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Bae HG, Wu WC, Nip K, Gould E, Kim JH. Scn2a deletion disrupts oligodendroglia function: Implication for myelination, neural circuitry, and auditory hypersensitivity in ASD. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.15.589242. [PMID: 38659965 PMCID: PMC11042360 DOI: 10.1101/2024.04.15.589242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Autism spectrum disorder (ASD) is characterized by a complex etiology, with genetic determinants significantly influencing its manifestation. Among these, the Scn2a gene emerges as a pivotal player, crucially involved in both glial and neuronal functionality. This study elucidates the underexplored roles of Scn2a in oligodendrocytes, and its subsequent impact on myelination and auditory neural processes. The results reveal a nuanced interplay between oligodendrocytes and axons, where Scn2a deletion causes alterations in the intricate process of myelination. This disruption, in turn, instigates changes in axonal properties and neuronal activities at the single cell level. Furthermore, oligodendrocyte-specific Scn2a deletion compromises the integrity of neural circuitry within auditory pathways, leading to auditory hypersensitivity-a common sensory abnormality observed in ASD. Through transcriptional profiling, we identified alterations in the expression of myelin-associated genes, highlighting the cellular consequences engendered by Scn2a deletion. In summary, the findings provide unprecedented insights into the pathway from Scn2a deletion in oligodendrocytes to sensory abnormalities in ASD, underscoring the integral role of Scn2a -mediated myelination in auditory responses. This research thereby provides novel insights into the intricate tapestry of genetic and cellular interactions inherent in ASD.
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2
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Ng ACH, Choudhary A, Barrett KT, Gavrilovici C, Scantlebury MH. Mechanisms of infantile epileptic spasms syndrome: What have we learned from animal models? Epilepsia 2024; 65:266-280. [PMID: 38036453 DOI: 10.1111/epi.17841] [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: 10/02/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/02/2023]
Abstract
The devastating developmental and epileptic encephalopathy of infantile epileptic spasms syndrome (IESS) has numerous causes, including, but not limited to, brain injury, metabolic, and genetic conditions. Given the stereotyped electrophysiologic, age-dependent, and clinical findings, there likely exists one or more final common pathways in the development of IESS. The identity of this final common pathway is unknown, but it may represent a novel therapeutic target for infantile spasms. Previous research on IESS has focused largely on identifying the neuroanatomic substrate using specialized neuroimaging techniques and cerebrospinal fluid analysis in human patients. Over the past three decades, several animal models of IESS were created with an aim to interrogate the underlying pathogenesis of IESS, to identify novel therapeutic targets, and to test various treatments. Each of these models have been successful at recapitulating multiple aspects of the human IESS condition. These animal models have implicated several different molecular pathways in the development of infantile spasms. In this review we outline the progress that has been made thus far using these animal models and discuss future directions to help researchers identify novel treatments for drug-resistant IESS.
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Affiliation(s)
- Andy Cheuk-Him Ng
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Anamika Choudhary
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Karlene T Barrett
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Cezar Gavrilovici
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Morris H Scantlebury
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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3
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Yoshida K, Kato D, Sugio S, Takeda I, Wake H. Activity-dependent oligodendrocyte calcium dynamics and their changes in Alzheimer's disease. Front Cell Neurosci 2023; 17:1154196. [PMID: 38026691 PMCID: PMC10644703 DOI: 10.3389/fncel.2023.1154196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023] Open
Abstract
Oligodendrocytes (OCs) form myelin around axons, which is dependent on neuronal activity. This activity-dependent myelination plays a crucial role in training and learning. Previous studies have suggested that neuronal activity regulates proliferation and differentiation of oligodendrocyte precursor cells (OPCs) and myelination. In addition, deficient activity-dependent myelination results in impaired motor learning. However, the functional response of OC responsible for neuronal activity and their pathological changes is not fully elucidated. In this research, we aimed to understand the activity-dependent OC responses and their different properties by observing OCs using in vivo two-photon microscopy. We clarified that the Ca2+ activity in OCs is neuronal activity dependent and differentially regulated by neurotransmitters such as glutamate or adenosine triphosphate (ATP). Furthermore, in 5-month-old mice models of Alzheimer's disease, a period before the appearance of behavioral abnormalities, the elevated Ca2+ responses in OCs are ATP dependent, suggesting that OCs receive ATP from damaged tissue. We anticipate that our research will help in determining the correct therapeutic strategy for neurodegenerative diseases beyond the synapse.
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Affiliation(s)
- Kenji Yoshida
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Daisuke Kato
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Division of Multicellular Circuit Dynamics, National Institute for Physiological Sciences, National Institute of Natural Sciences, Okazaki, Japan
| | - Shouta Sugio
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Division of Multicellular Circuit Dynamics, National Institute for Physiological Sciences, National Institute of Natural Sciences, Okazaki, Japan
| | - Ikuko Takeda
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Division of Multicellular Circuit Dynamics, National Institute for Physiological Sciences, National Institute of Natural Sciences, Okazaki, Japan
| | - Hiroaki Wake
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Division of Multicellular Circuit Dynamics, National Institute for Physiological Sciences, National Institute of Natural Sciences, Okazaki, Japan
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Saitama, Japan
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4
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Bohlen JF, Cleary CM, Das D, Sripathy SR, Sadowski N, Shim G, Kenney RF, Buchler IP, Banerji T, Scanlan TS, Mulkey DK, Maher BJ. Promyelinating drugs promote functional recovery in an autism spectrum disorder mouse model of Pitt-Hopkins syndrome. Brain 2023; 146:3331-3346. [PMID: 37068912 PMCID: PMC10393406 DOI: 10.1093/brain/awad057] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 01/10/2023] [Accepted: 02/03/2023] [Indexed: 04/19/2023] Open
Abstract
Pitt-Hopkins syndrome is an autism spectrum disorder caused by autosomal dominant mutations in the human transcription factor 4 gene (TCF4). One pathobiological process caused by murine Tcf4 mutation is a cell autonomous reduction in oligodendrocytes and myelination. In this study, we show that the promyelinating compounds, clemastine, sobetirome and Sob-AM2 are effective at restoring myelination defects in a Pitt-Hopkins syndrome mouse model. In vitro, clemastine treatment reduced excess oligodendrocyte precursor cells and normalized oligodendrocyte density. In vivo, 2-week intraperitoneal administration of clemastine also normalized oligodendrocyte precursor cell and oligodendrocyte density in the cortex of Tcf4 mutant mice and appeared to increase the number of axons undergoing myelination, as EM imaging of the corpus callosum showed a significant increase in the proportion of uncompacted myelin and an overall reduction in the g-ratio. Importantly, this treatment paradigm resulted in functional rescue by improving electrophysiology and behaviour. To confirm behavioural rescue was achieved via enhancing myelination, we show that treatment with the thyroid hormone receptor agonist sobetirome or its brain penetrating prodrug Sob-AM2, was also effective at normalizing oligodendrocyte precursor cell and oligodendrocyte densities and behaviour in the Pitt-Hopkins syndrome mouse model. Together, these results provide preclinical evidence that promyelinating therapies may be beneficial in Pitt-Hopkins syndrome and potentially other neurodevelopmental disorders characterized by dysmyelination.
