1
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McArdle CJ, Arnone AA, Heaney CF, Raab-Graham KF. A paradoxical switch: the implications of excitatory GABAergic signaling in neurological disorders. Front Psychiatry 2024; 14:1296527. [PMID: 38268565 PMCID: PMC10805837 DOI: 10.3389/fpsyt.2023.1296527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 12/04/2023] [Indexed: 01/26/2024] Open
Abstract
Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the central nervous system. In the mature brain, inhibitory GABAergic signaling is critical in maintaining neuronal homeostasis and vital human behaviors such as cognition, emotion, and motivation. While classically known to inhibit neuronal function under physiological conditions, previous research indicates a paradoxical switch from inhibitory to excitatory GABAergic signaling that is implicated in several neurological disorders. Various mechanisms have been proposed to contribute to the excitatory switch such as chloride ion dyshomeostasis, alterations in inhibitory receptor expression, and modifications in GABAergic synaptic plasticity. Of note, the hypothesized mechanisms underlying excitatory GABAergic signaling are highlighted in a number of neurodevelopmental, substance use, stress, and neurodegenerative disorders. Herein, we present an updated review discussing the presence of excitatory GABAergic signaling in various neurological disorders, and their potential contributions towards disease pathology.
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Affiliation(s)
- Colin J. McArdle
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Alana A. Arnone
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
- Department of General Surgery, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Chelcie F. Heaney
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Kimberly F. Raab-Graham
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
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2
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Comas M, De Pietri Tonelli D, Berdondini L, Astiz M. Ontogeny of the circadian system: a multiscale process throughout development. Trends Neurosci 2024; 47:36-46. [PMID: 38071123 DOI: 10.1016/j.tins.2023.11.004] [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: 07/23/2023] [Revised: 10/02/2023] [Accepted: 11/12/2023] [Indexed: 01/12/2024]
Abstract
The 24 h (circadian) timing system develops in mammals during the perinatal period. It carries out the essential task of anticipating daily recurring environmental changes to identify the best time of day for each molecular, cellular, and systemic process. Although significant knowledge has been acquired about the organization and function of the adult circadian system, relatively little is known about its ontogeny. During the perinatal period, the circadian system progressively gains functionality under the influence of the early environment. This review explores current evidence on the development of the circadian clock in mammals, highlighting the multilevel complexity of the process and the importance of gaining a better understanding of its underlying biology.
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Affiliation(s)
- Maria Comas
- Circadian Physiology of Neurons and Glia Laboratory, Achucarro Basque Center for Neuroscience, 48940 Leioa, Basque Country, Spain
| | | | - Luca Berdondini
- Microtechnology for Neuroelectronics, Fondazione Istituto Italiano di Tecnologia (IIT), 16163 Genova, Italy
| | - Mariana Astiz
- Circadian Physiology of Neurons and Glia Laboratory, Achucarro Basque Center for Neuroscience, 48940 Leioa, Basque Country, Spain; Ikerbasque - Basque Foundation for Science, Bilbao, Spain; Institute of Neurobiology, University of Lübeck, 23562 Lübeck, Germany.
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3
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Peall KJ, Owen MJ, Hall J. Rare genetic brain disorders with overlapping neurological and psychiatric phenotypes. Nat Rev Neurol 2024; 20:7-21. [PMID: 38001363 DOI: 10.1038/s41582-023-00896-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2023] [Indexed: 11/26/2023]
Abstract
Understanding rare genetic brain disorders with overlapping neurological and psychiatric phenotypes is of increasing importance given the potential for developing disease models that could help to understand more common, polygenic disorders. However, the traditional clinical boundaries between neurology and psychiatry result in frequent segregation of these disorders into distinct silos, limiting cross-specialty understanding that could facilitate clinical and biological advances. In this Review, we highlight multiple genetic brain disorders in which neurological and psychiatric phenotypes are observed, but for which in-depth, cross-spectrum clinical phenotyping is rarely undertaken. We describe the combined phenotypes observed in association with genetic variants linked to epilepsy, dystonia, autism spectrum disorder and schizophrenia. We also consider common underlying mechanisms that centre on synaptic plasticity, including changes to synaptic and neuronal structure, calcium handling and the balance of excitatory and inhibitory neuronal activity. Further investigation is needed to better define and replicate these phenotypes in larger cohorts, which would help to gain greater understanding of the pathophysiological mechanisms and identify common therapeutic targets.
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Affiliation(s)
- Kathryn J Peall
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK.
- Division of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK.
| | - Michael J Owen
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK
- Division of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK
- Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
| | - Jeremy Hall
- Neuroscience and Mental Health Innovation Institute, Cardiff University, Cardiff, UK
- Division of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK
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4
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Ikrin AN, Moskalenko AM, Mukhamadeev RR, de Abreu MS, Kolesnikova TO, Kalueff AV. The emerging complexity of molecular pathways implicated in mouse self-grooming behavior. Prog Neuropsychopharmacol Biol Psychiatry 2023; 127:110840. [PMID: 37580009 DOI: 10.1016/j.pnpbp.2023.110840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/29/2023] [Accepted: 08/11/2023] [Indexed: 08/16/2023]
Abstract
Rodent self-grooming is an important complex behavior, and its deficits are translationally relevant to a wide range of neuropsychiatric disorders. Here, we analyzed a comprehensive dataset of 227 genes whose mutations are known to evoke aberrant self-grooming in mice. Using these genes, we constructed the network of their established protein-protein interactions (PPI), yielding several distinct molecular clusters related to postsynaptic density, the Wnt signaling, transcription factors, neuronal cell cycle, NOS neurotransmission, microtubule regulation, neuronal differentiation/trafficking, neurodevelopment and mitochondrial function. Utilizing further bioinformatics analyses, we also identified novel central ('hub') proteins within these clusters, whose genes may also be implicated in aberrant self-grooming and other repetitive behaviors in general. Untangling complex molecular pathways of this important behavior using in silico approaches contributes to our understanding of related neurological disorders, and may suggest novel potential targets for their pharmacological or gene therapy.
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Affiliation(s)
- Aleksey N Ikrin
- Graduate Program in Genetics and Genetic Technologies, Sirius University of Science and Technology, Sochi 354340, Russia; Neuroscience Department, Sirius University of Science and Technology, Sochi 354340, Russia
| | - Anastasia M Moskalenko
- Graduate Program in Genetics and Genetic Technologies, Sirius University of Science and Technology, Sochi 354340, Russia; Neuroscience Department, Sirius University of Science and Technology, Sochi 354340, Russia
| | - Radmir R Mukhamadeev
- Graduate Program in Bioinformatics and Genomics, Sirius University of Science and Technology, Sochi 354340, Russia; Neuroscience Department, Sirius University of Science and Technology, Sochi 354340, Russia
| | - Murilo S de Abreu
- Moscow Institute of Science and Technology, Dolgoprudny 197028, Russia.
| | - Tatiana O Kolesnikova
- Neuroscience Department, Sirius University of Science and Technology, Sochi 354340, Russia
| | - Allan V Kalueff
- Neuroscience Department, Sirius University of Science and Technology, Sochi 354340, Russia; Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg 199034, Russia; Institute of Experimental Medicine, Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, St. Petersburg 194021, Russia; Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, Pesochny 197758, Russia; Neuroscience Group, Ural Federal University, Ekaterinburg 620002, Russia; Laboratory of Translational Biopsychiatry, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk 630117, Russia.
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5
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Odabasi Y, Yanasik S, Saglam-Metiner P, Kaymaz Y, Yesil-Celiktas O. Comprehensive Transcriptomic Investigation of Rett Syndrome Reveals Increasing Complexity Trends from Induced Pluripotent Stem Cells to Neurons with Implications for Enriched Pathways. ACS OMEGA 2023; 8:44148-44162. [PMID: 38027357 PMCID: PMC10666228 DOI: 10.1021/acsomega.3c06448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/19/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
Rett syndrome (RTT) is a rare genetic neurodevelopmental disorder that has no cure apart from symptomatic treatments. While intense research efforts are required to fulfill this unmet need, the fundamental challenge is to obtain sufficient patient data. In this study, we used human transcriptomic data of four different sample types from RTT patients including induced pluripotent stem cells, differentiated neural progenitor cells, differentiated neurons, and postmortem brain tissues with an increasing in vivo-like complexity to unveil specific trends in gene expressions across the samples. Based on DEG analysis, we identified F8A3, CNTN6, RPE65, and COL19A1 to have differential expression levels in three sample types and also observed previously reported genes such as MECP2, FOXG1, CACNA1G, SATB2, GABBR2, MEF2C, KCNJ10, and CUX2 in our study. Considering the significantly enriched pathways for each sample type, we observed a consistent increase in numbers from iPSCs to NEUs where MECP2 displayed profound effects. We also validated our GSEA results by using single-cell RNA-seq data. In WGCNA, we elicited a connection among MECP2, TNRC6A, and HOXA5. Our findings highlight the utility of transcriptomic analyses to determine genes that might lead to therapeutic strategies.
