRα isoform mediates T4-dependent regulation of intracellular microfilament organization, contributing to cell and tissue structure. p30 TRα1 is another shortened TR isoform found at the plasma membrane that binds T3 and mediates nongenomic hormonal effects in bone cells. T3 and 3,5-diiodo-L-thyronine are important to the complex nongenomic regulation of cellular respiration in mitochondria. Thus, nongenomic actions expand the repertoire of cellular events controlled by thyroid hormone and can modulate TR-dependent nuclear events. Here, we review the experimental approaches required to define nongenomic actions of the hormone, enumerate the known nongenomic effects of the hormone and their molecular basis, and discuss the possible physiological or pathophysiological consequences of these actions.
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Affiliation(s)
- Paul J Davis
- Pharmaceutical Research Institute, Albany College of Pharmacy &Health Sciences, One Discovery Drive, Rennselaer, New York 12144, USA
| | - Fernando Goglia
- Dipartimento di Scienze e Tecnologie, Università degli studi del Sannio, Via Port'Arsa 11, 82100, Benevento, Italy
| | - Jack L Leonard
- Department of Microbiology &Physiological Systems, University of Massachusetts Medical School, 368 Plantation Street, Worcester, Massachusetts 01605, USA
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68
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Kersseboom S, Horn S, Visser WE, Chen J, Friesema ECH, Vaurs-Barrière C, Peeters RP, Heuer H, Visser TJ. In vitro and mouse studies supporting therapeutic utility of triiodothyroacetic acid in MCT8 deficiency. Mol Endocrinol 2015; 28:1961-70. [PMID: 25389909 DOI: 10.1210/me.2014-1135] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Monocarboxylate transporter 8 (MCT8) transports thyroid hormone (TH) across the plasma membrane. Mutations in MCT8 result in the Allan-Herndon-Dudley syndrome, comprising severe psychomotor retardation and elevated serum T3 levels. Because the neurological symptoms are most likely caused by a lack of TH transport into the central nervous system, the administration of a TH analog that does not require MCT8 for cellular uptake may represent a therapeutic strategy. Here, we investigated the therapeutic potential of the biologically active T3 metabolite Triac (TA3) by studying TA3 transport, metabolism, and action both in vitro and in vivo. Incubation of SH-SY5Y neuroblastoma cells and MO3.13 oligodendrocytes with labeled substrates showed a time-dependent uptake of T3 and TA3. In intact SH-SY5Y cells, both T3 and TA3 were degraded by endogenous type 3 deiodinase, and they influenced gene expression to a similar extent. Fibroblasts from MCT8 patients showed an impaired T3 uptake compared with controls, whereas TA3 uptake was similar in patient and control fibroblasts. In transfected cells, TA3 did not show significant transport by MCT8. Most importantly, treatment of athyroid Pax8-knockout mice and Mct8/Oatp1c1-double knockout mice between postnatal days 1 and 12 with TA3 restored T3-dependent neural differentiation in the cerebral and cerebellar cortex, indicating that TA3 can replace T3 in promoting brain development. In conclusion, we demonstrated uptake of TA3 in neuronal cells and in fibroblasts of MCT8 patients and similar gene responses to T3 and TA3. This indicates that TA3 bypasses MCT8 and may be used to improve the neural status of MCT8 patients.
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Affiliation(s)
- Simone Kersseboom
- Department of Internal Medicine (S.K., W.E.V., E.C.H.F., R.P.P., T.J.V.) and Rotterdam Thyroid Center (S.K., W.E.V., R.P.P., T.J.V.), Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands; Leibniz Institute for Age Research/Fritz Lipmann Institute (S.H., J.C., H.H.), Jena, Germany; Inserm (C.V.-B.), Unité Mixte de Recherche (UMR) 1103, and Centre National de la Recherche Scientifique (C.V.-B.), UMR6293, F-63001 Clermont-Ferrand, France; Clermont Université (C.V.-B.), Université d'Auvergne, Laboratoire GReD, BP 10448, F-63000 Clermont-Ferrand, France; and Leibniz Research Institute for Environmental Medicine (J.C., H.H.), Düsseldorf, Germany
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Chen C, Ma Q, Chen X, Zhong M, Deng P, Zhu G, Zhang Y, Zhang L, Yang Z, Zhang K, Guo L, Wang L, Yu Z, Zhou Z. Thyroid Hormone-Otx2 Signaling Is Required for Embryonic Ventral Midbrain Neural Stem Cells Differentiated into Dopamine Neurons. Stem Cells Dev 2015; 24:1751-65. [PMID: 25867707 DOI: 10.1089/scd.2014.0489] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Midbrain dopamine (DA) neurons are essential for maintaining multiple brain functions. These neurons have also been implicated in relation with diverse neurological disorders. However, how these neurons are developed from neuronal stem cells (NSCs) remains largely unknown. In this study, we provide both in vivo and in vitro evidence that the thyroid hormone, an important physiological factor for brain development, promotes DA neuron differentiation from embryonic ventral midbrain (VM) NSCs. We find that thyroid hormone deficiency during development reduces the midbrain DA neuron number, downregulates the expression of tyrosine hydroxylase (TH) and the dopamine transporter (DAT), and impairs the DA neuron-dependent motor behavior. In addition, thyroid hormone treatment during VM NSC differentiation in vitro increases the production of DA neurons and upregulates the expression of TH and DAT. We also found that the thyroid hormone enhances the expression of Otx2, an important determinant of DA neurogenesis, during DA neuron differentiation. Our in vitro gene silencing experiments indicate that Otx2 is required for thyroid hormone-dependent DA neuron differentiation from embryonic VM NSCs. Finally, we revealed both in vivo and in vitro that the thyroid hormone receptor alpha 1 is expressed in embryonic VM NSCs. Furthermore, it participates in the effects of thyroid hormone-induced Otx2 upregulation and DA neuron differentiation. These data demonstrate the role and molecular mechanisms of how the thyroid hormone regulates DA neuron differentiation from embryonic VM NSCs, particularly providing new mechanisms and a potential strategy for generating dopamine neurons from NSCs.
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Affiliation(s)
- Chunhai Chen
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Qinglong Ma
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Xiaowei Chen
- 2 Brain Research Center, Third Military Medical University , Chongqing, China
| | - Min Zhong
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Ping Deng
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Gang Zhu
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Yanwen Zhang
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Lei Zhang
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Zhiqi Yang
- 2 Brain Research Center, Third Military Medical University , Chongqing, China
| | - Kuan Zhang
- 2 Brain Research Center, Third Military Medical University , Chongqing, China
| | - Lu Guo
- 3 Department of Neurology, Daping Hospital, Third Military Medical University , Chongqing, China
| | - Liting Wang
- 4 Biomedical Analysis Center, Third Military Medical University , Chongqing, China
| | - Zhengping Yu
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
| | - Zhou Zhou
- 1 Department of Occupational Health, Third Military Medical University , Chongqing, China
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Dezonne RS, Lima FRS, Trentin AG, Gomes FC. Thyroid hormone and astroglia: endocrine control of the neural environment. J Neuroendocrinol 2015; 27:435-45. [PMID: 25855519 DOI: 10.1111/jne.12283] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 02/03/2023]
Abstract
Thyroid hormones (THs) play key roles in brain development and function. The lack of THs during childhood is associated with the impairment of several neuronal connections, cognitive deficits and mental disorders. Several lines of evidence point to astrocytes as TH targets and as mediators of TH action in the central nervous system; however, the mechanisms underlying these events are still not completely known. In this review, we focus on advances in our understanding of the effects of THs on astroglial cells and the impact of these effects on neurone-astrocyte interactions. First, we discuss the signalling pathways involved in TH metabolism and the molecular mechanisms underlying TH receptor function. Then, we discuss data related to the effects of THs on astroglial cells, as well as studies regarding the generation of mutant TH receptor transgenic mice that have contributed to our understanding of TH function in brain development. We argue that astrocytes are key mediators of hormone actions on development of the cerebral cortex and cerebellum and that the identification of the molecules and pathways involved in these events might be important for determining the molecular-level basis of the neural deficits associated with endocrine diseases.
