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Sabatino L, Lapi D, Del Seppia C. Factors and Mechanisms of Thyroid Hormone Activity in the Brain: Possible Role in Recovery and Protection. Biomolecules 2024; 14:198. [PMID: 38397435 PMCID: PMC10886502 DOI: 10.3390/biom14020198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/29/2024] [Accepted: 02/03/2024] [Indexed: 02/25/2024] Open
Abstract
Thyroid hormones (THs) are essential in normal brain development, and cognitive and emotional functions. THs act through a cascade of events including uptake by the target cells by specific cell membrane transporters, activation or inactivation by deiodinase enzymes, and interaction with nuclear thyroid hormone receptors. Several thyroid responsive genes have been described in the developing and in the adult brain and many studies have demonstrated a systemic or local reduction in TH availability in neurologic disease and after brain injury. In this review, the main factors and mechanisms associated with the THs in the normal and damaged brain will be evaluated in different regions and cellular contexts. Furthermore, the most common animal models used to study the role of THs in brain damage and cognitive impairment will be described and the use of THs as a potential recovery strategy from neuropathological conditions will be evaluated. Finally, particular attention will be given to the link observed between TH alterations and increased risk of Alzheimer's Disease (AD), the most prevalent neurodegenerative and dementing condition worldwide.
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Affiliation(s)
- Laura Sabatino
- Institute of Clinical Physiology, National Council of Research, Via Moruzzi 1, 56124 Pisa, Italy;
| | - Dominga Lapi
- Department of Biology, University of Pisa, 56127 Pisa, Italy;
| | - Cristina Del Seppia
- Institute of Clinical Physiology, National Council of Research, Via Moruzzi 1, 56124 Pisa, Italy;
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2
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Alcaide Martin A, Mayerl S. Local Thyroid Hormone Action in Brain Development. Int J Mol Sci 2023; 24:12352. [PMID: 37569727 PMCID: PMC10418487 DOI: 10.3390/ijms241512352] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/28/2023] [Accepted: 07/30/2023] [Indexed: 08/13/2023] Open
Abstract
Proper brain development essentially depends on the timed availability of sufficient amounts of thyroid hormone (TH). This, in turn, necessitates a tightly regulated expression of TH signaling components such as TH transporters, deiodinases, and TH receptors in a brain region- and cell-specific manner from early developmental stages onwards. Abnormal TH levels during critical stages, as well as mutations in TH signaling components that alter the global and/or local thyroidal state, result in detrimental consequences for brain development and neurological functions that involve alterations in central neurotransmitter systems. Thus, the question as to how TH signaling is implicated in the development and maturation of different neurotransmitter and neuromodulator systems has gained increasing attention. In this review, we first summarize the current knowledge on the regulation of TH signaling components during brain development. We then present recent advances in our understanding on how altered TH signaling compromises the development of cortical glutamatergic neurons, inhibitory GABAergic interneurons, cholinergic and dopaminergic neurons. Thereby, we highlight novel mechanistic insights and point out open questions in this evolving research field.
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Affiliation(s)
| | - Steffen Mayerl
- Department of Endocrinology Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, Hufelandstraße 55, 45147 Essen, Germany
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3
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Temporal control of neuronal wiring. Semin Cell Dev Biol 2023; 142:81-90. [PMID: 35644877 DOI: 10.1016/j.semcdb.2022.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/13/2022] [Accepted: 05/16/2022] [Indexed: 12/22/2022]
Abstract
Wiring an animal brain is a complex process involving a staggering number of cell-types born at different times and locations in the developing brain. Incorporation of these cells into precise circuits with high fidelity is critical for animal survival and behavior. Assembly of neuronal circuits is heavily dependent upon proper timing of wiring programs, requiring neurons to express specific sets of genes (sometimes transiently) at the right time in development. While cell-type specificity of genetic programs regulating wiring has been studied in detail, mechanisms regulating proper timing and coordination of these programs across cell-types are only just beginning to emerge. In this review, we discuss some temporal regulators of wiring programs and how their activity is controlled over time and space. A common feature emerges from these temporal regulators - they are induced by cell-extrinsic cues and control transcription factors capable of regulating a highly cell-type specific set of target genes. Target specificity in these contexts comes from cell-type specific transcription factors. We propose that the spatiotemporal specificity of wiring programs is controlled by the combinatorial activity of temporal programs and cell-type specific transcription factors. Going forward, a better understanding of temporal regulators will be key to understanding the mechanisms underlying brain wiring, and will be critical for the development of in vitro models like brain organoids.
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Liu M, Yu Z, Zhao Z, Yang F, Zhou M, Wang C, Tian X, Zhang B, Liang G, Liu X, Shao J. MiR-24-3p/Dio3 axis is essential for BDE47 to induce local thyroid hormone disorder and neurotoxicity. Toxicology 2023; 491:153527. [PMID: 37116683 DOI: 10.1016/j.tox.2023.153527] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 04/30/2023]
Abstract
BDE47 (2,2,4,4-tetrabromodiphenyl ether) is a member of the most important congeners of polybrominated diphenyl ethers (PBDEs) and has been identified as a developmental, reproductive and nervous system toxicant and endocrine system disruptor due to its frequent detection in human tissue and environmental samples. Our preliminary work suggested that high- and low-level of bromodiphenyl ethers have different effects on neuronal cells with differential targets of actions on neural tissues. In this study, we presented the underlying mechanism of BDE47 neurotoxicity from the perspective of thyroid hormone (TH) metabolism using in vitro model of human SK-N-AS neuronal cells. BDE47 could induce local TH metabolism disorder in neuronal cells by inhibiting the expression of the main enzyme, human type III iodothyronine deiodinase (Dio3). Further elucidation revealed that BDE47 effectively up-regulating miR-24-3p, which binds to the 3'-UTR of Dio3 and inhibits its expression. In addition, BDE47 could also inhibit the deiodinase activity of Dio3. Collectively, our study demonstrates the molecular mechanism of BDE47 regulating Dio3-induced TH metabolism disorder through inducing miR-24-3p, providing new clues for the role of miRNAs in neurodevelopmental toxicity mediated by environmental pollutants.
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Affiliation(s)
- Min Liu
- Department of Environmental Health and Toxicology, School of Public Health, Dalian Medical University, Dalian, 116044, China; Neurology Department, Dalian University Affiliated Xinhua Hospital, Dalian, 116021, China
| | - Zhenlong Yu
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
| | - Zikuang Zhao
- School of Pharmacy, Hangzhou Normal University, Hangzhou, 116000, China
| | - Fangyu Yang
- General Hospital of Northern Theater Command (General Hospital of Shenyang Military Command), Department of Neurosurgery, Shenyang, China
| | - Meirong Zhou
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
| | - Chao Wang
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
| | - Xiangge Tian
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
| | - Baojing Zhang
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
| | - Guobiao Liang
- General Hospital of Northern Theater Command (General Hospital of Shenyang Military Command), Department of Neurosurgery, Shenyang, China.
| | - Xiaohui Liu
- Department of Environmental Health and Toxicology, School of Public Health, Dalian Medical University, Dalian, 116044, China
| | - Jing Shao
- Department of Environmental Health and Toxicology, School of Public Health, Dalian Medical University, Dalian, 116044, China; Liaoning Key Laboratory of Hematopoietic Stem Cell Transplantation and Translational Medicine; Liaoning Medical Center for Hematopoietic Stem Cell Transplantation; Dalian Key Laboratory of Hematology; Diamond Bay Institute of Hematology; Second Hospital of Dalian Medical University, Dalian, 116027, China.
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5
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Pathophysiology and Management Possibilities of Thyroid-Associated Depression. ACTA MEDICA BULGARICA 2022. [DOI: 10.2478/amb-2022-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Abstract
Thyroid hormones and the hypothalamic-pituitary-thyroid (HPA) axis are responsible for multiple metabolic processes and psychological well-being. Hypothyroidism can induce mood changes, depressive symptoms and even major depressive disorder. This review is focused on the pathophysiology and mechanisms through which the low level of thyroid hormones may affect the brain function, causing the characteristic symptoms of depression. Key pathways of hypothyroid-associated depressive states include: morphological changes in some brain areas (mainly in the hippocampus – a reduction in its volume); a significant reduction of the cerebral blood flow (incl. hippocampus), and lowered levels of neurotrophic factors (e. g. BDNF – brain-derived neurotrophic factor), which are regulated by the thyroid hormones. An adequate and timely thyroid hormone replacement and treatment with conventional antidepressants often can reverse the psychological symptoms.
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Mayerl S, Alcaide Martin A, Bauer R, Schwaninger M, Heuer H, ffrench-Constant C. Distinct Actions of the Thyroid Hormone Transporters Mct8 and Oatp1c1 in Murine Adult Hippocampal Neurogenesis. Cells 2022; 11:524. [PMID: 35159334 PMCID: PMC8834272 DOI: 10.3390/cells11030524] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/25/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Inactivating mutations in the thyroid hormone (TH) transporter monocarboxylate transporter 8 (MCT8) result in Allan-Herndon-Dudley Syndrome, a severe form of psychomotor retardation, while inactivating mutations in another TH transporter, organic anion transporting polypeptide 1c1 (OATP1C1), are linked to juvenile neurodegeneration. These diseases point to essential roles for TH transporters in CNS function. We recently defined the presence of Mct8 in adult hippocampal progenitors and mature granule cell neurons and unraveled cell-autonomous and indirect requirements for Mct8 in adult hippocampal neurogenesis. Here, we investigated whether Oatp1c1 is involved in the hippocampal neurogenic process in concert with Mct8. We detected Oatp1c1 gene expression activity and transcripts in subsets of progenitors, neurons and niche cells in the dentate gyrus. Absence of Oatp1c1 resulted in increased neuroblast and reduced immature neuron numbers in 6-month-old Oatp1c1ko and Mct8/Oatp1c1 double knockout (M/Odko) mice. Reduced EdU-label retention in Mct8ko and M/Odko mice confirmed the impact of Mct8 on neuron formation. In contrast, no significant effect of Oatp1c1 loss on granule cell neuron production and anxiety-like behavior in the open field arena were seen. Together, our results reinforce that distinct actions of each TH transporter are required at multiple stages to ensure proper adult hippocampal neurogenesis.