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Affiliation(s)
- Yusuf
Caglar Odabasi
- Department of Bioengineering,
Faculty of Engineering, Ege University, Izmir 35100, Turkey
| | - Sena Yanasik
- Department of Bioengineering,
Faculty of Engineering, Ege University, Izmir 35100, Turkey
| | - Pelin Saglam-Metiner
- Department of Bioengineering,
Faculty of Engineering, Ege University, Izmir 35100, Turkey
| | - Yasin Kaymaz
- Department of Bioengineering,
Faculty of Engineering, Ege University, Izmir 35100, Turkey
| | - Ozlem Yesil-Celiktas
- Department of Bioengineering,
Faculty of Engineering, Ege University, Izmir 35100, Turkey
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6
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Peerboom C, de Kater S, Jonker N, Rieter MPJM, Wijne T, Wierenga CJ. Delaying the GABA Shift Indirectly Affects Membrane Properties in the Developing Hippocampus. J Neurosci 2023; 43:5483-5500. [PMID: 37438107 PMCID: PMC10376938 DOI: 10.1523/jneurosci.0251-23.2023] [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: 02/10/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/14/2023] Open
Abstract
During the first two postnatal weeks, intraneuronal chloride concentrations in rodents gradually decrease, causing a shift from depolarizing to hyperpolarizing GABA responses. The postnatal GABA shift is delayed in rodent models for neurodevelopmental disorders and in human patients, but the impact of a delayed GABA shift on the developing brain remains obscure. Here we examine the direct and indirect consequences of a delayed postnatal GABA shift on network development in organotypic hippocampal cultures made from 6- to 7-d-old mice by treating the cultures for 1 week with VU0463271, a specific inhibitor of the chloride exporter KCC2. We verified that VU treatment delayed the GABA shift and kept GABA signaling depolarizing until DIV9. We found that the structural and functional development of excitatory and inhibitory synapses at DIV9 was not affected after VU treatment. In line with previous studies, we observed that GABA signaling was already inhibitory in control and VU-treated postnatal slices. Surprisingly, 14 d after the VU treatment had ended (DIV21), we observed an increased frequency of spontaneous inhibitory postsynaptic currents in CA1 pyramidal cells, while excitatory currents were not changed. Synapse numbers and release probability were unaffected. We found that dendrite-targeting interneurons in the stratum radiatum had an elevated resting membrane potential, while pyramidal cells were less excitable compared with control slices. Our results show that depolarizing GABA signaling does not promote synapse formation after P7, and suggest that postnatal intracellular chloride levels indirectly affect membrane properties in a cell-specific manner.SIGNIFICANCE STATEMENT During brain development, the action of neurotransmitter GABA shifts from depolarizing to hyperpolarizing. This shift is a thought to play a critical role in synapse formation. A delayed shift is common in rodent models for neurodevelopmental disorders and in human patients, but its consequences for synaptic development remain obscure. Here, we delayed the GABA shift by 1 week in organotypic hippocampal cultures and carefully examined the consequences for circuit development. We find that delaying the shift has no direct effects on synaptic development, but instead leads to indirect, cell type-specific changes in membrane properties. Our data call for careful assessment of alterations in cellular excitability in neurodevelopmental disorders.
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Affiliation(s)
- Carlijn Peerboom
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Sam de Kater
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Nikki Jonker
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Marijn P J M Rieter
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Tessel Wijne
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Corette J Wierenga
- Cell Biology, Neurobiology and Biophysics, Biology Department, Utrecht University, Utrecht, 3584 CH, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, 6525 AJ, The Netherlands
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7
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Oluigbo DC. Rett Syndrome: A Tale of Altered Genetics, Synaptic Plasticity, and Neurodevelopmental Dynamics. Cureus 2023; 15:e41555. [PMID: 37554594 PMCID: PMC10405636 DOI: 10.7759/cureus.41555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2023] [Indexed: 08/10/2023] Open
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder that is a leading cause of severe cognitive and physical impairment. RTT typically occurs in females, although rare cases of males with the disease exist. Its genetic cause, symptoms, and clinical progression timeline have also become well-documented since its initial discovery. However, a relatively late diagnosis and lack of an available cure signify that our understanding of the disease is incomplete. Innovative research methods and tools are thereby helping to fill gaps in our knowledge of RTT. Specifically, mouse models of RTT, video analysis, and retrospective parental analysis are well-established tools that provide valuable insights into RTT. Moreover, current and anticipated treatment options are improving the quality of life of the RTT patient population. Collectively, these developments are creating optimistic future perspectives for RTT.
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Affiliation(s)
- David C Oluigbo
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, USA
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8
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Belaïdouni Y, Diabira D, Brosset-Heckel M, Valsamides V, Graziano JC, Santos C, Menuet C, Wayman GA, Gaiarsa JL. Leptin antagonism improves Rett syndrome phenotype in symptomatic male Mecp2-null mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.03.526251. [PMID: 36778454 PMCID: PMC9915649 DOI: 10.1101/2023.02.03.526251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder that arise from de novo mutations in the X-linked gene MECP2 (methyl-CpG-binding protein 2). Circulating levels of the adipocyte hormone leptin are elevated in RTT patients and rodent models of the disease. Leptin targets a large number of brain structures and regulates a wide range of developmental and physiological functions which are altered in RTT. We hypothesized that elevated leptin levels might contribute to RTT pathogenesis. Accordingly, we show that pharmacological antagonism of leptin or genetic reduction of leptin production prevents the degradation of health status, weight loss and the progression of breathing and locomotor deficits. At the neuronal level, the anti-leptin strategies rescue the hippocampal excitatory/inhibitory imbalance and synaptic plasticity impairment. Targeting leptin might therefore represent a new approach for RTT treatment.
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9
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Purushotham SS, Reddy NMN, D'Souza MN, Choudhury NR, Ganguly A, Gopalakrishna N, Muddashetty R, Clement JP. A perspective on molecular signalling dysfunction, its clinical relevance and therapeutics in autism spectrum disorder. Exp Brain Res 2022; 240:2525-2567. [PMID: 36063192 DOI: 10.1007/s00221-022-06448-x] [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: 06/01/2022] [Accepted: 08/18/2022] [Indexed: 11/29/2022]
Abstract
Intellectual disability (ID) and autism spectrum disorder (ASD) are neurodevelopmental disorders that have become a primary clinical and social concern, with a prevalence of 2-3% in the population. Neuronal function and behaviour undergo significant malleability during the critical period of development that is found to be impaired in ID/ASD. Human genome sequencing studies have revealed many genetic variations associated with ASD/ID that are further verified by many approaches, including many mouse and other models. These models have facilitated the identification of fundamental mechanisms underlying the pathogenesis of ASD/ID, and several studies have proposed converging molecular pathways in ASD/ID. However, linking the mechanisms of the pathogenic genes and their molecular characteristics that lead to ID/ASD has progressed slowly, hampering the development of potential therapeutic strategies. This review discusses the possibility of recognising the common molecular causes for most ASD/ID based on studies from the available models that may enable a better therapeutic strategy to treat ID/ASD. We also reviewed the potential biomarkers to detect ASD/ID at early stages that may aid in diagnosis and initiating medical treatment, the concerns with drug failure in clinical trials, and developing therapeutic strategies that can be applied beyond a particular mutation associated with ASD/ID.
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Affiliation(s)
- Sushmitha S Purushotham
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India
| | - Neeharika M N Reddy
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India
| | - Michelle Ninochka D'Souza
- Centre for Brain Research, Indian Institute of Science Campus, CV Raman Avenue, Bangalore, 560 012, India.,The University of Trans-Disciplinary Health Sciences and Technology (TDU), Bangalore, 560064, India
| | - Nilpawan Roy Choudhury
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India
| | - Anusa Ganguly
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India
| | - Niharika Gopalakrishna
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India
| | - Ravi Muddashetty
- Centre for Brain Research, Indian Institute of Science Campus, CV Raman Avenue, Bangalore, 560 012, India.,The University of Trans-Disciplinary Health Sciences and Technology (TDU), Bangalore, 560064, India
| | - James P Clement
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, 560064, India.
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10
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Polese D, Riccio ML, Fagioli M, Mazzetta A, Fagioli F, Parisi P, Fagioli M. The Newborn's Reaction to Light as the Determinant of the Brain's Activation at Human Birth. Front Integr Neurosci 2022; 16:933426. [PMID: 36118115 PMCID: PMC9478760 DOI: 10.3389/fnint.2022.933426] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
Developmental neuroscience research has not yet fully unveiled the dynamics involved in human birth. The trigger of the first breath, often assumed to be the marker of human life, has not been characterized nor has the process entailing brain modification and activation at birth been clarified yet. To date, few researchers only have investigated the impact of the extrauterine environment, with its strong stimuli, on birth. This ‘hypothesis and theory' article assumes the role of a specific stimulus activating the central nervous system (CNS) at human birth. This stimulus must have specific features though, such as novelty, efficacy, ubiquity, and immediacy. We propose light as a robust candidate for the CNS activation via the retina. Available data on fetal and neonatal neurodevelopment, in particular with reference to retinal light-responsive pathways, will be examined together with the GABA functional switch, and the subplate disappearance, which, at an experimental level, differentiate the neonatal brain from the fetal brain. In this study, we assume how a very rapid activation of retinal photoreceptors at birth initiates a sudden brain shift from the prenatal pattern of functions to the neonatal setup. Our assumption implies the presence of a photoreceptor capable of capturing and transducing light/photon stimulus, transforming it into an effective signal for the activation of new brain functions at birth. Opsin photoreception or, more specifically, melanopsin-dependent photoreception, which is provided by intrinsically photosensitive retinal ganglion cells (ipRGCs), is considered as a valid candidate. Although what is assumed herein cannot be verified in humans based on knowledge available so far, proposing an important and novel function can trigger a broad range of diversified research in different domains, from neurophysiology to neurology and psychiatry.
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Affiliation(s)
- Daniela Polese
- PhD Program on Sensorineural Plasticity, Department of Neuroscience, Mental Health and Sensory Organs NESMOS, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
- *Correspondence: Daniela Polese
| | | | - Marcella Fagioli
- Department of Mental Health, National Health System ASL Rome 1, Rome, Italy
| | - Alessandro Mazzetta
- PhD Program on Neuroscience, Department of Systems Medicine, Tor Vergata University, Rome, Italy
| | - Francesca Fagioli
- Department of Mental Health, National Health System ASL Rome 1, Rome, Italy
| | - Pasquale Parisi
- Chair of Pediatrics, Department of Neuroscience, Mental Health and Sensory Organs NESMOS, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
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11
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Delpire E, Ben-Ari Y. A Wholistic View of How Bumetanide Attenuates Autism Spectrum Disorders. Cells 2022; 11:cells11152419. [PMID: 35954263 PMCID: PMC9367773 DOI: 10.3390/cells11152419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/22/2022] [Accepted: 08/03/2022] [Indexed: 01/27/2023] Open
Abstract
The specific NKCC1 cotransporter antagonist, bumetanide, attenuates the severity of Autism Spectrum Disorders (ASD), and many neurodevelopmental or neurodegenerative disorders in animal models and clinical trials. However, the pervasive expression of NKCC1 in many cell types throughout the body is thought to challenge the therapeutic efficacy of bumetanide. However, many peripheral functions, including intestinal, metabolic, or vascular, etc., are perturbed in brain disorders contributing to the neurological sequels. Alterations of these functions also increase the incidence of the disorder suggesting complex bidirectional links with the clinical manifestations. We suggest that a more holistic view of ASD and other disorders is warranted to account for the multiple sites impacted by the original intra-uterine insult. From this perspective, large-spectrum active repositioned drugs that act centrally and peripherally might constitute a useful approach to treating these disorders.
