1
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Bishop A, Romero JC, Tonapi S, Parihar M, Loranc E, Miller H, Lawrence L, Bassani N, Robledo D, Cao L, Nie J, Kanda K, Stoja A, Garcia N, Gorthi A, Stoveken B, Lane A, Fan T, Cassel T, Zha S, Musi N. ATM phosphorylation of CD98HC increases antiporter membrane localization and prevents chronic toxic glutamate accumulation in Ataxia telangiectasia. RESEARCH SQUARE 2024:rs.3.rs-4947457. [PMID: 39281865 PMCID: PMC11398575 DOI: 10.21203/rs.3.rs-4947457/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/18/2024]
Abstract
Ataxia telangiectasia (A-T) is a rare genetic disorder characterized by neurological defects, immunodeficiency, cancer predisposition, radiosensitivity, decreased blood vessel integrity, and diabetes. ATM, the protein mutated in A-T, responds to DNA damage and oxidative stress, but its functional relationship to the progressive clinical manifestation of A-T is not understood. CD98HC chaperones cystine/glutamate (x c - ) and cationic/neutral amino acid (y + L) antiporters to the cell membrane, and CD98HC phosphorylation by ATM accelerates membrane localization to acutely increase amino acid transport. Loss of ATM impacts tissues reliant on SLC family antiporters relevant to A-T phenotypes, such as endothelial cells (telangiectasia) and pancreatic α-cells (fatty liver and diabetes) with toxic glutamate accumulation. Bypassing the antiporters restores intracellular metabolic balance both in ATM-deficient cells and mouse models. These findings provide new insight into the long-known benefits of N-acetyl cysteine to A-T cells beyond oxidative stress through removing excess glutamate by production of glutathione.
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2
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Kim H, Choi S, Lee E, Koh W, Lee CJ. Tonic NMDA Receptor Currents in the Brain: Regulation and Cognitive Functions. Biol Psychiatry 2024; 96:164-175. [PMID: 38490367 DOI: 10.1016/j.biopsych.2024.03.009] [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: 10/24/2023] [Revised: 02/20/2024] [Accepted: 03/04/2024] [Indexed: 03/17/2024]
Abstract
Synaptically localized NMDA receptors (NMDARs) play a crucial role in important cognitive functions by mediating synaptic transmission and plasticity. In contrast, a tonic NMDAR current, thought to be mediated by extrasynaptic NMDARs, has a less clear function. This review provides a comprehensive overview of tonic NMDAR currents, focusing on their roles in synaptic transmission/plasticity and their impact on cognitive functions and psychiatric disorders. We discuss the roles of 3 endogenous ligands (i.e., glutamate, glycine, and D-serine) and receptors in mediating tonic NMDAR currents and explore the diverse mechanisms that regulate tonic NMDAR currents. In light of recent controversies surrounding the source of D-serine, we highlight the recent findings suggesting that astrocytes release D-serine to modulate tonic NMDAR currents and control cognitive flexibility. Furthermore, we propose distinct roles of neuronal and astrocytic D-serine in different locations and their implications for synaptic regulation and cognitive functions. The potential roles of tonic NMDAR currents in various psychiatric disorders, such as schizophrenia and autism spectrum disorder, are discussed in the context of the NMDAR hypofunction hypothesis. By presenting the mechanisms by which various cells, particularly astrocytes, regulate tonic NMDAR currents, we aim to stimulate future research in NMDAR hypofunction- or hyperfunction-related psychiatric disorders. This review not only provides a better understanding of the complex interplay between tonic NMDAR currents and cognitive functions but also sheds light on its potential therapeutic target for the treatment of various psychiatric disorders.
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Affiliation(s)
- Hayoung Kim
- Center for Cognition and Sociality, Life Science Institute, Institute for Basic Science, Daejeon, South Korea
| | - Sunyeong Choi
- Center for Cognition and Sociality, Life Science Institute, Institute for Basic Science, Daejeon, South Korea
| | - Euisun Lee
- Center for Cognition and Sociality, Life Science Institute, Institute for Basic Science, Daejeon, South Korea
| | - Wuhyun Koh
- Center for Cognition and Sociality, Life Science Institute, Institute for Basic Science, Daejeon, South Korea.
| | - C Justin Lee
- Center for Cognition and Sociality, Life Science Institute, Institute for Basic Science, Daejeon, South Korea.
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3
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Supplisson S. Dynamic role of GlyT1 as glycine sink or source: Pharmacological implications for the gain control of NMDA receptors. Neuroscience 2024:S0306-4522(24)00350-6. [PMID: 39059742 DOI: 10.1016/j.neuroscience.2024.07.037] [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: 02/27/2024] [Revised: 07/03/2024] [Accepted: 07/22/2024] [Indexed: 07/28/2024]
Abstract
Glycine transporter 1 (GlyT1) mediates the termination of inhibitory glycinergic receptor signaling in the spinal cord and brainstem, and is also present diffusely in the forebrain. Here, it regulates the ambient glycine concentration and influences the 'glycine' site occupancy of N-methyl-d-aspartate receptors (NMDARs). GlyT1 is a reversible transporter with a substantial, but not excessive, sodium-motive force for uphill transport. This study investigates its role as a potential source of glycine supply, either by reverse uptake or heteroexchange. Indeed, glutamate alone does not induce NMDAR current in "naive" oocytes co-expressing GluN1/GluN2A and GlyT1, a previously characterized cellular model. However, after substantial intracellular glycine accumulation, GlyT1 reverses its transport mode, and begins to release glycine into the external compartment, allowing NMDAR activation by glutamate alone. These uptake-dependent glutamate currents were blocked by ALX-5407 and potentiated by sarcosine, a specific inhibitor and substrate of GlyT1, respectively, suggesting a higher occupancy of the co-agonist site when GlyT1 functions as a glycine source either by reversed-uptake or by heteroexchange. These two glycine release mechanisms can be distinguished by their voltage dependence, as the reversed-uptake cycle decreases at hyperpolarized potentials, whereas heteroexchange electroneutrality preserves glycine efflux and NMDAR activation at these potentials. These results establish GlyT1-mediated efflux as a positive regulator of NMDAR coagonist site occupancy, and demonstrate the efficacy of sarcosine heteroexchange in enhancing coagonist site occupancy. Because NMDAR facilitation by GlyT1-inhibitors and sarcosine relies on different transport mechanisms, their actions may be a source of variability in reversing NMDAR hypofunction in schizophrenia.
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Affiliation(s)
- Stéphane Supplisson
- Institut de Biologie de l'ENS (IBENS), Ecole normale supérieure, Université PSL, CNRS, INSERM, Paris, F-75005, France.