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Affiliation(s)
- Joseph F Bohlen
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Colin M Cleary
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT 06269, USA
| | - Debamitra Das
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Srinidhi Rao Sripathy
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Norah Sadowski
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Gina Shim
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Rakaia F Kenney
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Ingrid P Buchler
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
| | - Tapasree Banerji
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Thomas S Scanlan
- Department of Physiology & Pharmacology and Program in Chemical Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Daniel K Mulkey
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT 06269, USA
| | - Brady J Maher
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD 21205, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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Perez-Gianmarco L, Kurt B, Kukley M. Technical approaches and challenges to study AMPA receptors in oligodendrocyte lineage cells: Past, present, and future. Glia 2023; 71:819-847. [PMID: 36453615 DOI: 10.1002/glia.24305] [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: 06/02/2022] [Revised: 11/05/2022] [Accepted: 11/10/2022] [Indexed: 12/03/2022]
Abstract
Receptors for α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPARs) are ligand-gated ionotropic receptors for glutamate that is a major excitatory neurotransmitter in the central nervous system. AMPARs are located at postsynaptic sites of neuronal synapses where they mediate fast synaptic signaling and synaptic plasticity. Remarkably, AMPARs are also expressed by glial cells. Their expression by the oligodendrocyte (OL) lineage cells is of special interest because AMPARs mediate fast synaptic communication between neurons and oligodendrocyte progenitor cells (OPCs), modulate proliferation and differentiation of OPCs, and may also be involved in regulation of myelination. On the other hand, during pathological conditions, AMPARs may mediate damage of the OL lineage cells. In the present review, we focus on the technical approaches that have been used to study AMPARs in the OL lineage cells, and discuss future perspectives of AMPAR research in these glial cells.
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Affiliation(s)
- Lucila Perez-Gianmarco
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neurosciences, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Begüm Kurt
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Department of Neurosciences, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Maria Kukley
- Laboratory of Neuronal and Glial Physiology, Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque - Basque Foundation for Science, Bilbao, Spain
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6
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Wu Y, Tang Z, Zhang J, Wang Y, Liu S. Restoration of spinal cord injury: From endogenous repairing process to cellular therapy. Front Cell Neurosci 2022; 16:1077441. [PMID: 36523818 PMCID: PMC9744968 DOI: 10.3389/fncel.2022.1077441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 11/08/2022] [Indexed: 09/26/2023] Open
Abstract
Spinal cord injury (SCI) disrupts neurological pathways and impacts sensory, motor, and autonomic nerve function. There is no effective treatment for SCI currently. Numerous endogenous cells, including astrocytes, macrophages/microglia, and oligodendrocyte, are involved in the histological healing process following SCI. By interfering with cells during the SCI repair process, some advancements in the therapy of SCI have been realized. Nevertheless, the endogenous cell types engaged in SCI repair and the current difficulties these cells confront in the therapy of SCI are poorly defined, and the mechanisms underlying them are little understood. In order to better understand SCI and create new therapeutic strategies and enhance the clinical translation of SCI repair, we have comprehensively listed the endogenous cells involved in SCI repair and summarized the six most common mechanisms involved in SCI repair, including limiting the inflammatory response, protecting the spared spinal cord, enhancing myelination, facilitating neovascularization, producing neurotrophic factors, and differentiating into neural/colloidal cell lines.
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Affiliation(s)
| | | | | | | | - Shengwen Liu
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Liu W, Tao JC, Zhu SZ, Dai CL, Wang YX, Yu B, Yao C, Sun YY. Expression and regulatory network of long noncoding RNA in rats after spinal cord hemisection injury. Neural Regen Res 2022; 17:2300-2304. [PMID: 35259853 PMCID: PMC9083175 DOI: 10.4103/1673-5374.337052] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/27/2021] [Accepted: 12/14/2021] [Indexed: 11/05/2022] Open
Abstract
Long noncoding RNAs (lncRNAs) participate in a variety of biological processes and diseases. However, the expression and function of lncRNAs after spinal cord injury has not been extensively analyzed. In this study of right side hemisection of the spinal cord at T10, we detected the expression of lncRNAs in the proximal tissue of T10 lamina at different time points and found 445 lncRNAs and 6522 mRNA were differentially expressed. We divided the differentially expressed lncRNAs into 26 expression trends and analyzed Profile 25 and Profile 2, the two expression trends with the most significant difference. Our results showed that the expression of 68 lncRNAs in Profile 25 rose first and remained high 3 days post-injury. There were 387 mRNAs co-expressed with the 68 lncRNAs in Profile 25. The co-expression network showed that the co-expressed genes were mainly enriched in cell division, inflammatory response, FcγR-mediated cell phagocytosis signaling pathway, cell cycle and apoptosis. The expression of 56 lncRNAs in Profile2 first declined and remained low after 3 days post-injury. There were 387 mRNAs co-expressed with the 56 lncRNAs in Profile 2. The co-expression network showed that the co-expressed genes were mainly enriched in the chemical synaptic transmission process and in the signaling pathway of neuroactive ligand-receptor interaction. The results provided the expression and regulatory network of the main lncRNAs after spinal cord injury and clarified their co-expressed gene enriched biological processes and signaling pathways. These findings provide a new direction for the clinical treatment of spinal cord injury.
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Affiliation(s)
- Wei Liu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Jin-Cheng Tao
- Medical College, Nantong University, Nantong, Jiangsu Province, China
| | - Sheng-Ze Zhu
- Medical College, Nantong University, Nantong, Jiangsu Province, China
| | - Chao-Lun Dai
- Medical College, Nantong University, Nantong, Jiangsu Province, China
| | - Ya-Xian Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Bin Yu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Chun Yao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Yu-Yu Sun
- Department of Orthopedics, Nantong Third People’s Hospital, Nantong University, Nantong, Jiangsu Province, China
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8
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Tang X, Li Q, Huang T, Zhang H, Chen X, Ling J, Yang Y. Regenerative Role of T Cells in Nerve Repair and Functional Recovery. Front Immunol 2022; 13:923152. [PMID: 35865551 PMCID: PMC9294345 DOI: 10.3389/fimmu.2022.923152] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/06/2022] [Indexed: 12/17/2022] Open
Abstract
The immune system is essential in the process of nerve repair after injury. Successful modulation of the immune response is regarded as an effective approach to improving treatment outcomes. T cells play an important role in the immune response of the nervous system, and their beneficial roles in promoting regeneration have been increasingly recognized. However, the diversity of T-cell subsets also delivers both neuroprotective and neurodegenerative functions. Therefore, this review mainly discusses the beneficial impact of T-cell subsets in the repair of both peripheral nervous system and central nervous system injuries and introduces studies on various therapies based on T-cell regulation. Further discoveries in T-cell mechanisms and multifunctional biomaterials will provide novel strategies for nerve regeneration.
