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Ates T, Oncul M, Dilsiz P, Topcu IC, Civas CC, Alp MI, Aklan I, Ates Oz E, Yavuz Y, Yilmaz B, Sayar Atasoy N, Atasoy D. Inactivation of Magel2 suppresses oxytocin neurons through synaptic excitation-inhibition imbalance. Neurobiol Dis 2018; 121:58-64. [PMID: 30240706 DOI: 10.1016/j.nbd.2018.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/03/2018] [Accepted: 09/17/2018] [Indexed: 12/28/2022] Open
Abstract
Prader-Willi and the related Schaaf-Yang Syndromes (PWS/SYS) are rare neurodevelopmental disorders characterized by overlapping phenotypes of high incidence of autism spectrum disorders (ASD) and neonatal feeding difficulties. Based on clinical and basic studies, oxytocin pathway defects are suggested to contribute disease pathogenesis but the mechanism has been poorly understood. Specifically, whether the impairment in oxytocin system is limited to neuropeptide levels and how the functional properties of broader oxytocin neuron circuits affected in PWS/SYS have not been addressed. Using cell type specific electrophysiology, we investigated basic synaptic and cell autonomous properties of oxytocin neurons in the absence of MAGEL2; a hypothalamus enriched ubiquitin ligase regulator that is inactivated in both syndromes. We observed significant suppression of overall ex vivo oxytocin neuron activity, which was largely contributed by altered synaptic input profile; with reduced excitatory and increased inhibitory currents. Our results suggest that dysregulation of oxytocin system goes beyond altered neuropeptide expression and synaptic excitation inhibition imbalance impairs overall oxytocin pathway function.
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Affiliation(s)
- Tayfun Ates
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Merve Oncul
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Pelin Dilsiz
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Iskalen Cansu Topcu
- Department of Physiology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Cihan Civan Civas
- Department of Physiology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Muhammed Ikbal Alp
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Iltan Aklan
- Department of Physiology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Edanur Ates Oz
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Yavuz Yavuz
- Department of Physiology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Bayram Yilmaz
- Department of Physiology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Nilufer Sayar Atasoy
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey
| | - Deniz Atasoy
- Department of Physiology, School of Medicine, Regenerative and Restorative Medical Research Center (REMER), Istanbul Medipol University, Istanbul, Turkey.
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Molecular Mechanisms of Oxytocin Signaling at the Synaptic Connection. Neural Plast 2018; 2018:4864107. [PMID: 30057594 PMCID: PMC6051047 DOI: 10.1155/2018/4864107] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 05/27/2018] [Indexed: 12/12/2022] Open
Abstract
Aberrant regulation of oxytocin signaling is associated with the etiology of neurodevelopmental disorders. Synaptic dysfunctions in neurodevelopmental disorders are becoming increasingly known, and their pathogenic mechanisms could be a target of potential therapeutic intervention. Therefore, it is important to pay attention to the role of oxytocin and its receptor in synapse structure, function, and neuron connectivity. An early alteration in oxytocin signaling may disturb neuronal maturation and may have short-term and long-term pathological consequences. At the molecular level, neurodevelopmental disorders include alterations in cytoskeletal rearrangement and neuritogenesis resulting in a diversity of synaptopathies. The presence of oxytocin receptors in the presynaptic and postsynaptic membranes and the direct effects of oxytocin on neuronal excitability by regulating the activity of ion channels in the cell membrane implicate that alterations in oxytocin signaling could be involved in synaptopathies. The ability of oxytocin to modulate neurogenesis, synaptic plasticity, and certain parameters of cytoskeletal arrangement is discussed in the present review.
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D. Hidalgo-Santos A, del Carmen DeMingo-Alemany M, Moreno-Macián F, Roselló M, Orellana C, Martínez F, Caro-Llopis A, León-Cariñena S, Tomás-Vila M. A Novel Mutation of MAGEL2 in a Patient with Schaaf-Yang Syndrome and Hypopituitarism. Int J Endocrinol Metab 2018; 16:e67329. [PMID: 30323850 PMCID: PMC6176277 DOI: 10.5812/ijem.67329] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 05/09/2018] [Accepted: 06/12/2018] [Indexed: 02/07/2023] Open
Abstract
INTRODUCTION Schaaf-Yang syndrome (SYS) is caused by truncating point mutations of the paternal allele of MAGEL2, an imprinted gene located in the critical region of Prader-Willi syndrome (PWS). These patients present a phenotype with neurodevelopmental delay, hypotonia, joint contractures, and a particularly high prevalence of autism (up to 75% in affected individuals). The loss of function of MAGEL2 is suggested to contribute to endocrine hypothalamic dysfunction in individuals with PWS. CASE PRESENTATION The current study presented the case of a patient with SYS and a novel de novo truncating mutation of MAGEL2 and phenotypic characteristics typical of this Prader-Willi-like syndrome and also including partial hypopituitarism, hypothyroidism, growth hormone deficiency, and hyperprolactinemia. CONCLUSIONS The clinical and molecular similarities between SYS and PWS suggested the need for a thorough endocrinological follow-up to improve the prognosis and long-term quality of life for patients with SYS.
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Affiliation(s)
- Antonio D. Hidalgo-Santos
- Pediatric Endocrinology Section, University and Polytechnic Hospital La Fe, Valencia, Spain
- Corresponding author: Antonio D. Hidalgo-Santos, Avda Fernando Abril Martorell Street 106, 46026, Valencia, Spain. Tel: +34-687164542, E-mail:
| | | | | | - Mónica Roselló
- Department of Clinical Genetics, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Carmen Orellana
- Department of Clinical Genetics, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Francisco Martínez
- Department of Clinical Genetics, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Alfonso Caro-Llopis
- Department of Clinical Genetics, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Sara León-Cariñena
- Pediatric Endocrinology Section, University and Polytechnic Hospital La Fe, Valencia, Spain
| | - Miguel Tomás-Vila
- Neuropediatric Section, University and Polytechnic Hospital La Fe, Valencia, Spain
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Jobling R, Stavropoulos DJ, Marshall CR, Cytrynbaum C, Axford MM, Londero V, Moalem S, Orr J, Rossignol F, Lopes FD, Gauthier J, Alos N, Rupps R, McKinnon M, Adam S, Nowaczyk MJM, Walker S, Scherer SW, Nassif C, Hamdan FF, Deal CL, Soucy JF, Weksberg R, Macleod P, Michaud JL, Chitayat D. Chitayat-Hall and Schaaf-Yang syndromes:a common aetiology: expanding the phenotype of MAGEL2-related disorders. J Med Genet 2018; 55:316-321. [DOI: 10.1136/jmedgenet-2017-105222] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 03/02/2018] [Accepted: 03/11/2018] [Indexed: 12/21/2022]
Abstract
BackgroundChitayat-Hall syndrome, initially described in 1990, is a rare condition characterised by distal arthrogryposis, intellectual disability, dysmorphic features and hypopituitarism, in particular growth hormone deficiency. The genetic aetiology has not been identified.Methods and resultsWe identified three unrelated families with a total of six affected patients with the clinical manifestations of Chitayat-Hall syndrome. Through whole exome or whole genome sequencing, pathogenic variants in the MAGEL2 gene were identified in all affected patients. All disease-causing sequence variants detected are predicted to result in a truncated protein, including one complex variant that comprised a deletion and inversion.ConclusionsChitayat-Hall syndrome is caused by pathogenic variants in MAGEL2 and shares a common aetiology with the recently described Schaaf-Yang syndrome. The phenotype of MAGEL2-related disorders is expanded to include growth hormone deficiency as an important and treatable complication.
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