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Affiliation(s)
- Steffen Mayerl
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK;
| | - Andrea Alcaide Martin
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
| | - Reinhard Bauer
- Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany;
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, 23562 Lübeck, Germany;
| | - Heike Heuer
- Department of Endocrinology, Diabetes & Metabolism, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (A.A.M.); (H.H.)
| | - Charles ffrench-Constant
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK;
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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Das D, Banerjee A, Jena AB, Duttaroy AK, Pathak S. Essentiality, relevance, and efficacy of adjuvant/combinational therapy in the management of thyroid dysfunctions. Biomed Pharmacother 2022; 146:112613. [PMID: 35062076 DOI: 10.1016/j.biopha.2022.112613] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 12/14/2021] [Accepted: 01/02/2022] [Indexed: 11/02/2022] Open
Abstract
Thyroid dysfunction is the most prevalent endocrine disorder worldwide having an epidemiology of 11% in Indians, 4.6% in the United Kingdom, and 2% in the United States of America among the overall population. The common thyroid disorders include hypothyroidism, hyperthyroidism, Hashimoto's thyroiditis, and thyroid cancer. This review briefly elaborates the molecular regulation and mechanism of thyroid hormone, and its associated thyroid disorders. The thyroid hormones regulate critical biochemical functions in brain development and function. Hypothyroidism is mainly associated with dysregulation of cytokines, increased ROS production, and altered signal transduction in major regions of the brain. In addition, it is associated with reduced antioxidant capacity and increased oxidative stress in humans. Though 70% of thyroid disorders are caused by heredity, environmental factors have a significant influence in developing autoimmune thyroid disorders in people who are predisposed to them. This drives us to understand the relationship between environmental factors and thyroid dysregulated disorders. The treatment option for the thyroid disorder includes antithyroid medications, receiving radioactive iodine therapy, or surgery at a critical stage. However, antithyroid drugs are not typically used long-term in thyroid disease due to the high recurrence rate. Adjuvant treatment of antioxidants can produce better outcomes with anti-thyroid drug treatment. Thus, Adjuvant therapy has been proven as an effective strategy for managing thyroid dysfunction, herbal remedies can be used to treat thyroid dysfunction in the future, which in turn can reduce the prevalence of thyroid disorders.
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Affiliation(s)
- Diptimayee Das
- Faculty of Allied Health Sciences, Chettinad Academy of Research and Education (CARE), Chettinad Hospital and Research Institute (CHRI), Chennai 603103, India
| | - Antara Banerjee
- Department of Medical Biotechnology, Faculty of Allied Health Sciences, Chettinad Academy of Research and Education (CARE), Chettinad Hospital and Research Institute (CHRI), Chennai, India
| | | | - Asim K Duttaroy
- Department of Nutrition, Institute of Medical Sciences, Faculty of Medicine, University of Oslo, Norway.
| | - Surajit Pathak
- Department of Medical Biotechnology, Faculty of Allied Health Sciences, Chettinad Academy of Research and Education (CARE), Chettinad Hospital and Research Institute (CHRI), Chennai, India.
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8
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Qin C, Cheng Y, Shang X, Wang R, Wang R, Hao X, Li S, Wang Y, Li Y, Liu X, Shao J. Disturbance of the Dlk1-Dio3 imprinted domain may underlie placental Dio3 suppression and extracellular thyroid hormone disturbance in placenta-derived JEG-3 cells following decabromodiphenyl ether (BDE209) exposure. Toxicology 2021; 458:152837. [PMID: 34166751 DOI: 10.1016/j.tox.2021.152837] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/29/2021] [Accepted: 06/16/2021] [Indexed: 10/21/2022]
Abstract
Decabromodiphenyl ether (BDE209) has been widely used as a flame retardant in the past four decades, leading to human health consequences, especially neurological impairments. Our previous in vivo studies have suggested that developmental neurotoxicity in offspring may be the result of BDE209-induced placental type III iodothyronine deiodinase (Dio3) disturbance and consequent thyroid hormone (TH) instability. Dio3 is paternally imprinted gene, and its balanced expression is crucial in directing normal development and growth. In this study, we used placenta-derived cells to investigate how BDE209 affected Dio3 expression through interfering imprinting mechanisms in the delta-like homolog 1 (Dlk1)-Dio3 imprinted region. Gene chip analysis and RT-qPCR identified miR409-3p, miR410-5p, miR494-3p, miR668-3p and miR889-5p as potential candidates involved in Dio3 deregulation. The sodium bisulfite-clonal sequencing revealed the BDE209 affect methylation status of two differentially methylated regions (DMRs), intergenic-DMR (IG-DMR) and maternally expressed gene 3-DMR (MEG3-DMR). Our data indicate that placental Dio3 may be a potential molecular target for future study of BDE209 developmental toxicity. In particular, miRNAs, IG-DMR and MEG3-DMR in the Dlk1-Dio3 imprinted locus may be informative in directing studies in TH disturbance and developmental toxicity induced by in utero exposure to environmental persistent organic pollutants (POPs), and those candidate miRNAs may prove to be convenient and noninvasive biomarkers for future large-scale population studies.
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Affiliation(s)
- Chang Qin
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Ying Cheng
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China; Zhongshan College of Dalian Medical University, Dalian, 116085, China
| | - Xiaona Shang
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Ruijun Wang
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Ruonan Wang
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Xiaoji Hao
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Sisi Li
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Ye Wang
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Yachen Li
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China
| | - Xiaohui Liu
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China.
| | - Jing Shao
- School of Public Health, Department of Occupational and Environmental Health Sciences, Dalian Medical University, Dalian, 116044, China; Liaoning Key Laboratory of Hematopoietic Stem Cell Transplantation and Translational Medicine, Liaoning Medical Center for Hematopoietic Stem Cell Transplantation, Dalian Key Laboratory of Hematology, Diamond Bay Institute of Hematology, Second Hospital of Dalian Medical University, Dalian, Liaoning, 116027, China.
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Congenital hypothyroidism impairs spine growth of dentate granule cells by downregulation of CaMKIV. Cell Death Discov 2021; 7:143. [PMID: 34127648 PMCID: PMC8203692 DOI: 10.1038/s41420-021-00530-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/23/2021] [Indexed: 12/13/2022] Open
Abstract
Congenital hypothyroidism (CH), a common neonatal endocrine disorder, can result in cognitive deficits if delay in diagnose and treatment. Dentate gyrus (DG) is the severely affected subregion of the hippocampus by the CH, where the dentate granule cells (DGCs) reside in. However, how CH impairs the cognitive function via affecting DGCs and the underlying mechanisms are not fully elucidated. In the present study, the CH model of rat pups was successfully established, and the aberrant dendrite growth of the DGCs and the impaired cognitive behaviors were observed in the offspring. Transcriptome analysis of hippocampal tissues following rat CH successfully identified that calcium/calmodulin-dependent protein kinase IV (CaMKIV) was the prominent regulator involved in mediating deficient growth of DGC dendrites. CaMKIV was shown to be dynamically regulated in the DG subregion of the rats following drug-induced CH. Interference of CaMKIV expression in the primary DGCs significantly reduced the spine density of dendrites, while addition of T3 to the primary DGCs isolated from CH pups could facilitate the spine growth of dendrites. Insights into relevant mechanisms revealed that CH-mediated CaMKIV deficiency resulted in the significant decrease of phosphorylated CREB in DGCs, in association with the abnormality of dendrites. Our results have provided a distinct cell type in hippocampus that is affected by CH, which would be beneficial for the treatment of CH-induced cognitive deficiency.
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Abstract
Thyroid hormone is essential for brain development and brain function in the adult. During development, thyroid hormone acts in a spatial and temporal-specific manner to regulate the expression of genes essential for normal neural cell differentiation, migration, and myelination. In the adult brain, thyroid hormone is important for maintaining normal brain function. Thyroid hormone excess, hyperthyroidism, and thyroid hormone deficiency, hypothyroidism, are associated with disordered brain function, including depression, memory loss, impaired cognitive function, irritability, and anxiety. Adequate thyroid hormone levels are required for normal brain function. Thyroid hormone acts through a cascade of signaling components: activation and inactivation by deiodinase enzymes, thyroid hormone membrane transporters, and nuclear thyroid hormone receptors. Additionally, the hypothalamic-pituitary-thyroid axis, with negative feedback of thyroid hormone on thyrotropin-releasing hormone (TRH) and thyroid-stimulating hormone (TSH) secretion, regulates serum thyroid hormone levels in a narrow range. Animal and human studies have shown both systemic and local reduction in thyroid hormone availability in neurologic disease and after brain trauma. Treatment with thyroid hormone and selective thyroid hormone analogs has resulted in a reduction in injury and improved recovery. This article will describe the thyroid hormone signal transduction pathway in the brain and the role of thyroid hormone in the aging brain, neurologic diseases, and the protective role when administered after traumatic brain injury. © 2021 American Physiological Society. Compr Physiol 11:1-21, 2021.
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Affiliation(s)
- Yan-Yun Liu
- Department of Medicine, VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Departments of Medicine and Physiology, Endocrinology, Diabetes and Metabolism Division, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Gregory A Brent
- Department of Medicine, VA Greater Los Angeles Healthcare System, Los Angeles, California, USA.,Departments of Medicine and Physiology, Endocrinology, Diabetes and Metabolism Division, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
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Camps T, Amat M, Manteca X. A Review of Medical Conditions and Behavioral Problems in Dogs and Cats. Animals (Basel) 2019; 9:E1133. [PMID: 31842492 PMCID: PMC6941081 DOI: 10.3390/ani9121133] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 12/11/2022] Open
Abstract
Not all animals behave identically when faced with the same situation. These individual differences in the expression of their behavior could be due to many factors, including medical conditions. These medical problems can change behavior directly or indirectly. The aims of this review are to describe the state of the art of the relationship among some medical and behavioral problems, and to propose new lines of investigation. The revision is focused on the relation between behavioral problems and pain, endocrine diseases, neurological problems, vomeronasal organ alterations, and cardiac disorders. These problems represent a diagnostic challenge from a practical point of view. The most common sign of pain in animals is a change in behavior. Although the relation of pain to behavioral problems has been widely studied, it is not absolutely clear. As an example, the relation between sleep disorders and pain is poorly known in veterinary medicine. New studies in humans and laboratory animals show that a reciprocal relationship does, in fact, exist. More specifically, the literature suggests that the temporal effect of sleep deprivation on pain may be stronger than that of pain on sleep. Some behavioral problems could modify the sleep-awake cycle (e.g., cognitive dysfunction). The impact of these behavioral problems on pain perception is completely unknown in dogs and cats. Thyroid hormones play an important role, regarding behavioral control. Both hypothyroidism and hyperthyroidism have been related to behavioral changes. Concerning hypothyroidism, this relationship remains controversial. Nonetheless, new neuro-imaging studies provide objective evidence that brain structure and function are altered in hypothyroid patients, both in laboratory animals and in humans. There are many neurological problems that could potentially change behavior. This paper reviews those neurological problems that could lead to behavioral changes without modifying neurological examination. The most common problems are tumors that affect central nervous system silent zones, mild traumatic brain injury, ischemic attacks, and epilepsy. Most of these diseases and their relationship to behavior are poorly studied in dogs and cats. To better understand the pathophysiology of all of these problems, and their relation to behavioral problems, may change the diagnostic protocol of behavioral problems.
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Affiliation(s)
- Tomàs Camps
- Etovets: Behavioral Medicine and Animal Welfare, 07010 Palma, Spain
| | - Marta Amat
- School of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; (M.A.); (X.M.)
| | - Xavier Manteca
- School of Veterinary Medicine, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; (M.A.); (X.M.)
