1
|
Van Steenwinckel J, Bokobza C, Laforge M, Shearer IK, Miron VE, Rua R, Matta SM, Hill‐Yardin EL, Fleiss B, Gressens P. Key roles of glial cells in the encephalopathy of prematurity. Glia 2024; 72:475-503. [PMID: 37909340 PMCID: PMC10952406 DOI: 10.1002/glia.24474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/17/2023] [Accepted: 09/19/2023] [Indexed: 11/03/2023]
Abstract
Across the globe, approximately one in 10 babies are born preterm, that is, before 37 weeks of a typical 40 weeks of gestation. Up to 50% of preterm born infants develop brain injury, encephalopathy of prematurity (EoP), that substantially increases their risk for developing lifelong defects in motor skills and domains of learning, memory, emotional regulation, and cognition. We are still severely limited in our abilities to prevent or predict preterm birth. No longer just the "support cells," we now clearly understand that during development glia are key for building a healthy brain. Glial dysfunction is a hallmark of EoP, notably, microgliosis, astrogliosis, and oligodendrocyte injury. Our knowledge of glial biology during development is exponentially expanding but hasn't developed sufficiently for development of effective neuroregenerative therapies. This review summarizes the current state of knowledge for the roles of glia in infants with EoP and its animal models, and a description of known glial-cell interactions in the context of EoP, such as the roles for border-associated macrophages. The field of perinatal medicine is relatively small but has worked passionately to improve our understanding of the etiology of EoP coupled with detailed mechanistic studies of pre-clinical and human cohorts. A primary finding from this review is that expanding our collaborations with computational biologists, working together to understand the complexity of glial subtypes, glial maturation, and the impacts of EoP in the short and long term will be key to the design of therapies that improve outcomes.
Collapse
Affiliation(s)
| | - Cindy Bokobza
- NeuroDiderot, INSERMUniversité Paris CitéParisFrance
| | | | - Isabelle K. Shearer
- School of Health and Biomedical SciencesSTEM College, RMIT UniversityBundooraVictoriaAustralia
| | - Veronique E. Miron
- Barlo Multiple Sclerosis CentreSt. Michael's HospitalTorontoOntarioCanada
- Department of ImmunologyUniversity of TorontoTorontoOntarioCanada
- College of Medicine and Veterinary MedicineThe Dementia Research Institute at The University of EdinburghEdinburghUK
| | - Rejane Rua
- CNRS, INSERM, Centre d'Immunologie de Marseille‐Luminy (CIML), Turing Centre for Living SystemsAix‐Marseille UniversityMarseilleFrance
| | - Samantha M. Matta
- School of Health and Biomedical SciencesSTEM College, RMIT UniversityBundooraVictoriaAustralia
| | - Elisa L. Hill‐Yardin
- School of Health and Biomedical SciencesSTEM College, RMIT UniversityBundooraVictoriaAustralia
| | - Bobbi Fleiss
- NeuroDiderot, INSERMUniversité Paris CitéParisFrance
- School of Health and Biomedical SciencesSTEM College, RMIT UniversityBundooraVictoriaAustralia
| | | |
Collapse
|
2
|
Morales Pantoja IE, Ding L, Leite PEC, Marques SA, Romero JC, Alam El Din DM, Zack DJ, Chamling X, Smirnova L. A Novel Approach to Increase Glial Cell Populations in Brain Microphysiological Systems. Adv Biol (Weinh) 2023:e2300198. [PMID: 38062868 PMCID: PMC11156795 DOI: 10.1002/adbi.202300198] [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: 05/30/2023] [Revised: 10/14/2023] [Indexed: 12/19/2023]
Abstract
Brain microphysiological systems (bMPS) recapitulate human brain cellular architecture and functionality more closely than traditional monolayer cultures and have become increasingly relevant for the study of neurological function in health and disease. Existing 3D brain models vary in reflecting the relative populations of different cell types present in the human brain. Most models consist mainly of neurons, while glial cells represent a smaller portion of the cell populations. Here, by means of a chemically defined glial-enriched medium (GEM), an improved method to expand the population of astrocytes and oligodendrocytes without compromising neuronal differentiation in bMPS, is presented. An important finding is that astrocytes also change in morphology when cultured in GEM, more closely recapitulating primary culture astrocytes. GEM bMPS are electro-chemically active and show different patterns of calcium staining and flux. Synaptic vesicles and terminals observed by electron microscopy are also present. No significant changes in neuronal differentiation are observed by gene expression, however, GEM enhanced neurite outgrowth and cell migration, and differentially modulated neuronal maturation in two different cell lines. These results have the potential to significantly improve functionality of bMPS for the study of neurological diseases and drug discovery, contributing to the unmet need for safe human models.
Collapse
Affiliation(s)
- Itzy E Morales Pantoja
- Center for Alternatives to Animal Testing (CAAT), Department of Environmental Health and Engineering, Bloomberg School of Public Health Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Lixuan Ding
- Center for Alternatives to Animal Testing (CAAT), Department of Environmental Health and Engineering, Bloomberg School of Public Health Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Paulo E C Leite
- Clinical Research Unit of the Antonio Pedro Hospital, Fluminense Federal University, Niteroi, 24033-900, Brazil
| | - Suelen A Marques
- Laboratory of Neural Regeneration and Function, Neurobiology Department, Biology Institute, Fluminense Federal University, Niteroi, 24210-201, Brazil
| | - July Carolina Romero
- Center for Alternatives to Animal Testing (CAAT), Department of Environmental Health and Engineering, Bloomberg School of Public Health Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Dowlette-Mary Alam El Din
- Center for Alternatives to Animal Testing (CAAT), Department of Environmental Health and Engineering, Bloomberg School of Public Health Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Donald J Zack
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Xitiz Chamling
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Lena Smirnova
- Center for Alternatives to Animal Testing (CAAT), Department of Environmental Health and Engineering, Bloomberg School of Public Health Johns Hopkins University, Baltimore, MD, 21205, USA
| |
Collapse
|
3
|
Napier M, Reynolds K, Scott AL. Glial-mediated dysregulation of neurodevelopment in Fragile X Syndrome. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 173:187-215. [PMID: 37993178 DOI: 10.1016/bs.irn.2023.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Astrocytes are highly involved in a multitude of developmental processes that are known to be dysregulated in Fragile X Syndrome. Here, we examine these processes individually and review the roles astrocytes play in contributing to the pathology of this syndrome. As a growing area of interest in the field, new and exciting insight is continually emerging. Understanding these glial-mediated roles is imperative for elucidating the underlying molecular mechanisms at play, not only in Fragile X Syndrome, but also other ASD-related disorders. Understanding these roles will be central to the future development of effective, clinically-relevant treatments of these disorders.
Collapse
Affiliation(s)
- M Napier
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada; Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Canada
| | - K Reynolds
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Canada; Department of Neuroscience, Tufts University School of Medicine, Boston, United States
| | - A L Scott
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada; Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Canada.
| |
Collapse
|
4
|
Pantoja IEM, Ding L, Leite PEC, Marques SA, Romero JC, Din DMAE, Zack DJ, Chamling X, Smirnova L. A novel approach to increase glial cell populations in brain microphysiological systems. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.14.557775. [PMID: 37745321 PMCID: PMC10515937 DOI: 10.1101/2023.09.14.557775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Brain microphysiological systems (bMPS), which recapitulate human brain cellular architecture and functionality more closely than traditional monolayer cultures, have become a practical, non-invasive, and increasingly relevant platform for the study of neurological function in health and disease. These models include 3D spheroids and organoids as well as organ-on-chip models. Currently, however, existing 3D brain models vary in reflecting the relative populations of the different cell types present in the human brain. Most of the models consist mainly of neurons, while glial cells represent a smaller portion of the cell populations. Here, by means of a chemically defined glial-enriched medium (GEM), we present an improved method to expand the population of astrocytes and oligodendrocytes without compromising neuronal differentiation in bMPS. An important finding is that astrocytes not only increased in number but also changed in morphology when cultured in GEM, more closely recapitulating primary culture astrocytes. We demonstrate oligodendrocyte and astrocyte enrichment in GEM bMPS using a variety of complementary methods. We found that GEM bMPS are electro-chemically active and showed different patterns of Ca +2 staining and flux. Synaptic vesicles and terminals observed by electron microscopy were also present. No significant changes in neuronal differentiation were observed by gene expression, however, GEM enhanced neurite outgrowth and cell migration, and differentially modulated neuronal maturation in two different iPSC lines. Our results have the potential to significantly improve in vivo-like functionality of bMPS for the study of neurological diseases and drug discovery, contributing to the unmet need for safe human models.
Collapse
|
5
|
Gomez-Godinez V, Li H, Kuang Y, Liu C, Shi L, Berns MW. A single cell death is disruptive to spontaneous Ca2+ activity in astrocytes. Front Cell Neurosci 2022; 16:945737. [PMID: 35966204 PMCID: PMC9364045 DOI: 10.3389/fncel.2022.945737] [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: 05/16/2022] [Accepted: 07/08/2022] [Indexed: 11/13/2022] Open
Abstract
Astrocytes in the brain are rapidly recruited to sites of injury where they phagocytose damaged material and take up neurotransmitters and ions to avoid the spreading of damaging molecules. In this study we investigate the calcium (Ca2+) response in astrocytes to nearby cell death. To induce cell death in a nearby cell we utilized a laser nanosurgery system to photolyze a selected cell from an established astrocyte cell line (Ast1). Our results show that the lysis of a nearby cell is disruptive to surrounding cells' Ca2+ activity. Additionally, astrocytes exhibit a Ca2+ transient in response to cell death which differs from the spontaneous oscillations occurring in astrocytes prior to cell lysis. We show that the primary source of the Ca2+ transient is the endoplasmic reticulum.