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Affiliation(s)
- R S Dezonne
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - F R S Lima
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - A G Trentin
- Departamento de Biologia Celular, Centro de Ciências Biológicas, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - F C Gomes
- Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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71
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Kapoor R, Fanibunda SE, Desouza LA, Guha SK, Vaidya VA. Perspectives on thyroid hormone action in adult neurogenesis. J Neurochem 2015; 133:599-616. [DOI: 10.1111/jnc.13093] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/18/2015] [Accepted: 02/24/2015] [Indexed: 12/25/2022]
Affiliation(s)
- Richa Kapoor
- Department of Biological Sciences; Tata Institute of Fundamental Research; Mumbai India
| | - Sashaina E. Fanibunda
- Department of Biological Sciences; Tata Institute of Fundamental Research; Mumbai India
| | - Lynette A. Desouza
- Department of Biological Sciences; Tata Institute of Fundamental Research; Mumbai India
| | - Suman K. Guha
- Department of Biological Sciences; Tata Institute of Fundamental Research; Mumbai India
| | - Vidita A. Vaidya
- Department of Biological Sciences; Tata Institute of Fundamental Research; Mumbai India
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Zhao XS, Fu WY, Hung KW, Chien WWY, Li Z, Fu AK, Ip NY. NRC-interacting factor directs neurite outgrowth in an activity-dependent manner. Neuroscience 2015; 289:207-13. [PMID: 25573434 DOI: 10.1016/j.neuroscience.2014.12.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 12/05/2014] [Accepted: 12/24/2014] [Indexed: 11/18/2022]
Abstract
Nuclear hormone receptor coregulator-interacting factor 1 (NIF-1) is a zinc finger nuclear protein that was initially identified to enhance nuclear hormone receptor transcription via its interaction with nuclear hormone receptor coregulator (NRC). NIF-1 may regulate gene transcription either by modulating general transcriptional machinery or remodeling chromatin structure through interactions with specific protein partners. We previously reported that the cytoplasmic/nuclear localization of NIF-1 is regulated by the neuronal Cdk5 activator p35, suggesting potential neuronal functions for NIF-1. The present study reveals that NIF-1 plays critical roles in regulating neuronal morphogenesis at early stages. NIF-1 was prominently expressed in the nuclei of developing rat cortical neurons. Knockdown of NIF-1 expression attenuated both neurite outgrowth in cultured cortical neurons and retinoic acid (RA)-treated Neuro-2a neuroblastoma cells. Furthermore, activity-induced Ca(2+) influx, which is critical for neuronal morphogenesis, stimulated the nuclear localization of NIF-1 in cortical neurons. Suppression of NIF-1 expression reduced the up-regulation of neuronal activity-dependent gene transcription. These findings collectively suggest that NIF-1 directs neuronal morphogenesis during early developmental stages through modulating activity-dependent gene transcription.
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Affiliation(s)
- X-S Zhao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W-Y Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - K-W Hung
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W W Y Chien
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Z Li
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - A K Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - N Y Ip
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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73
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Kocaturk T, Ergin K, Cesur G, Evlicoglu GE, Cakmak H. The effect of methimazole-induced postnatal hypothyroidism on the retinal maturation and on the Sirtuin 2 level. Cutan Ocul Toxicol 2015; 35:36-40. [PMID: 25758293 DOI: 10.3109/15569527.2015.1007509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To investigate the effect of methimazole-induced postnatal hypothyroidism on the retinal maturation and to study Sirtuin 2 (SIRT2) level in the hypothyroidic rat retina. METHODS Twenty newborn Wistar albino rat pups were used in this prospective, randomized study. Wistar albino rats, weight 250-300 g, were impregnated (without addition of any drug) and were fed normally. Rat pups were randomly divided into two groups and were fed with breast milk. After weaning till they were 90 days of age, rat pups received the same water as their lactating mothers drank. Group 1 (methimazole (MMI)-induced hypothyroidy group), rats were given MMI-water, whereas, in Group 2, normal tap water. When the pups were 90 days of age, 20 rat pups were decapitated and the eyes were isolated. Eyes were investigated using histological, histomorphometric and immunohistochemistrical techniques. RESULTS No histological difference was seen between the groups stained with hematoxylin and eosin. In both groups the retinal layer structures and cells were observed as normal. The examples in the groups had a normal distribution for retinal thickness (pixel) measure. The mean value (mean ± std. deviation) was 554.7 ± 228.4 in the control group and 494.7 ± 129.4 in the hypothyroidy group. There was no significance between the groups in terms of retinal thickness (p = 0.231). However, immunohistochemistry revealed that SIRT2 was weaker stained in the ganglion cell layer and visual cell layer in the hypothyroidy group compared to the control group. CONCLUSION Postnatal hypothyroidism altered the retinal cytoarchitecture and layering which are regulated by thyroid hormones (THs) during retinal maturation in the postnatal period. THs may act by the induction of the SIRT family proteins or through their receptors. Postnatal screenings for THs levels are very important to provide normal retinal development.
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Affiliation(s)
| | | | - Gokhan Cesur
- c Department of Physiology , Adnan Menderes University Faculty of Medicine , Aydin , Turkey
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74
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Parichy DM, Spiewak JE. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution. Pigment Cell Melanoma Res 2014; 28:31-50. [PMID: 25421288 DOI: 10.1111/pcmr.12332] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 11/20/2014] [Indexed: 12/25/2022]
Abstract
Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve-associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns.