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4
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Biswas DD, Shi Y, El Haddad L, Sethi R, Huston M, Kehoe S, Scarrow ER, Strickland LM, Pucci LA, Dhindsa JS, Hunanyan A, La Spada AR, ElMallah MK. Respiratory neuropathology in spinocerebellar ataxia type 7. JCI Insight 2024; 9:e170444. [PMID: 39053472 PMCID: PMC11457860 DOI: 10.1172/jci.insight.170444] [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: 03/20/2023] [Accepted: 07/12/2024] [Indexed: 07/27/2024] Open
Abstract
Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurological disorder caused by deleterious CAG repeat expansion in the coding region of the ataxin 7 gene (polyQ-ataxin-7). Infantile-onset SCA7 leads to severe clinical manifestation of respiratory distress, but the exact cause of respiratory impairment remains unclear. Using the infantile-SCA7 mouse model, the SCA7266Q/5Q mouse, we examined the impact of pathological polyQ-ataxin-7 on hypoglossal (XII) and phrenic motor units. We identified the transcript profile of the medulla and cervical spinal cord and investigated the XII and phrenic nerves and the neuromuscular junctions in the diaphragm and tongue. SCA7266Q/5Q astrocytes showed significant intranuclear inclusions of ataxin-7 in the XII and putative phrenic motor nuclei. Transcriptomic analysis revealed dysregulation of genes involved in amino acid and neurotransmitter transport and myelination. Additionally, SCA7266Q/5Q mice demonstrated blunted efferent output of the XII nerve and demyelination in both XII and phrenic nerves. Finally, there was an increased number of neuromuscular junction clusters with higher expression of synaptic markers in SCA7266Q/5Q mice compared with WT controls. These preclinical findings elucidate the underlying pathophysiology responsible for impaired glial cell function and death leading to dysphagia, aspiration, and respiratory failure in infantile SCA7.
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Affiliation(s)
- Debolina D Biswas
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Yihan Shi
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Léa El Haddad
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Ronit Sethi
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Meredith Huston
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Sean Kehoe
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Evelyn R Scarrow
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Laura M Strickland
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Logan A Pucci
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Justin S Dhindsa
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Ani Hunanyan
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Albert R La Spada
- Departments of Pathology and Laboratory Medicine, Neurology, Biological Chemistry, and Neurobiology and Behavior, and
- UCI Center for Neurotherapeutics, University of California Irvine, Irvine, California, USA
| | - Mai K ElMallah
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
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Iwasaki R, Kohro Y, Tsuda M. A method for selective and efficient isolation of gray matter astrocytes from the spinal cord of adult mice. Mol Brain 2024; 17:25. [PMID: 38773624 PMCID: PMC11106874 DOI: 10.1186/s13041-024-01097-3] [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: 03/04/2024] [Accepted: 05/08/2024] [Indexed: 05/24/2024] Open
Abstract
A growing body of evidence indicates intra- and inter-regional heterogeneity of astrocytes in the brain. However, because of a lack of an efficient method for isolating astrocytes from the spinal cord, little is known about how much spinal cord astrocytes are heterogeneous in adult mice. In this study, we developed a new method for isolating spinal astrocytes from adult mice using a cold-active protease from Bacillus licheniformis with an astrocyte cell surface antigen-2 (ACSA-2) antibody. Using fluorescence-activated cell sorting, isolated spinal ACSA-2+ cells were divided into two distinct populations, ACSA-2high and ACSA-2low. By analyzing the expression of cell-type marker genes, the ACSA-2high and ACSA-2low populations were identified as astrocytes and ependymal cells, respectively. Furthermore, ACSA-2high cells had mRNAs encoding genes that were abundantly expressed in the gray matter (GM) but not white matter astrocytes. By optimizing enzymatic isolation procedures, the yield of GM astrocytes also increased. Therefore, our newly established method enabled the selective and efficient isolation of GM astrocytes from the spinal cord of adult mice and may be useful for bulk- or single-cell RNA-sequencing under physiological and pathological conditions.
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Affiliation(s)
- Ryoma Iwasaki
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Yuta Kohro
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Makoto Tsuda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
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6
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Li Y, Guo Y, Bröer A, Dai L, Brӧer S, Yan R. Cryo-EM structure of the human Asc-1 transporter complex. Nat Commun 2024; 15:3036. [PMID: 38589439 PMCID: PMC11001984 DOI: 10.1038/s41467-024-47468-1] [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: 10/10/2023] [Accepted: 04/02/2024] [Indexed: 04/10/2024] Open
Abstract
The Alanine-Serine-Cysteine transporter 1 (Asc-1 or SLC7A10) forms a crucial heterodimeric transporter complex with 4F2hc (SLC3A2) through a covalent disulfide bridge. This complex enables the sodium-independent transport of small neutral amino acids, including L-Alanine (L-Ala), Glycine (Gly), and D-Serine (D-Ser), within the central nervous system (CNS). D-Ser and Gly are two key endogenous glutamate co-agonists that activate N-methyl-d-aspartate (NMDA) receptors by binding to the allosteric site. Mice deficient in Asc-1 display severe symptoms such as tremors, ataxia, and seizures, leading to early postnatal death. Despite its physiological importance, the functional mechanism of the Asc-1-4F2hc complex has remained elusive. Here, we present cryo-electron microscopy (cryo-EM) structures of the human Asc-1-4F2hc complex in its apo state, D-Ser bound state, and L-Ala bound state, resolved at 3.6 Å, 3.5 Å, and 3.4 Å, respectively. Through detailed structural analysis and transport assays, we uncover a comprehensive alternating access mechanism that underlies conformational changes in the complex. In summary, our findings reveal the architecture of the Asc-1 and 4F2hc complex and provide valuable insights into substrate recognition and the functional cycle of this essential transporter complex.
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Affiliation(s)
- Yaning Li
- Department of Biochemistry, Key University Laboratory of Metabolism and Health of Guangdong, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yingying Guo
- Department of Biochemistry, Key University Laboratory of Metabolism and Health of Guangdong, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Angelika Bröer
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Lu Dai
- Department of Biochemistry, Key University Laboratory of Metabolism and Health of Guangdong, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Stefan Brӧer
- Research School of Biology, Australian National University, Canberra, ACT, Australia.
| | - Renhong Yan
- Department of Biochemistry, Key University Laboratory of Metabolism and Health of Guangdong, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong Province, China.
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Schaefer N, Harvey RJ, Villmann C. Startle Disease: New Molecular Insights into an Old Neurological Disorder. Neuroscientist 2023; 29:767-781. [PMID: 35754344 PMCID: PMC10623600 DOI: 10.1177/10738584221104724] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Startle disease (SD) is characterized by enhanced startle responses, generalized muscle stiffness, unexpected falling, and fatal apnea episodes due to disturbed feedback inhibition in the spinal cord and brainstem of affected individuals. Mutations within the glycine receptor (GlyR) subunit and glycine transporter 2 (GlyT2) genes have been identified in individuals with SD. Impaired inhibitory neurotransmission in SD is due to pre- and/or postsynaptic GlyR or presynaptic GlyT2 dysfunctions. Previous research has focused on mutated GlyRs and GlyT2 that impair ion channel/transporter function or trafficking. With insights provided by recently solved cryo-electron microscopy and X-ray structures of GlyRs, a detailed picture of structural transitions important for receptor gating has emerged, allowing a deeper understanding of SD at the molecular level. Moreover, studies on novel SD mutations have demonstrated a higher complexity of SD, with identification of additional clinical signs and symptoms and interaction partners representing key players for fine-tuning synaptic processes. Although our knowledge has steadily improved during the last years, changes in synaptic localization and GlyR or GlyT2 homeostasis under disease conditions are not yet completely understood. Combined proteomics, interactomics, and high-resolution microscopy techniques are required to reveal alterations in receptor dynamics at the synaptic level under disease conditions.
