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Maivizhi SM, Sahoo B, Nayak MK. Congenital Hypothyroidism with Neuronal Migration Anomaly. Neurol India 2024; 72:462-463. [PMID: 38817186 DOI: 10.4103/neurol-india.neurol-india-d-24-00195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 03/28/2024] [Indexed: 06/01/2024]
Affiliation(s)
- Shruthi M Maivizhi
- Department of Radiodiagnosis, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
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Kvergelidze E, Barbakadze T, Bátor J, Kalandadze I, Mikeladze D. Thyroid hormone T3 induces Fyn modification and modulates palmitoyltransferase gene expression through αvβ3 integrin receptor in PC12 cells during hypoxia. Transl Neurosci 2024; 15:20220347. [PMID: 39118829 PMCID: PMC11306964 DOI: 10.1515/tnsci-2022-0347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 06/23/2024] [Accepted: 07/08/2024] [Indexed: 08/10/2024] Open
Abstract
Thyroid hormones (THs) are essential in neuronal and glial cell development and differentiation, synaptogenesis, and myelin sheath formation. In addition to nuclear receptors, TH acts through αvβ3-integrin on the plasma membrane, influencing transcriptional regulation of signaling proteins that, in turn, affect adhesion and survival of nerve cells in various neurologic disorders. TH exhibits protective properties during brain hypoxia; however, precise intracellular mechanisms responsible for the preventive effects of TH remain unclear. In this study, we investigated the impact of TH on integrin αvβ3-dependent downstream systems in normoxic and hypoxic conditions of pheochromocytoma PC12 cells. Our findings reveal that triiodothyronine (T3), acting through αvβ3-integrin, induces activation of the JAK2/STAT5 pathway and suppression of the SHP2 in hypoxic PC12 cells. This activation correlates with the downregulation of the expression palmitoyltransferase-ZDHHC2 and ZDHHC9 genes, leading to a subsequent decrease in palmitoylation and phosphorylation of Fyn tyrosine kinase. We propose that these changes may occur due to STAT5-dependent epigenetic silencing of the palmitoyltransferase gene, which in turn reduces palmitoylation/phosphorylation of Fyn with a subsequent increase in the survival of cells. In summary, our study provides the first evidence demonstrating the involvement of integrin-dependent JAK/STAT pathway, SHP2 suppression, and altered post-translational modification of Fyn in protective effects of T3 during hypoxia.
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Affiliation(s)
- Elisabed Kvergelidze
- Faculty of Natural Sciences and Medicine, Ilia State University, Tbilisi, 0162, Georgia
| | - Tamar Barbakadze
- Faculty of Natural Sciences and Medicine, Ilia State University, Tbilisi, 0162, Georgia
- Laboratory of Biochemistry, Ivane Beritashvili Center of Experimental Biomedicine, Tbilisi, 0160, Georgia
| | - Judit Bátor
- Department of Medical Biology and Central Electron Microscopic Laboratory, Medical School, University of Pécs, Pécs, 7624, Hungary
- Janos Szentagothai Research Centre, University of Pécs, Pécs, 7624, Hungary
| | - Irine Kalandadze
- Laboratory of Biochemistry, Ivane Beritashvili Center of Experimental Biomedicine, Tbilisi, 0160, Georgia
| | - David Mikeladze
- Faculty of Natural Sciences and Medicine, Ilia State University, Tbilisi, 0162, Georgia
- Laboratory of Biochemistry, Ivane Beritashvili Center of Experimental Biomedicine, Tbilisi, 0160, Georgia
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3
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Monko TR, Tripp EH, Burr SE, Gunderson KN, Lanier LM, Georgieff MK, Bastian TW. Cellular Iron Deficiency Disrupts Thyroid Hormone Regulated Gene Expression in Developing Hippocampal Neurons. J Nutr 2024; 154:49-59. [PMID: 37984740 PMCID: PMC10808837 DOI: 10.1016/j.tjnut.2023.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/06/2023] [Accepted: 11/03/2023] [Indexed: 11/22/2023] Open
Abstract