Collapse
Affiliation(s)
- Veronica Gomez-Godinez
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
| | - Huayan Li
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
| | - Yixuan Kuang
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
| | - Changchen Liu
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
| | - Linda Shi
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
| | - Michael W. Berns
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, San Diego, CA, United States
- Department of Biomedical Engineering, Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- Department of Developmental and Cell Biology, School of Biological Sciences, University of California, Irvine, Irvine, CA, United States
- *Correspondence: Michael W. Berns
| |
Collapse
|
6
|
Hybrid biodegradable electrospun scaffolds based on poly(l-lactic acid) and reduced graphene oxide with improved piezoelectric response. Polym J 2022. [DOI: 10.1038/s41428-022-00669-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
7
|
Sherwood MW, Arizono M, Panatier A, Mikoshiba K, Oliet SHR. Astrocytic IP 3Rs: Beyond IP 3R2. Front Cell Neurosci 2021; 15:695817. [PMID: 34393726 PMCID: PMC8363081 DOI: 10.3389/fncel.2021.695817] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/30/2021] [Indexed: 12/31/2022] Open
Abstract
Astrocytes are sensitive to ongoing neuronal/network activities and, accordingly, regulate neuronal functions (synaptic transmission, synaptic plasticity, behavior, etc.) by the context-dependent release of several gliotransmitters (e.g., glutamate, glycine, D-serine, ATP). To sense diverse input, astrocytes express a plethora of G-protein coupled receptors, which couple, via Gi/o and Gq, to the intracellular Ca2+ release channel IP3-receptor (IP3R). Indeed, manipulating astrocytic IP3R-Ca2+ signaling is highly consequential at the network and behavioral level: Depleting IP3R subtype 2 (IP3R2) results in reduced GPCR-Ca2+ signaling and impaired synaptic plasticity; enhancing IP3R-Ca2+ signaling affects cognitive functions such as learning and memory, sleep, and mood. However, as a result of discrepancies in the literature, the role of GPCR-IP3R-Ca2+ signaling, especially under physiological conditions, remains inconclusive. One primary reason for this could be that IP3R2 has been used to represent all astrocytic IP3Rs, including IP3R1 and IP3R3. Indeed, IP3R1 and IP3R3 are unique Ca2+ channels in their own right; they have unique biophysical properties, often display distinct distribution, and are differentially regulated. As a result, they mediate different physiological roles to IP3R2. Thus, these additional channels promise to enrich the diversity of spatiotemporal Ca2+ dynamics and provide unique opportunities for integrating neuronal input and modulating astrocyte–neuron communication. The current review weighs evidence supporting the existence of multiple astrocytic-IP3R isoforms, summarizes distinct sub-type specific properties that shape spatiotemporal Ca2+ dynamics. We also discuss existing experimental tools and future refinements to better recapitulate the endogenous activities of each IP3R isoform.
Collapse
Affiliation(s)
- Mark W Sherwood
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, Bordeaux, France
| | - Misa Arizono
- University of Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, Bordeaux, France
| | - Aude Panatier
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, Bordeaux, France
| | - Katsuhiko Mikoshiba
- ShanghaiTech University, Shanghai, China.,Faculty of Science, Toho University, Funabashi, Japan.,RIKEN CLST, Kobe, Japan
| | - Stéphane H R Oliet
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, Bordeaux, France
| |
Collapse
|
8
|
Antrobus S, Pressly B, Nik AM, Wulff H, Pessah IN. Structure-Activity Relationship of Neuroactive Steroids, Midazolam, and Perampanel Toward Mitigating Tetramine-Triggered Activity in Murine Hippocampal Neuronal Networks. Toxicol Sci 2021; 180:325-341. [PMID: 33483729 PMCID: PMC8599726 DOI: 10.1093/toxsci/kfab007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tetramethylenedisulfotetramine (tetramine or TETS), a potent convulsant, triggers abnormal electrical spike activity (ESA) and synchronous Ca2+ oscillation (SCO) patterns in cultured neuronal networks by blocking gamma-aminobutyric acid (GABAA) receptors. Murine hippocampal neuronal/glial cocultures develop extensive dendritic connectivity between glutamatergic and GABAergic inputs and display two distinct SCO patterns when imaged with the Ca2+ indicator Fluo-4: Low amplitude SCO events (LASE) and High amplitude SCO events (HASE) that are dependent on TTX-sensitive network electrical spike activity (ESA). Acute TETS (3.0 µM) increased overall network SCO amplitude and decreased SCO frequency by stabilizing HASE and suppressing LASE while increasing ESA. In multielectrode arrays, TETS also increased burst frequency and synchronicity. In the presence of TETS (3.0 µM), the clinically used anticonvulsive perampanel (0.1-3.0 µM), a noncompetitive AMPAR antagonist, suppressed all SCO activity, whereas the GABAA receptor potentiator midazolam (1.0-30 µM), the current standard of care, reciprocally suppressed HASE and stabilized LASE. The neuroactive steroid (NAS) allopregnanolone (0.1-3.0 µM) normalized TETS-triggered patterns by selectively suppressing HASE and increasing LASE, a pharmacological pattern distinct from its epimeric form eltanolone, ganaxolone, alphaxolone, and XJ-42, which significantly potentiated TETS-triggered HASE in a biphasic manner. Cortisol failed to mitigate TETS-triggered patterns and at >1 µM augmented them. Combinations of allopregnanolone and midazolam were significantly more effective at normalizing TETS-triggered SCO patterns, ESA patterns, and more potently enhanced GABA-activated Cl- current, than either drug alone.
Collapse
Affiliation(s)
- Shane Antrobus
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, California 95616, USA
| | - Brandon Pressly
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, California 95616, USA
| | - Atefeh Mousavi Nik
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, California 95616, USA
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, California 95616, USA
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, California 95616, USA
| |
Collapse
|
9
|
Okubo Y. Astrocytic Ca2+ signaling mediated by the endoplasmic reticulum in health and disease. J Pharmacol Sci 2020; 144:83-88. [DOI: 10.1016/j.jphs.2020.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/19/2022] Open
|
10
|
Jaudon F, Chiacchiaretta M, Albini M, Ferroni S, Benfenati F, Cesca F. Kidins220/ARMS controls astrocyte calcium signaling and neuron-astrocyte communication. Cell Death Differ 2020; 27:1505-1519. [PMID: 31624352 PMCID: PMC7206051 DOI: 10.1038/s41418-019-0431-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 09/30/2019] [Accepted: 09/30/2019] [Indexed: 12/22/2022] Open
Abstract
Through their ability to modulate synaptic transmission, glial cells are key regulators of neuronal circuit formation and activity. Kidins220/ARMS (kinase-D interacting substrate of 220 kDa/ankyrin repeat-rich membrane spanning) is one of the key effectors of the neurotrophin pathways in neurons where it is required for differentiation, survival, and plasticity. However, its role in glial cells remains largely unknown. Here, we show that ablation of Kidins220 in primary cultured astrocytes induced defects in calcium (Ca2+) signaling that were linked to altered store-operated Ca2+ entry and strong overexpression of the transient receptor potential channel TRPV4. Moreover, Kidins220-/- astrocytes were more sensitive to genotoxic stress. We also show that Kidins220 expression in astrocytes is required for the establishment of proper connectivity of cocultured wild-type neurons. Altogether, our data reveal a previously unidentified role for astrocyte-expressed Kidins220 in the control of glial Ca2+ dynamics, survival/death pathways and astrocyte-neuron communication.
Collapse
Affiliation(s)
- Fanny Jaudon
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132, Genova, Italy
| | - Martina Chiacchiaretta
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132, Genova, Italy
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Martina Albini
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132, Genova, Italy
- Department of Experimental Medicine, University of Genova, 16132, Genova, Italy
| | - Stefano Ferroni
- Department of Pharmacy and Biotechnology, University of Bologna, 40126, Bologna, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Fabrizia Cesca
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, 16132, Genova, Italy.
- Department of Life Sciences, University of Trieste, 34127, Trieste, Italy.
| |
Collapse
|
11
|
Hippocampal neurons in direct contact with astrocytes exposed to amyloid β 25-35 exhibit reduced excitatory synaptic transmission. IBRO Rep 2019; 7:34-41. [PMID: 31388597 PMCID: PMC6669318 DOI: 10.1016/j.ibror.2019.07.1719] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 07/16/2019] [Indexed: 12/28/2022] Open
Abstract
We exposed astrocytes to Aβ 25-35 and then co-cultured them with primary hippocampal neurons. The Aβ25-35-exposed astrocytes lowered excitatory postsynaptic release and the size of the readily releasable synaptic pool. The number of excitatory synapses was reduced by direct contact between Aβ25-35-exposed astrocytes and hippocampal neurons. The dendritic branching was decreased by direct contact between Aβ25-35-exposed astrocytes and hippocampal neurons. The number of excitatory synapses and dendrite branches were conserved by putting distance from Aβ25-35-exposed astrocytes.