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Affiliation(s)
- David M Parichy
- Department of Biology, University of Washington, Seattle, WA, USA
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75
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Korzeniewski SJ, Soto-Rivera CL, Fichorova RN, Allred E, Kuban KCK, O’Shea TM, Paneth N, Agus M, Dammann O, Leviton A. Are preterm newborns who have relative hyperthyrotropinemia at increased risk of brain damage? J Pediatr Endocrinol Metab 2014; 27:1077-88. [PMID: 24897395 PMCID: PMC4317282 DOI: 10.1515/jpem-2014-0059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 04/30/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND We sought to disentangle the contributions of hyperthyrotropinemia (an indicator of thyroid dysfunction) (HTT) and intermittent or sustained systemic inflammation (ISSI) to structural and functional indicators of brain damage. METHODS We measured the concentrations of thyroid-stimulating hormone (TSH) on day 14 and of 25 inflammation-related proteins in blood collected during the first 2 postnatal weeks from 786 infants born before the 28th week of gestation who were not considered to have hypothyroidism. We defined hyperthyrotropinemia (HTT) as a TSH concentration in the highest quartile for gestational age on postnatal day 14 and ISSI was defined as a concentration in the top quartile for gestational age of a specific inflammation-related protein on 2 separate days a week apart during the first 2 postnatal weeks. We first assessed the risk of brain damage indicators by comparing 1) neonates who had HTT to those without (regardless of ISSI) and 2) neonates with HTT only, ISSI only, or HTT+ISSI to those who were exposed to neither HTT nor ISSI. RESULTS In univariable models that compared those with HTT to those without, HTT was not significantly associated with any indicator of brain damage. In models that compared HTT only, ISSI only, and HTT+ISSI to those with neither, children with ISSI only or with HTT+ISSI were at significantly higher risk of ventriculomegaly [odds ratios (ORs) 2-6], whereas those with HTT only were at significantly reduced risk of a hypoechoic lesion (ORs 0.2-0.4). Children with HTT only had a higher risk of quadriparesis and those with ISSI alone had a higher risk of hemiparesis (ORs 1.6-2.4). Elevated risk of a very low mental development score was associated with both ISSI only and HTT+ISSI, whereas a very low motor development score and microcephaly were associated with HTT+ISSI. CONCLUSIONS The association of HTT with increased or decreased risk of indicators of brain damage depends on the presence or absence of ISSI.
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Affiliation(s)
- Steven J. Korzeniewski
- Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, Maryland, and Detroit, Michigan
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan
| | - Carmen L. Soto-Rivera
- Division of Endocrinology, Boston Children’s Hospital, Harvard Medical School, Boston, MA
| | - Raina N. Fichorova
- Departments of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women’s Hospital and Harvard Medical School
| | - Elizabeth Allred
- Neurology Departments, Boston Children’s Hospital, and Harvard Medical School, Boston, MA
| | - Karl C. K. Kuban
- Departments of Pediatrics, Boston Medical Center and Boston University, Boston, MA
| | | | - Nigel Paneth
- Department of Epidemiology, Michigan State University, East Lansing, MI
| | - Michael Agus
- Division of Endocrinology, Boston Children’s Hospital, Harvard Medical School, Boston, MA
| | - Olaf Dammann
- Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, MA
- Neuroepidemiology Unit, Hannover School of Medicine, Hannover, Germany
| | - Alan Leviton
- Neurology Departments, Boston Children’s Hospital, and Harvard Medical School, Boston, MA
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Nam SM, Kim YN, Yoo DY, Yi SS, Choi JH, Hwang IK, Seong JK, Yoon YS. Hypothyroidism affects astrocyte and microglial morphology in type 2 diabetes. Neural Regen Res 2014; 8:2458-67. [PMID: 25206556 PMCID: PMC4146114 DOI: 10.3969/j.issn.1673-5374.2013.26.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/25/2013] [Indexed: 12/03/2022] Open
Abstract
In the present study, we investigated the effects of hypothyroidism on the morphology of astrocytes and microglia in the hippocampus of Zucker diabetic fatty rats and Zucker lean control rats. To induce hypothyroidism, Zucker lean control and Zucker diabetic fatty rats at 7 weeks of age orally received the vehicle or methimazole, an anti-thyroid drug, treatment for 5 weeks and were sacrificed at 12 weeks of age in all groups for blood chemistry and immunohistochemical staining. In the methimazole-treated Zucker lean control and Zucker diabetic fatty rats, the serum circulating thyronine (T3) and thyroxine (T4) levels were significantly decreased compared to levels observed in the vehicle-treated Zucker lean control or Zucker diabetic fatty rats. This reduction was more prominent in the methimazole-treated Zucker diabetic fatty group. Glial fibrillary acidic protein immunoreactive astrocytes and ionized calcium-binding adapter molecule 1 (Iba-1)-immunoreactive microglia in the Zucker lean control and Zucker diabetic fatty group were diffusely detected in the hippocampal CA1 region and dentate gyrus. There were no significant differences in the glial fibrillary acidic protein and Iba-1 immunoreactivity in the CA1 region and dentate gyrus between Zucker lean control and Zucker diabetic fatty groups. However, in the methimazole-treated Zucker lean control and Zucker diabetic fatty groups, the processes of glial fibrillary acidic protein tive astrocytes and Iba-1 immunoreactive microglia, were significantly decreased in both the CA1 region and dentate gyrus compared to that in the vehicle-treated Zucker lean control and Zucker diabetic fatty groups. These results suggest that diabetes has no effect on the morphology of astrocytes and microglia and that hypothyroidism during the onset of diabetes prominently reduces the processes of astrocytes and microglia.
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Affiliation(s)
- Sung Min Nam
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
| | - Yo Na Kim
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
| | - Dae Young Yoo
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
| | - Sun Shin Yi
- Department of Biomedical Laboratory Science, College of Biomedical Sciences, Soonchunhyang University, Asan 336-745, South Korea
| | - Jung Hoon Choi
- Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, South Korea
| | - In Koo Hwang
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
| | - Je Kyung Seong
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
| | - Yeo Sung Yoon
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
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Cho MS, Cho GS, Park SH, Jung MH, Suh BK, Koh DG. Earlier re-evaluation may be possible in pediatric patients with eutopic congenital hypothyroidism requiring lower L-thyroxine doses. Ann Pediatr Endocrinol Metab 2014; 19:141-5. [PMID: 25346918 PMCID: PMC4208263 DOI: 10.6065/apem.2014.19.3.141] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 09/15/2014] [Accepted: 09/24/2014] [Indexed: 11/20/2022] Open
Abstract
PURPOSE The incidence of congenital hypothyroidism (CH) has increased in several countries. Lower cut-off in screening programs have led to an increase in the proportion of transient hypothyroidism (TH) cases diagnosed, leading to debate on the associated clinical and economic impact. This study aimed to identify factors that would allow discrimination between TH and permanent CH (PH) in patients with a eutopic thyroid gland. METHODS Sixty-six patients with CH from 3 different hospitals were studied: 26 cases of TH, and 40 cases of PH. Laboratory findings and clinical parameters were analysed in 56 patients with eutopic thyroid gland. RESULTS Initial serum thyroid stimulating hormone levels and L-thyroxine dose at 12 and 24 months of age were significantly higher in PH than TH patients with a eutopic thyroid gland. The area under the curve for the 12-month and 24-month dose for the prediction of TH in eutopic CH was 0.799 (95% confidence interval [CI], 0.678-0.919; P<0.001) and 0.925 (95% CI, 0.837-1.000; P<0.001), respectively. The optimum 12-month and 24-month dose in predicting TH is 3.25 µg/kg (12-month: sensitivity, 87.1%; specificity, 68.0%; 24-month: sensitivity 93.5%, specificity 88%). CONCLUSION Infants with CH requiring lower L-thyroxine doses (<3.25 µg/kg) are likely to have TH, and thus might be re-evaluated at 12 months or 24 months rather than 3 years of age.