BACKGROUND Developing neurons have high thyroid hormone and iron requirements to support their metabolically demanding growth. Early-life iron and thyroid-hormone deficiencies are prevalent and often coexist, and each independently increases risk of permanently impaired neurobehavioral function in children. Early-life dietary iron deficiency reduces thyroid-hormone concentrations and impairs thyroid hormone-responsive gene expression in the neonatal rat brain, but it is unclear whether the effect is cell-intrinsic. OBJECTIVES This study determined whether neuronal-specific iron deficiency alters thyroid hormone-regulated gene expression in developing neurons. METHODS Iron deficiency was induced in primary mouse embryonic hippocampal neuron cultures with the iron chelator deferoxamine (DFO) beginning at 3 d in vitro (DIV). At 11DIV and 18DIV, thyroid hormone-regulated gene messenger ribonucleic acid (mRNA)concentrations indexing thyroid hormone homeostasis (Hairless, mu-crystallin, Type II deiodinase, solute carrier family member 1c1, and solute carrier family member 16a2) and neurodevelopment (neurogranin, Parvalbumin, and Krüppel-like factor 9) were quantified. To assess the effect of iron repletion, DFO was removed at 14DIV from a subset of DFO-treated cultures, and gene expression and adenosine 5'-triphosphate (ATP) concentrations were quantified at 21DIV. RESULTS At 11DIV and 18DIV, neuronal iron deficiency decreased neurogranin, Parvalbumin, and mu-crystallin, and by 18DIV, solute carrier family member 16a2, solute carrier family member 1c1, Type II deiodinase, and Hairless were increased, suggesting cellular sensing of a functionally abnormal thyroid hormone state. Dimensionality reduction with Principal component analysis reveals that thyroid hormone homeostatic genes strongly correlate with and predict iron status. Iron repletion from 14-21DIV did not restore ATP concentration, and Principal component analysis suggests that, after iron repletion, cultures maintain a gene expression signature indicative of previous iron deficiency. CONCLUSIONS These novel findings suggest there is an intracellular mechanism coordinating cellular iron/thyroid hormone activities. We speculate this is a part of the homeostatic response to acutely match neuronal energy production and growth signaling. However, the adaptation to iron deficiency may cause permanent deficits in thyroid hormone-dependent neurodevelopmental processes even after recovery from iron deficiency.
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Affiliation(s)
- Timothy R Monko
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Emma H Tripp
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Sierra E Burr
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Karina N Gunderson
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Lorene M Lanier
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Michael K Georgieff
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Thomas W Bastian
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota.
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de Souza JS. Thyroid hormone biosynthesis and its role in brain development and maintenance. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 142:329-365. [PMID: 39059990 DOI: 10.1016/bs.apcsb.2023.12.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Thyroid hormones are critical modulators in the physiological processes necessary to virtually all tissues, with exceptionally fundamental roles in brain development and maintenance. These hormones regulate essential neurodevelopment events, including neuronal migration, synaptogenesis, and myelination. Additionally, thyroid hormones are crucial for maintaining brain homeostasis and cognitive function in adulthood. This chapter aims to offer a comprehensive understanding of thyroid hormone biosynthesis and its intricate role in brain physiology. Here, we described the mechanisms underlying the biosynthesis of thyroid hormones, their influence on various aspects of brain development and ongoing maintenance, and the proteins in the brain that are responsive to these hormones. This chapter was geared towards broadening our understanding of thyroid hormone action in the brain, shedding light on potential therapeutic targets for neurodevelopmental and neurodegenerative disorders.
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Affiliation(s)
- Janaina Sena de Souza
- Department of Pediatrics and Cellular & Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, CA, United States.