Amyloid β protein (Aβ) is closely related to the progression of Alzheimer's disease because senile plaques consisting of Aβ cause synaptic depression and synaptic abnormalities. In the central nervous system, astrocytes are a major glial cell type that contribute to the modulation of synaptic transmission and synaptogenesis. In this study, we examined whether astrocytes exposed to Aβ fragment 25-35 (Aβ25-35) affect synaptic transmission. We show that synaptic transmission by hippocampal neurons was inhibited by astrocytes exposed to Aβ25-35. The Aβ25-35-exposed astrocytes lowered excitatory postsynaptic release and the size of the readily releasable synaptic pool. The number of excitatory synapses was also reduced. However, the number of excitatory synapses was unchanged unless there was direct contact between Aβ25-35-exposed astrocytes and hippocampal neurons. These data indicate that direct contact between Aβ25-35-exposed astrocytes and neurons is critical for inhibiting synaptic transmission in the progression of Alzheimer’s disease.
Collapse
|
12
|
Aberrant Calcium Signals in Reactive Astrocytes: A Key Process in Neurological Disorders. Int J Mol Sci 2019; 20:ijms20040996. [PMID: 30823575 PMCID: PMC6413203 DOI: 10.3390/ijms20040996] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/20/2019] [Accepted: 02/21/2019] [Indexed: 02/06/2023] Open
Abstract
Astrocytes are abundant cells in the brain that regulate multiple aspects of neural tissue homeostasis by providing structural and metabolic support to neurons, maintaining synaptic environments and regulating blood flow. Recent evidence indicates that astrocytes also actively participate in brain functions and play a key role in brain disease by responding to neuronal activities and brain insults. Astrocytes become reactive in response to injury and inflammation, which is typically described as hypertrophy with increased expression of glial fibrillary acidic protein (GFAP). Reactive astrocytes are frequently found in many neurological disorders and are a hallmark of brain disease. Furthermore, reactive astrocytes may drive the initiation and progression of disease processes. Recent improvements in the methods to visualize the activity of reactive astrocytes in situ and in vivo have helped elucidate their functions. Ca2+ signals in reactive astrocytes are closely related to multiple aspects of disease and can be a good indicator of disease severity/state. In this review, we summarize recent findings concerning reactive astrocyte Ca2+ signals. We discuss the molecular mechanisms underlying aberrant Ca2+ signals in reactive astrocytes and the functional significance of aberrant Ca2+ signals in neurological disorders.
Collapse
|
13
|
Okubo Y, Mikami Y, Kanemaru K, Iino M. Role of Endoplasmic Reticulum-Mediated Ca 2+ Signaling in Neuronal Cell Death. Antioxid Redox Signal 2018; 29:1147-1157. [PMID: 29361832 DOI: 10.1089/ars.2018.7498] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
SIGNIFICANCE Properly controlled intracellular Ca2+ dynamics is crucial for regulation of neuronal function and survival in the central nervous system. The endoplasmic reticulum (ER), a major intracellular Ca2+ store, plays a critical role as a source and sink for neuronal Ca2+. Recent Advances: Accumulating evidence indicates that disrupted ER Ca2+ signaling is involved in neuronal cell death under various pathological conditions, providing novel insight into neurodegenerative disease mechanisms. CRITICAL ISSUES We summarize current knowledge concerning the relationship between abnormal ER Ca2+ dynamics and neuronal cell death. We also introduce recent technical advances for probing ER intraluminal Ca2+ dynamics with unprecedented spatiotemporal resolution. FUTURE DIRECTIONS Further studies on ER Ca2+ signaling are expected to provide progress for unmet medical needs in neurodegenerative disease. Antioxid. Redox Signal. 29, 1147-1157.
Collapse
Affiliation(s)
- Yohei Okubo
- 1 Department of Pharmacology, Graduate School of Medicine, The University of Tokyo , Tokyo, Japan
| | - Yoshinori Mikami
- 2 Department of Physiology, School of Medicine, Faculty of Medicine, Toho University , Tokyo, Japan
| | - Kazunori Kanemaru
- 1 Department of Pharmacology, Graduate School of Medicine, The University of Tokyo , Tokyo, Japan .,3 Department of Cellular and Molecular Pharmacology, Nihon University School of Medicine , Tokyo, Japan
| | - Masamitsu Iino
- 3 Department of Cellular and Molecular Pharmacology, Nihon University School of Medicine , Tokyo, Japan
| |
Collapse
|
14
|
Okubo Y, Kanemaru K, Suzuki J, Kobayashi K, Hirose K, Iino M. Inositol 1,4,5-trisphosphate receptor type 2-independent Ca2+
release from the endoplasmic reticulum in astrocytes. Glia 2018; 67:113-124. [DOI: 10.1002/glia.23531] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/13/2018] [Accepted: 08/15/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Yohei Okubo
- Department of Pharmacology; Graduate School of Medicine, The University of Tokyo; Tokyo Japan
| | - Kazunori Kanemaru
- Department of Pharmacology; Graduate School of Medicine, The University of Tokyo; Tokyo Japan
- Department of Cellular and Molecular Pharmacology; Nihon University School of Medicine; Tokyo Japan
| | - Junji Suzuki
- Department of Physiology; University of California San Francisco; San Francisco California
| | - Kenta Kobayashi
- Section of Viral Vector Development; National Institute for Physiological Sciences; Okazaki Japan
- The Graduate University for Advanced Studies (SOKENDAI); Hayama Japan
| | - Kenzo Hirose
- Department of Neurobiology; Graduate School of Medicine, The University of Tokyo; Tokyo Japan
| | - Masamitsu Iino
- Department of Cellular and Molecular Pharmacology; Nihon University School of Medicine; Tokyo Japan
| |
Collapse
|
15
|
Kanemaru K. [Analysis of astrocytic function using Ca 2+ imaging]. Nihon Yakurigaku Zasshi 2018; 151:206-212. [PMID: 29760365 DOI: 10.1254/fpj.151.206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Accumulating evidence shows astrocytic contribution to brain function and diseases, however, the function of astrocytes remains to be uncovered. Dynamic changes in the intracellular Ca2+ level in astrocytes are one of the outstanding indexes of ongoing astrocytic activity. Therefore, we tried to uncover astrocytic function using approaches combined with Ca2+ imaging. We showed that astrocytes promote neuronal growth and survival after injury via Ca2+-dependent regulation of a cell adhesion protein, N-cadherin. Furthermore, we developed a method for the monitoring of astrocytic Ca2+ signals in living mouse brain, and found a previously unidentified pattern of spontaneous Ca2+ signals, which are preferably displayed in astrocytic fine processes. These findings and methods are promising to provide further information of astrocytic function, which can contribute to development of pharmacology.
Collapse
Affiliation(s)
- Kazunori Kanemaru
- Department of Cellular and Molecular Pharmacology, Graduate School of Medicine, The University of Tokyo
| |
Collapse
|
16
|
Kardos J, Héja L, Jemnitz K, Kovács R, Palkovits M. The nature of early astroglial protection-Fast activation and signaling. Prog Neurobiol 2017; 153:86-99. [PMID: 28342942 DOI: 10.1016/j.pneurobio.2017.03.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 09/22/2016] [Accepted: 03/05/2017] [Indexed: 12/14/2022]
Abstract
Our present review is focusing on the uniqueness of balanced astroglial signaling. The balance of excitatory and inhibitory signaling within the CNS is mainly determined by sharp synaptic transients of excitatory glutamate (Glu) and inhibitory γ-aminobutyrate (GABA) acting on the sub-second timescale. Astroglia is involved in excitatory chemical transmission by taking up i) Glu through neurotransmitter-sodium transporters, ii) K+ released due to presynaptic action potential generation, and iii) water keeping osmotic pressure. Glu uptake-coupled Na+ influx may either ignite long-range astroglial Ca2+ transients or locally counteract over-excitation via astroglial GABA release and increased tonic inhibition. Imbalance of excitatory and inhibitory drives is associated with a number of disease conditions, including prevalent traumatic and ischaemic injuries or the emergence of epilepsy. Therefore, when addressing the potential of early therapeutic intervention, astroglial signaling functions combating progress of Glu excitotoxicity is of critical importance. We suggest, that excitotoxicity is linked primarily to over-excitation induced by the impairment of astroglial Glu uptake and/or GABA release. Within this framework, we discuss the acute alterations of Glu-cycling and metabolism and conjecture the therapeutic promise of regulation. We also confer the role played by key carrier proteins and enzymes as well as their interplay at the molecular, cellular, and organ levels. Moreover, based on our former studies, we offer potential prospect on the emerging theme of astroglial succinate sensing in course of Glu excitotoxicity.