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Affiliation(s)
- Min Sun Cho
- Department of Pediatrics, The Catholic University of Korea, St. Paul's Hospital, Seoul, Korea
| | - Gyung Sun Cho
- Department of Pediatrics, The Catholic University of Korea, Bucheon St. Mary's Hospital, Bucheon, Korea
| | - So Hyun Park
- Department of Pediatrics, The Catholic University of Korea, St. Vincent's Hospital, Suwon, Korea
| | - Min Ho Jung
- Department of Pediatrics, The Catholic University of Korea, Yeouido St. Mary's Hospital, Seoul, Korea
| | - Byung Kyu Suh
- Department of Pediatrics, The Catholic University of Korea, Seoul St. Mary's Hospital, Seoul, Korea
| | - Dae Gyun Koh
- Department of Pediatrics, The Catholic University of Korea, St. Vincent's Hospital, Suwon, Korea
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van Wassenaer-Leemhuis A, Ares S, Golombek S, Kok J, Paneth N, Kase J, LaGamma EF. Thyroid hormone supplementation in preterm infants born before 28 weeks gestational age and neurodevelopmental outcome at age 36 months. Thyroid 2014; 24:1162-9. [PMID: 24684245 PMCID: PMC4080860 DOI: 10.1089/thy.2013.0618] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Thyroid hormones are required for normal brain maturation, and neonatal plasma thyroid hormone concentrations are low in infants less than 28 weeks gestation. It is not known whether treatment of such infants with thyroid hormone improves neurodevelopmental outcome. METHODS At three years corrected age, mental, motor, and neurological development was assessed in infants born at less than 28 weeks gestational age who had participated in a phase 1 trial of differing doses and modes of administration of thyroid hormone. The trial's endpoints were thyroid hormone (thyroxine, T4) and thyotropin plasma concentrations in eight study arms: six treated with T4 [4, 8, and 16 μg/(kg · day)], bolus or continuous], one treated with iodine only, and one treated with placebo. Follow-up at three years was not part of the original study goals. Developmental index scores, rates of cerebral palsy (CP), and rates of adverse outcome (death or moderate to severe delay in development and/or disabling CP) were compared between the eight study groups and between groups combined by dosage level, and between infants with and without T4 supplementation. RESULTS Of 166 randomized infants, 32 (19%) died in the neonatal period. Of the 134 survivors, follow-up results were available for 89 children (66%). Mental and motor development and rates of cerebral palsy did not differ in any of the comparisons made. CONCLUSION In this study, no differences in neurodevelopment were found in relation to thyroid hormone treatment, but power was insufficient to detect any but very large differences.
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Affiliation(s)
| | - Susana Ares
- University Hospital La Paz, Neonatology Unit, Autonomous University of Madrid, Madrid, Spain
| | - Sergio Golombek
- The Regional Neonatal Center, Maria Fareri Children's Hospital at Westchester Medical Center, New York Medical College, Valhalla, New York
| | - Joke Kok
- Emma Children's Hospital-Academic Medical Center, Amsterdam, Netherlands
| | - Nigel Paneth
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, Michigan
- Department of Pediatrics and Human Development, Michigan State University, East Lansing, Michigan
| | - Jordan Kase
- The Regional Neonatal Center, Maria Fareri Children's Hospital at Westchester Medical Center, New York Medical College, Valhalla, New York
| | - Edmund F. LaGamma
- The Regional Neonatal Center, Maria Fareri Children's Hospital at Westchester Medical Center, New York Medical College, Valhalla, New York
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Duarte-Guterman P, Navarro-Martín L, Trudeau VL. Mechanisms of crosstalk between endocrine systems: regulation of sex steroid hormone synthesis and action by thyroid hormones. Gen Comp Endocrinol 2014; 203:69-85. [PMID: 24685768 DOI: 10.1016/j.ygcen.2014.03.015] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 03/15/2014] [Accepted: 03/17/2014] [Indexed: 01/20/2023]
Abstract
Thyroid hormones (THs) are well-known regulators of development and metabolism in vertebrates. There is increasing evidence that THs are also involved in gonadal differentiation and reproductive function. Changes in TH status affect sex ratios in developing fish and frogs and reproduction (e.g., fertility), hormone levels, and gonad morphology in adults of species of different vertebrates. In this review, we have summarized and compared the evidence for cross-talk between the steroid hormone and thyroid axes and present a comparative model. We gave special attention to TH regulation of sex steroid synthesis and action in both the brain and gonad, since these are important for gonad development and brain sexual differentiation and have been studied in many species. We also reviewed research showing that there is a TH system, including receptors and enzymes, in the brains and gonads in developing and adult vertebrates. Our analysis shows that THs influences sex steroid hormone synthesis in vertebrates, ranging from fish to pigs. This concept of crosstalk and conserved hormone interaction has implications for our understanding of the role of THs in reproduction, and how these processes may be dysregulated by environmental endocrine disruptors.
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Affiliation(s)
- Paula Duarte-Guterman
- Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada.
| | - Laia Navarro-Martín
- Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Vance L Trudeau
- Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada
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Abstract
The thyroid hormones, thyroxine (T4) and triiodothyronine (T3), are essential for normal growth and development of the fetus. Their bioavailability in utero depends on development of the fetal hypothalamic-pituitary-thyroid gland axis and the abundance of thyroid hormone transporters and deiodinases that influence tissue levels of bioactive hormone. Fetal T4 and T3 concentrations are also affected by gestational age, nutritional and endocrine conditions in utero, and placental permeability to maternal thyroid hormones, which varies among species with placental morphology. Thyroid hormones are required for the general accretion of fetal mass and to trigger discrete developmental events in the fetal brain and somatic tissues from early in gestation. They also promote terminal differentiation of fetal tissues closer to term and are important in mediating the prepartum maturational effects of the glucocorticoids that ensure neonatal viability. Thyroid hormones act directly through anabolic effects on fetal metabolism and the stimulation of fetal oxygen consumption. They also act indirectly by controlling the bioavailability and effectiveness of other hormones and growth factors that influence fetal development such as the catecholamines and insulin-like growth factors (IGFs). By regulating tissue accretion and differentiation near term, fetal thyroid hormones ensure activation of physiological processes essential for survival at birth such as pulmonary gas exchange, thermogenesis, hepatic glucogenesis, and cardiac adaptations. This review examines the developmental control of fetal T4 and T3 bioavailability and discusses the role of these hormones in fetal growth and development with particular emphasis on maturation of somatic tissues critical for survival immediately at birth.