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Affiliation(s)
- Xiaoxuan Tang
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
- Medical School of Nantong University, Nantong University, Nantong, China
| | - Qiaoyuan Li
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
| | - Tingting Huang
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
| | - Han Zhang
- Medical School of Nantong University, Nantong University, Nantong, China
| | - Xiaoli Chen
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
| | - Jue Ling
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
- *Correspondence: Jue Ling, ; Yumin Yang,
| | - Yumin Yang
- Key Laboratory of Neuroregeneration, Ministry of Education and Jiangsu Province, Co-Innovation Center of Neuroregeneration, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
- *Correspondence: Jue Ling, ; Yumin Yang,
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9
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Chokr SM, Milinkeviciute G, Cramer KS. Synapse Maturation and Developmental Impairment in the Medial Nucleus of the Trapezoid Body. Front Integr Neurosci 2022; 16:804221. [PMID: 35221938 PMCID: PMC8863736 DOI: 10.3389/fnint.2022.804221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/17/2022] [Indexed: 11/29/2022] Open
Abstract
Sound localization requires rapid interpretation of signal speed, intensity, and frequency. Precise neurotransmission of auditory signals relies on specialized auditory brainstem synapses including the calyx of Held, the large encapsulating input to principal neurons in the medial nucleus of the trapezoid body (MNTB). During development, synapses in the MNTB are established, eliminated, and strengthened, thereby forming an excitatory/inhibitory (E/I) synapse profile. However, in neurodevelopmental disorders such as autism spectrum disorder (ASD), E/I neurotransmission is altered, and auditory phenotypes emerge anatomically, molecularly, and functionally. Here we review factors required for normal synapse development in this auditory brainstem pathway and discuss how it is affected by mutations in ASD-linked genes.
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10
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Hiramoto T, Sumiyoshi A, Yamauchi T, Tanigaki K, Shi Q, Kang G, Ryoke R, Nonaka H, Enomoto S, Izumi T, Bhat MA, Kawashima R, Hiroi N. Tbx1, a gene encoded in 22q11.2 copy number variant, is a link between alterations in fimbria myelination and cognitive speed in mice. Mol Psychiatry 2022; 27:929-938. [PMID: 34737458 PMCID: PMC9054676 DOI: 10.1038/s41380-021-01318-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 09/15/2021] [Accepted: 09/23/2021] [Indexed: 12/18/2022]
Abstract
Copy number variants (CNVs) have provided a reliable entry point to identify the structural correlates of atypical cognitive development. Hemizygous deletion of human chromosome 22q11.2 is associated with impaired cognitive function; however, the mechanisms by which the CNVs contribute to cognitive deficits via diverse structural alterations in the brain remain unclear. This study aimed to determine the cellular basis of the link between alterations in brain structure and cognitive functions in mice with a heterozygous deletion of Tbx1, one of the 22q11.2-encoded genes. Ex vivo whole-brain diffusion-tensor imaging (DTI)-magnetic resonance imaging (MRI) in Tbx1 heterozygous mice indicated that the fimbria was the only region with significant myelin alteration. Electron microscopic and histological analyses showed that Tbx1 heterozygous mice exhibited an apparent absence of large myelinated axons and thicker myelin in medium axons in the fimbria, resulting in an overall decrease in myelin. The fimbria of Tbx1 heterozygous mice showed reduced mRNA levels of Ng2, a gene required to produce oligodendrocyte precursor cells. Moreover, postnatal progenitor cells derived from the subventricular zone, a source of oligodendrocytes in the fimbria, produced fewer oligodendrocytes in vitro. Behavioral analyses of these mice showed selectively slower acquisition of spatial memory and cognitive flexibility with no effects on their accuracy or sensory or motor capacities. Our findings provide a genetic and cellular basis for the compromised cognitive speed in patients with 22q11.2 hemizygous deletion.
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Affiliation(s)
- Takeshi Hiramoto
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Akira Sumiyoshi
- Institute of Development, Aging, and Cancer, Tohoku University, 4-1, Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan
- National Institutes for Quantum and Radiological Science and Technology, 4-9-1, Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Takahira Yamauchi
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Kenji Tanigaki
- Research Institute, Shiga Medical Center, 5-4-30 Moriyama, Moriyama-shi, Shiga, Japan
| | - Qian Shi
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Gina Kang
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Rie Ryoke
- Institute of Development, Aging, and Cancer, Tohoku University, 4-1, Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan
| | - Hiroi Nonaka
- Institute of Development, Aging, and Cancer, Tohoku University, 4-1, Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan
| | - Shingo Enomoto
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Takeshi Izumi
- Department of Pharmacology, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsu, Ishikari, Hokkaido, 061-0293, Japan
- Advanced Research Promotion Center, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsu, Ishikari, Hokkaido, 061-0293, Japan
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Ryuta Kawashima
- Institute of Development, Aging, and Cancer, Tohoku University, 4-1, Seiryo-cho, Aoba-ku, Sendai, 980-8575, Japan
| | - Noboru Hiroi
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
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11
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Panagiotakos G, Pasca SP. A matter of space and time: Emerging roles of disease-associated proteins in neural development. Neuron 2022; 110:195-208. [PMID: 34847355 PMCID: PMC8776599 DOI: 10.1016/j.neuron.2021.10.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/11/2021] [Accepted: 10/25/2021] [Indexed: 01/21/2023]
Abstract
Recent genetic studies of neurodevelopmental disorders point to synaptic proteins and ion channels as key contributors to disease pathogenesis. Although many of these proteins, such as the L-type calcium channel Cav1.2 or the postsynaptic scaffolding protein SHANK3, have well-studied functions in mature neurons, new evidence indicates that they may subserve novel, distinct roles in immature cells as the nervous system is assembled in prenatal development. Emerging tools and technologies, including single-cell sequencing and human cellular models of disease, are illuminating differential isoform utilization, spatiotemporal expression, and subcellular localization of ion channels and synaptic proteins in the developing brain compared with the adult, providing new insights into the regulation of developmental processes. We propose that it is essential to consider the temporally distinct and cell-specific roles of these proteins during development and maturity in our framework for understanding neuropsychiatric disorders.
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Affiliation(s)
- Georgia Panagiotakos
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, USA; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA.
| | - Sergiu P Pasca
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA; Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA.