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5
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Fame RM, Kalugin PN, Petrova B, Xu H, Soden PA, Shipley FB, Dani N, Grant B, Pragana A, Head JP, Gupta S, Shannon ML, Chifamba FF, Hawks-Mayer H, Vernon A, Gao F, Zhang Y, Holtzman MJ, Heiman M, Andermann ML, Kanarek N, Lipton JO, Lehtinen MK. Defining diurnal fluctuations in mouse choroid plexus and CSF at high molecular, spatial, and temporal resolution. Nat Commun 2023; 14:3720. [PMID: 37349305 PMCID: PMC10287727 DOI: 10.1038/s41467-023-39326-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 06/07/2023] [Indexed: 06/24/2023] Open
Abstract
Transmission and secretion of signals via the choroid plexus (ChP) brain barrier can modulate brain states via regulation of cerebrospinal fluid (CSF) composition. Here, we developed a platform to analyze diurnal variations in male mouse ChP and CSF. Ribosome profiling of ChP epithelial cells revealed diurnal translatome differences in metabolic machinery, secreted proteins, and barrier components. Using ChP and CSF metabolomics and blood-CSF barrier analyses, we observed diurnal changes in metabolites and cellular junctions. We then focused on transthyretin (TTR), a diurnally regulated thyroid hormone chaperone secreted by the ChP. Diurnal variation in ChP TTR depended on Bmal1 clock gene expression. We achieved real-time tracking of CSF-TTR in awake TtrmNeonGreen mice via multi-day intracerebroventricular fiber photometry. Diurnal changes in ChP and CSF TTR levels correlated with CSF thyroid hormone levels. These datasets highlight an integrated platform for investigating diurnal control of brain states by the ChP and CSF.
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Affiliation(s)
- Ryann M Fame
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Department of Neurosurgery, Stanford University, Stanford, CA, 94305, USA
| | - Peter N Kalugin
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Graduate Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Harvard/MIT MD-PhD Program, Harvard Medical School, Boston, MA, 02115, USA
| | - Boryana Petrova
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Huixin Xu
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Paul A Soden
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Frederick B Shipley
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Graduate Program in Biophysics, Harvard University, Cambridge, MA, 02138, USA
| | - Neil Dani
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Bradford Grant
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Aja Pragana
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Joshua P Head
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Suhasini Gupta
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Morgan L Shannon
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Fortunate F Chifamba
- Department of Neurology and the F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Hannah Hawks-Mayer
- Department of Neurology and the F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Amanda Vernon
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Picower Institute for Learning and Memory, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Fan Gao
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Picower Institute for Learning and Memory, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Lyterian Therapeutics, South San Francisco, 94080, CA, USA
| | - Yong Zhang
- Pulmonary and Critical Care Medicine, Department of Medicine, Washington University, St. Louis, MO, 63110, USA
| | - Michael J Holtzman
- Pulmonary and Critical Care Medicine, Department of Medicine, Washington University, St. Louis, MO, 63110, USA
| | - Myriam Heiman
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Picower Institute for Learning and Memory, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Mark L Andermann
- Graduate Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA
- Graduate Program in Biophysics, Harvard University, Cambridge, MA, 02138, USA
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, 02115, USA
| | - Naama Kanarek
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jonathan O Lipton
- Department of Neurology and the F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, 02115, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Maria K Lehtinen
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
- Graduate Program in Neuroscience, Harvard Medical School, Boston, MA, 02115, USA.
- Graduate Program in Biophysics, Harvard University, Cambridge, MA, 02138, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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Monko TR, Tripp EH, Burr SE, Gunderson KN, Lanier LM, Georgieff MK, Bastian TW. Cellular Iron Deficiency Disrupts Thyroid Hormone Regulated Gene Expression in Developing Hippocampal Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.17.545408. [PMID: 37398002 PMCID: PMC10312787 DOI: 10.1101/2023.06.17.545408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Background Developing neurons have high thyroid hormone and iron requirements to support their metabolism and growth. Early-life iron and thyroid hormone deficiencies are prevalent, often coexist, and increase the risk of permanently impaired neurobehavioral function in children. Early-life dietary iron deficiency reduces thyroid hormone levels and impairs thyroid hormone-responsive gene expression in the neonatal rat brain. Objective This study determined whether neuronal-specific iron deficiency alters thyroid hormone-regulated gene expression in developing neurons. Methods Iron deficiency was induced in primary mouse embryonic hippocampal neuron cultures with the iron chelator deferoxamine (DFO) beginning at 3 days in vitro (DIV). At 11DIV and 18DIV, mRNA levels for thyroid hormone-regulated genes indexing thyroid hormone homeostasis (Hr, Crym, Dio2, Slco1c1, Slc16a2) and neurodevelopment (Nrgn, Pvalb, Klf9) were quantified. To assess the effect of iron repletion, DFO was removed at 14DIV from a subset of DFO-treated cultures and gene expression and ATP levels were quantified at 21DIV. Results At 11DIV and 18DIV, neuronal iron deficiency decreased Nrgn, Pvalb, and Crym, and by 18DIV, Slc16a2, Slco1c1, Dio2, and Hr were increased; collectively suggesting cellular sensing of a functionally abnormal thyroid hormone state. Dimensionality reduction with Principal Component Analysis (PCA) reveals that thyroid hormone homeostatic genes strongly correlate with and predict iron status (Tfr1 mRNA). Iron repletion from 14-21DIV restored neurodevelopmental genes, but not all thyroid hormone homeostatic genes, and ATP concentrations remained significantly altered. PCA clustering suggests that cultures replete with iron maintain a gene expression signature indicative of previous iron deficiency. Conclusions These novel findings suggest there is an intracellular mechanism coordinating cellular iron/thyroid hormone activities. We speculate this is a part of homeostatic response to match neuronal energy production and growth signaling for these important metabolic regulators. However, iron deficiency may cause permanent deficits in thyroid hormone-dependent neurodevelopmental processes even after recovery from iron deficiency.