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Affiliation(s)
- A J Forhead
- Department of PhysiologyDevelopment and Neuroscience, University of Cambridge, Physiology Building, Downing Street, Cambridge CB2 3EG, UKDepartment of Biological and Medical SciencesOxford Brookes University, Oxford OX3 0BP, UKDepartment of PhysiologyDevelopment and Neuroscience, University of Cambridge, Physiology Building, Downing Street, Cambridge CB2 3EG, UKDepartment of Biological and Medical SciencesOxford Brookes University, Oxford OX3 0BP, UK
| | - A L Fowden
- Department of PhysiologyDevelopment and Neuroscience, University of Cambridge, Physiology Building, Downing Street, Cambridge CB2 3EG, UKDepartment of Biological and Medical SciencesOxford Brookes University, Oxford OX3 0BP, UK
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Campinho MA, Saraiva J, Florindo C, Power DM. Maternal thyroid hormones are essential for neural development in zebrafish. Mol Endocrinol 2014; 28:1136-49. [PMID: 24877564 DOI: 10.1210/me.2014-1032] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Teleost eggs contain an abundant store of maternal thyroid hormones (THs), and early in zebrafish embryonic development, all the genes necessary for TH signaling are expressed. Nonetheless the function of THs in embryonic development remains elusive. To test the hypothesis that THs are fundamental for zebrafish embryonic development, an monocarboxilic transporter 8 (Mct8) knockdown strategy was deployed to prevent maternal TH uptake. Absence of maternal THs did not affect early specification of the neural epithelia but profoundly modified later dorsal specification of the brain and spinal cord as well as specific neuron differentiation. Maternal THs acted upstream of pax2a, pax7, and pax8 genes but downstream of shha and fgf8a signaling. The lack of inhibitory spinal cord interneurons and increased motoneurons in the mct8 morphants is consistent with their stiff axial body and impaired mobility. The mct8 mutations are associated with X-linked mental retardation in humans, and the cellular and molecular consequences of MCT8 knockdown during embryonic development in zebrafish provides new insight into the potential role of THs in this condition.
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Affiliation(s)
- Marco A Campinho
- Comparative Endocrinology and Integrative Biology Group (M.A.C., J.S., D.M.P.), Centre of Marine Sciences, and Departamento de Ciências Biomédicas e Medicina and Centro de Biomedicina Molecular e Estrutural (C.F.), Universidade do Algarve, 8005-139 Faro, Portugal
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Pesce L, Kopp P. Iodide transport: implications for health and disease. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2014; 2014:8. [PMID: 25009573 PMCID: PMC4089555 DOI: 10.1186/1687-9856-2014-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 05/22/2014] [Indexed: 12/15/2022]
Abstract
Disorders of the thyroid gland are among the most common conditions diagnosed and managed by pediatric endocrinologists. Thyroid hormone synthesis depends on normal iodide transport and knowledge of its regulation is fundamental to understand the etiology and management of congenital and acquired thyroid conditions such as hypothyroidism and hyperthyroidism. The ability of the thyroid to concentrate iodine is also widely used as a tool for the diagnosis of thyroid diseases and in the management and follow up of the most common type of endocrine cancers: papillary and follicular thyroid cancer. More recently, the regulation of iodide transport has also been the center of attention to improve the management of poorly differentiated thyroid cancer. Iodine deficiency disorders (goiter, impaired mental development) due to insufficient nutritional intake remain a universal public health problem. Thyroid function can also be influenced by medications that contain iodide or interfere with iodide metabolism such as iodinated contrast agents, povidone, lithium and amiodarone. In addition, some environmental pollutants such as perchlorate, thiocyanate and nitrates may affect iodide transport. Furthermore, nuclear accidents increase the risk of developing thyroid cancer and the therapy used to prevent exposure to these isotopes relies on the ability of the thyroid to concentrate iodine. The array of disorders involving iodide transport affect individuals during the whole life span and, if undiagnosed or improperly managed, they can have a profound impact on growth, metabolism, cognitive development and quality of life.
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Affiliation(s)
- Liuska Pesce
- Stead Family Department of Pediatrics, Division of Pediatric Endocrinology and Diabetes, University of Iowa Carver School of Medicine, Iowa City, Iowa 52242, USA
| | - Peter Kopp
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
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83
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Ramot Y, Paus R. Harnessing neuroendocrine controls of keratin expression: A new therapeutic strategy for skin diseases? Bioessays 2014; 36:672-86. [DOI: 10.1002/bies.201400006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yuval Ramot
- Department of Dermatology; Hadassah - Hebrew University Medical Center; Jerusalem Israel
| | - Ralf Paus
- Dermatology Research Centre; Institute of Inflammation and Repair; University of Manchester; Manchester UK
- Laboratory for Hair Research and Regenerative Medicine, Department of Dermatology; University of Münster; Münster Germany
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Abstract
Exposure to polybrominated diphenyl ethers (PBDE) during sensitive developmental windows can interfere with cognitive function and behavior, which are critical components of neurodevelopment. The association between developmental exposure to PBDEs and neurodevelopment has been extensively studied using animal models. In this review, we focus on the accumulating evidence in humans. Despite methodological, geographical, and temporal differences between studies, the majority of the epidemiologic evidence supports that early life exposure to PBDEs measured during pregnancy and/or during childhood is detrimental to child neurodevelopment in domains related to child behavior, cognition, and motor skills. While the precise mechanism of action of PBDEs on neurodevelopment is unknown, PBDE-induced neurotoxicity via thyroid hormone disruption and direct action of PBDEs on the developing brain have been proposed and tested. Additional studies are suggested to better understand how early life and/or childhood PBDE exposures, including exposure to specific PBDE congeners, impact neurodevelopmental indices.
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85
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Freitas J, Miller N, Mengeling BJ, Xia M, Huang R, Houck K, Rietjens IMCM, Furlow JD, Murk AJ. Identification of thyroid hormone receptor active compounds using a quantitative high-throughput screening platform. Curr Chem Genom Transl Med 2014; 8:36-46. [PMID: 24772387 PMCID: PMC3999704 DOI: 10.2174/2213988501408010036] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 12/09/2013] [Accepted: 12/12/2013] [Indexed: 02/02/2023] Open
Abstract
To adapt the use of GH3.TRE-Luc reporter gene cell line for a quantitative high-throughput screening (qHTS)
platform, we miniaturized the reporter gene assay to a 1536-well plate format. 1280 chemicals from the Library of Pharmacologically
Active Compounds (LOPAC) and the National Toxicology Program (NTP) 1408 compound collection
were analyzed to identify potential thyroid hormone receptor (TR) agonists and antagonists. Of the 2688 compounds
tested, eight scored as potential TR agonists when the positive hit cut-off was defined at ≥10% efficacy, relative to maximal
triiodothyronine (T3) induction, and with only one of those compounds reaching ≥20% efficacy. One common class of
compounds positive in the agonist assays were retinoids such as all-trans retinoic acid, which are likely acting via the retinoid-X receptor, the heterodimer partner with the TR. Five potential TR antagonists were identified, including the antiallergy
drug tranilast and the anxiolytic drug SB 205384 but also some cytotoxic compounds like 5-fluorouracil. None of
the inactive compounds were structurally related to T3, nor had been reported elsewhere to be thyroid hormone disruptors,
so false negatives were not detected. None of the low potency (>100µM) TR agonists resembled T3 or T4, thus these may
not bind directly in the ligand-binding pocket of the receptor. For TR agonists, in the qHTS, a hit cut-off of ≥20% efficacy
at 100 µM may avoid identification of positives with low or no physiological relevance. The miniaturized GH3.TRE-Luc
assay offers a promising addition to the in vitro test battery for endocrine disruption, and given the low percentage of
compounds testing positive, its high-throughput nature is an important advantage for future toxicological screening.