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12
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Chorghay Z, MacFarquhar D, Li VJ, Aufmkolk S, Schohl A, Wiseman PW, Káradóttir RT, Ruthazer ES. Activity-dependent alteration of early myelin ensheathment in a developing sensory circuit. J Comp Neurol 2021; 530:871-885. [PMID: 34599848 DOI: 10.1002/cne.25253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 12/23/2022]
Abstract
Myelination allows for the regulation of conduction velocity, affecting the precise timing of neuronal inputs important for the development and function of brain circuits. In turn, myelination may be altered by changes in experience, neuronal activity, and vesicular release, but the links between sensory experience, corresponding neuronal activity, and resulting alterations in myelination require further investigation. We thus studied the development of myelination in the Xenopus laevis tadpole, a classic model for studies of visual system development and function because it is translucent and visually responsive throughout the formation of its retinotectal system. We begin with a systematic characterization of the timecourse of early myelin ensheathment in the Xenopus retinotectal system using immunohistochemistry of myelin basic protein (MBP) along with third harmonic generation (THG) microscopy, a label-free structural imaging technique. Based on the mid-larval developmental progression of MBP expression in Xenopus, we identified an appropriate developmental window in which to assess the effects of early temporally patterned visual experience on myelin ensheathment. We used calcium imaging of axon terminals in vivo to characterize the responses of retinal ganglion cells over a range of stroboscopic stimulation frequencies. Strobe frequencies that reliably elicited robust versus dampened calcium responses were then presented to animals for 7 d, and differences in the amount of early myelin ensheathment at the optic chiasm were subsequently quantified. This study provides evidence that it is not just the presence but also to the specific temporal properties of sensory stimuli that are important for myelin plasticity.
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Affiliation(s)
- Zahraa Chorghay
- Montreal Neurological Institute-Hospital and Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
| | - David MacFarquhar
- Department of Chemistry, Otto Maass Building, McGill University, Montréal, QC, Canada.,Department of Physics, Otto Maass Building, McGill University, Montréal, QC, Canada
| | - Vanessa J Li
- Montreal Neurological Institute-Hospital and Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
| | - Sarah Aufmkolk
- Montreal Neurological Institute-Hospital and Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.,Department of Chemistry, Otto Maass Building, McGill University, Montréal, QC, Canada.,Department of Physics, Otto Maass Building, McGill University, Montréal, QC, Canada
| | - Anne Schohl
- Montreal Neurological Institute-Hospital and Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
| | - Paul W Wiseman
- Department of Chemistry, Otto Maass Building, McGill University, Montréal, QC, Canada.,Department of Physics, Otto Maass Building, McGill University, Montréal, QC, Canada
| | - Ragnhildur Thóra Káradóttir
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.,Department of Physiology, BioMedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Edward S Ruthazer
- Montreal Neurological Institute-Hospital and Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
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13
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Gould E, Kim JH. SCN2A contributes to oligodendroglia excitability and development in the mammalian brain. Cell Rep 2021; 36:109653. [PMID: 34496232 PMCID: PMC8486143 DOI: 10.1016/j.celrep.2021.109653] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 05/04/2021] [Accepted: 08/12/2021] [Indexed: 01/21/2023] Open
Abstract
Spiking immature oligodendrocytes (OLs), referred to as spiking OLs, express voltage-activated Na+ channels (Nav) and K+ (Kv) channels, endowing a subpopulation of OLs with the ability to generate Nav-driven spikes. In this study, we investigate the molecular profile of spiking OLs, using single-cell transcriptomics paired with whole-cell patch-clamp recordings. SCN2A, which encodes the channel Nav1.2, is specifically expressed in spiking OLs in the brainstem and cerebellum, both in mice and in Olive baboons. Spiking OLs express lineage markers of OL progenitor cells (OPCs) and pre-myelinating OLs, indicating they belong to a transitional stage during differentiation. Deletion of SCN2A reduces the Nav current-expressing OL population and eliminates spiking OLs, indicating that SCN2A is essential for spiking in OLs. Deletion of SCN2A does not impact global OL proliferation but disrupts maturation of a subpopulation of OLs, suggesting that Nav1.2 is involved in heterogeneity in OL lineage cells and their development.
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Affiliation(s)
- Elizabeth Gould
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Jun Hee Kim
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, TX 78229, USA,Lead contact,Correspondence:
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14
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Liang L, Fazel Darbandi S, Pochareddy S, Gulden FO, Gilson MC, Sheppard BK, Sahagun A, An JY, Werling DM, Rubenstein JLR, Sestan N, Bender KJ, Sanders SJ. Developmental dynamics of voltage-gated sodium channel isoform expression in the human and mouse brain. Genome Med 2021; 13:135. [PMID: 34425903 PMCID: PMC8383430 DOI: 10.1186/s13073-021-00949-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 08/05/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genetic variants in the voltage-gated sodium channels SCN1A, SCN2A, SCN3A, and SCN8A are leading causes of epilepsy, developmental delay, and autism spectrum disorder. The mRNA splicing patterns of all four genes vary across development in the rodent brain, including mutually exclusive copies of the fifth protein-coding exon detected in the neonate (5N) and adult (5A). A second pair of mutually exclusive exons is reported in SCN8A only (18N and 18A). We aimed to quantify the expression of individual exons in the developing human brain. METHODS RNA-seq data from 783 human brain samples across development were analyzed to estimate exon-level expression. Developmental changes in exon utilization were validated by assessing intron splicing. Exon expression was also estimated in RNA-seq data from 58 developing mouse neocortical samples. RESULTS In the mature human neocortex, exon 5A is consistently expressed at least 4-fold higher than exon 5N in all four genes. For SCN2A, SCN3A, and SCN8A, a brain-wide synchronized 5N to 5A transition occurs between 24 post-conceptual weeks (2nd trimester) and 6 years of age. In mice, the equivalent 5N to 5A transition begins at or before embryonic day 15.5. In SCN8A, over 90% of transcripts in the mature human cortex include exon 18A. Early in fetal development, most transcripts include 18N or skip both 18N and 18A, with a transition to 18A inclusion occurring from 13 post-conceptual weeks to 6 months of age. No other protein-coding exons showed comparably dynamic developmental trajectories. CONCLUSIONS Exon usage in SCN1A, SCN2A, SCN3A, and SCN8A changes dramatically during human brain development. These splice isoforms, which alter the biophysical properties of the encoded channels, may account for some of the observed phenotypic differences across development and between specific variants. Manipulation of the proportion of splicing isoforms at appropriate stages of development may act as a therapeutic strategy for specific mutations or even epilepsy in general.
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Affiliation(s)
- Lindsay Liang
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Siavash Fazel Darbandi
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Sirisha Pochareddy
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Forrest O Gulden
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Michael C Gilson
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Brooke K Sheppard
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Atehsa Sahagun
- Department of Neurology, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Joon-Yong An
- School of Biosystem and Biomedical Science, College of Health Science, Korea University, Seoul, 02841, Republic of Korea
| | - Donna M Werling
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - John L R Rubenstein
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair and Yale Child Study Center, Yale School of Medicine, New Haven, CT, 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Comparative Medicine, Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Kevin J Bender
- Department of Neurology, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Stephan J Sanders
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA.
- Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, 94158, USA.
- Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, CA, 94158, USA.
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15
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Boscia F, Elkjaer ML, Illes Z, Kukley M. Altered Expression of Ion Channels in White Matter Lesions of Progressive Multiple Sclerosis: What Do We Know About Their Function? Front Cell Neurosci 2021; 15:685703. [PMID: 34276310 PMCID: PMC8282214 DOI: 10.3389/fncel.2021.685703] [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: 03/13/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
Despite significant advances in our understanding of the pathophysiology of multiple sclerosis (MS), knowledge about contribution of individual ion channels to axonal impairment and remyelination failure in progressive MS remains incomplete. Ion channel families play a fundamental role in maintaining white matter (WM) integrity and in regulating WM activities in axons, interstitial neurons, glia, and vascular cells. Recently, transcriptomic studies have considerably increased insight into the gene expression changes that occur in diverse WM lesions and the gene expression fingerprint of specific WM cells associated with secondary progressive MS. Here, we review the ion channel genes encoding K+, Ca2+, Na+, and Cl- channels; ryanodine receptors; TRP channels; and others that are significantly and uniquely dysregulated in active, chronic active, inactive, remyelinating WM lesions, and normal-appearing WM of secondary progressive MS brain, based on recently published bulk and single-nuclei RNA-sequencing datasets. We discuss the current state of knowledge about the corresponding ion channels and their implication in the MS brain or in experimental models of MS. This comprehensive review suggests that the intense upregulation of voltage-gated Na+ channel genes in WM lesions with ongoing tissue damage may reflect the imbalance of Na+ homeostasis that is observed in progressive MS brain, while the upregulation of a large number of voltage-gated K+ channel genes may be linked to a protective response to limit neuronal excitability. In addition, the altered chloride homeostasis, revealed by the significant downregulation of voltage-gated Cl- channels in MS lesions, may contribute to an altered inhibitory neurotransmission and increased excitability.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", Naples, Italy
| | - Maria Louise Elkjaer
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Zsolt Illes
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Maria Kukley
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque Basque Foundation for Science, Bilbao, Spain
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16
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Sancho L, Contreras M, Allen NJ. Glia as sculptors of synaptic plasticity. Neurosci Res 2021; 167:17-29. [PMID: 33316304 PMCID: PMC8513541 DOI: 10.1016/j.neures.2020.11.005] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022]
Abstract
Glial cells are non-neuronal cells in the nervous system that are crucial for proper brain development and function. Three major classes of glia in the central nervous system (CNS) include astrocytes, microglia and oligodendrocytes. These cells have dynamic morphological and functional properties and constantly surveil neural activity throughout life, sculpting synaptic plasticity. Astrocytes form part of the tripartite synapse with neurons and perform many homeostatic functions essential to proper synaptic function including clearing neurotransmitter and regulating ion balance; they can modify these properties, in addition to additional mechanisms such as gliotransmitter release, to influence short- and long-term plasticity. Microglia, the resident macrophage of the CNS, monitor synaptic activity and can eliminate synapses by phagocytosis or modify synapses by release of cytokines or neurotrophic factors. Oligodendrocytes regulate speed of action potential conduction and efficiency of information exchange through the formation of myelin, having important consequences for the plasticity of neural circuits. A deeper understanding of how glia modulate synaptic and circuit plasticity will further our understanding of the ongoing changes that take place throughout life in the dynamic environment of the CNS.
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Affiliation(s)
- Laura Sancho
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Minerva Contreras
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Nicola J Allen
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd, La Jolla, CA, 92037, USA.
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17
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Ma X, Shi Y. Whether erythropoietin can be a neuroprotective agent against premature brain injury: cellular mechanisms and clinical efficacy. Curr Neuropharmacol 2021; 20:611-629. [PMID: 34030616 DOI: 10.2174/1570159x19666210524154519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 04/27/2021] [Accepted: 05/08/2021] [Indexed: 11/22/2022] Open
Abstract
Preterm infants are at high risk of brain injury. With more understanding of the preterm brain injury's pathogenesis, neuroscientists are looking for more effective methods to prevent and treat it, among which erythropoietin (Epo) is considered as a prime candidate. This review tries to clarify the possible mechanisms of Epo in preterm neuroprotection and summarize updated evidence considering Epo as a pharmacological neuroprotective strategy in animal models and clinical trials. To date, various animal models have validated that Epo is an anti-apoptotic, anti-inflammatory, anti-oxidant, anti-excitotoxic, neurogenetic, erythropoietic, angiogenetic, and neurotrophic agent, thus preventing preterm brain injury. However, although the scientific rationale and preclinical data for Epo's neuroprotective effect are promising, when translated to bedside, the results vary in different studies, especially in its long-term efficacy. Based on existing evidence, it is still too early to recommend Epo as the standard treatment for preterm brain injury.
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Affiliation(s)
- Xueling Ma
- Department of Neonatology, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing 400014, China
| | - Yuan Shi
- Department of Neonatology, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing 400014, China
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18
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GluA2 overexpression in oligodendrocyte progenitors promotes postinjury oligodendrocyte regeneration. Cell Rep 2021; 35:109147. [PMID: 34010640 PMCID: PMC8185898 DOI: 10.1016/j.celrep.2021.109147] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/28/2020] [Accepted: 04/27/2021] [Indexed: 01/18/2023] Open
Abstract
Oligodendrocyte precursor cells (OPCs) are essential for developmental myelination and oligodendrocyte regeneration after CNS injury. These progenitors express calcium-permeable AMPA receptors (AMPARs) and form direct synapses with neurons throughout the CNS, but the roles of this signaling are unclear. To enable selective alteration of the properties of AMPARs in oligodendroglia, we generate mice that allow cell-specific overexpression of EGFP-GluA2 in vivo. In healthy conditions, OPC-specific GluA2 overexpression significantly increase their proliferation in an age-dependent manner but did not alter their rate of differentiation into oligodendrocytes. In contrast, after demyelinating brain injury in neonates or adults, higher GluA2 levels promote both OPC proliferation and oligodendrocyte regeneration, but do not prevent injury-induced initial cell loss. These findings indicate that AMPAR GluA2 content regulates the proliferative and regenerative behavior of adult OPCs, serving as a putative target for better myelin repair.