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12
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Talhada D, Santos CRA, Gonçalves I, Ruscher K. Thyroid Hormones in the Brain and Their Impact in Recovery Mechanisms After Stroke. Front Neurol 2019; 10:1103. [PMID: 31681160 PMCID: PMC6814074 DOI: 10.3389/fneur.2019.01103] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/02/2019] [Indexed: 12/23/2022] Open
Abstract
Thyroid hormones are of fundamental importance for brain development and essential factors to warrant brain functions throughout life. Their actions are mediated by binding to specific intracellular and membranous receptors regulating genomic and non-genomic mechanisms in neurons and populations of glial cells, respectively. Among others, mechanisms include the regulation of neuronal plasticity processes, stimulation of angiogenesis and neurogenesis as well modulating the dynamics of cytoskeletal elements and intracellular transport processes. These mechanisms overlap with those that have been identified to enhance recovery of lost neurological functions during the first weeks and months after ischemic stroke. Stimulation of thyroid hormone signaling in the postischemic brain might be a promising therapeutic strategy to foster endogenous mechanisms of repair. Several studies have pointed to a significant association between thyroid hormones and outcome after stroke. With this review, we will provide an overview on functions of thyroid hormones in the healthy brain and summarize their mechanisms of action in the developing and adult brain. Also, we compile the major thyroid-modulated molecular pathways in the pathophysiology of ischemic stroke that can enhance recovery, highlighting thyroid hormones as a potential target for therapeutic intervention.
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Affiliation(s)
- Daniela Talhada
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- CICS-UBI-Health Sciences Research Centre, Faculdade de Ciências da Saúde, Universidade da Beira Interior, Covilha, Portugal
- LUBIN Lab-Lunds Laboratorium för Neurokirurgisk Hjärnskadeforskning, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Cecília Reis Alves Santos
- CICS-UBI-Health Sciences Research Centre, Faculdade de Ciências da Saúde, Universidade da Beira Interior, Covilha, Portugal
| | - Isabel Gonçalves
- CICS-UBI-Health Sciences Research Centre, Faculdade de Ciências da Saúde, Universidade da Beira Interior, Covilha, Portugal
| | - Karsten Ruscher
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- LUBIN Lab-Lunds Laboratorium för Neurokirurgisk Hjärnskadeforskning, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
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13
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Suo G, Shen F, Sun B, Song H, Xu M, Wu Y. Abnormal expression of ephrin-A5 affects brain development of congenital hypothyroidism rats. Neuroreport 2019; 29:877-882. [PMID: 29762250 DOI: 10.1097/wnr.0000000000001047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
EphA5 and its ligand ephrin-A5 interaction can trigger synaptogenesis during early hippocampus development. We have previously reported that abnormal EphA5 expression can result in synaptogenesis disorder in congenital hypothyroidism (CH) rats. To better understand its precise molecular mechanism, we further analyzed the characteristics of ephrin-A5 expression in the hippocampus of CH rats. Our study revealed that ephrin-A5 expression was downregulated by thyroid hormone deficiency in the developing hippocampus and hippocampal neurons in rats. Thyroxine treatment for hypothyroid hippocampus and triiodothyronine treatment for hypothyroid hippocampal neurons significantly improved ephrin-A5 expression but could not restore its expression to control levels. Hypothyroid hippocampal neurons in-vitro showed synaptogenesis disorder characterized by a reduction in the number and length of neurites. Furthermore, the synaptogenesis-associated molecular expressions of NMDAR-1 (NR1), PSD95 and CaMKII were all downregulated correspondingly. These results suggest that ephrin-A5 expression may be decreased in CH, and abnormal activation of ephrin-A5/EphA5 signaling affects synaptogenesis during brain development. Such findings provide an important basis for exploring the pathogenesis of CH genetically.
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Jarmołowska B, Bukało M, Fiedorowicz E, Cieślińska A, Kordulewska NK, Moszyńska M, Świątecki A, Kostyra E. Role of Milk-Derived Opioid Peptides and Proline Dipeptidyl Peptidase-4 in Autism Spectrum Disorders. Nutrients 2019; 11:nu11010087. [PMID: 30621149 PMCID: PMC6356206 DOI: 10.3390/nu11010087] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/11/2018] [Accepted: 12/28/2018] [Indexed: 01/08/2023] Open
Abstract
Opioid peptides released during digestion of dietary proteins such as casein, were suggested to contribute to autism development, leading to the announcement of opioid excess hypothesis of autism. This paper examines role of enzyme proline dipeptidyl peptidase-4 (DPPIV; EC 3.4.14.5) and it is exogenous substrate, β-casomorphin-7 (BCM7) in autism etiology. Our study included measurements of DPPIV and BCM7 concentrations in serum and urine, which were analyzed with ELISA assays and activity of DPPIV was measured by colorimetric test. The effect of opioid peptides from hydrolysed bovine milk on DPPIV gene expression in peripheral blood mononuclear cells (PBMC) in autistic and healthy children was determined using the Real-Time PCR (Polymerase Chain Reaction) method. Our research included 51 healthy children and 86 children diagnosed with autism spectrum disorder (ASD, ICDF84). We determined that the concentration of BCM7 in serum was significantly, 1.6-fold, higher in the ASD group than in controls (p < 0.0001). Concentration of DPPIV was found to also be significantly higher in serum from ASD children compared to the control group (p < 0.01), while we did not notice significant difference in enzymatic activity of serum DPPIV between the two study groups. We confirmed correlation according to the gender between analyzed parameters. The inspiration for this study emanated from clinical experience of the daily diet role in relieving the symptoms of autism. Despite this, we have concluded that milk-derived opioid peptides and DPPIV are potentially factors in determining the pathogenesis of autism; conducted studies are still limited and require further research.
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Affiliation(s)
- Beata Jarmołowska
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Marta Bukało
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Ewa Fiedorowicz
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Anna Cieślińska
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Natalia Karolina Kordulewska
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Małgorzata Moszyńska
- Center for Diagnosis, Treatment and Therapy of Autism at the Regional Children's Hospital in Olsztyn, Zolnierska 18 A Street, 10-561 Olsztyn, Poland.
| | - Aleksander Świątecki
- Faculty of Biology and Biotechnology, Department of Microbiology and Mycology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
| | - Elżbieta Kostyra
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Oczapowskiego 1A Street, 10-19 Olsztyn, Poland.
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Ferraris FK, Garcia EB, Chaves ADS, de Brito TM, Doro LH, Félix da Silva NM, Alves AS, Pádua TA, Henriques MDGMO, Cardoso Machado TS, Amendoeira FC. Exposure to the UV Filter Octyl Methoxy Cinnamate in the Postnatal Period Induces Thyroid Dysregulation and Perturbs the Immune System of Mice. Front Endocrinol (Lausanne) 2019; 10:943. [PMID: 32082254 PMCID: PMC7005579 DOI: 10.3389/fendo.2019.00943] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 12/31/2019] [Indexed: 02/05/2023] Open
Abstract
Evidence demonstrates the bidirectional communication and regulation between the neuroendocrine and immune systems. Thyroid hormones play key roles in nervous system development and can exert influence on various immune cells contributing to pathophysiological conditions. Octyl methoxycinnamate (OMC) is one of the most commonly used UV filters, and in vitro and in vivo studies have found thyroid disrupting effects. The present study assessed whether OMC administration in mice dams during the lactational period can cause thyroid disruption and generate immunologic alterations in the offspring. Indirect exposure to the OMC (1,000 mg/kg) in the lactational period affected neurodevelopment parameters, such as delayed eye-opening and weight gain in mice of both sexes, and these alterations are corroborated by the decrease in the T4 levels present in the pups' blood. No significant changes were observed in the thymus of these pups, but the number of lymphocytes increased in the spleen of the animals exposed to OMC, similar to the animals treated with propyl-thiouracil (PTU), a well-known thyroid disruptor. OMC modulated the percentage of leukocyte populations in peripheral blood, and the number of circulating polymorphonuclear cells increased two-fold. In vitro, OMC exhibited an inhibitory effect on splenocyte proliferation and IL-2 production induced by anti-CD3 antibody; however, this effect was reversed with the addition of T4 in the cell culture. In summary, the results of the present study demonstrate the influence of OMC on thyroid dysregulation and its impact on the modulation of the immune system in mice pups.
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Affiliation(s)
- Fausto Klabund Ferraris
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Esdras Barbosa Garcia
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Amanda da Silva Chaves
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Thais Morais de Brito
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Laís Higino Doro
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Naína Monsores Félix da Silva
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Amanda Soares Alves
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Tatiana Almeida Pádua
- Laboratory of Applied Pharmacology, Institute of Drug Technology (Far-Manguinhos)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Maria das Graças M. O. Henriques
- Laboratory of Applied Pharmacology, Institute of Drug Technology (Far-Manguinhos)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Tiago Savignon Cardoso Machado
- Laboratory of Professional Education in Laboratory Techniques in Health, Polytechnic School of Health Joaquim Venâncio—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Fabio Coelho Amendoeira
- Laboratory of Pharmacology, Department of Pharmacology and Toxicology, National Institute of Health Quality Control (INCQS)—Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
- *Correspondence: Fabio Coelho Amendoeira
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Cesur G, Eren MK, Eren E, Ergin K, Ek RO, Yıldız Y, Şirinyıldız F, Gök Balcı U, Ongel K. Effect of experimentally induced hypothyroidism during gestation period on activity dependent neurotrophic factor (ADNF) in newborn rat brain tissue. Horm Mol Biol Clin Investig 2018; 36:hmbci-2017-0069. [PMID: 30256757 DOI: 10.1515/hmbci-2017-0069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Accepted: 04/02/2018] [Indexed: 11/15/2022]
Abstract
Purpose The aim of the study was to evaluate the effects of prenatal hypothyroidism on neonatal rats by the way of activity-dependent neuroprotective factor (ADNF) expression. Methods Twenty-one Wistar albino neonatal rats were divided into two subgroups; a control group and neonatal rats with experimental maternal hypothyroidism. Hypothyroidism was induced by using propylthiouracil (PTU). Neonatal rats obtained PTU from breast milk continuously for 1 week after birth. The rats from the control group were fed only normal feed and water. After birth, body weight and blood thyroid hormone levels were tested. Glial fibrillary acidic protein (GFAP), Slug, Numb, Notch-1 and ADNF antibodies were used for immunohistochemical analysis. Real-time polymerase chain reaction (RT-PCR) and Western blotting analyses were used to evaluate ADNF gene expression levels from 1-week-old rat's brain. Results There was no difference between the two groups for birth weights. The thyroxine (T4) level from the experimental group was <0.4 ng/mL, and it was 0.8 ng/mL for the control group. It was shown that, the results from the experimental group samples had significantly lower ADNF mRNA levels than control group (p < 0.05). The increase from GFAP and Numb expression and decrease from Slug expression were shown in the experimental group. Local differences were identified for ADNF and a decrease was shown in both sides of brain. There was no difference for Notch-1 expression for both groups. Conclusion In this study, decreasing ADNF expression might contribute to developing neurological problems in congenital hypothyroidism.