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Affiliation(s)
- Eric Delpire
- Departments of Anesthesiology and Molecular Physiology & Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
- Correspondence:
| | - Yehezkel Ben-Ari
- NeuroChlore, Campus Scientifique de Luminy, 163 Route de Luminy, 13273 Marseilles, France
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12
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Bülow P, Segal M, Bassell GJ. Mechanisms Driving the Emergence of Neuronal Hyperexcitability in Fragile X Syndrome. Int J Mol Sci 2022; 23:ijms23116315. [PMID: 35682993 PMCID: PMC9181819 DOI: 10.3390/ijms23116315] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 02/04/2023] Open
Abstract
Hyperexcitability is a shared neurophysiological phenotype across various genetic neurodevelopmental disorders, including Fragile X syndrome (FXS). Several patient symptoms are associated with hyperexcitability, but a puzzling feature is that their onset is often delayed until their second and third year of life. It remains unclear how and why hyperexcitability emerges in neurodevelopmental disorders. FXS is caused by the loss of FMRP, an RNA-binding protein which has many critical roles including protein synthesis-dependent and independent regulation of ion channels and receptors, as well as global regulation of protein synthesis. Here, we discussed recent literature uncovering novel mechanisms that may drive the progressive onset of hyperexcitability in the FXS brain. We discussed in detail how recent publications have highlighted defects in homeostatic plasticity, providing new insight on the FXS brain and suggest pharmacotherapeutic strategies in FXS and other neurodevelopmental disorders.
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Affiliation(s)
- Pernille Bülow
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence: (P.B.); (G.J.B.)
| | - Menahem Segal
- Department of Brain Science, Weizmann Institute of Science, Rehovot 76100, Israel;
| | - Gary J. Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence: (P.B.); (G.J.B.)
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13
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Lv H, Gu X, Shan X, Zhu T, Ma B, Zhang HT, Bambini-Junior V, Zhang T, Li WG, Gao X, Li F. Nanoformulated Bumetanide Ameliorates Social Deficiency in BTBR Mice Model of Autism Spectrum Disorder. Front Immunol 2022; 13:870577. [PMID: 35693812 PMCID: PMC9179025 DOI: 10.3389/fimmu.2022.870577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/21/2022] [Indexed: 11/13/2022] Open
Abstract
Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder with few medication options. Bumetanide, an FDA-approved diuretic, has been proposed as a viable candidate to treat core symptoms of ASD, however, neither the brain region related to its effect nor the cell-specific mechanism(s) is clear. The availability of nanoparticles provides a viable way to identify pharmacological mechanisms for use in ASD. Here, we found that treatment with bumetanide, in a systemic and medial prefrontal cortex (mPFC) region-specific way, attenuated social deficits in BTBR mice. Furthermore, using poly (ethylene glycol)-poly(l-lactide) (PEG-PLA) nanoparticles [NP(bumetanide)], we showed that the administration of NP(bumetanide) in a mPFC region-specific way also alleviated the social deficits of BTBR mice. Mechanistically, the behavioral effect of NP(bumetanide) was dependent on selective microglia-specific targeting in the mPFC. Pharmacological depletion of microglia significantly reduced the effect of nanoencapsulation and depletion of microglia alone did not improve the social deficits in BTBR mice. These findings suggest the potential therapeutic capabilities of nanotechnology for ASD, as well as the relevant link between bumetanide and immune cells.
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Affiliation(s)
- Hui Lv
- Department of Developmental and Behavioral Pediatric & Child Primary Care, Brain and Behavioural Research Unit of Shanghai Institute for Pediatric Research and Ministry of Education-Shanghai Key Laboratory for Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiao Gu
- Department of Pharmacology and Chemical Biology, Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xingyue Shan
- Shanghai Key Laboratory of Brain Functional Genomics (Ministry of Education), School of Life Sciences, East China Normal University, Shanghai, China
| | - Tailin Zhu
- Department of Developmental and Behavioral Pediatric & Child Primary Care, Brain and Behavioural Research Unit of Shanghai Institute for Pediatric Research and Ministry of Education-Shanghai Key Laboratory for Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bingke Ma
- Shanghai Key Laboratory of Brain Functional Genomics (Ministry of Education), School of Life Sciences, East China Normal University, Shanghai, China
| | - Hao-Tian Zhang
- Brain and Behavioral Research Unit of Shanghai Institute for Pediatric Research and Ministry of Education (MOE)-Shanghai Key Laboratory for Children’s Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Victorio Bambini-Junior
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
| | - Tiantian Zhang
- Shanghai Key Laboratory of Brain Functional Genomics (Ministry of Education), School of Life Sciences, East China Normal University, Shanghai, China
| | - Wei-Guang Li
- Department of Rehabilitation Medicine, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Xiaoling Gao
- Department of Pharmacology and Chemical Biology, Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- *Correspondence: Fei Li, ; Xiaoling Gao,
| | - Fei Li
- Department of Developmental and Behavioral Pediatric & Child Primary Care, Brain and Behavioural Research Unit of Shanghai Institute for Pediatric Research and Ministry of Education-Shanghai Key Laboratory for Children's Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- *Correspondence: Fei Li, ; Xiaoling Gao,
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14
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NKCC1 Deficiency in Forming Hippocampal Circuits Triggers Neurodevelopmental Disorder: Role of BDNF-TrkB Signalling. Brain Sci 2022; 12:brainsci12040502. [PMID: 35448033 PMCID: PMC9030861 DOI: 10.3390/brainsci12040502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/06/2022] [Accepted: 04/12/2022] [Indexed: 12/10/2022] Open
Abstract
The time-sensitive GABA shift from excitatory to inhibitory is critical in early neural circuits development and depends upon developmentally regulated expression of cation-chloride cotransporters NKCC1 and KCC2. NKCC1, encoded by the SLC12A2 gene, regulates neuronal Cl− homeostasis by chloride import working opposite KCC2. The high NKCC1/KCC2 expression ratio decreases in early neural development contributing to GABA shift. Human SLC12A2 loss-of-function mutations were recently associated with a multisystem disorder affecting neural development. However, the multisystem phenotype of rodent Nkcc1 knockout models makes neurodevelopment challenging to study. Brain-Derived Neurotrophic Factor (BDNF)-NTRK2/TrkB signalling controls KCC2 expression during neural development, but its impact on NKCC1 is still controversial. Here, we discuss recent evidence supporting BDNF-TrkB signalling controlling Nkcc1 expression and the GABA shift during hippocampal circuit formation. Namely, specific deletion of Ntrk2/Trkb from immature mouse hippocampal dentate granule cells (DGCs) affects their integration and maturation in the hippocampal circuitry and reduces Nkcc1 expression in their target region, the CA3 principal cells, leading to premature GABA shift, ultimately influencing the establishment of functional hippocampal circuitry and animal behaviour in adulthood. Thus, immature DGCs emerge as a potential therapeutic target as GABAergic transmission is vital for specific neural progenitors generating dentate neurogenesis in early development and the mature brain.
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15
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Montanari M, Martella G, Bonsi P, Meringolo M. Autism Spectrum Disorder: Focus on Glutamatergic Neurotransmission. Int J Mol Sci 2022; 23:ijms23073861. [PMID: 35409220 PMCID: PMC8998955 DOI: 10.3390/ijms23073861] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 12/16/2022] Open
Abstract
Disturbances in the glutamatergic system have been increasingly documented in several neuropsychiatric disorders, including autism spectrum disorder (ASD). Glutamate-centered theories of ASD are based on evidence from patient samples and postmortem studies, as well as from studies documenting abnormalities in glutamatergic gene expression and metabolic pathways, including changes in the gut microbiota glutamate metabolism in patients with ASD. In addition, preclinical studies on animal models have demonstrated glutamatergic neurotransmission deficits and altered expression of glutamate synaptic proteins. At present, there are no approved glutamatergic drugs for ASD, but several ongoing clinical trials are currently focusing on evaluating in autistic patients glutamatergic pharmaceuticals already approved for other conditions. In this review, we provide an overview of the literature concerning the role of glutamatergic neurotransmission in the pathophysiology of ASD and as a potential target for novel treatments.
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Affiliation(s)
- Martina Montanari
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Department of Systems Neuroscience, University Tor Vergata, 00133 Rome, Italy
| | - Giuseppina Martella
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
| | - Paola Bonsi
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Correspondence: (P.B.); (M.M.)
| | - Maria Meringolo
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, 00179 Rome, Italy; (M.M.); (G.M.)
- Correspondence: (P.B.); (M.M.)
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16
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Li W. Excitation and Inhibition Imbalance in Rett Syndrome. Front Neurosci 2022; 16:825063. [PMID: 35250460 PMCID: PMC8894599 DOI: 10.3389/fnins.2022.825063] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/31/2022] [Indexed: 12/12/2022] Open
Abstract
A loss of the excitation/inhibition (E/I) balance in the neural circuit has emerged as a common neuropathological feature in many neurodevelopmental disorders. Rett syndrome (RTT), a prevalent neurodevelopmental disorder that affects 1:10,000-15,000 women globally, is caused by loss-of-function mutations in the Methyl-CpG-binding Protein-2 (Mecp2) gene. E/I imbalance is recognized as the leading cellular and synaptic hallmark that is fundamental to diverse RTT neurological symptoms, including stereotypic hand movements, impaired motor coordination, breathing irregularities, seizures, and learning/memory dysfunctions. E/I balance in RTT is not homogeneously altered but demonstrates brain region and cell type specificity instead. In this review, I elaborate on the current understanding of the loss of E/I balance in a range of brain areas at molecular and cellular levels. I further describe how the underlying cellular mechanisms contribute to the disturbance of the proper E/I ratio. Last, I discuss current pharmacologic innervations for RTT and their role in modifying the E/I balance.