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19
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Kohrman DC, Borges BC, Cassinotti LR, Ji L, Corfas G. Axon-glia interactions in the ascending auditory system. Dev Neurobiol 2021; 81:546-567. [PMID: 33561889 DOI: 10.1002/dneu.22813] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 11/25/2020] [Accepted: 02/05/2021] [Indexed: 11/09/2022]
Abstract
The auditory system detects and encodes sound information with high precision to provide a high-fidelity representation of the environment and communication. In mammals, detection occurs in the peripheral sensory organ (the cochlea) containing specialized mechanosensory cells (hair cells) that initiate the conversion of sound-generated vibrations into action potentials in the auditory nerve. Neural activity in the auditory nerve encodes information regarding the intensity and frequency of sound stimuli, which is transmitted to the auditory cortex through the ascending neural pathways. Glial cells are critical for precise control of neural conduction and synaptic transmission throughout the pathway, allowing for the precise detection of the timing, frequency, and intensity of sound signals, including the sub-millisecond temporal fidelity is necessary for tasks such as sound localization, and in humans, for processing complex sounds including speech and music. In this review, we focus on glia and glia-like cells that interact with hair cells and neurons in the ascending auditory pathway and contribute to the development, maintenance, and modulation of neural circuits and transmission in the auditory system. We also discuss the molecular mechanisms of these interactions, their impact on hearing and on auditory dysfunction associated with pathologies of each cell type.
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Affiliation(s)
- David C Kohrman
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Beatriz C Borges
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Luis R Cassinotti
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Lingchao Ji
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Gabriel Corfas
- Department of Otolaryngology - Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
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20
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Puñal VM, Ahmed M, Thornton-Kolbe EM, Clowney EJ. Untangling the wires: development of sparse, distributed connectivity in the mushroom body calyx. Cell Tissue Res 2021; 383:91-112. [PMID: 33404837 PMCID: PMC9835099 DOI: 10.1007/s00441-020-03386-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/07/2020] [Indexed: 01/16/2023]
Abstract
Appropriate perception and representation of sensory stimuli pose an everyday challenge to the brain. In order to represent the wide and unpredictable array of environmental stimuli, principle neurons of associative learning regions receive sparse, combinatorial sensory inputs. Despite the broad role of such networks in sensory neural circuits, the developmental mechanisms underlying their emergence are not well understood. As mammalian sensory coding regions are numerically complex and lack the accessibility of simpler invertebrate systems, we chose to focus this review on the numerically simpler, yet functionally similar, Drosophila mushroom body calyx. We bring together current knowledge about the cellular and molecular mechanisms orchestrating calyx development, in addition to drawing insights from literature regarding construction of sparse wiring in the mammalian cerebellum. From this, we formulate hypotheses to guide our future understanding of the development of this critical perceptual center.
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Affiliation(s)
- Vanessa M. Puñal
- Department of Molecular, Cellular & Developmental Biology, The University of Michigan, Ann Arbor, MI 48109, USA,Department of Molecular & Integrative Physiology, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Maria Ahmed
- Department of Molecular, Cellular & Developmental Biology, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Emma M. Thornton-Kolbe
- Department of Molecular, Cellular & Developmental Biology, The University of Michigan, Ann Arbor, MI 48109, USA,Neuroscience Graduate Program, The University of Michigan, Ann Arbor, MI 48109, USA
| | - E. Josephine Clowney
- Department of Molecular, Cellular & Developmental Biology, The University of Michigan, Ann Arbor, MI 48109, USA
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21
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Cherchi F, Pugliese AM, Coppi E. Oligodendrocyte precursor cell maturation: role of adenosine receptors. Neural Regen Res 2021; 16:1686-1692. [PMID: 33510056 PMCID: PMC8328763 DOI: 10.4103/1673-5374.306058] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Oligodendrocyte-formed myelin sheaths allow fast synaptic transmission in the brain and their degeneration leads to demyelinating diseases such as multiple sclerosis. Remyelination requires the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes but, in chronic neurodegenerative disorders, remyelination fails due to adverse environment. Therefore, a strategy to prompt oligodendrocyte progenitor cell differentiation towards myelinating oligodendrocytes is required. The neuromodulator adenosine, and its receptors (A1, A2A, A2B and A3 receptors: A1R, A2AR, A2BR and A3R), are crucial mediators in remyelination processes. It is known that A1Rs facilitate oligodendrocyte progenitor cell maturation and migration whereas the A3Rs initiates apoptosis in oligodendrocyte progenitor cells. Our group of research contributed to the field by demonstrating that A2AR and A2BR inhibit oligodendrocyte progenitor cell maturation by reducing voltage-dependent K+ currents necessary for cell differentiation. The present review summarizes the possible role of adenosine receptor ligands as potential therapeutic targets in demyelinating pathologies such as multiple sclerosis.
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Affiliation(s)
- Federica Cherchi
- Department of Neuroscience, Psychology, Drug Research and Child Health-Neurofarba-Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Anna Maria Pugliese
- Department of Neuroscience, Psychology, Drug Research and Child Health-Neurofarba-Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Elisabetta Coppi
- Department of Neuroscience, Psychology, Drug Research and Child Health-Neurofarba-Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
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22
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Abstract
During development and adulthood, the normal activity of the auditory nerve plays a critical role in the maintenance of both fundamental structural, molecular, and functional parameters of auditory nerve synapses, and the postsynaptic excitatory or inhibitory neurons within the cochlear nucleus (CN). In addition, normal activity within the synaptic circuits of the CN is key to developing and maintaining appropriate synapse connectivity as well as the initiation of binaural sound processing in the superior olivary complex (SOC). Development plays a critical role in the proper neuronal connectivity and establishes a topographic map along the entire auditory pathway. Furthermore, evidence shows that neurons and synaptic circuits in the auditory brainstem are not hard-wired, but instead are plastic in response to hearing deficits. Whether this plasticity in response to hearing loss is compensatory or pathological is still unknown.