Collapse
Affiliation(s)
- Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary.
| | - László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
| | - Katalin Jemnitz
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
| | - Richárd Kovács
- Institute of Neurophysiology, Charité - Universitätsmedizin, Berlin, Germany
| | - Miklós Palkovits
- Human Brain Tissue Bank and Laboratory, Semmelweis University, Budapest, Hungary
| |
Collapse
|
17
|
Ino D, Iino M. Schwann cell mitochondria as key regulators in the development and maintenance of peripheral nerve axons. Cell Mol Life Sci 2017; 74:827-835. [PMID: 27638763 PMCID: PMC11107563 DOI: 10.1007/s00018-016-2364-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/29/2016] [Accepted: 09/09/2016] [Indexed: 01/13/2023]
Abstract
Formation of myelin sheaths by Schwann cells (SCs) enables rapid and efficient transmission of action potentials in peripheral axons, and disruption of myelination results in disorders that involve decreased sensory and motor functions. Given that construction of SC myelin requires high levels of lipid and protein synthesis, mitochondria, which are pivotal in cellular metabolism, may be potential regulators of the formation and maintenance of SC myelin. Supporting this notion, abnormal mitochondria are found in SCs of neuropathic peripheral nerves in both human patients and the relevant animal models. However, evidence for the importance of SC mitochondria in myelination has been limited, until recently. Several studies have recently used genetic approaches that allow SC-specific ablation of mitochondrial metabolic activity in living animals to show the critical roles of SC mitochondria in the development and maintenance of peripheral nerve axons. Here, we review current knowledge about the involvement of SC mitochondria in the formation and dysfunction of myelinated axons in the peripheral nervous system.
Collapse
Affiliation(s)
- Daisuke Ino
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Laboratory for Cell Polarity Regulation, RIKEN Quantitative Biology Center, 6-2-3, Furuedai, Suita, Osaka, 565-0874, Japan
| | - Masamitsu Iino
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
- Division of Cellular and Molecular Pharmacology, Nihon University School of Medicine, 30-1, Oyaguchi kami-cho, Itabashi-ku, Tokyo, 173-8610, Japan.
| |
Collapse
|
18
|
Mikami Y, Kanemaru K, Okubo Y, Nakaune T, Suzuki J, Shibata K, Sugiyama H, Koyama R, Murayama T, Ito A, Yamazawa T, Ikegaya Y, Sakurai T, Saito N, Kakizawa S, Iino M. Nitric Oxide-induced Activation of the Type 1 Ryanodine Receptor Is Critical for Epileptic Seizure-induced Neuronal Cell Death. EBioMedicine 2016; 11:253-261. [PMID: 27544065 PMCID: PMC5049986 DOI: 10.1016/j.ebiom.2016.08.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 08/05/2016] [Accepted: 08/12/2016] [Indexed: 01/27/2023] Open
Abstract
Status epilepticus (SE) is a life-threatening emergency that can cause neurodegeneration with debilitating neurological disorders. However, the mechanism by which convulsive SE results in neurodegeneration is not fully understood. It has been shown that epileptic seizures produce markedly increased levels of nitric oxide (NO) in the brain, and that NO induces Ca2+ release from the endoplasmic reticulum via the type 1 ryanodine receptor (RyR1), which occurs through S-nitrosylation of the intracellular Ca2+ release channel. Here, we show that through genetic silencing of NO-induced activation of the RyR1 intracellular Ca2+ release channel, neurons were rescued from seizure-dependent cell death. Furthermore, dantrolene, an inhibitor of RyR1, was protective against neurodegeneration caused by SE. These results demonstrate that NO-induced Ca2+ release via RyR is involved in SE-induced neurodegeneration, and provide a rationale for the use of RyR1 inhibitors for the prevention of brain damage following SE.
Collapse
Affiliation(s)
- Yoshinori Mikami
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Physiology, School of Medicine, Faculty of Medicine, Toho University, 5-21-16 Omori-Nishi, Ota-ku, Tokyo 143-8540, Japan
| | - Kazunori Kanemaru
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yohei Okubo
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takuya Nakaune
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Junji Suzuki
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazuki Shibata
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroki Sugiyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takashi Murayama
- Department of Pharmacology, Graduate School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Akihiro Ito
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan; Department of Neurosurgery, Graduate School of Medicine, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 117-003, Japan
| | - Toshiko Yamazawa
- Department of Molecular Physiology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takashi Sakurai
- Department of Pharmacology, Graduate School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Nobuhito Saito
- Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Sho Kakizawa
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Masamitsu Iino
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Cellular and Molecular Pharmacology, Nihon University School of Medicine, 30-1 Oyaguchi Kami-cho, Itabashi-ku, Tokyo 173-8610, Japan.
| |
Collapse
|
19
|
Chlorogenic acid, a polyphenol in coffee, protects neurons against glutamate neurotoxicity. Life Sci 2015; 139:69-74. [DOI: 10.1016/j.lfs.2015.08.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 07/25/2015] [Accepted: 08/01/2015] [Indexed: 11/19/2022]
|
20
|
Ino D, Sagara H, Suzuki J, Kanemaru K, Okubo Y, Iino M. Neuronal Regulation of Schwann Cell Mitochondrial Ca(2+) Signaling during Myelination. Cell Rep 2015; 12:1951-9. [PMID: 26365190 DOI: 10.1016/j.celrep.2015.08.039] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 07/01/2015] [Accepted: 08/12/2015] [Indexed: 11/24/2022] Open
Abstract
Schwann cells (SCs) myelinate peripheral neurons to promote the rapid conduction of action potentials, and the process of myelination is known to be regulated by signals from axons to SCs. Given that SC mitochondria are one of the potential regulators of myelination, we investigated whether SC mitochondria are regulated by axonal signaling. Here, we show a purinergic mechanism that sends information from neurons to SC mitochondria during myelination. Our results show that electrical stimulation of rat sciatic nerve increases extracellular ATP levels enough to activate purinergic receptors. Indeed, electrical stimulation of sciatic nerves induces Ca(2+) increases in the cytosol and the mitochondrial matrix of surrounding SCs via purinergic receptor activation. Chronic suppression of this pathway during active myelination suppressed the longitudinal and radial development of myelinating SCs and caused hypomyelination. These results demonstrate a neuron-to-SC mitochondria signaling, which is likely to have an important role in proper myelination.
Collapse
Affiliation(s)
- Daisuke Ino
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Hiroshi Sagara
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Tokyo 113-8654, Japan
| | - Junji Suzuki
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Kazunori Kanemaru
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Yohei Okubo
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan
| | - Masamitsu Iino
- Department of Pharmacology, The University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan.
| |
Collapse
|
21
|
Fields RD, Woo DH, Basser PJ. Glial Regulation of the Neuronal Connectome through Local and Long-Distant Communication. Neuron 2015; 86:374-86. [PMID: 25905811 DOI: 10.1016/j.neuron.2015.01.014] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
If "the connectome" represents a complete map of anatomical and functional connectivity in the brain, it should also include glia. Glia define and regulate both the brain's anatomical and functional connectivity over a broad range of length scales, spanning the whole brain to subcellular domains of synaptic interactions. This Perspective article examines glial interactions with the neuronal connectome (including long-range networks, local circuits, and individual synaptic connections) and highlights opportunities for future research. Our understanding of the structure and function of the neuronal connectome would be incomplete without an understanding of how all types of glia contribute to neuronal connectivity and function, from single synapses to circuits.
Collapse
Affiliation(s)
- R Douglas Fields
- Nervous System Development and Plasticity Section, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
| | - Dong Ho Woo
- Nervous System Development and Plasticity Section, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892, USA
| | - Peter J Basser
- Section on Tissue Biophysics and Biomimetics, Program on Pediatric Imaging and Tissue Sciences, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| |
Collapse
|
22
|
Li H, Wang X, Zhang N, Gottipati MK, Parpura V, Ding S. Imaging of mitochondrial Ca2+ dynamics in astrocytes using cell-specific mitochondria-targeted GCaMP5G/6s: mitochondrial Ca2+ uptake and cytosolic Ca2+ availability via the endoplasmic reticulum store. Cell Calcium 2014; 56:457-66. [PMID: 25443655 DOI: 10.1016/j.ceca.2014.09.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 09/20/2014] [Accepted: 09/22/2014] [Indexed: 11/20/2022]
Abstract
Mitochondrial Ca(2+) plays a critical physiological role in cellular energy metabolism and signaling, and its overload contributes to various pathological conditions including neuronal apoptotic death in neurological diseases. Live cell mitochondrial Ca(2+) imaging is an important approach to understand mitochondrial Ca(2+) dynamics. Recently developed GCaMP genetically-encoded Ca(2+) indicators provide unique opportunity for high sensitivity/resolution and cell type-specific mitochondrial Ca(2+) imaging. In the current study, we implemented cell-specific mitochondrial targeting of GCaMP5G/6s (mito-GCaMP5G/6s) and used two-photon microscopy to image astrocytic and neuronal mitochondrial Ca(2+) dynamics in culture, revealing Ca(2+) uptake mechanism by these organelles in response to cell stimulation. Using these mitochondrial Ca(2+) indicators, our results show that mitochondrial Ca(2+) uptake in individual mitochondria in cultured astrocytes and neurons can be seen after stimulations by ATP and glutamate, respectively. We further studied the dependence of mitochondrial Ca(2+) dynamics on cytosolic Ca(2+) changes following ATP stimulation in cultured astrocytes by simultaneously imaging mitochondrial and cytosolic Ca(2+) increase using mito-GCaMP5G and a synthetic organic Ca(2+) indicator, x-Rhod-1, respectively. Combined with molecular intervention in Ca(2+) signaling pathway, our results demonstrated that the mitochondrial Ca(2+) uptake is tightly coupled with inositol 1,4,5-trisphosphate receptor-mediated Ca(2+) release from the endoplasmic reticulum and the activation of G protein-coupled receptors. The current study provides a novel approach to image mitochondrial Ca(2+) dynamics as well as Ca(2+) interplay between the endoplasmic reticulum and mitochondria, which is relevant for neuronal and astrocytic functions in health and disease.