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Affiliation(s)
- Wei Li
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, United States
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17
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Ben-Ari Y, Cherubini E. The GABA Polarity Shift and Bumetanide Treatment: Making Sense Requires Unbiased and Undogmatic Analysis. Cells 2022; 11:396. [PMID: 35159205 PMCID: PMC8834580 DOI: 10.3390/cells11030396] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/05/2022] [Accepted: 01/13/2022] [Indexed: 12/17/2022] Open
Abstract
GABA depolarizes and often excites immature neurons in all animal species and brain structures investigated due to a developmentally regulated reduction in intracellular chloride concentration ([Cl-]i) levels. The control of [Cl-]i levels is mediated by the chloride cotransporters NKCC1 and KCC2, the former usually importing chloride and the latter exporting it. The GABA polarity shift has been extensively validated in several experimental conditions using often the NKCC1 chloride importer antagonist bumetanide. In spite of an intrinsic heterogeneity, this shift is abolished in many experimental conditions associated with developmental disorders including autism, Rett syndrome, fragile X syndrome, or maternal immune activation. Using bumetanide, an EMA- and FDA-approved agent, many clinical trials have shown promising results with the expected side effects. Kaila et al. have repeatedly challenged these experimental and clinical observations. Here, we reply to the recent reviews by Kaila et al. stressing that the GABA polarity shift is solidly accepted by the scientific community as a major discovery to understand brain development and that bumetanide has shown promising effects in clinical trials.
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Affiliation(s)
- Yehezkel Ben-Ari
- Neurochlore, Batiment Beret Delaage, Campus Scientifique de Luminy, 13009 Marseille, France
| | - Enrico Cherubini
- European Brain Research Institute (EBRI)-Rita Levi-Montalcini, 00161 Roma, Italy;
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18
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Bach S, Shovlin S, Moriarty M, Bardoni B, Tropea D. Rett Syndrome and Fragile X Syndrome: Different Etiology With Common Molecular Dysfunctions. Front Cell Neurosci 2021; 15:764761. [PMID: 34867203 PMCID: PMC8640214 DOI: 10.3389/fncel.2021.764761] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/27/2021] [Indexed: 01/04/2023] Open
Abstract
Rett syndrome (RTT) and Fragile X syndrome (FXS) are two monogenetic neurodevelopmental disorders with complex clinical presentations. RTT is caused by mutations in the Methyl-CpG binding protein 2 gene (MECP2) altering the function of its protein product MeCP2. MeCP2 modulates gene expression by binding methylated CpG dinucleotides, and by interacting with transcription factors. FXS is caused by the silencing of the FMR1 gene encoding the Fragile X Mental Retardation Protein (FMRP), a RNA binding protein involved in multiple steps of RNA metabolism, and modulating the translation of thousands of proteins including a large set of synaptic proteins. Despite differences in genetic etiology, there are overlapping features in RTT and FXS, possibly due to interactions between MeCP2 and FMRP, and to the regulation of pathways resulting in dysregulation of common molecular signaling. Furthermore, basic physiological mechanisms are regulated by these proteins and might concur to the pathophysiology of both syndromes. Considering that RTT and FXS are disorders affecting brain development, and that most of the common targets of MeCP2 and FMRP are involved in brain activity, we discuss the mechanisms of synaptic function and plasticity altered in RTT and FXS, and we consider the similarities and the differences between these two disorders.
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Affiliation(s)
- Snow Bach
- School of Mathematical Sciences, Dublin City University, Dublin, Ireland.,Neuropsychiatric Genetics, Department of Psychiatry, School of Medicine, Trinity College Dublin, Trinity Translational Medicine Institute, St James's Hospital, Dublin, Ireland
| | - Stephen Shovlin
- Neuropsychiatric Genetics, Department of Psychiatry, School of Medicine, Trinity College Dublin, Trinity Translational Medicine Institute, St James's Hospital, Dublin, Ireland
| | | | - Barbara Bardoni
- Inserm, CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology, Université Côte d'Azur, Valbonne, France
| | - Daniela Tropea
- Neuropsychiatric Genetics, Department of Psychiatry, School of Medicine, Trinity College Dublin, Trinity Translational Medicine Institute, St James's Hospital, Dublin, Ireland.,Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,FutureNeuro, The SFI Research Centre for Chronic and Rare Neurological Diseases, Dublin, Ireland
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19
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Savardi A, Borgogno M, De Vivo M, Cancedda L. Pharmacological tools to target NKCC1 in brain disorders. Trends Pharmacol Sci 2021; 42:1009-1034. [PMID: 34620512 DOI: 10.1016/j.tips.2021.09.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/27/2021] [Accepted: 09/08/2021] [Indexed: 02/06/2023]
Abstract
The chloride importer NKCC1 and the chloride exporter KCC2 are key regulators of neuronal chloride concentration. A defective NKCC1/KCC2 expression ratio is associated with several brain disorders. Preclinical/clinical studies have shown that NKCC1 inhibition by the United States FDA-approved diuretic bumetanide is a potential therapeutic strategy in preclinical/clinical studies of multiple neurological conditions. However, bumetanide has poor brain penetration and causes unwanted diuresis by inhibiting NKCC2 in the kidney. To overcome these issues, a growing number of studies have reported more brain-penetrating and/or selective bumetanide prodrugs, analogs, and new molecular entities. Here, we review the evidence for NKCC1 pharmacological inhibition as an effective strategy to manage neurological disorders. We also discuss the advantages and limitations of bumetanide repurposing and the benefits and risks of new NKCC1 inhibitors as therapeutic agents for brain disorders.
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Affiliation(s)
- Annalisa Savardi
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genoa, Italy; Dulbecco Telethon Institute, 00185 Rome, Italy; Molecular Modeling and Drug Discovery Laboratory, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genoa, Italy
| | - Marco Borgogno
- Molecular Modeling and Drug Discovery Laboratory, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genoa, Italy
| | - Marco De Vivo
- Molecular Modeling and Drug Discovery Laboratory, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genoa, Italy.
| | - Laura Cancedda
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, via Morego, 30, 16163 Genoa, Italy; Dulbecco Telethon Institute, 00185 Rome, Italy.
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20
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The Alteration of Chloride Homeostasis/GABAergic Signaling in Brain Disorders: Could Oxidative Stress Play a Role? Antioxidants (Basel) 2021; 10:antiox10081316. [PMID: 34439564 PMCID: PMC8389245 DOI: 10.3390/antiox10081316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 12/22/2022] Open
Abstract
In neuronal precursors and immature neurons, the depolarizing (excitatory) effect of γ-Aminobutyric acid (GABA) signaling is associated with elevated [Cl−]i; as brain cells mature, a developmental switch occurs, leading to the decrease of [Cl−]i and to the hyperpolarizing (inhibitory) effect of GABAergic signaling. [Cl−]i is controlled by two chloride co-transporters: NKCC1, which causes Cl− to accumulate into the cells, and KCC2, which extrudes it. The ontogenetic upregulation of the latter determines the above-outlined switch; however, many other factors contribute to the correct [Cl−]i in mature neurons. The dysregulation of chloride homeostasis is involved in seizure generation and has been associated with schizophrenia, Down’s Syndrome, Autism Spectrum Disorder, and other neurodevelopmental disorders. Recently, much effort has been put into developing new drugs intended to inhibit NKCC1 activity, while no attention has been paid to the origin of [Cl−]i dysregulation. Our study examines the pathophysiology of Cl− homeostasis and focuses on the impact of oxidative stress (OS) and inflammation on the activity of Cl− co-transporters, highlighting the relevance of OS in numerous brain abnormalities and diseases. This hypothesis supports the importance of primary prevention during pregnancy. It also integrates the therapeutic framework addressed to restore normal GABAergic signaling by counteracting the alteration in chloride homeostasis in central nervous system (CNS) cells, aiming at limiting the use of drugs that potentially pose a health risk.
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21
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Carstens KE, Lustberg DJ, Shaughnessy EK, McCann KE, Alexander GM, Dudek SM. Perineuronal net degradation rescues CA2 plasticity in a mouse model of Rett syndrome. J Clin Invest 2021; 131:e137221. [PMID: 34228646 DOI: 10.1172/jci137221] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/25/2021] [Indexed: 12/14/2022] Open
Abstract
Perineuronal nets (PNNs), a specialized form of extracellular matrix, are abnormal in the brains of people with Rett syndrome (RTT). We previously reported that PNNs function to restrict synaptic plasticity in hippocampal area CA2, which is unusually resistant to long-term potentiation (LTP) and has been linked to social learning in mice. Here we report that PNNs appear elevated in area CA2 of the hippocampus of an individual with RTT and that PNNs develop precociously and remain elevated in area CA2 of a mouse model of RTT (Mecp2-null). Further, we provide evidence that LTP could be induced at CA2 synapses prior to PNN maturation (postnatal day 8-11) in wild-type mice and that this window of plasticity was prematurely restricted at CA2 synapses in Mecp2-null mice. Degrading PNNs in Mecp2-null hippocampus was sufficient to rescue the premature disruption of CA2 plasticity. We identified several molecular targets that were altered in the developing Mecp2-null hippocampus that may explain aberrant PNNs and CA2 plasticity, and we discovered that CA2 PNNs are negatively regulated by neuronal activity. Collectively, our findings demonstrate that CA2 PNN development is regulated by Mecp2 and identify a window of hippocampal plasticity that is disrupted in a mouse model of RTT.