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Affiliation(s)
- Natascha Schaefer
- Institute of Clinical Neurobiology, University Hospital, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Robert J. Harvey
- School of Health and Behavioural Sciences, University of the Sunshine Coast, Maroochydore DC, Australia
- Sunshine Coast Health Institute, Birtinya, Australia
| | - Carmen Villmann
- Institute of Clinical Neurobiology, University Hospital, Julius-Maximilians-University of Würzburg, Würzburg, Germany
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8
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Drehmann P, Milanos S, Schaefer N, Kasaragod VB, Herterich S, Holzbach-Eberle U, Harvey RJ, Villmann C. Dual Role of Dysfunctional Asc-1 Transporter in Distinct Human Pathologies, Human Startle Disease, and Developmental Delay. eNeuro 2023; 10:ENEURO.0263-23.2023. [PMID: 37903619 PMCID: PMC10668224 DOI: 10.1523/eneuro.0263-23.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/11/2023] [Indexed: 11/01/2023] Open
Abstract
Human startle disease is associated with mutations in distinct genes encoding glycine receptors, transporters or interacting proteins at glycinergic synapses in spinal cord and brainstem. However, a significant number of diagnosed patients does not carry a mutation in the common genes GLRA1, GLRB, and SLC6A5 Recently, studies on solute carrier 7 subfamily 10 (SLC7A10; Asc-1, alanine-serine-cysteine transporter) knock-out (KO) mice displaying a startle disease-like phenotype hypothesized that this transporter might represent a novel candidate for human startle disease. Here, we screened 51 patients from our patient cohort negative for the common genes and found three exonic (one missense, two synonymous), seven intronic, and single nucleotide changes in the 5' and 3' untranslated regions (UTRs) in Asc-1. The identified missense mutation Asc-1G307R from a patient with startle disease and developmental delay was investigated in functional studies. At the molecular level, the mutation Asc-1G307R did not interfere with cell-surface expression, but disrupted glycine uptake. Substitution of glycine at position 307 to other amino acids, e.g., to alanine or tryptophan did not affect trafficking or glycine transport. By contrast, G307K disrupted glycine transport similar to the G307R mutation found in the patient. Structurally, the disrupted function in variants carrying positively charged residues can be explained by local structural rearrangements because of the large positively charged side chain. Thus, our data suggest that SLC7A10 may represent a rare but novel gene associated with human startle disease and developmental delay.
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Affiliation(s)
- Paul Drehmann
- Institute for Clinical Neurobiology, Julius Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Sinem Milanos
- Institute for Clinical Neurobiology, Julius Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Natascha Schaefer
- Institute for Clinical Neurobiology, Julius Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Vikram Babu Kasaragod
- Neurobiology Division, Medical Reserach Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Sarah Herterich
- Institute for Clinical Neurobiology, Julius Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Ulrike Holzbach-Eberle
- Center for Pediatrics and Adolescent Medicine, Pediatric Neurology, Social Pediatrics and Epileptology, University Hospital Gießen, 35392 Giessen, Germany
| | - Robert J Harvey
- School of Health, University of the Sunshine Coast, Sippy Downs, QLD 4558, Australia
- Sunshine Coast Health Institute, Birtinya, QLD 4575, Australia
| | - Carmen Villmann
- Institute for Clinical Neurobiology, Julius Maximilians University of Würzburg, 97078 Würzburg, Germany
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Krishnan KS, Billups B. ASC Transporters Mediate D-Serine Transport into Astrocytes Adjacent to Synapses in the Mouse Brain. Biomolecules 2023; 13:biom13050819. [PMID: 37238689 DOI: 10.3390/biom13050819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
D-serine is an important signalling molecule, which activates N-methyl D-aspartate receptors (NMDARs) in conjunction with its fellow co-agonist, the neurotransmitter glutamate. Despite its involvement in plasticity and memory related to excitatory synapses, its cellular source and sink remain a question. We hypothesise that astrocytes, a type of glial cell that surrounds synapses, are likely candidates to control the extracellular concentration of D-Serine by removing it from the synaptic space. Using in situ patch clamp recordings and pharmacological manipulation of astrocytes in the CA1 region of the mouse hippocampal brain slices, we investigated the transport of D-serine across the plasma membrane. We observed the D-serine-induced transport-associated currents upon puff-application of 10 mM D-serine on astrocytes. Further, O-benzyl-L-serine and trans-4-hydroxy-proline, known substrate inhibitors of the alanine serine cysteine transporters (ASCT), reduced D-serine uptake. These results indicate that ASCT is a central mediator of astrocytic D-serine transport and plays a role in regulating its synaptic concentration by sequestration into astrocytes. Similar results were observed in astrocytes of the somatosensory cortex and Bergmann glia in the cerebellum, indicative of a general mechanism expressed across a range of brain areas. This removal of synaptic D-serine and its subsequent metabolic degradation are expected to reduce its extracellular availability, influencing NMDAR activation and NMDAR-dependent synaptic plasticity.
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Affiliation(s)
- Karthik Subramanian Krishnan
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, 131 Garran Road, Canberra, ACT 2601, Australia
| | - Brian Billups
- Eccles Institute of Neuroscience, The John Curtin School of Medical Research, The Australian National University, 131 Garran Road, Canberra, ACT 2601, Australia
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Fogarty MJ. Inhibitory Synaptic Influences on Developmental Motor Disorders. Int J Mol Sci 2023; 24:ijms24086962. [PMID: 37108127 PMCID: PMC10138861 DOI: 10.3390/ijms24086962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
During development, GABA and glycine play major trophic and synaptic roles in the establishment of the neuromotor system. In this review, we summarise the formation, function and maturation of GABAergic and glycinergic synapses within neuromotor circuits during development. We take special care to discuss the differences in limb and respiratory neuromotor control. We then investigate the influences that GABAergic and glycinergic neurotransmission has on two major developmental neuromotor disorders: Rett syndrome and spastic cerebral palsy. We present these two syndromes in order to contrast the approaches to disease mechanism and therapy. While both conditions have motor dysfunctions at their core, one condition Rett syndrome, despite having myriad symptoms, has scientists focused on the breathing abnormalities and their alleviation-to great clinical advances. By contrast, cerebral palsy remains a scientific quagmire or poor definitions, no widely adopted model and a lack of therapeutic focus. We conclude that the sheer abundance of diversity of inhibitory neurotransmitter targets should provide hope for intractable conditions, particularly those that exhibit broad spectra of dysfunction-such as spastic cerebral palsy and Rett syndrome.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55902, USA
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11
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Piniella D, Zafra F. Functional crosstalk of the glycine transporter GlyT1 and NMDA receptors. Neuropharmacology 2023; 232:109514. [PMID: 37003571 DOI: 10.1016/j.neuropharm.2023.109514] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/10/2023] [Accepted: 03/20/2023] [Indexed: 04/03/2023]
Abstract
NMDA-type glutamate receptors (NMDARs) constitute one of the main glutamate (Glu) targets in the central nervous system and are involved in synaptic plasticity, which is the molecular substrate of learning and memory. Hypofunction of NMDARs has been associated with schizophrenia, while overstimulation causes neuronal death in neurodegenerative diseases or in stroke. The function of NMDARs requires coincidental binding of Glu along with other cellular signals such as neuronal depolarization, and the presence of other endogenous ligands that modulate their activity by allosterism. Among these allosteric modulators are zinc, protons and Gly, which is an obligatory co-agonist. These characteristics differentiate NMDARs from other receptors, and their structural bases have begun to be established in recent years. In this review we focus on the crosstalk between Glu and glycine (Gly), whose concentration in the NMDAR microenvironment is maintained by various Gly transporters that remove or release it into the medium in a regulated manner. The GlyT1 transporter is particularly involved in this task, and has become a target of great interest for the treatment of schizophrenia since its inhibition leads to an increase in synaptic Gly levels that enhances the activity of NMDARs. However, the only drug that has completed phase III clinical trials did not yield the expected results. Notwithstanding, there are additional drugs that continue to be investigated, and it is hoped that knowledge gained from the recently published 3D structure of GlyT1 may allow the rational design of more effective new drugs.