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Affiliation(s)
- Jaime Freitas
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands ; Group of Cell Activation and Gene Expression, Institute for Molecular and Cellular Biology, University of Porto, Porto, Portugal
| | - Nicole Miller
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Brenda J Mengeling
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis 95616, USA
| | - Menghang Xia
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ruili Huang
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Keith Houck
- National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
| | - J David Furlow
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis 95616, USA
| | - Albertinka J Murk
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE Wageningen, The Netherlands ; Subdepartment of Environmental Technology, Wageningen University, and Wageningen-IMARES, Axis Z (Building number 118), Room TT.1.100, Bornse Weilanden 96708, WG Wageningen, The Netherlands
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86
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Lim G, Lee YK, Han HS. Early discontinuation of thyroxine therapy is possible in most very low-birthweight infants with hypothyroidism detected by screening. Acta Paediatr 2014; 103:e123-9. [PMID: 24117608 DOI: 10.1111/apa.12450] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 09/08/2013] [Accepted: 10/01/2013] [Indexed: 11/30/2022]
Abstract
AIM To determine the feasibility of discontinuing thyroid hormone treatment earlier than recommended by the current guidelines for congenital hypothyroidism. METHODS We retrospectively reviewed the medical records of very low-birthweight (VLBW) infants born at Chungbuk National University Hospital from January 2006 to December 2010. Infants were divided into two groups--hypothyroid and normal thyroid--on the basis of the thyroid function test results. Infants in the hypothyroid group were treated with levothyroxine (L-T4) and attempts to discontinue this therapy began when they were about 2 years old. RESULTS Of the 216 infants born during the study period, 20 died and 196 were included in the study. Of these, 46 were in the hypothyroid group and 150 were in the normal thyroid group. Thirty-nine infants were taken off L-T4 therapy at around 2 years of age. All were successfully weaned off L-T4 and retained normal thyroid function. Tc-99 m thyroid scans were performed in 32 infants, and no distinct abnormality was noted. CONCLUSION Thyroid dysfunction in VLBW infants was common in our cohort and most cases were transient. Attempts to discontinue this therapy could begin at around the age of two or earlier when low doses of L-T4 have achieved maintenance.
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Affiliation(s)
- Gina Lim
- Department of Pediatrics; Ulsan University Hospital; University of Ulsan College of Medicine; Ulsan Korea
| | - Youn Kyung Lee
- Department of Pediatrics; Chungbuk National University Hospital; Cheongju Korea
| | - Heon-Seok Han
- Department of Pediatrics; Chungbuk National University Hospital; Cheongju Korea
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87
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Portulano C, Paroder-Belenitsky M, Carrasco N. The Na+/I- symporter (NIS): mechanism and medical impact. Endocr Rev 2014; 35:106-49. [PMID: 24311738 PMCID: PMC3895864 DOI: 10.1210/er.2012-1036] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 10/11/2013] [Indexed: 12/26/2022]
Abstract
The Na(+)/I(-) symporter (NIS) is the plasma membrane glycoprotein that mediates active I(-) transport in the thyroid and other tissues, such as salivary glands, stomach, lactating breast, and small intestine. In the thyroid, NIS-mediated I(-) uptake plays a key role as the first step in the biosynthesis of the thyroid hormones, of which iodine is an essential constituent. These hormones are crucial for the development of the central nervous system and the lungs in the fetus and the newborn and for intermediary metabolism at all ages. Since the cloning of NIS in 1996, NIS research has become a major field of inquiry, with considerable impact on many basic and translational areas. In this article, we review the most recent findings on NIS, I(-) homeostasis, and related topics and place them in historical context. Among many other issues, we discuss the current outlook on iodide deficiency disorders, the present stage of understanding of the structure/function properties of NIS, information gleaned from the characterization of I(-) transport deficiency-causing NIS mutations, insights derived from the newly reported crystal structures of prokaryotic transporters and 3-dimensional homology modeling, and the novel discovery that NIS transports different substrates with different stoichiometries. A review of NIS regulatory mechanisms is provided, including a newly discovered one involving a K(+) channel that is required for NIS function in the thyroid. We also cover current and potential clinical applications of NIS, such as its central role in the treatment of thyroid cancer, its promising use as a reporter gene in imaging and diagnostic procedures, and the latest studies on NIS gene transfer aimed at extending radioiodide treatment to extrathyroidal cancers, including those involving specially engineered NIS molecules.
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Affiliation(s)
- Carla Portulano
- Department of Molecular and Cellular Physiology (C.P., N.C.), Yale University School of Medicine, New Haven, Connecticut 06510; and Department of Molecular Pharmacology (M.P.-B.), Albert Einstein College of Medicine, Bronx, New York 10469
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88
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Grey matter abnormalities in untreated hyperthyroidism: A voxel-based morphometry study using the DARTEL approach. Eur J Radiol 2014; 83:e43-8. [PMID: 24161779 DOI: 10.1016/j.ejrad.2013.09.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/15/2013] [Accepted: 09/22/2013] [Indexed: 11/24/2022]
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89
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Tonyushkina KN, Shen MC, Ortiz-Toro T, Karlstrom RO. Embryonic exposure to excess thyroid hormone causes thyrotrope cell death. J Clin Invest 2014; 124:321-7. [PMID: 24316972 PMCID: PMC3871235 DOI: 10.1172/jci70038] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/27/2013] [Indexed: 11/17/2022] Open
Abstract
Central congenital hypothyroidism (CCH) is more prevalent in children born to women with hyperthyroidism during pregnancy, suggesting a role for thyroid hormone (TH) in the development of central thyroid regulation. Using the zebrafish embryo as a model for thyroid axis development, we have characterized the ontogeny of negative feedback regulation of thyrotrope function and examined the effect of excess TH on thyrotrope development. We found that thyroid-stimulating hormone β subunit (tshb) and type 2 deiodinase (dio2) are coexpressed in zebrafish thyrotropes by 48 hours after fertilization and that TH-driven negative feedback regulation of tshb transcription appears in the thyroid axis by 96 hours after fertilization. Negative feedback regulation correlated with increased systemic TH levels from the developing thyroid follicles. We used a transgenic zebrafish that expresses GFP under the control of the tshb promoter to follow thyrotrope fates in vivo. Time-lapse imaging revealed that early exposure to elevated TH leads to thyrotrope cell death. Thyrotrope numbers slowly recovered following the removal of excess TH. These data demonstrate that transient TH exposure profoundly impacts the thyrotrope population during a critical period of pituitary development and may have long-term implications for the functional reserve of thyroid-stimulating hormone (TSH) production and the TSH set point later in life.
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Affiliation(s)
- Ksenia N. Tonyushkina
- Department of Pediatrics, Baystate Medical Center, Springfield, Massachusetts, USA.
Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Meng-Chieh Shen
- Department of Pediatrics, Baystate Medical Center, Springfield, Massachusetts, USA.
Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Theresa Ortiz-Toro
- Department of Pediatrics, Baystate Medical Center, Springfield, Massachusetts, USA.
Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Rolf O. Karlstrom
- Department of Pediatrics, Baystate Medical Center, Springfield, Massachusetts, USA.
Department of Biology, University of Massachusetts, Amherst, Massachusetts, USA
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90
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de Vries GJ, Fields CT, Peters NV, Whylings J, Paul MJ. Sensitive periods for hormonal programming of the brain. Curr Top Behav Neurosci 2014; 16:79-108. [PMID: 24549723 DOI: 10.1007/7854_2014_286] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
During sensitive periods, information from the external and internal environment that occurs during particular phases of development is relayed to the brain to program neural development. Hormones play a central role in this process. In this review, we first discuss sexual differentiation of the brain as an example of hormonal programming. Using sexual differentiation, we define sensitive periods, review cellular and molecular processes that can explain their restricted temporal window, and discuss challenges in determining the precise timing of the temporal window. We then briefly review programming effects of other hormonal systems and discuss how programming of these systems interact with sexual differentiation.