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Affiliation(s)
- Timothy R Monko
- University of Minnesota, School of Medicine, Department of Pediatrics
| | - Emma H Tripp
- University of Minnesota, School of Medicine, Department of Pediatrics
| | - Sierra E Burr
- University of Minnesota, School of Medicine, Department of Pediatrics
| | | | | | | | - Thomas W Bastian
- University of Minnesota, School of Medicine, Department of Pediatrics
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Xie H, Chen D, Gu W, Li W, Wang X, Tang W. Thyroid function screening and follow-up of children with abdominal distension in Nanjing, China: a cross-sectional study. BMJ Open 2023; 13:e070416. [PMID: 36697039 PMCID: PMC9884940 DOI: 10.1136/bmjopen-2022-070416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE To describe the thyroid function test among children with abdominal distention and to follow up the treatment received by children with abnormal thyroid function. DESIGN Cross-sectional study. SETTING AND PARTICIPANTS A total of 1089 children (median age:30 days (IQR=21-60 days) with abdominal distension were included in this single centre study in Nanjing, China. RESULT Thyroid dysfunction was found in 43 of 148 Hirschsprung's disease (HSCR) cases, with 3 (2.03%) having hypothyroidism, 3 (2.03%) having subclinical hypothyroidism and 3 (2.03%) having subclinical hyperthyroidism. Thyroid dysfunction was found in 206 of 941 functional abdominal distension cases, with 4 (0.43%) having hypothyroidism, 23 (2.4%) having subclinical hypothyroidism, 28 (2.9%) having subclinical hyperthyroidism and 1 (0.11%) having hyperthyroidism. Among total 65 cases (9 from HSCR, 56 from functional abdominal distension) diagnosed with thyroid diseases, 12 were treated with levothyroxine (LT-4), of which 9 were discontinued treatment at about 2 years old, and 3 were still receiving LT-4. Thirty-two cases received no treatment and thyroid function returned to normal in about 1 month. Twenty-one cases were lost during the follow-up. CONCLUSION The paediatrician should be vigilant for hypothyroidism when dealing with children with abdominal distension. Thyroid function should be followed up rather than simply administering a short-term levothyroxine treatment.
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Affiliation(s)
- Hang Xie
- Department of Neonatal Surgery, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Dongmei Chen
- Department of Emergency, Pediatric intensive care unit, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Gu
- Department of Quality Management, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Wei Li
- Department of Quality Management, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Xu Wang
- Department of Endocrinology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Weibing Tang
- Department of Neonatal Surgery, Children's Hospital of Nanjing Medical University, Nanjing, China
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Relationship between thyroid hormones and central nervous system metabolism in physiological and pathological conditions. Pharmacol Rep 2022; 74:847-858. [PMID: 35771431 DOI: 10.1007/s43440-022-00377-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 11/08/2022]
Abstract
Thyroid hormones (THs) play an important role in the regulation of energy metabolism. They also take part in processes associated with the central nervous system (CNS), including survival and differentiation of neurons and energy expenditure. It has been reported that a correlation exists between the functioning of the thyroid gland and the symptoms of CNS such as cognitive impairment, depression, and dementia. Literature data also indicate the influence of THs on the pathogenesis of CNS diseases, such as Alzheimer's disease, epilepsy, depression, and Parkinson's disease. This review describes the relationship between THs and metabolism in the CNS, the effect of THs on the pathological conditions of the CNS, and novel options for treating these conditions with TH derivatives.