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Affiliation(s)
- Gökhan Cesur
- Adnan Menderes University, Faculty of Medicine, Department of Physiology, Aydın, Turkey
| | - Mehtap Kılıç Eren
- Adnan Menderes University, Faculty of Medicine, Department of Medical Biology, Aydın, Turkey
| | - Erdal Eren
- Uludağ University, Faculty of Medicine, Department of Pediatric Endocrinology, Bursa, Turkey
| | - Kemal Ergin
- Adnan Menderes University, Faculty of Medicine, Department of Histology Embryology, Aydın, Turkey
| | - Rauf Onur Ek
- Adnan Menderes University, Faculty of Medicine, Department of Physiology, Aydın, Turkey
| | - Yüksel Yıldız
- Adnan Menderes University, Faculty of Medicine, Department of Physiology, Aydın, Turkey
| | - Ferhat Şirinyıldız
- Adnan Menderes University, Faculty of Medicine, Department of Physiology, Aydın, Turkey
| | - Umut Gök Balcı
- Tepecik Education and Research Hospital, Department of Family Medicine, Izmir, Turkey
| | - Kurtulus Ongel
- Izmir Katip Celebi University, Faculty of Medicine, Department of Family Medicine, Izmir, Turkey, Phone: +90.505.6487644
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Zhang F, Chen J, Lin X, Peng S, Yu X, Shan Z, Teng W. Subclinical hypothyroidism in pregnant rats impaired learning and memory of their offspring by promoting the p75 NTR signal pathway. Endocr Connect 2018; 7:688-697. [PMID: 29669804 PMCID: PMC5952246 DOI: 10.1530/ec-18-0069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 04/18/2018] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Maternal hypothyroidism during pregnancy can affect the neurodevelopment of their offspring. This study aimed to investigate the effects of maternal subclinical hypothyroidism (SCH) on spatial learning and memory, and its relationship with the apoptotic factors in cerebral cortex of the offspring. METHODS Female adult Wistar rats were randomly divided into three groups (n = 15 per group): control (CON) group, SCH group and overt hypothyroidism (OH) group. Spatial learning and memory in the offspring were evaluated by long-term potentiation (LTP) and Morris water-maze (MWM) test. The protein expression of the p75 neurotrophin receptor (p75NTR), phospho-c-Jun N-terminal kinase (p-JNK), the pro-apoptotic protein p53 and Bax were detected by Western blotting. RESULTS The Pups in the SCH and OH groups showed longer escape latencies in the MWM and decreased field-excitatory post synaptic potentials in LTP tests compared with those in the CON group. p75NTR, p-JNK, p53 and Bax expression levels in the cerebral cortex increased in pups in the SCH and OH groups compared with those in the CON group. CONCLUSIONS Maternal SCH during pregnancy may impair spatial learning and memory in the offspring and may be associated with the increased apoptosis in the cerebral cortex.
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Affiliation(s)
- Fan Zhang
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Jian Chen
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Xinyue Lin
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Shiqiao Peng
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Xiaohui Yu
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Zhongyan Shan
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Weiping Teng
- Department of Endocrinology and MetabolismInstitute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
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Song H, Zheng Y, Cai F, Ma Y, Yang J, Wu Y. c-Fos downregulation positively regulates EphA5 expression in a congenital hypothyroidism rat model. J Mol Histol 2018; 49:147-155. [PMID: 29330744 DOI: 10.1007/s10735-018-9754-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 01/05/2018] [Indexed: 12/16/2022]
Abstract
The EphA5 receptor is well established as an axon guidance molecule during neural system development and plays an important role in dendritic spine formation and synaptogenesis. Our previous study has showed that EphA5 is decreased in the developing brain of congenital hypothyroidism (CH) and the EphA5 promoter methylation modification participates in its decrease. c-Fos, a well-kown transcription factor, has been considered in association with brain development. Bioinformatics analysis showed that the EphA5 promoter region contained five putative c-fos binding sites. The chromatin immunoprecipitation (ChIP) assays were used to assess the direct binding of c-fos to the EphA5 promoter. Furthermore, dual-luciferase assays showed that these three c-fos protein binding sites were positive regulatory elements for EphA5 expression in PC12 cells. Moreover, We verified c-fos positively regulation for EphA5 expression in CH model. Q-PCR and Western blot showed that c-fos overexpression could upregulate EphA5 expression in hippocampal neurons of rats with CH. Our results suggest that c-fos positively regulates EphA5 expression in CH rat model.
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Affiliation(s)
- Honghua Song
- Department of Pediatrics, Affiliated Hospital of Nantong University, 20 Xi Si Road, Nantong, 226001, Jiangsu Province, China
| | - Yuqin Zheng
- Department of Pediatrics, Affiliated Hospital of Nantong University, 20 Xi Si Road, Nantong, 226001, Jiangsu Province, China
| | - Fuying Cai
- Department of Pediatrics, Yin Shan Lake Hospital of Wuzhong District, Suzhou, 215100, Jiangsu Province, China
| | - Yanyan Ma
- Department of Pediatrics, Affiliated Hospital of Nantong University, 20 Xi Si Road, Nantong, 226001, Jiangsu Province, China
| | - Jingyue Yang
- Department of Pediatrics, Affiliated Hospital of Nantong University, 20 Xi Si Road, Nantong, 226001, Jiangsu Province, China
| | - Youjia Wu
- Department of Pediatrics, Affiliated Hospital of Nantong University, 20 Xi Si Road, Nantong, 226001, Jiangsu Province, China.
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Calzà L, Baldassarro VA, Fernandez M, Giuliani A, Lorenzini L, Giardino L. Thyroid Hormone and the White Matter of the Central Nervous System: From Development to Repair. VITAMINS AND HORMONES 2018; 106:253-281. [DOI: 10.1016/bs.vh.2017.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Päkkilä F, Männistö T, Hartikainen AL, Suvanto E. Maternal Thyroid Function During Pregnancy and the Child's Linguistic and Sensory Development in the Northern Finland Birth Cohort 1986. Front Endocrinol (Lausanne) 2018; 9:127. [PMID: 29632517 PMCID: PMC5879546 DOI: 10.3389/fendo.2018.00127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 03/13/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Maternal hypothyroidism and hypothyroxinemia are associated with poor neuropsychological development in children. Previous research is lacking on whether maternal thyroid dysfunction affects sensory and linguistic development in childhood. METHODS The Northern Finland Birth Cohort 1986 included all births within a year (9,362 women, 9,479 children) from the two northernmost Finnish provinces. Maternal serum samples (n = 5,791) were obtained in early pregnancy and analyzed for TSH, free T4, and thyroid peroxidase antibodies (TPO-Abs). Five thousand three hundred and ninety-one parents evaluated their child's sensory and linguistic development at 7 years old via a questionnaire (excluding children with an intelligence quotient ≤85). The prevalence of sensory and linguistic impairments was compared between mothers with and without thyroid dysfunction. RESULTS There were no statistically significant differences in the prevalence of sensory or linguistic impairment between children of mothers with and without thyroid dysfunction. Children of hypothyroid and hypothyroxinemic mothers had an increased prevalence of vision impairment compared with those of euthyroid mothers (10.8 and 11.7%, respectively, versus 6.5%), but the difference was not significant. All results remained similar after excluding TPO-Ab-positive mothers and premature children. CONCLUSION We did not find an association between maternal thyroid dysfunction during pregnancy and sensory and linguistic development impairment in childhood. A somewhat higher prevalence of vision impairment was seen in children of hypothyroid and hypothyroxinemic mothers, which merits further research.
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Affiliation(s)
- Fanni Päkkilä
- Department of Obstetrics and Gynecology, University of Oulu, Oulu, Finland
- Clinic of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland
- Institute of Health Sciences, University of Oulu, Oulu, Finland
- Department of Children, Young People, and Families, National Institute for Health and Welfare, Oulu, Finland
- Medical Research Center Oulu, Oulu University Hospital, University of Oulu, Oulu, Finland
- *Correspondence: Fanni Päkkilä,
| | - Tuija Männistö
- Medical Research Center Oulu, Oulu University Hospital, University of Oulu, Oulu, Finland
- Department of Chronic Disease Prevention, National Institute for Health and Welfare, Oulu, Finland
- Northern Finland Laboratory Center Nordlab, Oulu University Hospital, University of Oulu, Oulu, Finland
- Department of Clinical Chemistry, University of Oulu, Oulu, Finland
| | - Anna-Liisa Hartikainen
- Department of Obstetrics and Gynecology, University of Oulu, Oulu, Finland
- Clinic of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland
- Medical Research Center Oulu, Oulu University Hospital, University of Oulu, Oulu, Finland
| | - Eila Suvanto
- Department of Obstetrics and Gynecology, University of Oulu, Oulu, Finland
- Clinic of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland
- Medical Research Center Oulu, Oulu University Hospital, University of Oulu, Oulu, Finland
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Singh S, Yazdani U, Gadad B, Zaman S, Hynan LS, Roatch N, Schutte C, Marti CN, Hewitson L, German DC. Serum thyroid-stimulating hormone and interleukin-8 levels in boys with autism spectrum disorder. J Neuroinflammation 2017; 14:113. [PMID: 28577577 PMCID: PMC5457729 DOI: 10.1186/s12974-017-0888-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/24/2017] [Indexed: 12/14/2022] Open
Abstract
Background Autism spectrum disorder (ASD) affects approximately 1 in 68 children in the USA. An ASD blood biomarker may enable early diagnosis and/or identification of new therapeutic targets. Serum samples from ASD and typically developing (TD) boys (n = 30/group) were screened for differences in 110 proteins using a multiplex immunoassay. Results Eleven proteins were found that together could confirm ASD with modest accuracy using multiple training and test sets. Two of the 11 proteins identified here were further tested using a different detection platform and with a larger sample of ASD and TD boys. The two proteins, thyroid-stimulating hormone (TSH) and interleukin-8 (IL-8), have been previously identified as putative biomarkers for ASD. TSH levels were significantly lower in ASD boys, whereas IL-8 levels were significantly elevated. The diagnostic accuracy for ASD based upon TSH or IL-8 levels alone varied from 74 to 76%, but using both proteins together, the diagnostic accuracy increased to 82%. In addition, TSH levels were negatively correlated with the Autism Diagnostic Observation Schedule subdomain scores. Conclusions These data suggest that a panel of proteins may be useful as a putative blood biomarker for ASD.
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Affiliation(s)
- Sarika Singh
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA.,Present Address: Toxicology Division, CSIR-CDRI, Lucknow, 226021, Uttar Pradesh, India
| | - Umar Yazdani
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA
| | - Bharathi Gadad
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA
| | - Sayed Zaman
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA
| | - Linda S Hynan
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA.,Department of Clinical Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390, USA
| | - Nichole Roatch
- The Johnson Center for Child Health and Development, 1700 Rio Grande St., Austin, TX, 78701, USA
| | - Claire Schutte
- The Johnson Center for Child Health and Development, 1700 Rio Grande St., Austin, TX, 78701, USA
| | | | - Laura Hewitson
- The Johnson Center for Child Health and Development, 1700 Rio Grande St., Austin, TX, 78701, USA
| | - Dwight C German
- Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-9070, USA.