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Affiliation(s)
- María Eulalia Rubio
- Departments of Neurobiology and Otolaryngology, University of Pittsburgh, School of Medicine, BST3 Building, room #10016, 3501 Fifth Venue, Pittsburgh, PA, 15261
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23
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High-Frequency Microdomain Ca 2+ Transients and Waves during Early Myelin Internode Remodeling. Cell Rep 2020; 26:182-191.e5. [PMID: 30605675 PMCID: PMC6316190 DOI: 10.1016/j.celrep.2018.12.039] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 11/09/2018] [Accepted: 12/07/2018] [Indexed: 11/25/2022] Open
Abstract
Ensheathment of axons by myelin is a highly complex and multi-cellular process. Cytosolic calcium (Ca2+) changes in the myelin sheath have been implicated in myelin synthesis, but the source of this Ca2+ and the role of neuronal activity is not well understood. Using one-photon Ca2+ imaging, we investigated myelin sheath formation in the mouse somatosensory cortex and found a high rate of spontaneous microdomain Ca2+ transients and large-amplitude Ca2+ waves propagating along the internode. The frequency of Ca2+ transients and waves rapidly declines with maturation and reactivates during remyelination. Unexpectedly, myelin microdomain Ca2+ transients occur independent of neuronal action potential generation or network activity but are nearly completely abolished when the mitochondrial permeability transition pores are blocked. These findings are supported by the discovery of mitochondria organelles in non-compacted myelin. Together, the results suggest that myelin microdomain Ca2+ signals are cell-autonomously driven by high activity of mitochondria during myelin remodeling. Developing myelin sheaths show high rates of calcium transients and calcium waves Myelin calcium transients are independent from neuronal activity Adaxonal and paranodal myelin contained mitochondria Calcium transients require opening of mitochondrial permeability transition pores
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24
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Stedehouder J, Brizee D, Slotman JA, Pascual-Garcia M, Leyrer ML, Bouwen BL, Dirven CM, Gao Z, Berson DM, Houtsmuller AB, Kushner SA. Local axonal morphology guides the topography of interneuron myelination in mouse and human neocortex. eLife 2019; 8:48615. [PMID: 31742557 PMCID: PMC6927753 DOI: 10.7554/elife.48615] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 11/18/2019] [Indexed: 12/30/2022] Open
Abstract
GABAergic fast-spiking parvalbumin-positive (PV) interneurons are frequently myelinated in the cerebral cortex. However, the factors governing the topography of cortical interneuron myelination remain incompletely understood. Here, we report that segmental myelination along neocortical interneuron axons is strongly predicted by the joint combination of interbranch distance and local axon caliber. Enlargement of PV+ interneurons increased axonal myelination, while reduced cell size led to decreased myelination. Next, we considered regular-spiking SOM+ cells, which normally have relatively shorter interbranch distances and thinner axon diameters than PV+ cells, and are rarely myelinated. Consistent with the importance of axonal morphology for guiding interneuron myelination, enlargement of SOM+ cell size dramatically increased the frequency of myelinated axonal segments. Lastly, we confirm that these findings also extend to human neocortex by quantifying interneuron axonal myelination from ex vivo surgical tissue. Together, these findings establish a predictive model of neocortical GABAergic interneuron myelination determined by local axonal morphology.
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Affiliation(s)
- Jeffrey Stedehouder
- Department of Psychiatry, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Demi Brizee
- Department of Psychiatry, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Johan A Slotman
- Erasmus Optical Imaging Center, Department of Pathology, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Maria Pascual-Garcia
- Department of Psychiatry, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Megan L Leyrer
- Department of Neuroscience, Brown University, Providence, United States
| | - Bibi Lj Bouwen
- Department of Neuroscience, Erasmus MC University Medical Center, Rotterdam, Netherlands.,Department of Neurosurgery, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Clemens Mf Dirven
- Department of Neurosurgery, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Zhenyu Gao
- Department of Neuroscience, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - David M Berson
- Department of Neuroscience, Brown University, Providence, United States
| | - Adriaan B Houtsmuller
- Erasmus Optical Imaging Center, Department of Pathology, Erasmus MC University Medical Center, Rotterdam, Netherlands
| | - Steven A Kushner
- Department of Psychiatry, Erasmus MC University Medical Center, Rotterdam, Netherlands
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25
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Velasco-Estevez M, Gadalla KKE, Liñan-Barba N, Cobb S, Dev KK, Sheridan GK. Inhibition of Piezo1 attenuates demyelination in the central nervous system. Glia 2019; 68:356-375. [PMID: 31596529 DOI: 10.1002/glia.23722] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 08/15/2019] [Accepted: 09/06/2019] [Indexed: 12/12/2022]
Abstract
Piezo1 is a mechanosensitive ion channel that facilitates the translation of extracellular mechanical cues to intracellular molecular signaling cascades through a process termed, mechanotransduction. In the central nervous system (CNS), mechanically gated ion channels are important regulators of neurodevelopmental processes such as axon guidance, neural stem cell differentiation, and myelination of axons by oligodendrocytes. Here, we present evidence that pharmacologically mediated overactivation of Piezo1 channels negatively regulates CNS myelination. Moreover, we found that the peptide GsMTx4, an antagonist of mechanosensitive cation channels such as Piezo1, is neuroprotective and prevents chemically induced demyelination. In contrast, the positive modulator of Piezo1 channel opening, Yoda-1, induces demyelination and neuronal damage. Using an ex vivo murine-derived organotypic cerebellar slice culture model, we demonstrate that GsMTx4 attenuates demyelination induced by the cytotoxic lipid, psychosine. Importantly, we confirmed the potential therapeutic effects of GsMTx4 peptide in vivo by co-administering it with lysophosphatidylcholine (LPC), via stereotactic injection, into the cerebral cortex of adult mice. GsMTx4 prevented both demyelination and neuronal damage usually caused by the intracortical injection of LPC in vivo; a well-characterized model of focal demyelination. GsMTx4 also attenuated both LPC-induced astrocyte toxicity and microglial reactivity within the lesion core. Overall, our data suggest that pharmacological activation of Piezo1 channels induces demyelination and that inhibition of mechanosensitive channels, using GsMTx4, may alleviate the secondary progressive neurodegeneration often present in the latter stages of demyelinating diseases.
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Affiliation(s)
- María Velasco-Estevez
- Drug Development, School of Medicine, Trinity College Dublin, Dublin, Ireland.,School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
| | - Kamal K E Gadalla
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Núria Liñan-Barba
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
| | - Stuart Cobb
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Kumlesh K Dev
- Drug Development, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Graham K Sheridan
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK.,School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK
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26
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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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27
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Barron T, Kim JH. Neuronal input triggers Ca 2+ influx through AMPA receptors and voltage-gated Ca 2+ channels in oligodendrocytes. Glia 2019; 67:1922-1932. [PMID: 31313856 PMCID: PMC6771819 DOI: 10.1002/glia.23670] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 06/13/2019] [Accepted: 06/18/2019] [Indexed: 12/25/2022]
Abstract
Communication between neurons and developing oligodendrocytes (OLs) leading to OL Ca2+ rise is critical for axon myelination and OL development. Here, we investigate signaling factors and sources of Ca2+ rise in OLs in the mouse brainstem. Glutamate puff or axon fiber stimulation induces a Ca2+ rise in pre‐myelinating OLs, which is primarily mediated by Ca2+‐permeable AMPA receptors. During glutamate application, inward currents via AMPA receptors and elevated extracellular K+ caused by increased neuronal activity collectively lead to OL depolarization, triggering Ca2+ influx via P/Q‐ and L‐type voltage‐gated Ca2+ (Cav) channels. Thus, glutamate is a key signaling factor in dynamic communication between neurons and OLs that triggers Ca2+ transients via AMPARs and Cav channels in developing OLs. The results provide a mechanism for OL Ca2+ dynamics in response to neuronal input, which has implications for OL development and myelination.