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Stawerska R, Nowak-Bednarek M, Talar T, Kolasa-Kicińska M, Łupińska A, Hilczer M, Gulczyńska E, Lewiński A. The prevalence of hypothyroxinemia in premature newborns. Front Endocrinol (Lausanne) 2022; 13:940152. [PMID: 36034431 PMCID: PMC9399394 DOI: 10.3389/fendo.2022.940152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 07/19/2022] [Indexed: 11/27/2022] Open
Abstract
Congenital hypothyroidism diagnosed by TSH assessment in bloodspot screening may be overlooked in preterm newborns due to immaturity of the hypothalamus-pituitary-thyroid axis in them. The purpose of the study was to determine the prevalence and causes of hypothyroxinemia in preterm newborns, determined by TSH and FT4 serum concentration measurement, performed on the 3-5th day of life. We assessed TSH, FT4 and FT3 serum concentration on the 3-5th day of life in preterm children born at our centre within three consecutive years. We assessed the incidence of hypothyroxinemia, and its cause: primary hypothyroidism, secondary hypothyroidism or low FT4 syndrome - with normal TSH concentration, its dependence - among others - on gestational age (GA), birth body weight (BBW) and being SGA. A total of 525 preterm children were examined. FT4 concentration was decreased in 14.9% of preterm newborns. The most frequent cause of hypothyroxinemia was low FT4 syndrome (79.5%). More than 92% cases of hypothyroxinemia occurred in children born before the 32nd week and/or with BBW below 1500 g. Thus, every fourth child in these groups had a reduced FT4 concentration. Neonates with hypothyroxinemia were significantly lighter than those with normal FT4. In older and heavier neonates with hypothyroxinemia, serious congenital defects were observed. Neither IVH nor SGA nor twin pregnancies predispose children to hypothyroxinemia. Among newborns with untreated hypothyroxinemia in whom TSH and FT4 assessment was repeated within 2-5 weeks, a decreased FT4 concentration was confirmed in 56.1% of cases. As hypothyroxinemia affects 25% of newborns born before the 32nd week of gestation and those in whom BBW is less than 1500g, it seems that in this group of children the newborn screening should be extended to measure serum TSH and FT4 concentration between the 3-5th day of life. In older and heavier neonates, additional serum TSH and FT4 assessment should be limited to children with severe congenital abnormalities but not to all SGA or twins. Despite the fact that the most common form of preterm hypothyroxinemia is low FT4 syndrome, it should be emphasized that FT4 remains lowered on subsequent testing in more them 50% of cases.
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Affiliation(s)
- Renata Stawerska
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial - Hospital Research Institute, Lodz, Poland
- Department of Paediatric Endocrinology, Medical University of Lodz, Lodz, Poland
| | - Marzena Nowak-Bednarek
- Department of Neonatology, Intensive Therapy and Neonatal Pathology, Polish Mother’s Memorial Hospital – Research Institute, Lodz, Poland
| | - Tomasz Talar
- Department of Neonatology, Intensive Therapy and Neonatal Pathology, Polish Mother’s Memorial Hospital – Research Institute, Lodz, Poland
| | - Marzena Kolasa-Kicińska
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial - Hospital Research Institute, Lodz, Poland
| | - Anna Łupińska
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial - Hospital Research Institute, Lodz, Poland
- Department of Paediatric Endocrinology, Medical University of Lodz, Lodz, Poland
| | - Maciej Hilczer
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial - Hospital Research Institute, Lodz, Poland
| | - Ewa Gulczyńska
- Department of Neonatology, Intensive Therapy and Neonatal Pathology, Polish Mother’s Memorial Hospital – Research Institute, Lodz, Poland
| | - Andrzej Lewiński
- Department of Endocrinology and Metabolic Diseases, Polish Mother’s Memorial - Hospital Research Institute, Lodz, Poland
- Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, Lodz, Poland
- *Correspondence: Andrzej Lewiński,
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