Collapse
Affiliation(s)
- Hailong Li
- Dalton Cardiovascular Research Center, Columbia, MO 65211, United States; Department of Bioengineering, University of Missouri, Columbia, MO 65211, United States
| | - Xiaowan Wang
- Department of Bioengineering, University of Missouri, Columbia, MO 65211, United States
| | - Nannan Zhang
- Dalton Cardiovascular Research Center, Columbia, MO 65211, United States
| | - Manoj K Gottipati
- Department of Neurobiology, University of Alabama, Birmingham, AL 35294, United States
| | - Vladimir Parpura
- Department of Neurobiology, University of Alabama, Birmingham, AL 35294, United States; Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia
| | - Shinghua Ding
- Dalton Cardiovascular Research Center, Columbia, MO 65211, United States; Department of Bioengineering, University of Missouri, Columbia, MO 65211, United States.
| |
Collapse
|
23
|
Okubo Y. [Visualization of metabotropic glutamate-receptor signaling]. Nihon Yakurigaku Zasshi 2014; 144:76-80. [PMID: 25109520 DOI: 10.1254/fpj.144.76] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
24
|
Brazhe A, Mathiesen C, Lind B, Rubin A, Lauritzen M. Multiscale vision model for event detection and reconstruction in two-photon imaging data. NEUROPHOTONICS 2014; 1:011012. [PMID: 26157968 PMCID: PMC4479008 DOI: 10.1117/1.nph.1.1.011012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 07/22/2014] [Accepted: 07/25/2014] [Indexed: 06/04/2023]
Abstract
Reliable detection of calcium waves in multiphoton imaging data is challenging because of the low signal-to-noise ratio and because of the unpredictability of the time and location of these spontaneous events. This paper describes our approach to calcium wave detection and reconstruction based on a modified multiscale vision model, an object detection framework based on the thresholding of wavelet coefficients and hierarchical trees of significant coefficients followed by nonlinear iterative partial object reconstruction, for the analysis of two-photon calcium imaging data. The framework is discussed in the context of detection and reconstruction of intercellular glial calcium waves. We extend the framework by a different decomposition algorithm and iterative reconstruction of the detected objects. Comparison with several popular state-of-the-art image denoising methods shows that performance of the multiscale vision model is similar in the denoising, but provides a better segmenation of the image into meaningful objects, whereas other methods need to be combined with dedicated thresholding and segmentation utilities.
Collapse
Affiliation(s)
- Alexey Brazhe
- Moscow State University, Faculty of Biology, Moscow 119234, Russia
| | - Claus Mathiesen
- Copenhagen University, Institute for Neuroscience and Pharmacology, Copenhagen 2200, Denmark
| | - Barbara Lind
- Copenhagen University, Institute for Neuroscience and Pharmacology, Copenhagen 2200, Denmark
| | - Andrey Rubin
- Moscow State University, Faculty of Biology, Moscow 119234, Russia
| | - Martin Lauritzen
- Copenhagen University, Institute for Neuroscience and Pharmacology, Copenhagen 2200, Denmark
| |
Collapse
|
25
|
Imaging intraorganellar Ca2+ at subcellular resolution using CEPIA. Nat Commun 2014; 5:4153. [PMID: 24923787 PMCID: PMC4082642 DOI: 10.1038/ncomms5153] [Citation(s) in RCA: 332] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 05/16/2014] [Indexed: 12/19/2022] Open
Abstract
The endoplasmic reticulum (ER) and mitochondria accumulate Ca2+ within their lumens to regulate numerous cell functions. However, determining the dynamics of intraorganellar Ca2+ has proven to be difficult. Here we describe a family of genetically encoded Ca2+ indicators, named calcium-measuring organelle-entrapped protein indicators (CEPIA), which can be utilized for intraorganellar Ca2+ imaging. CEPIA, which emit green, red or blue/green fluorescence, are engineered to bind Ca2+ at intraorganellar Ca2+ concentrations. They can be targeted to different organelles and may be used alongside other fluorescent molecular markers, expanding the range of cell functions that can be simultaneously analysed. The spatiotemporal resolution of CEPIA makes it possible to resolve Ca2+ import into individual mitochondria while simultaneously measuring ER and cytosolic Ca2+. We have used these imaging capabilities to reveal differential Ca2+ handling in individual mitochondria. CEPIA imaging is a useful new tool to further the understanding of organellar functions. The use of intracellular calcium sensors provides important information about the dynamics of calcium signalling in cells. Here Suzuki et al. develop organelle-targeted sensors to simultaneously measure calcium concentrations in ER and mitochondria, and uncover novel insights into calcium flux in mitochondria.
Collapse
|
26
|
Abstract
Astrocytes are the predominant glial cell type in the CNS. Although astrocytes are electrically nonexcitable, their excitability is manifested by their Ca2+ signaling, which serves as a mediator of neuron-glia bidirectional interactions via tripartite synapses. Studies from in vivo two-photon imaging indicate that in healthy animals, the properties of spontaneous astrocytic Ca2+ signaling are affected by animal species, age, wakefulness and the location of astrocytes in the brain. Intercellular Ca2+ waves in astrocytes can be evoked by a variety of stimulations. In animal models of some brain disorders, astrocytes can exhibit enhanced Ca2+ excitability featured as regenerative intercellular Ca2+ waves. This review first briefly summarizes the astrocytic Ca2+ signaling pathway and the procedure of in vivo two-photon Ca2+ imaging of astrocytes. It subsequently summarizes in vivo astrocytic Ca2+ signaling in health and brain disorders from experimental studies of animal models, and discusses the possible mechanisms and therapeutic implications underlying the enhanced Ca2+ excitability in astrocytes in brain disorders. Finally, this review summarizes molecular genetic approaches used to selectively manipulate astrocyte function in vivo and their applications to study the role of astrocytes in synaptic plasticity and brain disorders.
Collapse
Affiliation(s)
- Shinghua Ding
- Dalton Cardiovascular Research Center, Department of Biological Engineering, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
27
|
Calcium-dependent N-cadherin up-regulation mediates reactive astrogliosis and neuroprotection after brain injury. Proc Natl Acad Sci U S A 2013; 110:11612-7. [PMID: 23798419 DOI: 10.1073/pnas.1300378110] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Brain injury induces phenotypic changes in astrocytes, known as reactive astrogliosis, which may influence neuronal survival. Here we show that brain injury induces inositol 1,4,5-trisphosphate (IP3)-dependent Ca(2+) signaling in astrocytes, and that the Ca(2+) signaling is required for astrogliosis. We found that type 2 IP3 receptor knockout (IP3R2KO) mice deficient in astrocytic Ca(2+) signaling have impaired reactive astrogliosis and increased injury-associated neuronal death. We identified N-cadherin and pumilio 2 (Pum2) as downstream signaling molecules, and found that brain injury induces up-regulation of N-cadherin around the injured site. This effect is mediated by Ca(2+)-dependent down-regulation of Pum2, which in turn attenuates Pum2-dependent translational repression of N-cadherin. Furthermore, we show that astrocyte-specific knockout of N-cadherin results in impairment of astrogliosis and neuroprotection. Thus, astrocytic Ca(2+) signaling and the downstream function of N-cadherin play indispensable roles in the cellular responses to brain injury. These findings define a previously unreported signaling axis required for reactive astrogliosis and neuroprotection following brain injury.
Collapse
|
28
|
Takata N, Nagai T, Ozawa K, Oe Y, Mikoshiba K, Hirase H. Cerebral blood flow modulation by Basal forebrain or whisker stimulation can occur independently of large cytosolic Ca2+ signaling in astrocytes. PLoS One 2013; 8:e66525. [PMID: 23785506 PMCID: PMC3681769 DOI: 10.1371/journal.pone.0066525] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 05/06/2013] [Indexed: 12/13/2022] Open
Abstract
We report that a brief electrical stimulation of the nucleus basalis of Meynert (NBM), the primary source of cholinergic projection to the cerebral cortex, induces a biphasic cerebral cortical blood flow (CBF) response in the somatosensory cortex of C57BL/6J mice. This CBF response, measured by laser Doppler flowmetry, was attenuated by the muscarinic type acetylcholine receptor antagonist atropine, suggesting a possible involvement of astrocytes in this type of CBF modulation. However, we find that IP3R2 knockout mice, which lack cytosolic Ca2+ surges in astrocytes, show similar CBF changes. Moreover, whisker stimulation resulted in similar degrees of CBF increase in IP3R2 knockout mice and the background strain C57BL/6J. Our results show that neural activity-driven CBF modulation could occur without large cytosolic increases of Ca2+ in astrocytes.