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22
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Parrini M, Naskar S, Alberti M, Colombi I, Morelli G, Rocchi A, Nanni M, Piccardi F, Charles S, Ronzitti G, Mingozzi F, Contestabile A, Cancedda L. Restoring neuronal chloride homeostasis with anti-NKCC1 gene therapy rescues cognitive deficits in a mouse model of Down syndrome. Mol Ther 2021; 29:3072-3092. [PMID: 34058387 PMCID: PMC8531145 DOI: 10.1016/j.ymthe.2021.05.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/27/2021] [Accepted: 05/18/2021] [Indexed: 01/24/2023] Open
Abstract
A common feature of diverse brain disorders is the alteration of GABA-mediated inhibition because of aberrant, intracellular chloride homeostasis induced by changes in the expression and/or function of chloride transporters. Notably, pharmacological inhibition of the chloride importer NKCC1 is able to rescue brain-related core deficits in animal models of these pathologies and in some human clinical studies. Here, we show that reducing NKCC1 expression by RNA interference in the Ts65Dn mouse model of Down syndrome (DS) restores intracellular chloride concentration, efficacy of gamma-aminobutyric acid (GABA)-mediated inhibition, and neuronal network dynamics in vitro and ex vivo. Importantly, adeno-associated virus (AAV)-mediated, neuron-specific NKCC1 knockdown in vivo rescues cognitive deficits in diverse behavioral tasks in Ts65Dn animals. Our results highlight a mechanistic link between NKCC1 expression and behavioral abnormalities in DS mice and establish a molecular target for new therapeutic approaches, including gene therapy, to treat brain disorders characterized by neuronal chloride imbalance.
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Affiliation(s)
- Martina Parrini
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Shovan Naskar
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Micol Alberti
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Ilaria Colombi
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Giovanni Morelli
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Anna Rocchi
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132 Genoa, Italy; IRCSS Ospedale Policlinico San Martino, 16132 Genoa, Italy
| | - Marina Nanni
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Federica Piccardi
- Animal Facility, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Severine Charles
- Genethon, 91000 Evry, France; Paris-Saclay University, University Evry, Inserm, Integrare research unit UMR_S951, 91000 Evry, France
| | - Giuseppe Ronzitti
- Genethon, 91000 Evry, France; Paris-Saclay University, University Evry, Inserm, Integrare research unit UMR_S951, 91000 Evry, France
| | - Federico Mingozzi
- Genethon, 91000 Evry, France; Paris-Saclay University, University Evry, Inserm, Integrare research unit UMR_S951, 91000 Evry, France
| | - Andrea Contestabile
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy.
| | - Laura Cancedda
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, 16163 Genoa, Italy; Dulbecco Telethon Institute, 00185 Rome, Italy.
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23
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Sahin GS, Luis Rodriguez-Llamas J, Dillon C, Medina I, Appleyard SM, Gaiarsa JL, Wayman GA. Leptin increases GABAergic synaptogenesis through the Rho guanine exchange factor β-PIX in developing hippocampal neurons. Sci Signal 2021; 14:14/683/eabe4111. [PMID: 34006608 DOI: 10.1126/scisignal.abe4111] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Developing hippocampal neurons undergo rapid synaptogenesis in response to neurotrophic signals to form and refine circuit connections. The adipokine leptin is a satiety factor with neurotrophic actions, which potentiates both glutamatergic and GABAergic synaptogenesis in the hippocampus during neonatal development. Brief exposure to leptin enhances GABAA receptor-dependent synaptic currents in hippocampal neurons. Here, using molecular and electrophysiological techniques, we found that leptin increased the surface localization of GABAA receptors and the number of functional GABAergic synapses in hippocampal cultures from male and female rat pups. Leptin increased the interaction between GABAA receptors and the Rho guanine exchange factor β-PIX (a scaffolding protein at GABAergic postsynaptic sites) in a manner dependent on the kinase CaMKK. We also found that the leptin receptor and β-PIX formed a complex, the amount of which transiently increased upon leptin receptor activation. Furthermore, Tyr985 in the leptin receptor and the SH3 domain of β-PIX are crucial for this interaction, which was required for the developmental increase in GABAergic synaptogenesis. Our results suggest a mechanism by which leptin promotes GABAergic synaptogenesis in hippocampal neurons and reveal further complexity in leptin receptor signaling and its interactome.
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Affiliation(s)
- Gulcan Semra Sahin
- Department of Integrated Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA
| | - Jose Luis Rodriguez-Llamas
- Department of Integrated Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA
| | - Crystal Dillon
- Department of Integrated Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA
| | - Igor Medina
- Aix-Marseille University UMR 1249, INSERM (Institut National de la Santé et de la Recherche Médicale) Unité 1249, INMED (Institut de Neurobiologie de la Méditerranée), Marseille, France
| | - Suzanne M Appleyard
- Department of Integrated Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA
| | - Jean-Luc Gaiarsa
- Aix-Marseille University UMR 1249, INSERM (Institut National de la Santé et de la Recherche Médicale) Unité 1249, INMED (Institut de Neurobiologie de la Méditerranée), Marseille, France
| | - Gary A Wayman
- Department of Integrated Physiology and Neuroscience, Washington State University, Pullman, WA 99164 USA.
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24
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Reviewing Evidence for the Relationship of EEG Abnormalities and RTT Phenotype Paralleled by Insights from Animal Studies. Int J Mol Sci 2021; 22:ijms22105308. [PMID: 34069993 PMCID: PMC8157853 DOI: 10.3390/ijms22105308] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/09/2021] [Accepted: 05/12/2021] [Indexed: 12/29/2022] Open
Abstract
Rett syndrome (RTT) is a rare neurodevelopmental disorder that is usually caused by mutations of the MECP2 gene. Patients with RTT suffer from severe deficits in motor, perceptual and cognitive domains. Electroencephalogram (EEG) has provided useful information to clinicians and scientists, from the very first descriptions of RTT, and yet no reliable neurophysiological biomarkers related to the pathophysiology of the disorder or symptom severity have been identified to date. To identify consistently observed and potentially informative EEG characteristics of RTT pathophysiology, and ascertain areas most worthy of further systematic investigation, here we review the literature for EEG abnormalities reported in patients with RTT and in its disease models. While pointing to some promising potential EEG biomarkers of RTT, our review identify areas of need to realize the potential of EEG including (1) quantitative investigation of promising clinical-EEG observations in RTT, e.g., shift of mu rhythm frequency and EEG during sleep; (2) closer alignment of approaches between patients with RTT and its animal models to strengthen the translational significance of the work (e.g., EEG measurements and behavioral states); (3) establishment of large-scale consortium research, to provide adequate Ns to investigate age and genotype effects.
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25
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Scaramuzza L, De Rocco G, Desiato G, Cobolli Gigli C, Chiacchiaretta M, Mirabella F, Pozzi D, De Simone M, Conforti P, Pagani M, Benfenati F, Cesca F, Bedogni F, Landsberger N. The enhancement of activity rescues the establishment of Mecp2 null neuronal phenotypes. EMBO Mol Med 2021; 13:e12433. [PMID: 33665914 PMCID: PMC8033520 DOI: 10.15252/emmm.202012433] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 01/24/2021] [Accepted: 01/27/2021] [Indexed: 01/29/2023] Open
Abstract
MECP2 mutations cause Rett syndrome (RTT), a severe and progressive neurodevelopmental disorder mainly affecting females. Although RTT patients exhibit delayed onset of symptoms, several evidences demonstrate that MeCP2 deficiency alters early development of the brain. Indeed, during early maturation, Mecp2 null cortical neurons display widespread transcriptional changes, reduced activity, and defective morphology. It has been proposed that during brain development these elements are linked in a feed-forward cycle where neuronal activity drives transcriptional and morphological changes that further increase network maturity. We hypothesized that the enhancement of neuronal activity during early maturation might prevent the onset of RTT-typical molecular and cellular phenotypes. Accordingly, we show that the enhancement of excitability, obtained by adding to neuronal cultures Ampakine CX546, rescues transcription of several genes, neuronal morphology, and responsiveness to stimuli. Greater effects are achieved in response to earlier treatments. In vivo, short and early administration of CX546 to Mecp2 null mice prolongs lifespan, delays the disease progression, and rescues motor abilities and spatial memory, thus confirming the value for RTT of an early restoration of neuronal activity.
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Affiliation(s)
- Linda Scaramuzza
- Division of NeuroscienceIRCCS San Raffaele Scientific InstituteMilanItaly
- Present address:
Department of Bioscience, University of Milan, Milan, Italy; Istituto Nazionale Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
| | - Giuseppina De Rocco
- Division of NeuroscienceIRCCS San Raffaele Scientific InstituteMilanItaly
- Department of Medical Biotechnology and Translational MedicineUniversity of MilanMilanItaly
| | - Genni Desiato
- IRCCS Humanitas Research HospitalMilanItaly
- CNR Institute of NeuroscienceMilanItaly
| | - Clementina Cobolli Gigli
- Division of NeuroscienceIRCCS San Raffaele Scientific InstituteMilanItaly
- Present address:
Francis Crick InstituteLondonUK
| | - Martina Chiacchiaretta
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenovaItaly
- Present address:
Department of NeuroscienceTufts University School of MedicineBostonMAUSA
| | - Filippo Mirabella
- IRCCS Humanitas Research HospitalMilanItaly
- Department of Biomedical Sciences, Humanitas UniversityMilanItaly
| | - Davide Pozzi
- IRCCS Humanitas Research HospitalMilanItaly
- Department of Biomedical Sciences, Humanitas UniversityMilanItaly
| | - Marco De Simone
- Istituto Nazionale Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
- Present address:
Department of Radiation Oncology, Cedars-Sinai Medical CenterLos Angeles, CAUSA
| | - Paola Conforti
- Istituto Nazionale Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
- Department of BiosciencesUniversity of MilanMilanItaly
| | - Massimiliano Pagani
- Department of Medical Biotechnology and Translational MedicineUniversity of MilanMilanItaly
- Istituto Nazionale Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenovaItaly
- IRCCS Ospedale Policlinico San MartinoGenovaItaly
- Present address:
Francis Crick InstituteLondonUK
| | - Fabrizia Cesca
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenovaItaly
- Department of Life SciencesUniversity of TriesteTriesteItaly
- Present address:
Department of Radiation Oncology, Cedars-Sinai Medical CenterLos Angeles, CAUSA
| | - Francesco Bedogni
- Division of NeuroscienceIRCCS San Raffaele Scientific InstituteMilanItaly
- Present address:
Neuroscience and Mental Health Research Institute (NMHRI)Division of NeuroscienceSchool of BiosciencesCardiffUK
| | - Nicoletta Landsberger
- Division of NeuroscienceIRCCS San Raffaele Scientific InstituteMilanItaly
- Department of Medical Biotechnology and Translational MedicineUniversity of MilanMilanItaly
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26
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Caly H, Rabiei H, Coste-Mazeau P, Hantz S, Alain S, Eyraud JL, Chianea T, Caly C, Makowski D, Hadjikhani N, Lemonnier E, Ben-Ari Y. Machine learning analysis of pregnancy data enables early identification of a subpopulation of newborns with ASD. Sci Rep 2021; 11:6877. [PMID: 33767300 PMCID: PMC7994821 DOI: 10.1038/s41598-021-86320-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 03/10/2021] [Indexed: 01/31/2023] Open
Abstract
To identify newborns at risk of developing ASD and to detect ASD biomarkers early after birth, we compared retrospectively ultrasound and biological measurements of babies diagnosed later with ASD or neurotypical (NT) that are collected routinely during pregnancy and birth. We used a supervised machine learning algorithm with a cross-validation technique to classify NT and ASD babies and performed various statistical tests. With a minimization of the false positive rate, 96% of NT and 41% of ASD babies were identified with a positive predictive value of 77%. We identified the following biomarkers related to ASD: sex, maternal familial history of auto-immune diseases, maternal immunization to CMV, IgG CMV level, timing of fetal rotation on head, femur length in the 3rd trimester, white blood cell count in the 3rd trimester, fetal heart rate during labor, newborn feeding and temperature difference between birth and one day after. Furthermore, statistical models revealed that a subpopulation of 38% of babies at risk of ASD had significantly larger fetal head circumference than age-matched NT ones, suggesting an in utero origin of the reported bigger brains of toddlers with ASD. Our results suggest that pregnancy follow-up measurements might provide an early prognosis of ASD enabling pre-symptomatic behavioral interventions to attenuate efficiently ASD developmental sequels.