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Affiliation(s)
- Geert J de Vries
- Neuroscience Institute, Georgia State University, PO Box 5030, Atlanta, GA, 30302-5030, USA,
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91
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92
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Treatment with thyroxine restores myelination and clinical recovery after intraventricular hemorrhage. J Neurosci 2013; 33:17232-46. [PMID: 24174657 DOI: 10.1523/jneurosci.2713-13.2013] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Intraventricular hemorrhage (IVH) remains a major cause of white matter injury in preterm infants with no viable therapeutic strategy to restore myelination. Maturation of oligodendrocytes and myelination is influenced by thyroid hormone (TH) signaling, which is mediated by TH receptor α (TRα) and TRβ. In the brain, cellular levels of TH are regulated by deiodinases, with deiodinase-2 mediating TH activation and deiodinase-3 TH inactivation. Therefore, we hypothesized that IVH would decrease TH signaling via changes in the expression of deiodinases and/or TRs, and normalization of TH signaling would enhance maturation of oligodendrocytes and myelination in preterm infants with IVH. These hypotheses were tested using both autopsy materials from human preterm infants and a rabbit model of IVH. We found that deiodinase-2 levels were reduced, whereas deiodinase-3 levels were increased in brain samples of both humans and rabbits with IVH compared with controls without IVH. TRα expression was also increased in human infants with IVH. Importantly, treatment with TH accelerated the proliferation and maturation of oligodendrocytes, increased transcription of Olig2 and Sox10 genes, augmented myelination, and restored neurological function in pups with IVH. Consistent with these findings, the density of myelinating oligodendrocytes was almost doubled in TH-treated human preterm infants compared with controls. Thus, in infants with IVH the combined elevation in deiodinase-3 and reduction in deiodinase-2 decreases TH signaling that can be worsened by an increase in unliganded TRα. Given that TH promotes neurological recovery in IVH, TH treatment might improve the neurodevelopmental outcome of preterm infants with IVH.
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93
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Mohr R, Neckel P, Zhang Y, Stachon S, Nothelfer K, Schaeferhoff K, Obermayr F, Bonin M, Just L. Molecular and cell biological effects of 3,5,3′-triiodothyronine on progenitor cells of the enteric nervous system in vitro. Stem Cell Res 2013; 11:1191-205. [DOI: 10.1016/j.scr.2013.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 07/15/2013] [Accepted: 08/01/2013] [Indexed: 01/18/2023] Open
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Van Herck SLJ, Geysens S, Delbaere J, Darras VM. Regulators of thyroid hormone availability and action in embryonic chicken brain development. Gen Comp Endocrinol 2013; 190:96-104. [PMID: 23707378 DOI: 10.1016/j.ygcen.2013.05.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 11/21/2022]
Abstract
Thyroid hormones (THs) are crucial elements in vertebrate brain development. They exert their action mainly through binding of 3,5,3'-triiodothyronine (T3) to nuclear receptors that directly influence the expression of TH-regulated genes. Intracellular TH action is therefore dependent on both the availability of T3 and its receptors. TH uptake in cells is regulated by specific TH transporters and local activation and inactivation is regulated by deiodinases. This review provides an overview of the general expression pattern of TH transporters, deiodinases and receptors during embryonic chicken brain development and compares it to the situation in mammals. It is clear that THs and their regulators are present in the embryonic brain from the early stages of development, long before the onset of embryonic thyroid gland functioning. The mechanism of TH uptake across the brain barriers during development is only partly understood. At the developing blood-brain-barrier expression of the TH-activating type 2 deiodinase is closely associated with the blood vessels, but contrary to the situation in (adult) mammals no expression of MCT8 or OATP1C1 TH transporters is found at that level in the developing chicken. At the blood-cerebrospinal fluid-barrier co-expression of the TH-inactivating type 3 deiodinase and MCT8 and OATP1C1 is found in birds and mammals. These comparative data show overlapping patterns, pointing to general mechanisms, but also indicate specific interspecies differences that may help to understand species-specific responses to regulator gene knockout/mutation.
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Affiliation(s)
- Stijn L J Van Herck
- Laboratory of Comparative Endocrinology, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, B-3000 Leuven, Belgium.
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95
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Neurodevelopment of children assessed after prenatal exposure to polybrominated diethyl ethers from collapse of world trade center. Ther Drug Monit 2013; 35:560-1. [PMID: 23942541 DOI: 10.1097/ftd.0b013e318292b7ee] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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96
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Storaci V, Eblen-Zajjur A. Nongenomic effect of levothyroxine on the synchronous electrical activity of the spinal dorsal horn in the rat. Somatosens Mot Res 2013; 31:23-7. [PMID: 23919349 DOI: 10.3109/08990220.2013.819798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Levothyroxine (T4) has a well-known effect on the central nervous system (CNS). This effect requires hours of latency by genetic pathway. We tested for short latency nongenomic effects of T4 superfusion on the spinal dorsal horn (DH) evaluating lumbar somatosensory evoked potentials in rats. T4 increased N and P wave amplitudes and N wave area under the curve, but reduced P wave duration and N-P interval, suggesting that T4 exerts both excitatory and synchronizing effects on DH interneurons in less than 300 s, thus, providing evidence of nongenomic effects of T4 on DH.
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Affiliation(s)
- Verónika Storaci
- Dpto. de Biología, Facultad de Ciencias y Tecnología, Universidad de Carabobo , Valencia , Venezuela
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97
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Wu YJ, Xu MY, Wang L, Sun BL, Gu GX. Analysis of EphA5 receptor in the developing rat brain: an in vivo study in congenital hypothyroidism model. Eur J Pediatr 2013; 172:1077-83. [PMID: 23636281 DOI: 10.1007/s00431-013-2008-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/16/2013] [Indexed: 12/24/2022]
Abstract
UNLABELLED The EphA5 receptor has recently been known to play an important role in the initiation of the early phase of synaptogenesis, during which irreparable harm would be done to the developing brain in the absence of sufficient thyroid hormone (TH). In the present article, we aimed to analyze the characteristics of EphA5 receptor expression in the brain of congenital hypothyroid rats. The results showed that the levels of the EphA5 receptor were downregulated by TH deficiency in the developing rat brain with remarkable spatial and temporal characteristics. In the hypothyroid rats, the mRNA and protein levels of EphA5 receptor decreased significantly in the hippocampus (27.92-53.26%), cerebral cortex (12.52-47.16%), and cerebellum (8.72-31.69%) compared with those in the normal rats from postnatal day 0 (P0) to P21 (p < 0.01). The expression of EphA5 receptor was highest and declined most as much as 53% in the hippocampus with TH deficiency. At P7, the EphA5 receptor decreased most prominently during all the observed time point. CONCLUSION The EphA5 receptor plays actively in the brain development in congenital hypothyroid rats. Our study highlights the high expression of EphA5 receptor protein in hippocampus and dramatic changes at P7 in condition of TH deficiency, which may provide important basis for further investigations in manipulating congenital hypothyroidism.