Collapse
Affiliation(s)
- Norio Takata
- Laboratory for Neuron-Glia Circuit, RIKEN Brain Science Institute, Wako, Saitama, Japan.
| | | | | | | | | | | |
Collapse
|
29
|
Huang L, Liu Y, Zhang P, Kang R, Liu Y, Li X, Bo L, Dong Z. In vitro dose-dependent inhibition of the intracellular spontaneous calcium oscillations in developing hippocampal neurons by ketamine. PLoS One 2013; 8:e59804. [PMID: 23555787 PMCID: PMC3610914 DOI: 10.1371/journal.pone.0059804] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 02/19/2013] [Indexed: 01/28/2023] Open
Abstract
Spatial and temporal abnormalities in the frequency and amplitude of the cytosolic calcium oscillations can impact the normal physiological functions of neuronal cells. Recent studies have shown that ketamine can affect the growth and development and even induce the apoptotic death of neurons. This study used isolated developing hippocampal neurons as its study subjects to observe the effect of ketamine on the intracellular calcium oscillations in developing hippocampal neurons and to further explore its underlying mechanism using Fluo-4-loaded laser scanning confocal microscopy. Using a semi-quantitative method to analyze the spontaneous calcium oscillatory activities, a typical type of calcium oscillation was observed in developing hippocampal neurons. In addition, the administration of NMDA (N-Methyl-D-aspartate) at a concentration of 100 µM increased the calcium oscillation amplitude. The administration of MK801 at a concentration of 40 µM inhibited the amplitude and frequency of the calcium oscillations. Our results demonstrated that an increase in the ketamine concentration, starting from 30 µM, gradually decreased the neuronal calcium oscillation amplitude. The inhibition of the calcium oscillation frequency by 300 µM ketamine was statistically significant, and the neuronal calcium oscillations were completely eliminated with the administration of 3,000 µM Ketamine. The administration of 100, 300, and 1,000 µM NMDA to the 1 mM ketamine-pretreated hippocampal neurons restored the frequency and amplitude of the calcium oscillations in a dose-dependent manner. In fact, a concentration of 1,000 µM NMDA completely reversed the decrease in the calcium oscillation frequency and amplitude that was induced by 1 mM ketamine. This study revealed that ketamine can inhibit the frequency and amplitude of the calcium oscillations in developing hippocampal neurons though the NMDAR (NMDA receptor) in a dose-dependent manner, which might highlight a possible underlying mechanism of ketamine toxicity on the rat hippocampal neurons during development.
Collapse
Affiliation(s)
- Lining Huang
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Yue Liu
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Pei Zhang
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Rongtian Kang
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Ya Liu
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Xuze Li
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Lijun Bo
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Zhenming Dong
- Department of Anesthesiology, the Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| |
Collapse
|
30
|
Mack AF, Tiedemann K. Cultures of astroglial cells derived from brain of adult cichlid fish. J Neurosci Methods 2013; 212:269-75. [DOI: 10.1016/j.jneumeth.2012.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 10/22/2012] [Accepted: 11/08/2012] [Indexed: 10/27/2022]
|
31
|
Martiáñez T, Lamarca A, Casals N, Gella A. N-cadherin expression is regulated by UTP in schwannoma cells. Purinergic Signal 2012; 9:259-70. [PMID: 23271561 DOI: 10.1007/s11302-012-9348-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 12/12/2012] [Indexed: 12/21/2022] Open
Abstract
Schwann cells (SCs) are peripheral myelinating glial cells that express the neuronal Ca(2+)-dependent cell adhesion molecule, neural cadherin (N-cadherin). N-cadherin is involved in glia-glia and axon-glia interactions and participates in many key events, which range from the control of axonal growth and guidance to synapse formation and plasticity. Extracellular UTP activates P2Y purinergic receptors and exerts short- and long-term effects on several tissues to promote wound healing. Nevertheless, the contribution of P2Y receptors in peripheral nervous system functions is not completely understood. The current study demonstrated that UTP induced a dose- and time-dependent increase in N-cadherin expression in SCs. Furthermore, N-cadherin expression was blocked by the P2 purinoceptor antagonist suramin. The increased N-cadherin expression induced by UTP was mediated by phosphorylation of mitogen-activated protein kinases (MAPKs), such as Jun N-terminal kinase, extracellular-regulated kinase and p38 kinase. Moreover, the Rho kinase inhibitor Y27632, the phospholipase C inhibitor U73122 and the protein kinase C inhibitor calphostin C attenuated the UTP-induced activation of MAPKs significantly. Extracellular UTP also modulated increased in the expression of the early transcription factors c-Fos and c-Jun. We also demonstrated that the region of the N-cadherin promoter between nucleotide positions -3698 and -2620, which contained one activator protein-1-binding site, was necessary for UTP-induced gene expression. These results suggest a novel role for P2Y purinergic receptors in the regulation of N-cadherin expression in SCs.
Collapse
Affiliation(s)
- Tania Martiáñez
- Basic Sciences Department, Faculty of Medicine and Health Sciences, Universitat International de Catalunya, Sant Cugat del Vallès, Spain
| | | | | | | |
Collapse
|
32
|
Brazhe A, Mathiesen C, Lauritzen M. Multiscale vision model highlights spontaneous glial calcium waves recorded by 2-photon imaging in brain tissue. Neuroimage 2012; 68:192-202. [PMID: 23219568 DOI: 10.1016/j.neuroimage.2012.11.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 10/26/2012] [Accepted: 11/19/2012] [Indexed: 11/17/2022] Open
Abstract
Intercellular glial calcium waves (GCW) constitute a signaling pathway which can be visualized by fluorescence imaging of cytosolic Ca(2+) changes. Reliable detection of calcium waves in multiphoton imaging data is challenging because of low signal-to-noise ratio. We modified the multiscale vision model (MVM), originally employed to detect faint objects in astronomy data to process stacks of fluorescent images. We demonstrate that the MVM identified and characterized GCWs with much higher sensitivity and detail than pixel thresholding. Origins of GCWs were often associated with prolonged secondary Ca(2+) elevations. The GCWs had variable shapes, and secondary GCWs were observed to bud from the primary, larger GCW. GCWs evaded areas shortly before occupied by a preceding GCW instead circulating around the refractory area. Blood vessels uniquely reshaped GCWs and were associated with secondary GCW events. We conclude that the MVM provides unique possibilities to study spatiotemporally correlated Ca(2+) signaling in brain tissue.
Collapse
Affiliation(s)
- Alexey Brazhe
- Department of Biophysics, Faculty of Biology, Moscow State University, 119234 Moscow, Russia.
| | | | | |
Collapse
|
33
|
Kasumu AW, Liang X, Egorova P, Vorontsova D, Bezprozvanny I. Chronic suppression of inositol 1,4,5-triphosphate receptor-mediated calcium signaling in cerebellar purkinje cells alleviates pathological phenotype in spinocerebellar ataxia 2 mice. J Neurosci 2012; 32:12786-96. [PMID: 22973002 PMCID: PMC3470884 DOI: 10.1523/jneurosci.1643-12.2012] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/27/2012] [Accepted: 07/25/2012] [Indexed: 01/07/2023] Open
Abstract
Spinocerebellar ataxia 2 (SCA2) is a neurodegenerative disorder characterized by progressive ataxia. SCA2 results from a poly(Q) (polyglutamine) expansion in the cytosolic protein ataxin-2 (Atx2). Cerebellar Purkinje cells (PCs) are primarily affected in SCA2, but the cause of PC dysfunction and death in SCA2 is poorly understood. In previous studies, we reported that mutant but not wild-type Atx2 specifically binds the inositol 1,4,5-trisphosphate receptor (InsP(3)R) and increases its sensitivity to activation by InsP3. We further proposed that the resulting supranormal calcium (Ca2+) release from the PC endoplasmic reticulum plays a key role in the development of SCA2 pathology. To test this hypothesis, we achieved a chronic suppression of InsP(3)R-mediated Ca2+ signaling by adenoassociated virus-mediated expression of the inositol 1,4,5-phosphatase (Inpp5a) enzyme (5PP) in PCs of a SCA2 transgenic mouse model. We determined that recombinant 5PP overexpression alleviated age-dependent dysfunction in the firing pattern of SCA2 PCs. We further discovered that chronic 5PP overexpression also rescued age-dependent motor incoordination and PC death in SCA2 mice. Our findings further support the important role of supranormal Ca2+ signaling in SCA2 pathogenesis and suggest that partial inhibition of InsP3-mediated Ca2+ signaling could provide therapeutic benefit for the patients afflicted with SCA2 and possibly other SCAs.