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Implications of the thyroid hormone on neuronal development with special emphasis on the calmodulin-kinase IV pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:877-882. [PMID: 27939430 DOI: 10.1016/j.bbamcr.2016.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 11/29/2016] [Accepted: 12/02/2016] [Indexed: 12/16/2022]
Abstract
Thyroid hormones influence brain development through regulation of gene expression. This is especially true for Ca2+-dependent regulation since a major pathway is controlled by the Ca2+/calmodulin-dependent protein kinase IV (CaMKIV) which in turn is induced by the thyroid hormone T3. In addition, CaMKIV is involved in regulation of alternative splicing of a number of protein isoforms, among them PMCA1a, the neuronal specific isoform of the plasma membrane calcium pump. On the other hand, hypothyroidism or CaMKIV deficiency can have a severe influence on brain development. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Kyono Y, Sachs LM, Bilesimo P, Wen L, Denver RJ. Developmental and Thyroid Hormone Regulation of the DNA Methyltransferase 3a Gene in Xenopus Tadpoles. Endocrinology 2016; 157:4961-4972. [PMID: 27779916 PMCID: PMC5133355 DOI: 10.1210/en.2016-1465] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 10/21/2016] [Indexed: 11/19/2022]
Abstract
Thyroid hormone is essential for normal development in vertebrates. In amphibians, T3 controls metamorphosis by inducing tissue-specific gene regulation programs. A hallmark of T3 action is the modification of chromatin structure, which underlies changes in gene transcription. We found that mRNA for the de novo DNA methyltransferase (DNMT) dnmt3a, but not dnmt1, increased in the brain of Xenopus tadpoles during metamorphosis in parallel with plasma [T3]. Addition of T3 to the rearing water caused a time-dependent increase in dnmt3a mRNA in tadpole brain, tail, and hind limb. By analyzing data from a genome-wide analysis of T3 receptor (TR) binding in tadpole tail, we identified several putative T3 response elements (TREs) within the dnmt3a locus. Using in vitro DNA binding, transient transfection-reporter, and chromatin immunoprecipitation assays for TRs, we identified two functional TREs at -7.1 kb and +5.1 kb relative to the dnmt3a transcription start site. Sequence alignment showed that these TREs are conserved between two related frog species, X. laevis and X. tropicalis, but not with amniotes. Our previous findings showed that this gene is directly regulated by liganded TRs in mouse brain, and whereas the two mouse TREs are conserved among Eutherian mammals, they are not conserved in Xenopus species. Thus, although T3 regulation of dnmt3a may be an ancient pathway in vertebrates, the genomic sites responsible for hormone regulation may have diverged or arisen by convergent evolution. We hypothesize that direct T3 regulation of dnmt3a may be an important mechanism for modulating global changes in DNA methylation.
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Affiliation(s)
- Yasuhiro Kyono
- Neuroscience Graduate Program (Y.K.), The University of Michigan, Ann Arbor, Michigan 48109-1048; UMR-7221, Centre National de la Recherche Scientifique (L.M.S., P.B.), Muséum National d'Histoire Naturelle, 75005 Paris, France; and Department of Molecular, Cellular, and Developmental Biology (L.W., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109-1048
| | - Laurent M Sachs
- Neuroscience Graduate Program (Y.K.), The University of Michigan, Ann Arbor, Michigan 48109-1048; UMR-7221, Centre National de la Recherche Scientifique (L.M.S., P.B.), Muséum National d'Histoire Naturelle, 75005 Paris, France; and Department of Molecular, Cellular, and Developmental Biology (L.W., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109-1048
| | - Patrice Bilesimo
- Neuroscience Graduate Program (Y.K.), The University of Michigan, Ann Arbor, Michigan 48109-1048; UMR-7221, Centre National de la Recherche Scientifique (L.M.S., P.B.), Muséum National d'Histoire Naturelle, 75005 Paris, France; and Department of Molecular, Cellular, and Developmental Biology (L.W., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109-1048
| | - Luan Wen
- Neuroscience Graduate Program (Y.K.), The University of Michigan, Ann Arbor, Michigan 48109-1048; UMR-7221, Centre National de la Recherche Scientifique (L.M.S., P.B.), Muséum National d'Histoire Naturelle, 75005 Paris, France; and Department of Molecular, Cellular, and Developmental Biology (L.W., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109-1048
| | - Robert J Denver
- Neuroscience Graduate Program (Y.K.), The University of Michigan, Ann Arbor, Michigan 48109-1048; UMR-7221, Centre National de la Recherche Scientifique (L.M.S., P.B.), Muséum National d'Histoire Naturelle, 75005 Paris, France; and Department of Molecular, Cellular, and Developmental Biology (L.W., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109-1048
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Kyono Y, Subramani A, Ramadoss P, Hollenberg AN, Bonett RM, Denver RJ. Liganded Thyroid Hormone Receptors Transactivate the DNA Methyltransferase 3a Gene in Mouse Neuronal Cells. Endocrinology 2016; 157:3647-57. [PMID: 27387481 PMCID: PMC5007891 DOI: 10.1210/en.2015-1529] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 07/01/2016] [Indexed: 12/11/2022]
Abstract
Thyroid hormone (T3) is essential for proper neurological development. The hormone, bound to its receptors, regulates gene transcription in part by modulating posttranslational modifications of histones. Methylation of DNA, which is established by the de novo DNA methyltransferase (DNMT)3a and DNMT3b, and maintained by DNMT1 is another epigenetic modification influencing gene transcription. The expression of Dnmt3a, but not other Dnmt genes, increases in mouse brain in parallel with the postnatal rise in plasma [T3]. We found that treatment of the mouse neuroblastoma cell line Neuro2a[TRβ1] with T3 caused rapid induction of Dnmt3a mRNA, which was resistant to protein synthesis inhibition, supporting that it is a direct T3-response gene. Injection of T3 into postnatal day 6 mice increased Dnmt3a mRNA in the brain by 1 hour. Analysis of two chromatin immunoprecipitation-sequencing datasets, and targeted analyses using chromatin immunoprecipitation, transfection-reporter assays, and in vitro DNA binding identified 2 functional T3-response elements (TREs) at the mouse Dnmt3a locus located +30.3 and +49.3 kb from the transcription start site. Thyroid hormone receptors associated with both of these regions in mouse brain chromatin, but with only 1 (+30.3 kb) in Neuro2a[TRβ1] cells. Deletion of the +30.3-kb TRE using CRISPR/Cas9 genome editing eliminated or strongly reduced the Dnmt3a mRNA response to T3. Bioinformatics analysis showed that both TREs are highly conserved among eutherian mammals. Thyroid regulation of Dnmt3a may be an evolutionarily conserved mechanism for modulating global changes in DNA methylation during postnatal neurological development.
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Affiliation(s)
- Yasuhiro Kyono
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
| | - Arasakumar Subramani
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
| | - Preeti Ramadoss
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
| | - Anthony N Hollenberg
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
| | - Ronald M Bonett
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
| | - Robert J Denver
- Neuroscience Graduate Program (Y.K., R.J.D.) and Department of Molecular, Cellular and Developmental Biology (A.S., R.J.D.), The University of Michigan, Ann Arbor, Michigan 48109; Division of Endocrinology, Diabetes and Metabolism (P.R., A.N.H.), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115; and Department of Biological Science (R.M.B.), The University of Tulsa, Tulsa, Oklahoma 74104
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25
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Simic N, Rovet J. Dorsal and ventral visual streams: Typical and atypical development. Child Neuropsychol 2016; 23:678-691. [DOI: 10.1080/09297049.2016.1186616] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Nevena Simic
- Neurosciences & Mental Health Program, The Hospital for Sick Children, Toronto, Canada
- Department of Psychology, University of Toronto, Canada
| | - Joanne Rovet
- Neurosciences & Mental Health Program, The Hospital for Sick Children, Toronto, Canada
- Department of Psychology, University of Toronto, Canada
- Department of Paediatrics, University of Toronto, Canada
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26
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Olivares AM, Moreno-Ramos OA, Haider NB. Role of Nuclear Receptors in Central Nervous System Development and Associated Diseases. J Exp Neurosci 2016; 9:93-121. [PMID: 27168725 PMCID: PMC4859451 DOI: 10.4137/jen.s25480] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 01/06/2016] [Accepted: 01/07/2016] [Indexed: 11/13/2022] Open
Abstract
The nuclear hormone receptor (NHR) superfamily is composed of a wide range of receptors involved in a myriad of important biological processes, including development, growth, metabolism, and maintenance. Regulation of such wide variety of functions requires a complex system of gene regulation that includes interaction with transcription factors, chromatin-modifying complex, and the proper recognition of ligands. NHRs are able to coordinate the expression of genes in numerous pathways simultaneously. This review focuses on the role of nuclear receptors in the central nervous system and, in particular, their role in regulating the proper development and function of the brain and the eye. In addition, the review highlights the impact of mutations in NHRs on a spectrum of human diseases from autism to retinal degeneration.
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Affiliation(s)
- Ana Maria Olivares
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Oscar Andrés Moreno-Ramos
- Departamento de Ciencias Biológicas, Facultad de Ciencias, Universidad de los Andes, Bogotá, Colombia
| | - Neena B Haider
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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Darnall RA, Schneider RW, Tobia CM, Commons KG. Eliminating medullary 5-HT neurons delays arousal and decreases the respiratory response to repeated episodes of hypoxia in neonatal rat pups. J Appl Physiol (1985) 2015; 120:514-25. [PMID: 26702023 DOI: 10.1152/japplphysiol.00560.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 12/21/2015] [Indexed: 11/22/2022] Open
Abstract
Arousal from sleep is a critical defense mechanism when infants are exposed to hypoxia, and an arousal deficit has been postulated as contributing to the etiology of the sudden infant death syndrome (SIDS). The brainstems of SIDS infants are deficient in serotonin (5-HT) and tryptophan hydroxylase (TPH) and have decreased binding to 5-HT receptors. This study explores a possible connection between medullary 5-HT neuronal activity and arousal from sleep in response to hypoxia. Medullary raphe 5-HT neurons were eliminated from neonatal rat pups with intracisterna magna (CM) injections of 5,7-dihydroxytryptamine (DHT) at P2-P3. Each pup was then exposed to four episodes of hypoxia during sleep at three developmental ages (P5, P15, and P25) to produce an arousal response. Arousal, heart rate, and respiratory rate responses of DHT-injected pups were compared with pups that received CM artificial cerebrospinal fluid (aCSF) and those that received DHT but did not have a significant reduction in medullary 5-HT neurons. During each hypoxia exposure, the time to arousal from the onset of hypoxia (latency) was measured together with continuous measurements of heart and respiratory rates, oxyhemoglobin saturation, and chamber oxygen concentration. DHT-injected pups with significant losses of medullary 5-HT neurons exhibited significantly longer arousal latencies and decreased respiratory rate responses to hypoxia compared with controls. These results support the hypothesis that in newborn and young rat pups, 5-HT neurons located in the medullary raphe contribute to the arousal response to hypoxia. Thus alterations medullary 5-HT mechanisms might contribute to an arousal deficit and contribute to death in SIDS infants.