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Affiliation(s)
- Tara Barron
- Department of Cellular and Integrative Physiology, UT Health San Antonio, San Antonio, Texas
| | - Jun Hee Kim
- Department of Cellular and Integrative Physiology, UT Health San Antonio, San Antonio, Texas
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28
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Volpe JJ. Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions. Pediatr Neurol 2019; 95:42-66. [PMID: 30975474 DOI: 10.1016/j.pediatrneurol.2019.02.016] [Citation(s) in RCA: 167] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/12/2019] [Accepted: 02/19/2019] [Indexed: 02/07/2023]
Abstract
Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.
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Affiliation(s)
- Joseph J Volpe
- Department of Neurology, Harvard Medical School, Boston, Massachusetts; Department of Pediatric Newborn Medicine, Harvard Medical School, Boston, Massachusetts.
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29
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Jang M, Gould E, Xu J, Kim EJ, Kim JH. Oligodendrocytes regulate presynaptic properties and neurotransmission through BDNF signaling in the mouse brainstem. eLife 2019; 8:42156. [PMID: 30998186 PMCID: PMC6504230 DOI: 10.7554/elife.42156] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 04/17/2019] [Indexed: 12/17/2022] Open
Abstract
Neuron–glia communication contributes to the fine-tuning of synaptic functions. Oligodendrocytes near synapses detect and respond to neuronal activity, but their role in synapse development and plasticity remains largely unexplored. We show that oligodendrocytes modulate neurotransmitter release at presynaptic terminals through secretion of brain-derived neurotrophic factor (BDNF). Oligodendrocyte-derived BDNF functions via presynaptic tropomyosin receptor kinase B (TrkB) to ensure fast, reliable neurotransmitter release and auditory transmission in the developing brain. In auditory brainstem slices from Bdnf+/– mice, reduction in endogenous BDNF significantly decreased vesicular glutamate release by reducing the readily releasable pool of glutamate vesicles, without altering presynaptic Ca2+ channel activation or release probability. Using conditional knockout mice, cell-specific ablation of BDNF in oligodendrocytes largely recapitulated this effect, which was recovered by BDNF or TrkB agonist application. This study highlights a novel function for oligodendrocytes in synaptic transmission and their potential role in the activity-dependent refinement of presynaptic properties.
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Affiliation(s)
- Miae Jang
- The Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, United States
| | - Elizabeth Gould
- The Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, United States
| | - Jie Xu
- The Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, United States.,Children's Medical Center, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Eun Jung Kim
- The Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, United States
| | - Jun Hee Kim
- The Department of Cellular and Integrative Physiology, University of Texas Health Science Center, San Antonio, United States
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30
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Dingman AL, Rodgers KM, Dietz RM, Hickey SP, Frazier AP, Clevenger AC, Yonchek JC, Traystman RJ, Macklin WB, Herson PS. Oligodendrocyte Progenitor Cell Proliferation and Fate after White Matter Stroke in Juvenile and Adult Mice. Dev Neurosci 2019; 40:1-16. [PMID: 30861520 DOI: 10.1159/000496200] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 12/06/2018] [Indexed: 11/19/2022] Open
Abstract
The incidence of stroke in children is 2.4 per 100,000 person-years and results in long-term motor and cognitive disability. In ischemic stroke, white matter (WM) is frequently injured, but is relatively understudied compared to grey matter injury. Previous research suggests that the cellular response to WM ischemic injury is different at different ages. Little is known about whether WM repair mechanisms differ in children and adults. We utilized a model of focal ischemic WM injury to determine the oligodendrocyte (OL) response to focal WM ischemic injury in juvenile and adult mice. Methods: Juvenile (21-25 days of age) versus adult (2-3 months of age) mice underwent stereotaxic injection of the potent vasoconstrictor N5-(1-iminoethyhl)-L-ornithine (L-NIO) into the lateral corpus callosum (CC). Animals were sacrificed on postoperative day 3 (acute) or 21 (chronic). Cell birth-dating was performed acutely after WM stroke with 5-ethynyl-2-deoxyuridine (EdU) injected intraperitoneally. Immunohistochemistry was performed, as well as stereology, to measure injury volume. The acute oligodendrocyte progenitor cell (OPC) proliferation and the chronic OL cell fate were determined with immunohistochemistry. Compound action potentials were measured in the CC at acute and chronic time points. Results: Acutely WM injury volume was smaller in juveniles. There was significantly greater OPC proliferation in juvenile animals (acute) compared to adults, but newly born OLs did not survive and mature into myelinating cells at chronic time points. In addition, juveniles did not have improved histological or functional recovery when compared to adults. Protecting newly born OPCs is a potential therapeutic target in children with ischemic stroke.
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Affiliation(s)
- Andra L Dingman
- Division of Child Neurology, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA,
| | - Krista M Rodgers
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Robert M Dietz
- Division of Neonatology, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Sean P Hickey
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexandra P Frazier
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Amy C Clevenger
- Division of Critical Care Medicine, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Joan C Yonchek
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Richard J Traystman
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Wendy B Macklin
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Paco S Herson
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, USA
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31
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Chorghay Z, Káradóttir RT, Ruthazer ES. White Matter Plasticity Keeps the Brain in Tune: Axons Conduct While Glia Wrap. Front Cell Neurosci 2018; 12:428. [PMID: 30519159 PMCID: PMC6251003 DOI: 10.3389/fncel.2018.00428] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Accepted: 10/30/2018] [Indexed: 12/28/2022] Open
Abstract
Precise timing of neuronal inputs is crucial for brain circuit function and development, where it contributes critically to experience-dependent plasticity. Myelination therefore provides an important adaptation mechanism for vertebrate circuits. Despite its importance to circuit activity, the interplay between neuronal activity and myelination has yet to be fully elucidated. In recent years, significant attention has been devoted to uncovering and explaining the phenomenon of white matter (WM) plasticity. Here, we summarize some of the critical evidence for modulation of the WM by neuronal activity, ranging from human diffusion tensor imaging (DTI) studies to experiments in animal models. These experiments reveal activity-dependent changes in the differentiation and proliferation of the oligodendrocyte lineage, and in the critical properties of the myelin sheaths. We discuss the implications of such changes for synaptic function and plasticity, and present the underlying mechanisms of neuron–glia communication, with a focus on glutamatergic signaling and the axomyelinic synapse. Finally, we examine evidence that myelin plasticity may be subject to critical periods. Taken together, the present review aims to provide insights into myelination in the context of brain circuit formation and function, emphasizing the bidirectional interplay between neurons and myelinating glial cells to better inform future investigations of nervous system plasticity.
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Affiliation(s)
- Zahraa Chorghay
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Ragnhildur Thóra Káradóttir
- Department of Veterinary Medicine, Wellcome Trust - Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Edward S Ruthazer
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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