Collapse
Affiliation(s)
- Adebimpe W. Kasumu
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
| | - Xia Liang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
| | - Polina Egorova
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, St. Petersburg Technical University, 195251 St. Petersburg, Russia
| | - Daria Vorontsova
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, St. Petersburg Technical University, 195251 St. Petersburg, Russia
| | - Ilya Bezprozvanny
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, St. Petersburg Technical University, 195251 St. Petersburg, Russia
| |
Collapse
|
34
|
Ferguson TA, Scherer SS. Neuronal cadherin (NCAD) increases sensory neurite formation and outgrowth on astrocytes. Neurosci Lett 2012; 522:108-12. [PMID: 22698587 DOI: 10.1016/j.neulet.2012.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/01/2012] [Accepted: 06/04/2012] [Indexed: 11/26/2022]
Abstract
We examined the neurite outgrowth of sensory neurons on astrocytes following the genetic deletion of N-cadherin (NCAD). Deletion abolished immunostaining for NCAD and the other classical cadherins, indicating that NCAD is likely the only classical cadherin expressed by astrocytes. Only 38% of neurons grown on NCAD-deficient astrocytes for 24 h produced neurites, as compared to 74% of neurons grown on NCAD-expressing astrocytes. Of the neurons that produced neurites, those grown on NCAD-deficient astrocytes had a mean total length of 378 μm, as compared to 1093 μm for neurons grown on NCAD-expressing astrocytes. Thus, the loss of NCAD greatly impairs the formation and extension neurites on astrocytes.
Collapse
Affiliation(s)
- Toby A Ferguson
- Department of Neurology, Temple University and Shriners Pediatric Research Center, Philadelphia, PA 19140, USA.
| | | |
Collapse
|
35
|
Mitochondrial Ca(2+) signals in autophagy. Cell Calcium 2012; 52:44-51. [PMID: 22459281 DOI: 10.1016/j.ceca.2012.03.001] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 02/29/2012] [Accepted: 03/01/2012] [Indexed: 01/05/2023]
Abstract
Macroautophagy (autophagy) is a lysosomal degradation pathway that is conserved from yeast to humans that plays an important role in recycling cellular constituents in all cells. A number of protein complexes and signaling pathways impinge on the regulation of autophagy, with the mammalian target of rapamycin (mTOR) as the central player in the canonical pathway. Cytoplasmic Ca(2+) signaling also regulates autophagy, with both activating and inhibitory effects, mediated by the canonical as well as non-canonical pathways. Here we review this regulation, with a focus on the role of an mTOR-independent pathway that involves the inositol trisphosphate receptor (InsP(3)R) Ca(2+) release channel and Ca(2+) signaling to mitochondria. Constitutive InsP(3)R Ca(2+) transfer to mitochondria is required for autophagy suppression in cells in nutrient-replete media. In its absence, cells become metabolically compromised due to insufficient production of reducing equivalents to support oxidative phosphorylation. Absence of this Ca(2+) transfer to mitochondria results in activation of AMPK, which activates mTOR-independent pro-survival autophagy. Constitutive InsP(3)R Ca(2+) release to mitochondria is an essential cellular process that is required for efficient mitochondrial respiration, maintenance of normal cell bioenergetics and suppression of autophagy.
Collapse
|
36
|
Marimuthu M, Park C, Kim S, Choi CS. Real-time electrical measurement of L929 cellular spontaneous and synchronous oscillation. Int J Nanomedicine 2012; 7:83-92. [PMID: 22275825 PMCID: PMC3260953 DOI: 10.2147/ijn.s28465] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Indexed: 12/02/2022] Open
Abstract
Nonexcitable cell types, fibroblasts of heart muscle or astrocytes, are well known for their spontaneous Ca(2+) oscillations. On the other hand, murine fibroblast (L929) cells are known to be deficient in cell-cell adhesive proteins and therefore lack gap junctions for cellular communication. However, these cells exhibit a unique property of collectively synchronized and spontaneous oscillation, as revealed by real-time monitoring of cells cultured on a 250-μm diameter microelectrode for more than 3 days using an electrical cell-substrate impedance-sensing system (ECIS). Live-cell imaging is a widely used technique for oscillation detection, but it has limitations relating to cellular physiological environment maintenance for microscopic analysis and for prolonged periods of study. The present research emphasizes an electrical-sensing technique (ECIS) capable of overcoming the most important issues inherent in live-cell imaging systems for the detection of L929 cellular spontaneous and synchronized oscillation in real-time for longer periods. Possible mechanisms involved in L929 oscillation were elucidated to be periodic extension/contraction of lamellipodia continued as blebbing, which is produced by signals from the actomyosin complex initiated by connexin hemichannel opening and adenosine triphosphate (ATP) release. By applying the connexin hemichannel inhibitor, flufenamic acid, the hindrance of ATP release and calcium transients were analyzed to elucidate this hypothesis.
Collapse
Affiliation(s)
- Mohana Marimuthu
- College of Bionanotechnology, Kyungwon University, Seongnam-si, Gyeonggi-do, Republic of Korea
| | - Cheolsoo Park
- Department of Electrical and Electronic Engineering, Imperial College London, London, UK
| | - Sanghyo Kim
- College of Bionanotechnology, Kyungwon University, Seongnam-si, Gyeonggi-do, Republic of Korea
| | - Cheol Soo Choi
- Korea Mouse Metabolic Phenotyping Centre, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Yeonsu-gu, Incheon, Republic of Korea
| |
Collapse
|
37
|
Kakizawa S, Yamazawa T, Chen Y, Ito A, Murayama T, Oyamada H, Kurebayashi N, Sato O, Watanabe M, Mori N, Oguchi K, Sakurai T, Takeshima H, Saito N, Iino M. Nitric oxide-induced calcium release via ryanodine receptors regulates neuronal function. EMBO J 2011; 31:417-28. [PMID: 22036948 DOI: 10.1038/emboj.2011.386] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 09/28/2011] [Indexed: 12/13/2022] Open
Abstract
Mobilization of intracellular Ca(2+) stores regulates a multitude of cellular functions, but the role of intracellular Ca(2+) release via the ryanodine receptor (RyR) in the brain remains incompletely understood. We found that nitric oxide (NO) directly activates RyRs, which induce Ca(2+) release from intracellular stores of central neurons, and thereby promote prolonged Ca(2+) signalling in the brain. Reversible S-nitrosylation of type 1 RyR (RyR1) triggers this Ca(2+) release. NO-induced Ca(2+) release (NICR) is evoked by type 1 NO synthase-dependent NO production during neural firing, and is essential for cerebellar synaptic plasticity. NO production has also been implicated in pathological conditions including ischaemic brain injury, and our results suggest that NICR is involved in NO-induced neuronal cell death. These findings suggest that NICR via RyR1 plays a regulatory role in the physiological and pathophysiological functions of the brain.
Collapse
Affiliation(s)
- Sho Kakizawa
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Abstract
After central nervous system (CNS) injury axons fail to regenerate often leading to persistent neurologic deficit although injured peripheral nervous system (PNS) axons mount a robust regenerative response that may lead to functional recovery. Some of the failures of CNS regeneration arise from the many glial-based inhibitory molecules found in the injured CNS, whereas the intrinsic regenerative potential of some CNS neurons is actively curtailed during CNS maturation and limited after injury. In this review, the molecular basis for extrinsic and intrinsic modulation of axon regeneration within the nervous system is evaluated. A more complete understanding of the factors limiting axonal regeneration will provide a rational basis, which is used to develop improved treatments for nervous system injury.
Collapse
Affiliation(s)
- Toby A Ferguson
- Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | | |
Collapse
|
39
|
Okubo Y, Kanemaru K, Iino M. Imaging of Ca2+ and related signaling molecules and investigation of their functions in the brain. Antioxid Redox Signal 2011; 14:1303-14. [PMID: 20615120 DOI: 10.1089/ars.2010.3367] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Intracellular Ca(2+) signaling, and related mechanisms involving inositol 1,4,5-trisphosphate (IP(3)), nitric oxide, and the excitatory neurotransmitter glutamate, play a major role in the regulation of cellular function in the brain. Due to the complex morphology of central neurons, the correct spatiotemporal distribution of signaling molecules is essential. Thus, imaging studies have been particularly useful in elucidating the functions of these signaling molecules. The advancement of imaging methods, together with the development of a new method for the specific inhibition of intracellular IP(3) signaling, have made it possible to identify pathways that are regulated by Ca(2+) signals in the brain, including Ca(2+)-dependent synaptic maintenance and glial cell-dependent neurite growth. Further investigation of Ca(2+)-related signaling is expected to increase our understanding of brain function in the future.