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Affiliation(s)
- Hugues Caly
- Gynecology-Obstetrics Department, Mère-Enfant Hospital, University Hospital Center, Limoges, France
| | - Hamed Rabiei
- BABiomedical, Luminy Scientific Campus, Marseille, France
- Neurochlore, Luminy Scientific Campus, Marseille, France
| | - Perrine Coste-Mazeau
- Gynecology-Obstetrics Department, Mère-Enfant Hospital, University Hospital Center, Limoges, France
| | - Sebastien Hantz
- Bacteriology-Virology-Hygiene Department, University Hospital Center, Limoges, France
- French National Reference Center for Herpes Viruses, University Hospital Center, Limoges, France
| | - Sophie Alain
- Bacteriology-Virology-Hygiene Department, University Hospital Center, Limoges, France
- French National Reference Center for Herpes Viruses, University Hospital Center, Limoges, France
| | - Jean-Luc Eyraud
- Gynecology-Obstetrics Department, Mère-Enfant Hospital, University Hospital Center, Limoges, France
| | - Thierry Chianea
- Department of Biochemistry and Molecular Genetics, Dupuytren University Hospital, Limoges, France
| | - Catherine Caly
- Gynecology-Obstetrics Department, Mère-Enfant Hospital, University Hospital Center, Limoges, France
| | - David Makowski
- INRAE, UMR MIA 518, INRA AgroParisTech Université Paris-Saclay, Paris, France
| | - Nouchine Hadjikhani
- Martinos Center for Biomedical Imaging, Harvard Medical School, Boston, USA
- Gillberg Neuropsychiatry Center, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
| | - Eric Lemonnier
- Autism Expert Center and Autism Resource Center of Limousin, University Hospital Center, Limoges, France
| | - Yehezkel Ben-Ari
- BABiomedical, Luminy Scientific Campus, Marseille, France.
- Neurochlore, Luminy Scientific Campus, Marseille, France.
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27
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Delpire E. Advances in the development of novel compounds targeting cation-chloride cotransporter physiology. Am J Physiol Cell Physiol 2021; 320:C324-C340. [PMID: 33356948 PMCID: PMC8294628 DOI: 10.1152/ajpcell.00566.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 01/05/2023]
Abstract
For about half a century, the pharmacology of electroneutral cation-chloride cotransporters has been dominated by a few drugs that are widely used in clinical medicine. Because these diuretic drugs are so good at what they do, there has been little incentive in expanding their pharmacology. The increasing realization that cation-chloride cotransporters are involved in many other key physiological processes and the knowledge that different tissues express homologous proteins with matching transport functions have rekindled interest in drug discovery. This review summarizes the methods available to assess the function of these transporters and describe the multiple efforts that have made to identify new compounds. We describe multiple screens targeting KCC2 function and one screen designed to find compounds that discriminate between NKCC1 and NKCC2. Two of the KCC2 screens identified new inhibitors that are 3-4 orders of magnitude more potent than furosemide. Additional screens identified compounds that purportedly increase cell surface expression of the cotransporter, as well as several FDA-approved drugs that increase KCC2 transcription and expression. The technical details of each screen biased them toward specific processes in the life cycle of the transporter, making these efforts independent and complementary. In addition, each drug discovery effort contributes to our understanding of the biology of the cotransporters.
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Affiliation(s)
- Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee
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28
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Peerboom C, Wierenga CJ. The postnatal GABA shift: A developmental perspective. Neurosci Biobehav Rev 2021; 124:179-192. [PMID: 33549742 DOI: 10.1016/j.neubiorev.2021.01.024] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 01/13/2021] [Accepted: 01/28/2021] [Indexed: 12/13/2022]
Abstract
GABA is the major inhibitory neurotransmitter that counterbalances excitation in the mature brain. The inhibitory action of GABA relies on the inflow of chloride ions (Cl-), which hyperpolarizes the neuron. In early development, GABA signaling induces outward Cl- currents and is depolarizing. The postnatal shift from depolarizing to hyperpolarizing GABA is a pivotal event in brain development and its timing affects brain function throughout life. Altered timing of the postnatal GABA shift is associated with several neurodevelopmental disorders. Here, we argue that the postnatal shift from depolarizing to hyperpolarizing GABA represents the final shift in a sequence of GABA shifts, regulating proliferation, migration, differentiation, and finally plasticity of developing neurons. Each developmental GABA shift ensures that the instructive role of GABA matches the circumstances of the developing network. Sensory input may be a crucial factor in determining proper timing of the postnatal GABA shift. A developmental perspective is necessary to interpret the full consequences of a mismatch between connectivity, activity and GABA signaling during brain development.
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Affiliation(s)
- Carlijn Peerboom
- Cell Biology, Neurobiology and Biophysics, Biology Department, Faculty of Science, Utrecht University, 3584 CH, Utrecht, the Netherlands
| | - Corette J Wierenga
- Cell Biology, Neurobiology and Biophysics, Biology Department, Faculty of Science, Utrecht University, 3584 CH, Utrecht, the Netherlands.
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29
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Affiliation(s)
- Odile A van den Heuvel
- Departments of Psychiatry and Anatomy and Neuroscience, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, the Netherlands
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30
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Belaïdouni Y, Diabira D, Zhang J, Graziano JC, Bader F, Montheil A, Menuet C, Wayman GA, Gaiarsa JL. The Chloride Homeostasis of CA3 Hippocampal Neurons Is Not Altered in Fully Symptomatic Mepc2-null Mice. Front Cell Neurosci 2021; 15:724976. [PMID: 34602980 PMCID: PMC8484709 DOI: 10.3389/fncel.2021.724976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/27/2021] [Indexed: 02/05/2023] Open
Abstract
Rett syndrome (RTT) is an X-linked neurodevelopmental disorder caused mainly by mutations in the MECP2 gene. Mouse models of RTT show reduced expression of the cation-chloride cotransporter KCC2 and altered chloride homeostasis at presymptomatic stages. However, whether these alterations persist to late symptomatic stages has not been studied. Here we assess KCC2 and NKCC1 expressions and chloride homeostasis in the hippocampus of early [postnatal (P) day 30-35] and late (P50-60) symptomatic male Mecp2-null (Mecp2 -/y) mice. We found (i) no difference in the relative amount, but an over-phosphorylation, of KCC2 and NKCC1 between wild-type (WT) and Mecp2 -/y hippocampi and (ii) no difference in the inhibitory strength, nor reversal potential, of GABA A -receptor-mediated responses in Mecp2 -/y CA3 pyramidal neurons compared to WT at any stages studied. Altogether, these data indicate the presence of a functional chloride extrusion mechanism in Mecp2 -/y CA3 pyramidal neurons at symptomatic stages.
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Affiliation(s)
- Yasmine Belaïdouni
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
| | - Diabe Diabira
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
| | - Jinwei Zhang
- Institute of Biomedical and Clinical Sciences, College of Medicine and Health, University of Exeter, Hatherly Laboratories, Exeter, United Kingdom
| | - Jean-Charles Graziano
- Aix-Marseille University 105, Institut Paoli Calmettes, U1068, Institut National de la Santé et de la Recherche Médicale U7258, Centre National de Recherche Scientifique, Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Francesca Bader
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
| | - Aurelie Montheil
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
| | - Clément Menuet
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
| | - Gary A. Wayman
- Program in Neuroscience, Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA, United States
| | - Jean-Luc Gaiarsa
- Aix-Marseille University UMR 1249, Institut de Neurobiologie de la Méditerranée, Institut National de la Santé et de la Recherche Médicale Unité 1249, Parc Scientifique de Luminy, Marseille, France
- *Correspondence: Jean-Luc Gaiarsa,
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31
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Xing H, Cui N, Johnson CM, Faisthalab Z, Jiang C. Dual synaptic inhibitions of brainstem neurons by GABA and glycine with impact on Rett syndrome. J Cell Physiol 2020; 236:3615-3628. [PMID: 33169374 DOI: 10.1002/jcp.30098] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/20/2020] [Accepted: 09/24/2020] [Indexed: 12/29/2022]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disease caused mostly by mutations in the MECP2 gene. People with RTT show breathing dysfunction attributable to the high rate of sudden death. Previous studies have shown that insufficient GABA synaptic inhibition contributes to the breathing abnormalities in mouse models of RTT, while it remains elusive how the glycine system is affected. We found that optogenetic stimulation of GAD-expressing neurons in mice produced GABAergic and glycinergic postsynaptic inhibitions of neurons in the hypoglossal nucleus (XII) and the dorsal motor nucleus of vagus (DMNV). By sequential applications of bicuculline and strychnine, such inhibition appeared approximately 44% GABAA ergic and 52% glycinergic in XII neurons, and approximately 49% GABAA ergic and 46% glycinergic in DMNV neurons. Miniature inhibitory postsynaptic potentials (mIPSCs) in these neurons were approximately 47% GABAA ergic and 49% glycinergic in XII neurons, and approximately 48% versus 50% in DMNV neurons, respectively. Consistent with the data, our single-cell polymerase chain reaction studies indicated that transcripts of GABAA receptor γ2 subunit (GABAA Rγ2) and glycine receptor β subunit (GlyRβ) were simultaneously expressed in these cells. In MeCP2R168X mice, proportions of GABAA ergic and glycinergic mIPSCs became approximately 28% versus 69% in XII neurons, and approximately 31% versus 66% in DMNV cells. In comparison with control mice, the GABAA ergic and glycinergic mIPSCs decreased significantly in the XII and DMNV neurons from the MeCP2R168X mice, so did the transcripts of GABAA Rγ2 and GlyRβ. These results suggest that XII and DMNV neurons adopt dual GABAA ergic and glycinergic synaptic inhibitions, and with Mecp2 disruption these neurons rely more on glycinergic synaptic inhibition.