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Affiliation(s)
- Dolores Piniella
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain; IdiPAZ, Institute of Health Carlos III (ISCIII), Spain
| | - Francisco Zafra
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain; IdiPAZ, Institute of Health Carlos III (ISCIII), Spain.
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12
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Kong W, Montano M, Corley MJ, Helmy E, Kobayashi H, Kinisu M, Suryawanshi R, Luo X, Royer LA, Roan NR, Ott M, Ndhlovu LC, Greene WC. Neuropilin-1 Mediates SARS-CoV-2 Infection of Astrocytes in Brain Organoids, Inducing Inflammation Leading to Dysfunction and Death of Neurons. mBio 2022; 13:e0230822. [PMID: 36314791 PMCID: PMC9765283 DOI: 10.1128/mbio.02308-22] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/05/2022] [Indexed: 11/07/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is frequently associated with neurological deficits, but how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces these effects remains unclear. Here, we show that astrocytes are readily infected by SARS-CoV-2, but surprisingly, neuropilin-1, not angiotensin-converting enzyme 2 (ACE2), serves as the principal receptor mediating cell entry. Infection is further positively modulated by the two-pore segment channel 2 (TPC2) protein that regulates membrane trafficking and endocytosis. Astrocyte infection produces a pathological response closely resembling reactive astrogliosis characterized by elevated type I interferon (IFN) production, increased inflammation, and the decreased expression of transporters of water, ions, choline, and neurotransmitters. These combined events initiated within astrocytes produce a hostile microenvironment that promotes the dysfunction and death of uninfected bystander neurons. IMPORTANCE SARS-CoV-2 infection primarily targets the lung but may also damage other organs, including the brain, heart, kidney, and intestine. Central nervous system (CNS) pathologies include loss of smell and taste, headache, delirium, acute psychosis, seizures, and stroke. Pathological loss of gray matter occurs in SARS-CoV-2 infection, but it is unclear whether this is due to direct viral infection, indirect effects associated with systemic inflammation, or both. Here, we used induced pluripotent stem cell (iPSC)-derived brain organoids and primary human astrocytes from the cerebral cortex to study direct SARS-CoV-2 infection. Our findings support a model where SARS-CoV-2 infection of astrocytes produces a panoply of changes in the expression of genes regulating innate immune signaling and inflammatory responses. The deregulation of these genes in astrocytes produces a microenvironment within the CNS that ultimately disrupts normal neuron function, promoting neuronal cell death and CNS deficits.
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Affiliation(s)
- Weili Kong
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
| | - Mauricio Montano
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
| | - Michael J. Corley
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Ekram Helmy
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
| | | | - Martin Kinisu
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
| | | | - Xiaoyu Luo
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
| | | | - Nadia R. Roan
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Melanie Ott
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, San Francisco, California, USA
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, USA
| | - Lishomwa C. Ndhlovu
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Warner C. Greene
- Michael Hulton Center for HIV Cure Research at Gladstone, San Francisco, California, USA
- Gladstone Institute of Virology, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, San Francisco, California, USA
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, USA
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13
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Álvarez-Merz I, Fomitcheva IV, Sword J, Hernández-Guijo JM, Solís JM, Kirov SA. Novel mechanism of hypoxic neuronal injury mediated by non-excitatory amino acids and astroglial swelling. Glia 2022; 70:2108-2130. [PMID: 35802030 PMCID: PMC9474671 DOI: 10.1002/glia.24241] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/14/2022] [Accepted: 06/24/2022] [Indexed: 11/08/2022]
Abstract
In ischemic stroke and post-traumatic brain injury (TBI), blood-brain barrier disruption leads to leaking plasma amino acids (AA) into cerebral parenchyma. Bleeding in hemorrhagic stroke and TBI also release plasma AA. Although excitotoxic AA were extensively studied, little is known about non-excitatory AA during hypoxic injury. Hypoxia-induced synaptic depression in hippocampal slices becomes irreversible with non-excitatory AA, alongside their intracellular accumulation and increased tissue electrical resistance. Four non-excitatory AA (l-alanine, glycine, l-glutamine, l-serine: AGQS) at plasmatic concentrations were applied to slices from mice expressing EGFP in pyramidal neurons or astrocytes during normoxia or hypoxia. Two-photon imaging, light transmittance (LT) changes, and electrophysiological field recordings followed by electron microscopy in hippocampal CA1 st. radiatum were used to monitor synaptic function concurrently with cellular swelling and injury. During normoxia, AGQS-induced increase in LT was due to astroglial but not neuronal swelling. LT raise during hypoxia and AGQS manifested astroglial and neuronal swelling accompanied by a permanent loss of synaptic transmission and irreversible dendritic beading, signifying acute damage. Neuronal injury was not triggered by spreading depolarization which did not occur in our experiments. Hypoxia without AGQS did not cause cell swelling, leaving dendrites intact. Inhibition of NMDA receptors prevented neuronal damage and irreversible loss of synaptic function. Deleterious effects of AGQS during hypoxia were prevented by alanine-serine-cysteine transporters (ASCT2) and volume-regulated anion channels (VRAC) blockers. Our findings suggest that astroglial swelling induced by accumulation of non-excitatory AA and release of excitotoxins through antiporters and VRAC may exacerbate the hypoxia-induced neuronal injury.