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Affiliation(s)
- You-jia Wu
- Department of Pediatric Healthcare, Children's Hospital of Soochow University, 303 Jingde Road, Suzhou 215003, Jiangsu Province, China
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98
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Stenzel D, Huttner WB. Role of maternal thyroid hormones in the developing neocortex and during human evolution. Front Neuroanat 2013; 7:19. [PMID: 23882187 PMCID: PMC3712268 DOI: 10.3389/fnana.2013.00019] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 06/04/2013] [Indexed: 01/30/2023] Open
Abstract
The importance of thyroid hormones during brain development has been appreciated for many decades. In humans, low levels of circulating maternal thyroid hormones, e.g., caused by maternal hypothyroidism or lack of iodine in diet, results in a wide spectrum of severe neurological defects, including neurological cretinism characterized by profound neurologic impairment and mental retardation, underlining the importance of the maternal thyroid hormone contribution. In fact, iodine intake, which is essential for thyroid hormone production in the thyroid gland, has been related to the expansion of the brain, associated with the increased cognitive capacities during human evolution. Because thyroid hormones regulate transcriptional activity of target genes via their nuclear thyroid hormone receptors (THRs), even mild and transient changes in maternal thyroid hormone levels can directly affect and alter the gene expression profile, and thus disturb fetal brain development. Here we summarize how thyroid hormones may have influenced human brain evolution through the adaptation to new habitats, concomitant with changes in diet and, therefore, iodine intake. Further, we review the current picture we gained from experimental studies in rodents on the function of maternal thyroid hormones during developmental neurogenesis. We aim to evaluate the effects of maternal thyroid hormone deficiency as well as lack of THRs and transporters on brain development and function, shedding light on the cellular behavior conducted by thyroid hormones.
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Affiliation(s)
- Denise Stenzel
- Max Planck Institute of Molecular Biology and Genetics Dresden, Germany
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99
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Korzeniewski SJ, Kleyn M, Young WI, Chaiworapongsa T, Schwartz AG, Romero R. Screening for congenital hypothyroidism in newborns transferred to neonatal intensive care. Arch Dis Child Fetal Neonatal Ed 2013; 98. [PMID: 23183553 PMCID: PMC4136805 DOI: 10.1136/archdischild-2012-302192] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate the effectiveness of four dried blood spot testing protocols used in newborn screening for congenital hypothyroidism (CH) among newborns transferred to the neonatal intensive care unit (NICU). DESIGN, SETTING AND PATIENTS Michigan newborns transferred to the NICU from 1998 to 2011 and screened for CH are included in this population-based retrospective cohort study. MAIN OUTCOME MEASURES Screening performance metrics are computed and logistic regression is used to test for differences in the likelihood of detection across four periods characterised by different testing protocols. RESULTS Primary thyrotropin (TSH) plus retest at 30 days of life or discharge achieved the greatest detection rate (2.6: 1000 births screened). The odds of detection was also significantly greater in this period compared with the tandem thyroxine (T4) and TSH testing period and separately compared with TSH testing alone, adjusted for birth weight, sex and race (OR 1.5; CI 1.0 to 2.2; p=0.046, and OR 2.2; CI 1.5 to 3.4, respectively). Approximately half of the cases detected during primary TSH plus serial testing periods were identified by retest. CONCLUSIONS Primary TSH testing programmes that do not incorporate serial screening may fail to identify approximately half of newborns with congenital thyroid hormone deficiency transferred to the NICU. Tandem T4 and TSH testing programmes also likely miss cases who otherwise would receive treatment if serial testing were conducted. Further research is necessary to determine the optimal newborn screening protocol for CH; strategies combining tandem T4 and TSH with serial testing conditional on birthweight may be useful.
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Affiliation(s)
- Steven J. Korzeniewski
- Perinatology Research Branch, NICHD/NIH/DHHS, Detroit, MI, USA,Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA,Corresponding Author: Steven J. Korzeniewski, Director, Perinatal Epidemiology Unit, Perinatology Research Branch, NICHD/NIH/DHHS, Assistant Professor, Department of Obstetrics & Gynecology, Wayne State University School of Medicine, Hutzel Women's Hospital, 4 Brush - Office 4817, 3990 John R. - Detroit, MI 48201, P 313.577.0364~ F 313.577.5242,
| | - Mary Kleyn
- Michigan Department of Community Health, Lansing, MI, USA
| | | | - Tinnakorn Chaiworapongsa
- Perinatology Research Branch, NICHD/NIH/DHHS, Detroit, MI, USA,Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA
| | | | - Roberto Romero
- Perinatology Research Branch, NICHD/NIH/DHHS, Detroit, MI, USA
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Dong W, Macaulay L, Kwok KWH, Hinton DE, Stapleton HM. Using whole mount in situ hybridization to examine thyroid hormone deiodinase expression in embryonic and larval zebrafish: a tool for examining OH-BDE toxicity to early life stages. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2013; 132-133:190-9. [PMID: 23531416 PMCID: PMC3642849 DOI: 10.1016/j.aquatox.2013.02.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 02/11/2013] [Accepted: 02/13/2013] [Indexed: 05/20/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) and their oxidative metabolites (hydroxylated PBDEs; OH-BDEs) are known endocrine disrupting contaminants that have been shown to disrupt thyroid hormone regulation both in mammals and in fish. The purpose of this study was to determine the precise organ and tissue locations that express genes critical to thyroid hormone regulation in developing zebrafish (Danio rerio), and to determine the effects of an OH-BDE on their expression. While RT-PCR can provide quantitative data on gene expression, it lacks spatial sensitivity to examine localized gene expression; and, isolation of organs from zebrafish embryos is technically difficult, if not impossible. For this reason, the present study used whole mount in situ hybridization to simultaneously localize and quantify gene expression in vivo. While PBDEs and OH-BDEs have been shown to inhibit the activity and expression of deiodionases, a family of enzymes that regulate thyroid hormone concentrations intracellularly, it is unclear whether or not they can affect regional expression of the different isoforms during early development. In this study we investigated deiodinase 1 (Dio1), deiodinase 2 (Dio2), and deiodinase 3 (Dio3) mRNA expression at the following life stages (2, 8, and 1k-cells; 50%-epiboly, 6 and 18-somites, 22, 24, 48, 72 hpf and/or 10 dpf) in zebrafish and found life stage specific expression of these genes that were highly localized. To demonstrate the use of this technique for investigating potential endocrine disrupting effects, zebrafish embryos were exposed to 1, 10 and 100nM 6-OH-BDE-47. Significant increases in mean intensity of Dio1 and Dio3 expression in the periventricular zone of brain and pronephric duct, respectively (quantified by measuring intensity of coloration using ImageJ analysis software) were observed, suggesting localized response at the HPT axis with the possibility of impacting neurodevelopment. Our results demonstrate effects of OH-BDEs on thyroid regulating gene expression and provide more insight into potential sites of injury during early life stages.
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Affiliation(s)
- Wu Dong
- To whom correspondence should be addressed. Heather Stapleton, Phone: 919-613-8717, Fax: (919) 684-8741.
| | | | | | | | - Heather M. Stapleton
- To whom correspondence should be addressed. Heather Stapleton, Phone: 919-613-8717, Fax: (919) 684-8741.
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