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Affiliation(s)
- Robert A Darnall
- Department of Physiology and Neurobiology and Department of Pediatrics, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire;
| | | | | | - Kathryn G Commons
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, and Department of Anesthesia, Harvard Medical School, Boston, Massachusetts
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28
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Shakya PR, Gelal B, Lal Das BK, Lamsal M, Pokharel PK, Nepal AK, Brodie DA, Sah GS, Baral N. Urinary iodine excretion and thyroid function status in school age children of hilly and plain regions of Eastern Nepal. BMC Res Notes 2015; 8:374. [PMID: 26306673 PMCID: PMC4548539 DOI: 10.1186/s13104-015-1359-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 08/17/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Iodine deficiency is a major public health problem in many developing countries including Nepal. The present study was designed to investigate the urinary iodine excretion (UIE), thyroid function status and household salt iodine content (SIC) in school-aged children (SAC) and to establish the relationships between these factors. METHODS A community-based cross sectional study was conducted in selected schools of two districts, Tehrathum and Morang, lying in the hill and plain region of eastern Nepal respectively. A total of 640 SAC, (Tehrathum n = 274 and Morang n = 366) aged 6-11 years, were assessed for UIE and household SIC. Among the 640 children, 155 consented to blood samples (Tehrathum n = 78 and Morang n = 77) to test for serum thyroglobulin (Tg), thyroid stimulating hormone (TSH), free triiodothyronine (fT3) and free thyroxine (fT4). UIE was measured by ammonium persulfate digestion method. SIC was measured by iodometric titration method and Tg, TSH, fT4 and fT3 were measured by immunoassay based kit method. RESULTS In Tehrathum and Morang, 9.5 and 7.7% of SAC had UIE values of UIE <100 µg/L while 59.5 and 41% had iodine nutrition values of >299 µg/L, with median UIE of 345.65 and 270.36 µg/L respectively. The overall medians were as follows, Tg 14.29 µg/L, fT3 3.94 pmol/L, fT4 16.25 pmol/L and TSH 3.61 mIU/L. There was a negative correlation between UIE and Tg (r = -0.236, p = 0.003) and a positive correlation between UIE and SIC (r = 0.349, p < 0.0001). We found 19.5%, n = 15 and 16.7%, n = 13 subclinical hypothyroid cases in Morang and Tehrathum respectively. Iodometric titration showed only 6.4% (n = 41) of the samples had household SIC <15 ppm. Multivariate analysis revealed that use of packaged salt by SAC of Tehrathum district correlated with higher UIE values. CONCLUSIONS Our focused data suggests that collaborative universal salt iodization (USI) programs are improving the health of children in the Tehrathum and Morang districts of Nepal. We also found that excessive iodine in a large portion of the study groups is a substantial concern and iodine intervention programs need to deal with both deficient and excessive iodine scenarios that can both be present simultaneously in study populations.
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Affiliation(s)
- Prem Raj Shakya
- Department of Biochemistry, School of Medicine, Patan Academy of Health Sciences, Lagankhel-5, PO Box: 26500, Lalitpur, Nepal.
| | - Basanta Gelal
- Department of Biochemistry, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - Binod Kumar Lal Das
- Department of Biochemistry, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - Madhab Lamsal
- Department of Biochemistry, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - Paras Kumar Pokharel
- Department of Community Medicine, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - Ashwini Kumar Nepal
- Department of Biochemistry, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - David A Brodie
- Department of Biochemistry, Faculty of Society and Health, Bucks New University, High Wycombe, Buckinghamshire, UK.
| | - Gauri Shankar Sah
- Department of Paediatrics and Adolescent Medicine, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
| | - Nirmal Baral
- Department of Biochemistry, B.P. Koirala Institute of Health Sciences, Dharan, Nepal.
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Bordbar A, Farjadnia M. Maternal Morbidities and Occurrence of Intraventricular Hemorrhage in Preterm Infants. J Pediatr Intensive Care 2015; 4:156-161. [PMID: 31110865 DOI: 10.1055/s-0035-1559825] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/24/2015] [Indexed: 01/18/2023] Open
Abstract
Intraventricular hemorrhage (IVH) is one of the most serious neurological morbidities in preterm infants. Several prenatal, intrapartum, and neonatal risk factors have been detected in different studies. However, maternal conditions that may render the neonates to IVH have been the subject of very few studies. Preterm infants with and without IVH were included in the study, and maternal obstetrics and general health clinical files were reviewed for any kind of morbidity. Data were then analyzed with statistical software to assess the association between maternal conditions and IVH. A total of 115 neonates with IVH and 120 infants without IVH were recruited. Among all maternal conditions, prolonged rupture of membrane (p = 0.00), laparoscopic surgery for infertility (p = 0.001), and in vitro fertilization (IVF) (p = 0.00) increased the risk of IVH in neonates significantly. IVF remained strongly associated with IVH even after controlling for confounding variables (odds ratio: 9.75; confidence interval: 2.66-35.75; p = 0.001). Based on our findings, prolonged rupture of membrane and IVF were maternal conditions that increased the risk of IVH. Laparoscopic surgery for infertility was also associated with an increased risk of IVH.
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Affiliation(s)
- Arash Bordbar
- Department of Neonatology, Akbarabadi Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Mahgol Farjadnia
- Department of Neonatology, Akbarabadi Hospital, Iran University of Medical Sciences, Tehran, Iran
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30
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Sirieix CM, Tobia CM, Schneider RW, Darnall RA. Impaired arousal in rat pups with prenatal alcohol exposure is modulated by GABAergic mechanisms. Physiol Rep 2015; 3:3/6/e12424. [PMID: 26059034 PMCID: PMC4510626 DOI: 10.14814/phy2.12424] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Prenatal alcohol exposure (PAE) increases the risk for The Sudden Infant Death Syndrome (SIDS) in human infants. In rat pups, the arousal response to hypoxia is modulated by medullary raphe GABAergic mechanisms. We hypothesized that arousal to hypoxia is impaired by PAE, and is associated with an increase in medullary GABA and enhanced GABAergic activity. Pregnant dams received an ethanol liquid diet (ETOH), an iso-caloric pair fed diet (PF) or a standard chow diet (CHOW). We first measured the time to arousal (latency), during four episodes of hypoxia in P5, P15, and P21 CHOW, PF, and ETOH pups. We also measured brainstem GABA concentration in the same groups of pups. Finally, we injected artificial cerebrospinal fluid (aCSF), nipecotic acid (NIP) or gabazine into the medullary raphe of P15 and P21 pups receiving the three diets. For statistical analysis, the PF and CHOW groups were combined into a single CONTROL group. Our main finding was that compared to CONTROL, arousal latency to hypoxia is increased in ETOH pups at P15 and P21, and the concentration of brainstem GABA is elevated at P21. NIP administration in CONTROL pups led to arousal latencies similar in magnitude to those in ETOH pups after aCSF injection. NIP injected ETOH pups had no further increases in arousal latency. We conclude that PAE impairs arousal latency and this is mediated or modulated by medullary GABAergic mechanisms.
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Affiliation(s)
- Chrystelle M Sirieix
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Christine M Tobia
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Robert W Schneider
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Robert A Darnall
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire Department of Pediatrics, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
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31
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Treatment with Iodine in Pregnant Rats with Marginal Iodine Deficiency Improves Cell Migration in the Developing Brain of the Progeny. Mol Neurobiol 2015; 53:2212-21. [PMID: 25963726 DOI: 10.1007/s12035-015-9155-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 03/19/2015] [Indexed: 02/01/2023]
Abstract
Marginal iodine deficiency is a common health problem in pregnant women. Epidemiological and animal studies had shown that marginally maternal iodine deficiency could cause the mild changes of maternal thyroid function, eventually lead to a negative effect on neurodevelopment. But the underlying mechanisms responsible for the neurological impairment remain unclear. The aim of this study is to explore whether marginally maternal iodine deficiency could produce subtle changes in cell migration and cognitive function of offspring, and the optimal time of giving intervention to minimize the adverse effects. In the present study, we established a marginal iodine deficiency model, and iodine supplement was performed on pre-pregnancy (PP), G13 (gestation day 13), and postnatal day 0 (P0). Our data showed that there were changes in the cytoarchitecture and the percentage of bromodeoxyuridine (BrdU)-labeled cells in the cerebral cortex in marginal iodine deficiency rats. The Reelin expression was significantly lower, but Tenascin-C was higher in the cerebral cortex of marginal iodine deficiency group on P7 than the normal group, respectively. When iodine supplement, especially before G13 could reverse the abnormal expression of the two proteins involved in cell migration, which was consistent with the results of Morris Water Maze test. The three intervention groups had shorter escape latencies than the marginal iodine deficiency rats. The earlier that iodine is supplied, the better behavior performance would reach. Our findings suggested that iodine supplement in early stage of pregnancy could improve the cell migration of cerebral cortex and neurodevelopment of offspring.
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Abstract
Most of our knowledge on the mechanisms of thyroid hormone (TH) dependent brain development is based on clinical observations and animal studies of maternal/fetal hypothyroidism. THs play an essential role in brain development and hormone deficiency during critical phases in fetal life may lead to severe and permanent brain damage. Maternal hypothyroidism is considered the most common cause of fetal TH deficiency, but the problem may also arise in the fetus. In the case of congenital hypothyroidism due to defects in fetal thyroid gland development or hormone synthesis, clinical symptoms at birth are often mild as a result of compensatory maternal TH supply. TH transporters (THTs) and deiodinases (Ds) are important regulators of intracellular triiodothyronine (T3) availability and therefore contribute to the control of thyroid receptors (TRs)-dependent CNS development and early embryonic life. Defects in fetal THTs or Ds may have more impact on fetal brain since they can result in intracellular T3 deficiency despite sufficient maternal TH supply. One clear example is the recent discovery of mutations in the TH transporter (monocarboxylate transporter 8; MCT8) that could be linked to a syndrome of severe and non reversible psychomotor retardation. Even mild and transient changes in maternal TH levels can directly affect and alter the gene expression profile, and thus disturb fetal brain development. Animal studies are needed to increase our understanding of the exact role of THTs and Ds in prenatal brain development.
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Affiliation(s)
- R G Ahmed
- Division of Anatomy and Embryology, Zoology Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt
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33
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Developmental neurotoxicity of 3,3',4,4'-tetrachloroazobenzene with thyroxine deficit: Sensitivity of glia and dentate granule neurons in the absence of behavioral changes. TOXICS 2014; 2:496-532. [PMID: 26029700 PMCID: PMC4445902 DOI: 10.3390/toxics2030496] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Thyroid hormones (TH) regulate biological processes implicated in neurodevelopmental disorders and can be altered with environmental exposures. Developmental exposure to the dioxin-like compound, 3,3',4,4'-tetrachloroazobenzene (TCAB), induced a dose response deficit in serum T4 levels with no change in 3,5,3'- triiodothyronine or thyroid stimulating hormone. Female Sprague-Dawley rats were orally gavaged (corn oil, 0.1, 1.0, or 10 mg TCAB/kg/day) two weeks prior to cohabitation until post-partum day 3 and male offspring from post-natal day (PND)4-21. At PND21, the high dose showed a deficit in body weight gain. Conventional neuropathology detected no neuronal death, myelin disruption, or gliosis. Astrocytes displayed thinner and less complex processes at 1.0 and 10 mg/kg/day. At 10 mg/kg/day, microglia showed less complex processes, unbiased stereology detected fewer hippocampal CA1 pyramidal neurons and dentate granule neurons (GC) and Golgi staining of the cerebellum showed diminished Purkinje cell dendritic arbor. At PND150, normal maturation of GC number and Purkinje cell branching area was not observed in the 1.0 mg/kg/day dose group with a diminished number and branching suggestive of effects initiated during developmental exposure. No effects were observed on post-weaning behavioral assessments in control, 0.1 and 1.0mg/kg/day dose groups. The demonstrated sensitivity of hippocampal neurons and glial cells to TCAB and T4 deficit raises support for considering additional anatomical features of brain development in future DNT evaluations.