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Affiliation(s)
- Iris Álvarez-Merz
- Dept. de Farmacología y Terapéutica, ITH, Facultad de Medicina, Universidad Autónoma de Madrid, IRYCIS, 28029 Madrid, Spain
- Servicio de Neurobiología-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, 28034 Madrid, Spain
- Dept. of Neuroscience and Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia 30912, USA
| | - Ioulia V. Fomitcheva
- Dept. of Neurosurgery, Medical College of Georgia at Augusta University, Augusta, Georgia 30912, USA
| | - Jeremy Sword
- Dept. of Neuroscience and Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia 30912, USA
| | - Jesús M. Hernández-Guijo
- Dept. de Farmacología y Terapéutica, ITH, Facultad de Medicina, Universidad Autónoma de Madrid, IRYCIS, 28029 Madrid, Spain
| | - José M. Solís
- Servicio de Neurobiología-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, 28034 Madrid, Spain
| | - Sergei A. Kirov
- Dept. of Neuroscience and Regenerative Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia 30912, USA
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14
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Tapanes SA, Arizanovska D, Díaz MM, Folorunso OO, Harvey T, Brown SE, Radzishevsky I, Close LN, Jagid JR, Graciolli Cordeiro J, Wolosker H, Balu DT, Liebl DJ. Inhibition of glial D-serine release rescues synaptic damage after brain injury. Glia 2022; 70:1133-1152. [PMID: 35195906 PMCID: PMC9305835 DOI: 10.1002/glia.24161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/13/2022] [Accepted: 02/04/2022] [Indexed: 11/28/2022]
Abstract
Synaptic damage is one of the most prevalent pathophysiological responses to traumatic CNS injury and underlies much of the associated cognitive dysfunction; however, it is poorly understood. The D-amino acid, D-serine, serves as the primary co-agonist at synaptic NMDA receptors (NDMARs) and is a critical mediator of NMDAR-dependent transmission and synaptic plasticity. In physiological conditions, D-serine is produced and released by neurons from the enzymatic conversion of L-serine by serine racemase (SRR). However, under inflammatory conditions, glial cells become a major source of D-serine. Here, we report that D-serine synthesized by reactive glia plays a critical role in synaptic damage after traumatic brain injury (TBI) and identify the therapeutic potential of inhibiting glial D-serine release though the transporter Slc1a4 (ASCT1). Furthermore, using cell-specific genetic strategies and pharmacology, we demonstrate that TBI-induced synaptic damage and memory impairment requires D-serine synthesis and release from both reactive astrocytes and microglia. Analysis of the murine cortex and acutely resected human TBI brain also show increased SRR and Slc1a4 levels. Together, these findings support a novel role for glial D-serine in acute pathological dysfunction following brain trauma, whereby these reactive cells provide the excess co-agonist levels necessary to initiate NMDAR-mediated synaptic damage.
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Affiliation(s)
- Stephen A. Tapanes
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Dena Arizanovska
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Madelen M. Díaz
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Oluwarotimi O. Folorunso
- Department of PsychiatryHarvard Medical SchoolBostonMassachusettsUSA
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Theresa Harvey
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Stephanie E. Brown
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Inna Radzishevsky
- Department of Biochemistry, Rappaport Faculty of MedicineTechnion‐Israel Institute of TechnologyHaifaIsrael
| | - Liesl N. Close
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Jonathan R. Jagid
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Joacir Graciolli Cordeiro
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Herman Wolosker
- Department of Biochemistry, Rappaport Faculty of MedicineTechnion‐Israel Institute of TechnologyHaifaIsrael
| | - Darrick T. Balu
- Department of PsychiatryHarvard Medical SchoolBostonMassachusettsUSA
- Translational Psychiatry LaboratoryMcLean HospitalBelmontMassachusettsUSA
| | - Daniel J. Liebl
- The Miami Project to Cure Paralysis, Department of Neurological SurgeryUniversity of Miami Miller School of MedicineMiamiFloridaUSA
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15
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Eulenburg V, Hülsmann S. Synergistic Control of Transmitter Turnover at Glycinergic Synapses by GlyT1, GlyT2, and ASC-1. Int J Mol Sci 2022; 23:ijms23052561. [PMID: 35269698 PMCID: PMC8909939 DOI: 10.3390/ijms23052561] [Citation(s) in RCA: 12] [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: 02/04/2022] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 01/25/2023] Open
Abstract
In addition to being involved in protein biosynthesis and metabolism, the amino acid glycine is the most important inhibitory neurotransmitter in caudal regions of the brain. These functions require a tight regulation of glycine concentration not only in the synaptic cleft, but also in various intracellular and extracellular compartments. This is achieved not only by confining the synthesis and degradation of glycine predominantly to the mitochondria, but also by the action of high-affinity large-capacity glycine transporters that mediate the transport of glycine across the membranes of presynaptic terminals or glial cells surrounding the synapses. Although most cells at glycine-dependent synapses express more than one transporter with high affinity for glycine, their synergistic functional interaction is only poorly understood. In this review, we summarize our current knowledge of the two high-affinity transporters for glycine, the sodium-dependent glycine transporters 1 (GlyT1; SLC6A9) and 2 (GlyT2; SLC6A5) and the alanine–serine–cysteine-1 transporter (Asc-1; SLC7A10).
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Affiliation(s)
- Volker Eulenburg
- Department for Anesthesiology and Intensive Care, Faculty of Medicine, University of Leipzig, Liebigstraße 20, D-04103 Leipzig, Germany
- Correspondence: (V.E.); (S.H.)
| | - Swen Hülsmann
- Department for Anesthesiology, University Medical Center, Georg-August University, Humboldtallee 23, D-37073 Göttingen, Germany
- Correspondence: (V.E.); (S.H.)
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16
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Tatsumi K, Kinugawa K, Isonishi A, Kitabatake M, Okuda H, Takemura S, Tanaka T, Mori E, Wanaka A. Olig2-astrocytes express neutral amino acid transporter SLC7A10 (Asc-1) in the adult brain. Mol Brain 2021; 14:163. [PMID: 34749773 PMCID: PMC8573876 DOI: 10.1186/s13041-021-00874-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 10/28/2021] [Indexed: 11/23/2022] Open
Abstract
We have reported that the transcription factor Olig2 labels a subpopulation of astrocytes (Olig2-astrocytes), which show distribution patterns different from those of GFAP-expressing astrocytes (GFAP-astrocytes) in the adult brain. Here, to uncover the specific functions of Olig2-astrocytes, we first analyzed public single-cell RNA-seq databases of adult mouse brains. Unbiased classification of gene expression profiles and subsequent gene ontology analyses revealed that the majority of Olig2-astrocytes belonged to an astrocytic cluster that is enriched for transporter-related genes. SLC7A10 (also known as ASC-1) was one of the representative neutral amino acid transporter genes in the cluster. To complement the in silico data analyses, we differentially isolated Olig2- and GFAP-astrocytes from the same frozen section of the lateral globus pallidus using laser microdissection and compared their gene expression by quantitative reverse transcription PCR. We confirmed that Olig2 and GFAP mRNAs were preferentially expressed in the Olig2- and GFAP-astrocytes, respectively, indicating that the laser microdissection method yielded minimal cross-contamination between two types of cells. The Olig2-astrocytes expressed significantly higher levels of SLC7A10 mRNA than the GFAP-astrocytes, corroborating the in silico data. We next localized SLC7A10 protein by immunohistochemistry in the lateral globus pallidus, which was also genetically labeled for Olig2. SLC7A10 co-localized with Olig2-genetic labeling, especially on the fine processes of Olig2-astrocytes. These results are consistent with the recent discovery that SLC7A10 is expressed not only in neurons but also in a subset of astrocytes. Taken together, our findings suggest that SLC7A10 exerts specific functions in Olig2-astrocytes of the adult brain.