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Affiliation(s)
- Hao Xing
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Ningren Cui
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | | | - Zaakir Faisthalab
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Chun Jiang
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
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32
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Environmental regulation of the chloride transporter KCC2: switching inflammation off to switch the GABA on? Transl Psychiatry 2020; 10:349. [PMID: 33060559 PMCID: PMC7562743 DOI: 10.1038/s41398-020-01027-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 09/08/2020] [Accepted: 09/14/2020] [Indexed: 12/15/2022] Open
Abstract
Chloride homeostasis, the main determinant factor for the dynamic tuning of GABAergic inhibition during development, has emerged as a key element altered in a wide variety of brain disorders. Accordingly, developmental disorders such as schizophrenia, Autism Spectrum Disorder, Down syndrome, epilepsy, and tuberous sclerosis complex (TSC) have been associated with alterations in the expression of genes codifying for either of the two cotransporters involved in the excitatory-to-inhibitory GABA switch, KCC2 and NKCC1. These alterations can result from environmental insults, including prenatal stress and maternal separation which share, as common molecular denominator, the elevation of pro-inflammatory cytokines. In this review we report and systemize recent research articles indicating that different perinatal environmental perturbations affect the expression of chloride transporters, delaying the developmental switch of GABA signaling, and that inflammatory cytokines, in particular interleukin 1β, may represent a key causal factor for this phenomenon. Based on literature data, we provide therefore a unifying conceptual framework, linking environmental hits with the excitatory-to-inhibitory GABA switch in the context of brain developmental disorders.
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33
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Ghatak S, Talantova M, McKercher SR, Lipton SA. Novel Therapeutic Approach for Excitatory/Inhibitory Imbalance in Neurodevelopmental and Neurodegenerative Diseases. Annu Rev Pharmacol Toxicol 2020; 61:701-721. [PMID: 32997602 DOI: 10.1146/annurev-pharmtox-032320-015420] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Excitatory/inhibitory (E/I) balance, defined as the balance between excitation and inhibition of synaptic activity in a neuronal network, accounts in part for the normal functioning of the brain, controlling, for example, normal spike rate. In many pathological conditions, this fine balance is perturbed, leading to excessive or diminished excitation relative to inhibition, termed E/I imbalance, reflected in network dysfunction. E/I imbalance has emerged as a contributor to neurological disorders that occur particularly at the extremes of life, including autism spectrum disorder and Alzheimer's disease, pointing to the vulnerability of neuronal networks at these critical life stages. Hence, it is important to develop approaches to rebalance neural networks. In this review, we describe emerging therapies that can normalize the E/I ratio or the underlying abnormality that contributes to the imbalance in electrical activity, thus improving neurological function in these maladies.
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Affiliation(s)
- Swagata Ghatak
- Department of Molecular Medicine and Neuroscience Translational Center, The Scripps Research Institute, La Jolla, California 92037, USA;
| | - Maria Talantova
- Department of Molecular Medicine and Neuroscience Translational Center, The Scripps Research Institute, La Jolla, California 92037, USA;
| | - Scott R McKercher
- Department of Molecular Medicine and Neuroscience Translational Center, The Scripps Research Institute, La Jolla, California 92037, USA;
| | - Stuart A Lipton
- Department of Molecular Medicine and Neuroscience Translational Center, The Scripps Research Institute, La Jolla, California 92037, USA; .,Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
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34
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Dehorter N, Del Pino I. Shifting Developmental Trajectories During Critical Periods of Brain Formation. Front Cell Neurosci 2020; 14:283. [PMID: 33132842 PMCID: PMC7513795 DOI: 10.3389/fncel.2020.00283] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/10/2020] [Indexed: 12/21/2022] Open
Abstract
Critical periods of brain development are epochs of heightened plasticity driven by environmental influence necessary for normal brain function. Recent studies are beginning to shed light on the possibility that timely interventions during critical periods hold potential to reorient abnormal developmental trajectories in animal models of neurological and neuropsychiatric disorders. In this review, we re-examine the criteria defining critical periods, highlighting the recently discovered mechanisms of developmental plasticity in health and disease. In addition, we touch upon technological improvements for modeling critical periods in human-derived neural networks in vitro. These scientific advances associated with the use of developmental manipulations in the immature brain of animal models are the basic preclinical systems that will allow the future translatability of timely interventions into clinical applications for neurodevelopmental disorders such as intellectual disability, autism spectrum disorders (ASD) and schizophrenia.
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Affiliation(s)
- Nathalie Dehorter
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Isabel Del Pino
- Principe Felipe Research Center (Centro de Investigación Principe Felipe, CIPF), Valencia, Spain
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35
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Nam KH, Yi SA, Jang HJ, Han JW, Lee J. In vitro modeling for inherited neurological diseases using induced pluripotent stem cells: from 2D to organoid. Arch Pharm Res 2020; 43:877-889. [PMID: 32761309 DOI: 10.1007/s12272-020-01260-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 07/29/2020] [Indexed: 12/20/2022]
Abstract
Stem cells are characterized by self-renewal and by their ability to differentiate into cells of various organs. With massive progress in 2D and 3D cell culture techniques, in vitro generation of various types of such organoids from patient-derived stem cells is now possible. As in vitro differentiation protocols are usually made to resemble human developmental processes, organogenesis of patient-derived stem cells can provide key information regarding a range of developmental diseases. Human stem cell-based in vitro modeling as opposed to using animal models can particularly benefit the evaluation of neurological diseases because of significant differences in structure and developmental processes between the human and the animal brain. This review focuses on stem cell-based in vitro modeling of neurodevelopmental disorders, more specifically, the fundamentals and technical advancements in monolayer neuron and brain organoid cultures. Furthermore, we discuss the drawbacks of the conventional culture method and explore the advanced, cutting edge 3D organoid models for several neurodevelopmental diseases, including genetic diseases such as Down syndrome, Rett syndrome, and Miller-Dieker syndrome, as well as brain malformations like macrocephaly and microcephaly. Finally, we discuss the limitations of the current organoid techniques and some potential solutions that pave the way for accurate modeling of neurological disorders in a dish.
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Affiliation(s)
- Ki Hong Nam
- School of Pharmacy, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Sang Ah Yi
- School of Pharmacy, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyun Ji Jang
- School of Pharmacy, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jeung-Whan Han
- School of Pharmacy, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Jaecheol Lee
- School of Pharmacy, Sungkyunkwan University, Suwon, 16419, Republic of Korea. .,Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, Suwon, 16419, Republic of Korea. .,Imnewrun Biosciences Inc., Suwon, 16419, Republic of Korea.
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36
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Otsu Y, Donneger F, Schwartz EJ, Poncer JC. Cation-chloride cotransporters and the polarity of GABA signalling in mouse hippocampal parvalbumin interneurons. J Physiol 2020; 598:1865-1880. [PMID: 32012273 DOI: 10.1113/jp279221] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 01/13/2020] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Cation-chloride cotransporters (CCCs) play a critical role in controlling the efficacy and polarity of GABAA receptor (GABAA R)-mediated transmission in the brain, yet their expression and function in GABAergic interneurons has been overlooked. We compared the polarity of GABA signalling and the function of CCCs in mouse hippocampal pyramidal neurons and parvalbumin-expressing interneurons. Under resting conditions, GABAA R activation was mostly depolarizing and yet inhibitory in both cell types. KCC2 blockade further depolarized the reversal potential of GABAA R-mediated currents often above action potential threshold. However, during repetitive GABAA R activation, the postsynaptic response declined independently of the ion flux direction or KCC2 function, suggesting intracellular chloride build-up is not responsible for this form of plasticity. Our data demonstrate similar mechanisms of chloride regulation in mouse hippocampal pyramidal neurons and parvalbumin interneurons. ABSTRACT Transmembrane chloride gradients govern the efficacy and polarity of GABA signalling in neurons and are usually maintained by the activity of cation-chloride cotransporters, such as KCC2 and NKCC1. Whereas their role is well established in cortical principal neurons, it remains poorly documented in GABAergic interneurons. We used complementary electrophysiological approaches to compare the effects of GABAA receptor (GABAA R) activation in adult mouse hippocampal parvalbumin interneurons (PV-INs) and pyramidal cells (PCs). Loose cell-attached, tight-seal and gramicidin-perforated patch recordings all show GABAA R-mediated transmission is slightly depolarizing and yet inhibitory in both PV-INs and PCs. Focal GABA uncaging in whole-cell recordings reveal that KCC2 and NKCC1 are functional in both PV-INs and PCs but differentially contribute to transmembrane chloride gradients in their soma and dendrites. Blocking KCC2 function depolarizes the reversal potential of GABAA R-mediated currents in PV-INs and PCs, often beyond firing threshold, showing KCC2 is essential to maintain the inhibitory effect of GABAA Rs. Finally, we show that repetitive 10 Hz activation of GABAA Rs in both PV-INs and PCs leads to a progressive decline of the postsynaptic response independently of the ion flux direction or KCC2 function. This suggests intraneuronal chloride build-up may not predominantly contribute to activity-dependent plasticity of GABAergic synapses in this frequency range. Altogether our data demonstrate similar mechanisms of chloride regulation in mouse hippocampal PV-INs and PCs and suggest KCC2 downregulation in the pathology may affect the valence of GABA signalling in both cell types.