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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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35
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Berbel P, Navarro D, Román GC. An evo-devo approach to thyroid hormones in cerebral and cerebellar cortical development: etiological implications for autism. Front Endocrinol (Lausanne) 2014; 5:146. [PMID: 25250016 PMCID: PMC4158880 DOI: 10.3389/fendo.2014.00146] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 08/25/2014] [Indexed: 12/11/2022] Open
Abstract
The morphological alterations of cortical lamination observed in mouse models of developmental hypothyroidism prompted the recognition that these experimental changes resembled the brain lesions of children with autism; this led to recent studies showing that maternal thyroid hormone deficiency increases fourfold the risk of autism spectrum disorders (ASD), offering for the first time the possibility of prevention of some forms of ASD. For ethical reasons, the role of thyroid hormones on brain development is currently studied using animal models, usually mice and rats. Although mammals have in common many basic developmental principles regulating brain development, as well as fundamental basic mechanisms that are controlled by similar metabolic pathway activated genes, there are also important differences. For instance, the rodent cerebral cortex is basically a primary cortex, whereas the primary sensory areas in humans account for a very small surface in the cerebral cortex when compared to the associative and frontal areas that are more extensive. Associative and frontal areas in humans are involved in many neurological disorders, including ASD, attention deficit-hyperactive disorder, and dyslexia, among others. Therefore, an evo-devo approach to neocortical evolution among species is fundamental to understand not only the role of thyroid hormones and environmental thyroid disruptors on evolution, development, and organization of the cerebral cortex in mammals but also their role in neurological diseases associated to thyroid dysfunction.
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Affiliation(s)
- Pere Berbel
- Departamento de Histología y Anatomía, Facultad de Medicina, Universidad Miguel Hernández, Alicante, Spain
| | - Daniela Navarro
- Departamento de Histología y Anatomía, Facultad de Medicina, Universidad Miguel Hernández, Alicante, Spain
| | - Gustavo C. Román
- Department of Neurology, Weill Cornell Medical College, Cornell University, New York, NY, USA
- Methodist Neurological Institute, Houston, TX, USA
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Maternal Subclinical Hypothyroidism Impairs Neurodevelopment in Rat Offspring by Inhibiting the CREB Signaling Pathway. Mol Neurobiol 2014; 52:432-41. [PMID: 25193019 DOI: 10.1007/s12035-014-8855-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 08/06/2014] [Indexed: 12/29/2022]
Abstract
Thyroid hormone is indispensable for fetal brain development, and maternal thyroid hormone deficiency is thought to result in severe and irreversible brain impairments in learning and memory. Epidemiological and animal studies by our group had shown that maternal subclinical hypothyroidism had significant negative impact on neurodevelopment. But, the underlying mechanisms responsible for these neurological alterations remain unclear. In the present study, we performed thyroidectomy and injected L-T4 daily in Wistar rats to induce maternal subclinical hypothyroidism. Our data indicated that the pups from subclinical group showed prolonged latencies during the learning process in the Morris water maze as compared to the control group. Transcription factor cAMP response element-binding protein (CREB) signaling pathway is closely associated with synaptic plasticity, learning, and memory. Consistent with behavioral results, Western blotting also showed decreased activation of three important upstream modulators of CREB signaling pathway: phospho-mitogen-activated protein kinases (P-ERK1/2), phospho-calcium-dependent-calmodulin kinase IV (P-CaMKIV), phospho-serine/threonine protein kinase AKT(P-AKT), as well as total CREB and phospho-CREB as compared to the control at postnatal day 7 (PND 7) in hippocampus. Our findings suggested that decreased activation of the CREB signaling pathway in pups was related to impairments of cognitive function caused by maternal subclinical hypothyroidism.
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Gilbert ME, Ramos RL, McCloskey DP, Goodman JH. Subcortical band heterotopia in rat offspring following maternal hypothyroxinaemia: structural and functional characteristics. J Neuroendocrinol 2014; 26:528-41. [PMID: 24889016 DOI: 10.1111/jne.12169] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/19/2014] [Accepted: 05/28/2014] [Indexed: 01/22/2023]
Abstract
Thyroid hormones (TH) play crucial roles in brain maturation and are important for neuronal migration and neocortical lamination. Subcortical band heterotopia (SBH) represent a class of neuronal migration errors in humans that are often associated with childhood epilepsy. We have previously reported the presence of SBH in a rodent model of low level hypothyroidism induced by maternal exposure to the goitrogen, propylthiouracil (PTU). In the present study, we report the dose-response characteristics of this developmental malformation and the connectivity of heterotopic neurones with other brain regions, as well as their functionality. Pregnant rats were exposed to varying concentrations of PTU through the drinking water (0-10 p.p.m.) beginning on gestational day 6 to produce graded levels of TH insufficiency. Dose-dependent increases in the volume of the SBH present in the corpus callosum were documented in the adult offspring, with a clear presence at concentrations of PTU that resulted in minor (< 15%) reductions in maternal serum thyroxine as measured when pups were weaned. SBH contain neurones, oligodendrocytes, astrocytes and microglia. Monoaminergic and cholinergic processes were prevalent and many of the axons were myelinated. Anatomical connectivity of SBH neurones to cortical neurones and the synaptic functionality of these anatomical connections was verified by ex vivo field potential recordings. SBH persisted in adult offspring despite a return to euthyroid status on termination of exposure and these offspring displayed an increased sensitivity to seizures. Features of this model are attractive with respect to the investigation of the molecular mechanisms of cortical development, the effectiveness of therapeutic intervention in hypothyroxinaemia during pregnancy and the impact of the very modest TH imbalance that accompanies exposure to environmental contaminants.
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Affiliation(s)
- M E Gilbert
- Toxicity Assessment Division, Neurotoxicology Branch, US Environmental Protection Agency, Research Triangle Park, NC, USA
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Kurian MA, Jungbluth H. Genetic disorders of thyroid metabolism and brain development. Dev Med Child Neurol 2014; 56:627-34. [PMID: 24665922 PMCID: PMC4231219 DOI: 10.1111/dmcn.12445] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/13/2014] [Indexed: 01/28/2023]
Abstract
Normal thyroid metabolism is essential for human development, including the formation and functioning of the central and peripheral nervous system. Disorders of thyroid metabolism are increasingly recognized within the spectrum of paediatric neurological disorders. Both hypothyroid and hyperthyroid disease states (resulting from genetic and acquired aetiologies) can lead to characteristic neurological syndromes, with cognitive delay, extrapyramidal movement disorders, neuropsychiatric symptoms, and neuromuscular manifestations. In this review, the neurological manifestations of genetic disorders of thyroid metabolism are outlined, with particular focus on Allan-Herndon-Dudley syndrome and benign hereditary chorea. We report in detail the clinical features, major neurological and neuropsychiatric manifestations, molecular genetic findings, disease mechanisms, and therapeutic strategies for these emerging genetic 'brain-thyroid' disorders.
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Affiliation(s)
- Manju A Kurian
- Developmental Neurosciences, UCL-Institute of Child HealthLondon, UK,Department of Neurology, Great Ormond Street Hospital for ChildrenLondon, UK,Correspondence to Manju Kurian, Institute of Child Health, Level 1 CMGU Room 111, 30 Guilford Street, London WC1N 1EH, UK. E-mail:
| | - Heinz Jungbluth
- Department of Paediatric Neurology, Evelina Children's Hospital, Guy's & St Thomas' NHS Foundation TrustLondon, UK,Randall Division for Cell and Molecular Biophysics, Muscle Signalling Section, King's College LondonLondon, UK,Clinical Neuroscience Division, Institute of Psychiatry, King's College LondonLondon, UK
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Faustino LC, Ortiga-Carvalho TM. Thyroid hormone role on cerebellar development and maintenance: a perspective based on transgenic mouse models. Front Endocrinol (Lausanne) 2014; 5:75. [PMID: 24904526 PMCID: PMC4033007 DOI: 10.3389/fendo.2014.00075] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/02/2014] [Indexed: 01/15/2023] Open
Abstract
Cerebellum development is sensitive to thyroid hormone (TH) levels, as THs regulate neuronal migration, differentiation, and myelination. Most effects of THs are mediated by the thyroid hormone receptor (TR) isoforms TRβ1, TRβ2, and TRα1. Studies aimed at identifying TH target genes during cerebellum development have only achieved partial success, as some of these genes do not possess classical TH-responsive elements, and those that do are likely to be temporally and spatially regulated by THs. THs may also affect neurodevelopment by regulating transcription factors that control particular groups of genes. Furthermore, TH action can also be affected by TH transport, which is mediated mainly by monocarboxylate transporter family members. Studies involving transgenic animal models and genome-wide expression analyses have helped to address the unanswered questions regarding the role of TH in cerebellar development. Recently, a growing body of evidence has begun to clarify the molecular, cellular, and functional aspects of THs in the developing cerebellum. This review describes the current findings concerning the effects of THs on cerebellar development and maintenance as well as advances in the genetic animal models used in this field.
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Affiliation(s)
- Larissa C. Faustino
- Laboratorio de Endocrinologia Molecular, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tania M. Ortiga-Carvalho
- Laboratorio de Endocrinologia Molecular, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Tania M. Ortiga-Carvalho, Laboratorio de Endocrinologia Molecular, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, s/n Cidade Universitária, Rio de Janeiro 21941-902, Brazil e-mail:
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Vázquez-Salas RA, López-Carrillo L, Menezes-Filho JA, Rothenberg SJ, Cebrián ME, Schnaas L, Viana GFDS, Torres-Sánchez L. Prenatal molybdenum exposure and infant neurodevelopment in Mexican children. Nutr Neurosci 2013; 17:72-80. [PMID: 24479423 DOI: 10.1179/1476830513y.0000000076] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVE To evaluate the association between prenatal exposure to molybdenum (Mo) and infant neurodevelopment during the first 30 months of life. METHODS We selected a random sample of 147 children who participated in a prospective cohort study in four municipalities in the State of Morelos, Mexico. The children were the products of uncomplicated pregnancies with no perinatal asphyxia, with a weight of ≥2 kg at birth, and whose mothers had no history of chronic illnesses. These women were monitored before, during, and after the pregnancy. For each of these children a maternal urine sample was available for at least one trimester of pregnancy, and urine Mo levels were determined by electrothermal atomic absorption spectrometry. Neurodevelopment was evaluated using the psychomotor (PDI) and mental development indices (MDI) of the Bayley scale. Association between prenatal exposure to Mo and infant neurodevelopment was estimated using generalized mixed effect models. RESULTS The average urinary concentrations of Mo adjusted for creatinine varied between 45.6 and 54.0 µg/g of creatinine at first and third trimester, respectively. For each doubling increase of Mo (μg/g creatinine) during the third trimester of pregnancy, we observed a significant reduction on PDI (β = -0.57 points; P = 0.03), and no effect on MDI (β = 0.07 points; P = 0.66). DISCUSSION As this is the first study that suggests a potential negative association between prenatal Mo exposure and infant neurodevelopment, these results require further confirmation.