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Affiliation(s)
- Kouko Tatsumi
- Department of Anatomy and Neuroscience, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan.
| | - Kaoru Kinugawa
- Department of Neurology, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Ayami Isonishi
- Department of Anatomy and Neuroscience, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Masahiro Kitabatake
- Department of Immunology, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Hiroaki Okuda
- Department of Anatomy, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, 920-1192, Japan
| | - Shoko Takemura
- Department of Anatomy and Neuroscience, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Tatsuhide Tanaka
- Department of Anatomy and Neuroscience, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Eiichiro Mori
- Department of Future Basic Medicine, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
| | - Akio Wanaka
- Department of Anatomy and Neuroscience, Faculty of Medicine, Nara Medical University, Kashihara, Nara, 634-8521, Japan
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17
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Zhan FX, Wang SG, Cao L. Advances in hyperekplexia and other startle syndromes. Neurol Sci 2021; 42:4095-4107. [PMID: 34379238 DOI: 10.1007/s10072-021-05493-8] [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: 05/13/2021] [Accepted: 07/14/2021] [Indexed: 02/03/2023]
Abstract
Startle, a basic alerting reaction common to all mammals, is described as a sudden involuntary movement of the body evoked by all kinds of sudden and unexpected stimulus. Startle syndromes are heterogeneous groups of disorders with abnormal and exaggerated responses to startling events, including hyperekplexia, stimulus-induced disorders, and neuropsychiatric startle syndromes. Hyperekplexia can be attributed to a genetic, idiopathic, or symptomatic cause. Excluding secondary factors, hereditary hyperekplexia, a rare neurogenetic disorder with highly genetic heterogeneity, is characterized by neonatal hypertonia, exaggerated startle response provoked by the sudden external stimuli, and followed by a short period of general stiffness. It mainly arises from defects of inhibitory glycinergic neurotransmission. GLRA1 is the major pathogenic gene of hereditary hyperekplexia, along with many other genes involved in the function of glycinergic inhibitory synapses. While about 40% of patients remain negative genetic findings. Clonazepam, which can specifically upgrade the GABARA1 chloride channels, is the main and most effective administration for hereditary hyperekplexia patients. In this review, with the aim at enhancing the recognition and prompting potential treatment for hyperekplexia, we focused on discussing the advances in hereditary hyperekplexia genetics and the expound progress in pathogenic mechanisms of the glycinergic-synapse-related pathway and then followed by a brief overview of other common startle syndromes.
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Affiliation(s)
- Fei-Xia Zhan
- Department of Neurology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai, 200233, China
| | - Shi-Ge Wang
- Department of Neurology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai, 200233, China
| | - Li Cao
- Department of Neurology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai, 200233, China.
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18
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Yair S, Lee KM, Coop G. The timing of human adaptation from Neanderthal introgression. Genetics 2021; 218:iyab052. [PMID: 33787889 PMCID: PMC8128397 DOI: 10.1093/genetics/iyab052] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 02/26/2021] [Indexed: 12/26/2022] Open
Abstract
Admixture has the potential to facilitate adaptation by providing alleles that are immediately adaptive in a new environment or by simply increasing the long-term reservoir of genetic diversity for future adaptation. A growing number of cases of adaptive introgression are being identified in species across the tree of life, however the timing of selection, and therefore the importance of the different evolutionary roles of admixture, is typically unknown. Here, we investigate the spatio-temporal history of selection favoring Neanderthal-introgressed alleles in modern human populations. Using both ancient and present-day samples of modern humans, we integrate the known demographic history of populations, namely population divergence and migration, with tests for selection. We model how a sweep placed along different branches of an admixture graph acts to modify the variance and covariance in neutral allele frequencies among populations at linked loci. Using a method based on this model of allele frequencies, we study previously identified cases of adaptive Neanderthal introgression. From these, we identify cases in which Neanderthal-introgressed alleles were quickly beneficial and other cases in which they persisted at low frequency for some time. For some of the alleles that persisted at low frequency, we show that selection likely independently favored them later on in geographically separated populations. Our work highlights how admixture with ancient hominins has contributed to modern human adaptation and contextualizes observed levels of Neanderthal ancestry in present-day and ancient samples.
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Affiliation(s)
- Sivan Yair
- Center for Population Biology, University of California, Davis, Davis, CA 95616, USA
- Department of Evolution and Ecology, University of California, Davis, Davis, CA 95616, USA
| | - Kristin M Lee
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Graham Coop
- Center for Population Biology, University of California, Davis, Davis, CA 95616, USA
- Department of Evolution and Ecology, University of California, Davis, Davis, CA 95616, USA
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19
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Brill SE, Maraslioglu A, Kurz C, Kramer F, Fuhr MF, Singh A, Friauf E. Glycinergic Transmission in the Presence and Absence of Functional GlyT2: Lessons From the Auditory Brainstem. Front Synaptic Neurosci 2021; 12:560008. [PMID: 33633558 PMCID: PMC7900164 DOI: 10.3389/fnsyn.2020.560008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 12/01/2020] [Indexed: 12/20/2022] Open
Abstract
Synaptic transmission is controlled by re-uptake systems that reduce transmitter concentrations in the synaptic cleft and recycle the transmitter into presynaptic terminals. The re-uptake systems are thought to ensure cytosolic concentrations in the terminals that are sufficient for reloading empty synaptic vesicles (SVs). Genetic deletion of glycine transporter 2 (GlyT2) results in severely disrupted inhibitory neurotransmission and ultimately to death. Here we investigated the role of GlyT2 at inhibitory glycinergic synapses in the mammalian auditory brainstem. These synapses are tuned for resilience, reliability, and precision, even during sustained high-frequency stimulation when endocytosis and refilling of SVs probably contribute substantially to efficient replenishment of the readily releasable pool (RRP). Such robust synapses are formed between MNTB and LSO neurons (medial nucleus of the trapezoid body, lateral superior olive). By means of patch-clamp recordings, we assessed the synaptic performance in controls, in GlyT2 knockout mice (KOs), and upon acute pharmacological GlyT2 blockade. Via computational modeling, we calculated the reoccupation rate of empty release sites and RRP replenishment kinetics during 60-s challenge and 60-s recovery periods. Control MNTB-LSO inputs maintained high fidelity neurotransmission at 50 Hz for 60 s and recovered very efficiently from synaptic depression. During 'marathon-experiments' (30,600 stimuli in 20 min), RRP replenishment accumulated to 1,260-fold. In contrast, KO inputs featured severe impairments. For example, the input number was reduced to ~1 (vs. ~4 in controls), implying massive functional degeneration of the MNTB-LSO microcircuit and a role of GlyT2 during synapse maturation. Surprisingly, neurotransmission did not collapse completely in KOs as inputs still replenished their small RRP 80-fold upon 50 Hz | 60 s challenge. However, they totally failed to do so for extended periods. Upon acute pharmacological GlyT2 inactivation, synaptic performance remained robust, in stark contrast to KOs. RRP replenishment was 865-fold in marathon-experiments, only ~1/3 lower than in controls. Collectively, our empirical and modeling results demonstrate that GlyT2 re-uptake activity is not the dominant factor in the SV recycling pathway that imparts indefatigability to MNTB-LSO synapses. We postulate that additional glycine sources, possibly the antiporter Asc-1, contribute to RRP replenishment at these high-fidelity brainstem synapses.