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Affiliation(s)
- Yo Otsu
- Inserm UMR-S 1270, 75005, Paris, France.,Sorbonne Université, F75005, Paris, France.,Institut du Fer à Moulin, F75005, Paris, France
| | - Florian Donneger
- Inserm UMR-S 1270, 75005, Paris, France.,Sorbonne Université, F75005, Paris, France.,Institut du Fer à Moulin, F75005, Paris, France
| | - Eric J Schwartz
- Inserm UMR-S 1270, 75005, Paris, France.,Sorbonne Université, F75005, Paris, France.,Institut du Fer à Moulin, F75005, Paris, France
| | - Jean Christophe Poncer
- Inserm UMR-S 1270, 75005, Paris, France.,Sorbonne Université, F75005, Paris, France.,Institut du Fer à Moulin, F75005, Paris, France
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37
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Symptom improvement in children with autism spectrum disorder following bumetanide administration is associated with decreased GABA/glutamate ratios. Transl Psychiatry 2020; 10:9. [PMID: 32066666 PMCID: PMC7026137 DOI: 10.1038/s41398-020-0692-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 11/23/2019] [Accepted: 12/08/2019] [Indexed: 12/11/2022] Open
Abstract
Bumetanide has been reported to alter synaptic excitation-inhibition (E-I) balance by potentiating the action of γ-aminobutyric acid (GABA), thereby attenuating the severity of autism spectrum disorder (ASD) in animal models. However, clinical evidence of its efficacy in young patients with ASD is limited. This was investigated in the present clinical trial of 83 patients, randomised to the bumetanide group (bumetanide treatment, 0.5 mg twice daily) or the control group (no bumetanide treatment). Primary [Children Autism Rating Scale (CARS)], secondary [Clinical Global Impressions (CGI)], and exploratory [inhibitory (γ-aminobutyric acid, GABA) and excitatory (glutamate, Glx) neurotransmitter concentrations measured in the insular cortex (IC) and visual cortex (VC) by magnetic resonance spectroscopy (MRS)] outcome measures were evaluated at baseline and at the 3-month follow-up. Side effects were monitored throughout the treatment course. Compared with the control group, the bumetanide group showed significant reduction in symptom severity, as indicated by both total CARS score and number of items assigned a score ≥ 3. The improvement in clinical symptoms was confirmed by CGI. GABA/Glx ratio in both the IC and VC decreased more rapidly over the 3-month period in the bumetanide group than that in the control group. This decrease in the IC was associated with the symptom improvement in the bumetanide group. Our study confirmed the clinical efficacy of bumetanide on alleviating the core symptoms of ASD in young children and it is the first demonstration that the improvement is associated with reduction in GABA/Glx ratios. This study suggests that the GABA/Glx ratio measured by MRS may provide a neuroimaging biomarker for assessing treatment efficacy for bumetanide.
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38
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Comprehensive Analysis of GABA A-A1R Developmental Alterations in Rett Syndrome: Setting the Focus for Therapeutic Targets in the Time Frame of the Disease. Int J Mol Sci 2020; 21:ijms21020518. [PMID: 31947619 PMCID: PMC7014188 DOI: 10.3390/ijms21020518] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/03/2020] [Accepted: 01/10/2020] [Indexed: 02/08/2023] Open
Abstract
Rett syndrome, a serious neurodevelopmental disorder, has been associated with an altered expression of different synaptic-related proteins and aberrant glutamatergic and γ-aminobutyric acid (GABA)ergic neurotransmission. Despite its severity, it lacks a therapeutic option. Through this work we aimed to define the relationship between MeCP2 and GABAA.-A1 receptor expression, emphasizing the time dependence of such relationship. For this, we analyzed the expression of the ionotropic receptor subunit in different MeCP2 gene-dosage and developmental conditions, in cells lines, and in primary cultured neurons, as well as in different developmental stages of a Rett mouse model. Further, RNAseq and systems biology analysis was performed from post-mortem brain biopsies of Rett patients. We observed that the modulation of the MeCP2 expression in cellular models (both Neuro2a (N2A) cells and primary neuronal cultures) revealed a MeCP2 positive effect on the GABAA.-A1 receptor subunit expression, which did not occur in other proteins such as KCC2 (Potassium-chloride channel, member 5). In the Mecp2+/− mouse brain, both the KCC2 and GABA subunits expression were developmentally regulated, with a decreased expression during the pre-symptomatic stage, while the expression was variable in the adult symptomatic mice. Finally, the expression of the gamma-aminobutyric acid (GABA) receptor-related synaptic proteins from the postmortem brain biopsies of two Rett patients was evaluated, specifically revealing the GABA A1R subunit overexpression. The identification of the molecular changes along with the Rett syndrome prodromic stages strongly endorses the importance of time frame when addressing this disease, supporting the need for a neurotransmission-targeted early therapeutic intervention.
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Early Postnatal Treatment with Valproate Induces Gad1 Promoter Remodeling in the Brain and Reduces Apnea Episodes in Mecp2-Null Mice. Int J Mol Sci 2019; 20:ijms20205177. [PMID: 31635390 PMCID: PMC6834123 DOI: 10.3390/ijms20205177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 11/17/2022] Open
Abstract
The deletion of Mecp2, the gene encoding methyl-CpG-binding protein 2, causes severe breathing defects and developmental anomalies in mammals. In Mecp2-null mice, impaired GABAergic neurotransmission is demonstrated at the early stage of life. GABAergic dysfunction in neurons in the rostral ventrolateral medulla (RVLM) is considered as a primary cause of breathing abnormality in Mecp2-null mice, but its molecular mechanism is unclear. Here, we report that mRNA expression levels of Gad1, which encodes glutamate decarboxylase 67 (GAD67), in the RVLM of Mecp2-null (Mecp2-/y, B6.129P2(C)-Mecp2tm1.1Bird/J) mice is closely related to the methylation status of its promoter, and valproate (VPA) can upregulate transcription from Gad1 through epigenetic mechanisms. The administration of VPA (300 mg/kg/day) together with L-carnitine (30 mg/kg/day) from day 8 to day 14 after birth increased Gad1 mRNA expression in the RVLM and reduced apnea counts in Mecp2-/y mice on postnatal day 15. Cytosine methylation levels in the Gad1 promoter were higher in the RVLM of Mecp2-/y mice compared to wild-type mice born to C57BL/6J females, while VPA treatment decreased the methylation levels in Mecp2-/y mice. Chromatin immunoprecipitation assay revealed that the VPA treatment reduced the binding of methyl-CpG binding domain protein 1 (MBD1) to the Gad1 promoter in Mecp2-/y mice. These results suggest that VPA improves breathing of Mecp2-/y mice by reducing the Gad1 promoter methylation, which potentially leads to the enhancement of GABAergic neurotransmission in the RVLM.
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Vidal S, Xiol C, Pascual-Alonso A, O'Callaghan M, Pineda M, Armstrong J. Genetic Landscape of Rett Syndrome Spectrum: Improvements and Challenges. Int J Mol Sci 2019; 20:ijms20163925. [PMID: 31409060 PMCID: PMC6719047 DOI: 10.3390/ijms20163925] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/08/2019] [Accepted: 08/10/2019] [Indexed: 02/06/2023] Open
Abstract
Rett syndrome (RTT) is an early-onset neurodevelopmental disorder that primarily affects females, resulting in severe cognitive and physical disabilities, and is one of the most prevalent causes of intellectual disability in females. More than fifty years after the first publication on Rett syndrome, and almost two decades since the first report linking RTT to the MECP2 gene, the research community's effort is focused on obtaining a better understanding of the genetics and the complex biology of RTT and Rett-like phenotypes without MECP2 mutations. Herein, we review the current molecular genetic studies, which investigate the genetic causes of RTT or Rett-like phenotypes which overlap with other genetic disorders and document the swift evolution of the techniques and methodologies employed. This review also underlines the clinical and genetic heterogeneity of the Rett syndrome spectrum and provides an overview of the RTT-related genes described to date, many of which are involved in epigenetic gene regulation, neurotransmitter action or RNA transcription/translation. Finally, it discusses the importance of including both phenotypic and genetic diagnosis to provide proper genetic counselling from a patient's perspective and the appropriate treatment.
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Affiliation(s)
- Silvia Vidal
- Sant Joan de Déu Research Foundation, 08950 Barcelona, Spain
- Institut de Recerca Pediàtrica Hospital Sant Joan de Déu, 08950 Barcelona, Spain
| | - Clara Xiol
- Sant Joan de Déu Research Foundation, 08950 Barcelona, Spain
- Institut de Recerca Pediàtrica Hospital Sant Joan de Déu, 08950 Barcelona, Spain
| | - Ainhoa Pascual-Alonso
- Sant Joan de Déu Research Foundation, 08950 Barcelona, Spain
- Institut de Recerca Pediàtrica Hospital Sant Joan de Déu, 08950 Barcelona, Spain
| | - M O'Callaghan
- Institut de Recerca Pediàtrica Hospital Sant Joan de Déu, 08950 Barcelona, Spain
- Neurology Service, Hospital Sant Joan de Déu, 08950 Barcelona, Spain
- CIBER-ER (Biomedical Network Research Center for Rare Diseases), Institute of Health Carlos III (ISCIII), 28029 Madrid, Spain
| | - Mercè Pineda
- Sant Joan de Déu Research Foundation, 08950 Barcelona, Spain
| | - Judith Armstrong
- Institut de Recerca Pediàtrica Hospital Sant Joan de Déu, 08950 Barcelona, Spain.
- CIBER-ER (Biomedical Network Research Center for Rare Diseases), Institute of Health Carlos III (ISCIII), 28029 Madrid, Spain.
- Molecular and Genetics Medicine Section, Hospital Sant Joan de Déu, 08950 Barcelona, Spain.
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