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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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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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Dong J, Wang Y, Wang Y, Wei W, Min H, Song B, Xi Q, Teng W, Chen J. Iodine deficiency increases apoptosis and decreases synaptotagmin-1 and PSD-95 in rat hippocampus. Nutr Neurosci 2013; 16:135-41. [DOI: 10.1179/1476830512y.0000000040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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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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Hassan WA, Rahman TA, Aly MS, Shahat AS. Alterations in monoamines level in discrete brain regions and other peripheral tissues in young and adult male rats during experimental hyperthyroidism. Int J Dev Neurosci 2013; 31:311-8. [DOI: 10.1016/j.ijdevneu.2013.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 03/03/2013] [Accepted: 03/03/2013] [Indexed: 11/26/2022] Open
Affiliation(s)
- Wafaa A. Hassan
- National Organisation for Drug Control and ResearchHormone Evaluation Department11511CairoEgypt
| | | | - Mona S. Aly
- Cairo UniversityFaculty of Science, Zoology DepartmentCairo12613Egypt
| | - Asmaa S. Shahat
- National Organisation for Drug Control and ResearchHormone Evaluation Department11511CairoEgypt
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Torres-Sánchez L, Schnaas L, Rothenberg SJ, Cebrián ME, Osorio-Valencia E, Hernández MDC, García-Hernández RM, López-Carrillo L. Prenatal p,p´-DDE exposure and neurodevelopment among children 3.5-5 years of age. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:263-8. [PMID: 23151722 PMCID: PMC3569679 DOI: 10.1289/ehp.1205034] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 11/13/2012] [Indexed: 05/20/2023]
Abstract
BACKGROUND The results of previous studies suggest that prenatal exposure to bis[p-chlorophenyl]-1,1,1-trichloroethane (DDT) and to its main metabolite, 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), impairs psychomotor development during the first year of life. However, information about the persistence of this association at later ages is limited. OBJECTIVES We assessed the association of prenatal DDE exposure with child neurodevelopment at 42-60 months of age. METHODS Since 2001 we have been monitoring the neurodevelopment in children who were recruited at birth into a perinatal cohort exposed to DDT, in the state of Morelos, Mexico. We report McCarthy Scales of Children's Abilities for 203 children at 42, 48, 54, and 60 months of age. Maternal DDE serum levels were available for at least one trimester of pregnancy. The Home Observation for Measurement of the Environment scale and other covariables of interest were also available. RESULTS After adjustment, a doubling of DDE during the third trimester of pregnancy was associated with statistically significant reductions of -1.37, -0.88, -0.84, and -0.80 points in the general cognitive index, quantitative, verbal, and memory components respectively. The association between prenatal DDE and the quantitative component was weaker at 42 months than at older ages. No significant statistical interactions with sex or breastfeeding were observed. CONCLUSIONS These findings support the hypothesis that prenatal DDE impairs early child neurodevelopment; the potential for adverse effects on development should be considered when using DDT for malaria control.
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Gilbert ME, Lasley SM. Developmental thyroid hormone insufficiency and brain development: a role for brain-derived neurotrophic factor (BDNF)? Neuroscience 2012. [PMID: 23201250 DOI: 10.1016/j.neuroscience.2012.11.022] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Thyroid hormones (TH) are essential for normal brain development. Even modest degrees of TH disruption experienced in utero can result in neuropsychological deficits in children despite normal thyroid status at birth. Neurotrophins have been implicated in a host of brain cellular functions, and in particular, brain-derived neurotrophic factor (BDNF) has a well documented role in development and function of the nervous system. A number of laboratories have reported the effects of TH administration or severe deprivation on neurotrophin expression in brain. This review provides an overview and update of recent developments in the thyroid field as they relate to the nervous system. Secondly, we describe an animal model of low level TH insufficiency that is more relevant for studying the neurological consequences associated with the modest TH perturbations of subclinical hypothyroidism, or that would be anticipated from exposure to environmental contaminants with a mode-of-action that involves the thyroid. Finally, we review the available in vivo literature on TH-mediated alterations in neurotrophins, particularly BDNF, and discuss their possible contribution to brain impairments associated with TH insufficiency. The observations of altered BDNF protein and gene expression have varied as a function of hypothyroid model, age, and brain region assessed. Only a handful of studies have investigated the relationship of neurotrophins and TH using models of TH deprivation that are not severe, and dose-response information is sparse. Differences in the models used, species, doses, regions assessed, age at assessment, and method employed make it difficult to reach a consensus. Based on the available literature, the case for a direct role for BDNF in thyroid-mediated effects in the brain is not compelling. We conclude that delineation of the potential role of neurotrophins in TH-mediated neuronal development may be more fruitful by examining additional neurotrophins (e.g., nerve growth factor), moderate degrees of TH insufficiency, and younger ages. We further suggest that investigation of BDNF invoked by synaptic activation (i.e., plasticity, enrichment, trauma) may serve to elucidate a role of thyroid hormone in BDNF-regulated synaptic function.
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Affiliation(s)
- M E Gilbert
- Toxicity Assessment Division, Neurotoxicology Branch, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA.
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Zhang L, Teng W, Liu Y, Li J, Mao J, Fan C, Wang H, Zhang H, Shan Z. Effect of maternal excessive iodine intake on neurodevelopment and cognitive function in rat offspring. BMC Neurosci 2012; 13:121. [PMID: 23043431 PMCID: PMC3479063 DOI: 10.1186/1471-2202-13-121] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 10/04/2012] [Indexed: 12/20/2022] Open
Abstract
Background Iodine deficiency and iodine excess are both associated with adverse health consequences. Iodine deficiency during pregnancy leads to insufficient maternal thyroid hormone, subsequently causing irreversible adverse effects on the neurological and cognitive functions of the offspring. The results of our previous epidemiological study suggested that mild iodine excess might increase the prevalence of subclinical hypothyroidism. In the present study, female Wistar rats maintained on low-iodine grain were randomly assigned to three groups based on iodated water concentration: low iodine (LI, 1.2 μg/d), normal iodine (NI, 5–6 μg/d), and 3-fold high iodine (3HI, 15–16 μg/d). The present study investigated whether higher-than-normal iodine intake (3HI) by rats from before pregnancy until breastfeeding affects the postnatal (PN) neurodevelopment (PN7 and PN45) of their offspring during particularly sensitive periods in brain development. Results After 12 weeks of treatment (before pregnancy), iodine concentrations in urine and thyroid tissue and circulating thyroxine of adult females correlated with iodine intake. Brain-derived neurotrophic factor (BDNF) expression in the hippocampi of pups on PN7 and PN45 was decreased in 3HI group compared to the NI controls (P < 0.05, all) On PN7 and PN45, the BDNF levels of the 3HI pups were 83.5% and 88.8%, respectively, that of the NI pups. In addition, the 3HI group had a higher neuroendocrine-specific protein A (NSP-A) level than the NI controls on PN7 (P < 0.05). NSP-A levels of the 3HI pups were 117.0% that of the NI pups. No significant difference was observed in the expressions of c-Fos or c-Jun in the hippocampal CA1 region of the 3HI group compared to the controls (P > 0.05). Results from the Morris water maze test revealed that pups of the 3HI group had mild learning and spatial memory deficits. Conclusions The neurodevelopmental and cognitive deficits of the 3HI pups were mild and temporary, likely related to the changes in hippocampal protein expressions of BDNF and NSP-A.
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Affiliation(s)
- Le Zhang
- Department of Endocrinology and Metabolism, First Affiliated Hospital of China Medical University, Shenyang 110001, People's Republic of China
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Lu L, Yu X, Teng W, Shan Z. Treatment with levothyroxine in pregnant rats with subclinical hypothyroidism improves cell migration in the developing brain of the progeny. J Endocrinol Invest 2012; 35:490-6. [PMID: 22024639 DOI: 10.3275/7967] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM This study aims to investigate whether maternal subclinical hypothyroidism (SCH) influences the developing brain, and the effect of treatment with levothyroxine (L-T4) in early maternal SCH on the progeny's developing brain. MATERIALS AND METHODS Seventy-five thyroidectomized female Wistar rats were divided randomly into groups of hypothyroidism (CH), SCH, SCH treated with L-T4 from embryonic day (E) 10, E13, and E17 till post-natal day 21. There were 15 sham operated controls. RESULTS Pups from SCH or CH group had significantly lower body weight than euthyroid group. Pups from E10, E13 or E17 groups had normal body weight compared to control pups at P3 and P7. The levels of TSH and total T4 (TT4) of all pups were normal. The mean latencies were longer in pups from CH, SCH, and E17 group than controls. The latencies from E10 and E13 pups were comparable to those from control pups. There were changes in the cytoarchitecture of the barrel cortex and of the hippocampus in CH, SCH, and E17 pups. The barrel cortex of E10 or E13 pups was similar to that of control pups. The distribution of bromodeoxyuridinelabeled cells was more widespread in CH, SCH, and E17 pups than in control, E10, and E13 progeny. CONCLUSIONS Maternal SCH disturbs learning and memory performances in pups, and affects cytoarchitecture and cell migration in the developing brain of the progeny. Treatment with L-T4 in early maternal SCH before E13 improves cell migration in the developing brain, as well as learning and memory function of the progeny.
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Affiliation(s)
- L Lu
- Department of Endocrinology and Metabolism, the First Hospital of China Medical University, No. 155 Nanjing Bei Street, Heping District, Shenyang, 110001 China
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Abstract
PURPOSE OF REVIEW Survival for the extremely low gestational age neonate (ELGAN; 24-28 weeks) has risen to more than 80%. This extraordinary achievement is tempered by the persistence of cognitive delays and cerebral palsy (CP) affecting nearly one in eight survivors, and requiring subsequent rehabilitative services. A major priority in newborn medicine must be to translate the gains in survival achieved over the past 40 years into gains in healthy survival without the current high frequency of impairments. RECENT FINDINGS Transient hypothyroxinemia in ELGANs is strongly associated with lower IQ scores, behavioral abnormalities and CP. Limited evidence suggests the possibility of a benefit from hormone replacement therapy, but the optimal trial has yet to be conducted. A continuous infusion of 4 μg/kg per day thyroxine for 42 days can safely correct transient hypothyroxinemia without markedly lowering thyroid stimulating hormone levels, thus creating a biochemical euthyroid state. Whether this treatment will make an impact on long-term outcomes is not yet known. SUMMARY With 25 000 neonates born in less than 28 weeks each year in the USA, the economic impact of the very high rates of cognitive disabilities and related neurological dysfunction in survivors is substantial. The lifetime direct and indirect costs of CP are estimated at US$1 million per person and the costs of mental retardation are even higher. If reversal of transient hypothyroxinemia proves effective in reducing the risks of CP or mental retardation in ELGANs by 30%, we estimate an overall saving of US$ 3 billion per year. There is a pressing need for a phase III trial of thyroid hormone that is of sufficient duration and size to determine whether a clinically important reduction in risk of developmental impairments in ELGANs can be achieved.
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