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Affiliation(s)
- Sina E Brill
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Ayse Maraslioglu
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Catharina Kurz
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Florian Kramer
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Martin F Fuhr
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Abhyudai Singh
- Electrical & Computer Engineering, University of Delaware, Newark, DE, United States
| | - Eckhard Friauf
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
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20
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Asc-1 Transporter (SLC7A10): Homology Models And Molecular Dynamics Insights Into The First Steps Of The Transport Mechanism. Sci Rep 2020; 10:3731. [PMID: 32111919 PMCID: PMC7048771 DOI: 10.1038/s41598-020-60617-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 02/14/2020] [Indexed: 12/02/2022] Open
Abstract
The alanine-serine-cysteine transporter Asc-1 regulates the synaptic availability of d-serine and glycine (the two co-agonists of the NMDA receptor) and is regarded as an important drug target. To shuttle the substrate from the extracellular space to the cytoplasm, this transporter undergoes multiple distinct conformational states. In this work, homology modeling, substrate docking and molecular dynamics simulations were carried out to learn more about the transition between the “outward-open” and “outward-open occluded” states. We identified a transition state involving the highly-conserved unwound TM6 region in which the Phe243 flips close to the d-serine substrate without major movements of TM6. This feature and those of other key residues are proposed to control the binding site and substrate translocation. Competitive inhibitors ACPP, LuAE00527 and SMLC were docked and their binding modes at the substrate binding site corroborated the key role played by Phe243 of TM6. For ACPP and LuAE00527, strong hydrophobic interactions with this residue hinder its mobility and prevent the uptake and the efflux of substrates. As for SMLC, the weaker interactions maintain the flexibility of Phe243 and the efflux process. Overall, we propose a molecular basis for the inhibition of substrate translocation of the Asc-1 transporter that should be valuable for rational drug design.
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21
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Klemens J, Ciurkiewicz M, Chludzinski E, Iseringhausen M, Klotz D, Pfankuche VM, Ulrich R, Herder V, Puff C, Baumgärtner W, Beineke A. Neurotoxic potential of reactive astrocytes in canine distemper demyelinating leukoencephalitis. Sci Rep 2019; 9:11689. [PMID: 31406213 PMCID: PMC6690900 DOI: 10.1038/s41598-019-48146-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 07/25/2019] [Indexed: 12/20/2022] Open
Abstract
Canine distemper virus (CDV) causes a fatal demyelinating leukoencephalitis in young dogs resembling human multiple sclerosis. Astrocytes are the main cellular target of CDV and undergo reactive changes already in pre-demyelinating brain lesions. Based on their broad range of beneficial and detrimental effects in the injured brain reactive astrogliosis is in need of intensive investigation. The aim of the study was to characterize astrocyte plasticity during the course of CDV-induced demyelinating leukoencephalitis by the aid of immunohistochemistry, immunofluorescence and gene expression analysis. Immunohistochemistry revealed the presence of reactive glial fibrillary acidic protein (GFAP)+ astrocytes with increased survivin and reduced aquaporin 4, and glutamine synthetase protein levels, indicating disturbed blood brain barrier function, glutamate homeostasis and astrocyte maladaptation, respectively. Gene expression analysis revealed 81 differentially expressed astrocyte-related genes with a dominance of genes associated with neurotoxic A1-polarized astrocytes. Accordingly, acyl-coA synthetase long-chain family member 5+/GFAP+, and serglycin+/GFAP+ cells, characteristic of A1-astrocytes, were found in demyelinating lesions by immunofluorescence. In addition, gene expression revealed a dysregulation of astrocytic function including disturbed glutamate homeostasis and altered immune function. Observed findings indicate an astrocyte polarization towards a neurotoxic phenotype likely contributing to lesion initiation and progression in canine distemper leukoencephalitis.
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Affiliation(s)
- J Klemens
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
| | - M Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - E Chludzinski
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - M Iseringhausen
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
| | - D Klotz
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
| | - V M Pfankuche
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - R Ulrich
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Greifswald, Insel Riems, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - V Herder
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - C Puff
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
| | - W Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - A Beineke
- Department of Pathology, University of Veterinary Medicine Hanover, Hannover, Germany.
- Center for Systems Neuroscience, Hannover, Germany.
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22
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Hypothalamic and pituitary transcriptome profiling using RNA-sequencing in high-yielding and low-yielding laying hens. Sci Rep 2019; 9:10285. [PMID: 31311989 PMCID: PMC6635495 DOI: 10.1038/s41598-019-46807-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 07/05/2019] [Indexed: 12/21/2022] Open
Abstract
The reproductive physiology and laying performance of laying hens are regulated by the hypothalamus and pituitary. To understand the mechanism of egg laying regulation, we sequenced and analysed the hypothalamus and pituitary expression profiles in high- and low-yielding laying Chinese Dagu Chickens (CDC) using RNA-seq. More than 46 million clean reads and 24,873 tentative genes were obtained using the Gallus gallus genome as a reference. Transcriptome analysis in hypothalamus and pituitary revealed seven and 39 differentially expressed genes (DEGs) between high- and low-yielding CDC hens, respectively. A total of 24 and 22 DEGs were up-regulated and down-regulated, respectively, and 13 novel genes were identified. Functional annotation and pathway enrichment analysis showed that DEGs in the hypothalamus were mainly enriched in glycosaminoglycan biosynthesis. DEGs significantly enriched in the pituitary primarily affected the extracellular matrix, the protein extracellular matrix, and the extracellular space. Pathways involving phenylalanine metabolism, 2-oxocarboxylic acid metabolism, the glycosphingolipid biosynthesis-ganglion series, and local adhesion were significantly enriched in the pituitary. Eight DEGs, PRDX6, TRIB2, OVCH2, CFD, Peptidase M20, SLC7A10, and two other amino acid transporters, are involved in the metabolism and transport of amino acids. To our knowledge, this is the first study comparing the hypothalamus and pituitary transcriptomes of high- and low-yielding laying hens. Our findings suggest that putative differences in gene expression can provide a base for further research in this field. Moreover, we identified increased expression of genes involved in amino acid metabolism, glycosaminoglycan biosynthesis, and oestrogen negative feedback systems in low-yielding laying hens, highlighting their potential as biomarkers of egg production.
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23
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Bartoccioni P, Fort J, Zorzano A, Errasti-Murugarren E, Palacín M. Functional characterization of the alanine-serine-cysteine exchanger of Carnobacterium sp AT7. J Gen Physiol 2019; 151:505-517. [PMID: 30696726 PMCID: PMC6445583 DOI: 10.1085/jgp.201812195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/16/2018] [Accepted: 01/03/2019] [Indexed: 01/18/2023] Open
Abstract
Proteins of the L-type amino acid transporter (LAT) subfamily take up amino acids from the environment for use in the cell. Bartoccioni et al. show that the bacterial amino acid exchanger BasC is functionally similar to the human LAT Asc1, making BasC a useful model for this class of transporters. Many key cell processes require prior cell uptake of amino acids from the environment, which is facilitated by cell membrane amino acid transporters such as those of the L-type amino acid transporter (LAT) subfamily. Alterations in LAT subfamily amino acid transport are associated with several human diseases, including cancer, aminoacidurias, and neurodegenerative conditions. Therefore, from the perspective of human health, there is considerable interest in obtaining structural information about these transporter proteins. We recently solved the crystal structure of the first LAT transporter, the bacterial alanine-serine-cysteine exchanger of Carnobacterium sp AT7 (BasC). Here, we provide a complete functional characterization of detergent-purified, liposome-reconstituted BasC transporter to allow the extension of the structural insights into mechanistic understanding. BasC is a sodium- and proton-independent small neutral amino acid exchanger whose substrate and inhibitor selectivity are almost identical to those previously described for the human LAT subfamily member Asc-1. Additionally, we show that, like its human counterparts, this transporter has apparent affinity asymmetry for the intra- and extracellular substrate binding sites—a key feature in the physiological role played by these proteins. BasC is an excellent paradigm of human LAT transporters and will contribute to our understanding of the molecular mechanisms underlying substrate recognition and translocation at both sides of the plasma membrane.
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Affiliation(s)
- Paola Bartoccioni
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain
| | - Joana Fort
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain.,Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Antonio Zorzano
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
| | - Ekaitz Errasti-Murugarren
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Palacín
- Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, Barcelona, Spain .,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain.,Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain
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24
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Wang Q, Zuo Z. Impact of transporters and enzymes from blood–cerebrospinal fluid barrier and brain parenchyma on CNS drug uptake. Expert Opin Drug Metab Toxicol 2018; 14:961-972. [DOI: 10.1080/17425255.2018.1513493] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Qianwen Wang
- School of Pharmacy, The Chinese University of Hong Kong, Hong Kong, P. R. China
| | - Zhong Zuo
- School of Pharmacy, The Chinese University of Hong Kong, Hong Kong, P. R. China
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25
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Mesuret G, Khabbazzadeh S, Bischoff AM, Safory H, Wolosker H, Hülsmann S. A neuronal role of the Alanine-Serine-Cysteine-1 transporter (SLC7A10, Asc-1) for glycine inhibitory transmission and respiratory pattern. Sci Rep 2018; 8:8536. [PMID: 29867218 PMCID: PMC5986860 DOI: 10.1038/s41598-018-26868-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 05/16/2018] [Indexed: 12/31/2022] Open
Abstract
The Alanine-Serine-Cysteine-1 transporter (SLC7A10, Asc-1) has been shown to play a role in synaptic availability of glycine although the exact mechanism remains unclear. We used electrophysiological recordings and biochemical experiments to investigate the role of Asc-1 transporter in glycinergic transmission in the brainstem respiratory network. Using both the Asc-1 substrate and transportable inhibitor D-isoleucine (D-Ile), and the non-transportable Asc-1 blocker Lu AE00527 (Lu), we found that D-Ile reduces glycinergic transmission and increases glycine release via hetero-exchange, whereas Lu has no acute effect on glycinergic synaptic transmission. Furthermore, D-Ile increases the frequency and reduces amplitude of the phrenic nerve activity in the arterially-perfused working heart brainstem preparation. These results suggest a role of Asc-1 in modulating presynaptic glycine levels that can impact on the respiratory network.
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Affiliation(s)
- Guillaume Mesuret
- Clinic for Anesthesiology, University Medical Center, Göttingen, Germany.,Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | | | - Anne M Bischoff
- Clinic for Anesthesiology, University Medical Center, Göttingen, Germany
| | - Hazem Safory
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel
| | - Herman Wolosker
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel
| | - Swen Hülsmann
- Clinic for Anesthesiology, University Medical Center, Göttingen, Germany. .,Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
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26
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Rosenberg AB, Roco CM, Muscat RA, Kuchina A, Sample P, Yao Z, Graybuck LT, Peeler DJ, Mukherjee S, Chen W, Pun SH, Sellers DL, Tasic B, Seelig G. Single-cell profiling of the developing mouse brain and spinal cord with split-pool barcoding. Science 2018; 360:176-182. [PMID: 29545511 PMCID: PMC7643870 DOI: 10.1126/science.aam8999] [Citation(s) in RCA: 799] [Impact Index Per Article: 133.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 09/30/2017] [Accepted: 02/26/2018] [Indexed: 12/11/2022]
Abstract
To facilitate scalable profiling of single cells, we developed split-pool ligation-based transcriptome sequencing (SPLiT-seq), a single-cell RNA-seq (scRNA-seq) method that labels the cellular origin of RNA through combinatorial barcoding. SPLiT-seq is compatible with fixed cells or nuclei, allows efficient sample multiplexing, and requires no customized equipment. We used SPLiT-seq to analyze 156,049 single-nucleus transcriptomes from postnatal day 2 and 11 mouse brains and spinal cords. More than 100 cell types were identified, with gene expression patterns corresponding to cellular function, regional specificity, and stage of differentiation. Pseudotime analysis revealed transcriptional programs driving four developmental lineages, providing a snapshot of early postnatal development in the murine central nervous system. SPLiT-seq provides a path toward comprehensive single-cell transcriptomic analysis of other similarly complex multicellular systems.
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Affiliation(s)
| | - Charles M Roco
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Richard A Muscat
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Anna Kuchina
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Paul Sample
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, WA, USA
| | | | - David J Peeler
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Sumit Mukherjee
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Wei Chen
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, USA
| | - Suzie H Pun
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Drew L Sellers
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| | | | - Georg Seelig
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA.
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, USA
- Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, WA, USA
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27
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28
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Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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29
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Verkhratsky A, Nedergaard M. Physiology of Astroglia. Physiol Rev 2018; 98:239-389. [PMID: 29351512 PMCID: PMC6050349 DOI: 10.1152/physrev.00042.2016] [Citation(s) in RCA: 951] [Impact Index Per Article: 158.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/22/2017] [Accepted: 04/27/2017] [Indexed: 02/07/2023] Open
Abstract
Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
| | - Maiken Nedergaard
- The University of Manchester , Manchester , United Kingdom ; Achúcarro Basque Center for Neuroscience, IKERBASQUE, Basque Foundation for Science , Bilbao , Spain ; Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain ; Center for Basic and Translational Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark ; and Center for Translational Neuromedicine, University of Rochester Medical Center , Rochester, New York
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