Collapse
Affiliation(s)
- Yohei Okubo
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | | | | |
Collapse
|
40
|
Sobczak A, Debowska K, Blazejczyk M, Kreutz MR, Kuznicki J, Wojda U. Calmyrin1 binds to SCG10 protein (stathmin2) to modulate neurite outgrowth. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:1025-37. [PMID: 21215777 DOI: 10.1016/j.bbamcr.2010.12.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 12/21/2010] [Accepted: 12/28/2010] [Indexed: 02/03/2023]
Abstract
Calmyrin1 (CaMy1) is an EF-hand Ca(2+)-binding protein expressed in several cell types, including brain neurons. Using a yeast two-hybrid screen of a human fetal brain cDNA library, we identified SCG10 protein (stathmin2) as a CaMy1 partner. SCG10 is a microtubule-destabilizing factor involved in neuronal growth during brain development. We found increased mRNA and protein levels of CaMy1 during neuronal development, which paralleled the changes in SCG10 levels. In developing primary rat hippocampal neurons in culture, CaMy1 and SCG10 colocalized in cell soma, neurites, and growth cones. Pull-down, coimmunoprecipitation, and proximity ligation assays demonstrated that the interaction between CaMy1 and SCG10 is direct and Ca(2+)-dependent in vivo and requires the C-terminal domain of CaMy1 (residues 99-192) and the N-terminal domain of SCG10 (residues 1-35). CaMy1 did not interact with stathmin1, a protein that is homologous with SCG10 but lacks the N-terminal domain characteristic of SCG10. CaMy1 interfered with SCG10 inhibitory activity in a microtubule polymerization assay. Moreover, CaMy1 overexpression inhibited SCG10-mediated neurite outgrowth in nerve growth factor (NGF)-stimulated PC12 cells. This CaMy1 activity did not occur when an N-terminally truncated SCG10 mutant unable to interact with CaMy1 was expressed. Altogether, these data suggest that CaMy1 via SCG10 couples Ca(2+) signals with the dynamics of microtubules during neuronal outgrowth in the developing brain. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
Collapse
Affiliation(s)
- Adam Sobczak
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | | | | | | | | | | |
Collapse
|
41
|
A neurospheroid network-stamping method for neural transplantation to the brain. Biomaterials 2010; 31:8939-45. [DOI: 10.1016/j.biomaterials.2010.08.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 08/04/2010] [Indexed: 12/18/2022]
|
42
|
Changes in the content of GFAP in the rat brain during pregnancy and the beginning of lactation. Neurosci Lett 2010; 484:197-200. [DOI: 10.1016/j.neulet.2010.08.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 07/08/2010] [Accepted: 08/17/2010] [Indexed: 11/23/2022]
|
43
|
Mashimo M, Okubo Y, Yamazawa T, Yamasaki M, Watanabe M, Murayama T, Iino M. Inositol 1,4,5-trisphosphate signaling maintains the activity of glutamate uptake in Bergmann glia. Eur J Neurosci 2010; 32:1668-77. [PMID: 20958799 DOI: 10.1111/j.1460-9568.2010.07452.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The maintenance of synaptic functions is essential for neuronal information processing in the adult brain. Astrocytes express glutamate transporters that rapidly remove glutamate from the extracellular space and they play a critical role in the precise operation of glutamatergic transmission. However, how the glutamate clearance function of astrocytes is maintained remains elusive. Here, we describe a maintenance mechanism for the glutamate uptake capacity of Bergmann glial cells (BGs) in the cerebellum. When inositol 1,4,5-trisphosphate (IP(3) ) signaling was chronically and selectively inhibited in BGs in vivo, the retention time of glutamate around parallel fiber-Purkinje cell synapses was increased. Under these conditions, a decrease in the level of the glutamate/aspartate transporter (GLAST) in BGs was observed. The same effects were observed after chronic in vivo inhibition of purinergic P2 receptors in the cerebellar cortex. These results suggest that the IP(3) signaling cascade is involved in regulating GLAST levels in BGs to maintain glutamate clearance in the mature cerebellum.
Collapse
Affiliation(s)
- Masato Mashimo
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|
44
|
Morita M, Kudo Y. Growth factors upregulate astrocyte [Ca2+]i oscillation by increasing SERCA2b expression. Glia 2010; 58:1988-95. [DOI: 10.1002/glia.21067] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
45
|
Xie Y, Wang T, Sun GY, Ding S. Specific disruption of astrocytic Ca2+ signaling pathway in vivo by adeno-associated viral transduction. Neuroscience 2010; 170:992-1003. [PMID: 20736051 DOI: 10.1016/j.neuroscience.2010.08.034] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 08/16/2010] [Accepted: 08/18/2010] [Indexed: 10/19/2022]
Abstract
Astrocytes are the predominant glial-cell type in the CNS and they are known to play an active role in modulating neuronal function. Since many of the same molecules including G-protein coupled receptors (GPCRs) are expressed in both neurons and astrocytes, in vivo pharmacological manipulations to target astrocytes lack specificity. In this study, we investigated the effect of Pleckstrin Homology (PH) domain of Phospholipase C (PLC)-like protein p130 (p130PH) on Ca(2+) signaling in astrocytes in vivo. We used the serotype 2/5 recombinant adeno-associated virus (rAAV2/5) vectors to introduce p130PH fused with a tagged protein monomer red fluorescent protein at the N-terminal (i.e., transgene mRFP-p130PH). In order to selectively disrupt the Ca(2+) signaling pathway in astrocytes, the transgene was driven by a novel astrocyte-specific promoter gfaABC(1)D. Our results show that mRFP-p130PH is exclusively expressed in astrocytes with a high efficiency and a stable expression level. In vivo imaging using two-photon microscopy demonstrated reduced Ca(2+) signal in transduced astrocytes in response to ATP stimulation. As Ca(2+) signaling is a characteristic form of cellular excitability in astrocytes that can mediate chemical transmitter release and contribute to neuronal excitotoxicity, the current study provides an in vivo approach to better understand Ca(2+)-dependent gliotransmission and its involvement in glia-related diseases.
Collapse
Affiliation(s)
- Y Xie
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, MO 65211, USA
| | | | | | | |
Collapse
|
46
|
Zeng S, Li B, Zeng S, Chen S. Simulation of spontaneous Ca2+ oscillations in astrocytes mediated by voltage-gated calcium channels. Biophys J 2010; 97:2429-37. [PMID: 19883585 DOI: 10.1016/j.bpj.2009.08.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2008] [Revised: 08/10/2009] [Accepted: 08/11/2009] [Indexed: 11/15/2022] Open
Abstract
The purpose of this computational study was to investigate the possible role of voltage-gated Ca(2+) channels in spontaneous Ca(2+) oscillations of astrocytes. By incorporating different types of voltage-gated Ca(2+) channels and a previous model, this study reproduced typical Ca(2+) oscillations in silico. Our model could mimic the oscillatory phenomenon under a wide range of experimental conditions, including resting membrane potential (-75 to -60 mV), extracellular Ca(2+) concentration (0.1 to 1500 muM), temperature (20 to 37 degrees C), and blocking specific Ca(2+) channels. By varying the experimental conditions, the amplitude and duration of Ca(2+) oscillations changed slightly (both <25%), while the frequency changed significantly ( approximately 400%). This indicates that spontaneous Ca(2+) oscillations in astrocytes might be an all-or-none process, which might be frequency-encoded in signaling. Moreover, the properties of Ca(2+) oscillations were found to be related to the dynamics of Ca(2+) influx, and not only to a constant influx. Therefore, calcium channels dynamics should be used in studying Ca(2+) oscillations. This work provides a platform to explore the still unclear mechanism of spontaneous Ca(2+) oscillations in astrocytes.
Collapse
Affiliation(s)
- Shuai Zeng
- Britton Chance Center of Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China
| | | | | | | |
Collapse
|
47
|
Petralia RS, Wang YX, Hua F, Yi Z, Zhou A, Ge L, Stephenson FA, Wenthold RJ. Organization of NMDA receptors at extrasynaptic locations. Neuroscience 2010; 167:68-87. [PMID: 20096331 DOI: 10.1016/j.neuroscience.2010.01.022] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 12/14/2009] [Accepted: 01/13/2010] [Indexed: 12/14/2022]
Abstract
NMDA receptors are found in neurons both at synapses and in extrasynaptic locations. Extrasynaptic locations are poorly characterized. Here we used preembedding immunoperoxidase and postembedding immunogold electron microscopy and fluorescence light microscopy to characterize extrasynaptic NMDA receptor locations in dissociated hippocampal neurons in vitro and in the adult and postnatal hippocampus in vivo. We found that extrasynaptic NMDA receptors on neurons in vivo and in vitro were usually concentrated at points of contact with adjacent processes, which were mainly axons, axon terminals, or glia. Many of these contacts were shown to contain adhesion factors such as cadherin and catenin. We also found associations of extrasynaptic NMDA receptors with the membrane associated guanylate kinase (MAGUKs), postsynaptic density (PSD)-95 and SAP102. Developmental differences were also observed. At postnatal day 2 in vivo, extrasynaptic NMDA receptors could often be found at sites with distinct densities whereas dense material was seen only rarely at sites of extrasynaptic NMDA receptors in the adult hippocampus in vivo. This difference probably indicates that many sites of extrasynaptic NMDA receptors in early postnatal ages represent synapse formation or possibly sites for synapse elimination. At all ages, as suggested in both in vivo and in vitro studies, extrasynaptic NMDA receptors on dendrites or the sides of spines may form complexes with other proteins, in many cases, at stable associations with adjacent cell processes. These associations may facilitate unique functions for extrasynaptic NMDA receptors.
Collapse
Affiliation(s)
- R S Petralia
- Laboratory of Neurochemistry, National Institute on Deafness and Other Communication Disorders/National Institutes of Health (NIDCD/NIH), Bethesda, MD, USA.
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Iino M. Spatiotemporal dynamics of Ca2+ signaling and its physiological roles. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2010; 86:244-256. [PMID: 20228624 PMCID: PMC3417849 DOI: 10.2183/pjab.86.244] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 02/15/2010] [Indexed: 05/28/2023]
Abstract
Changes in the intracellular Ca(2+) concentration regulate numerous cell functions and display diverse spatiotemporal dynamics, which underlie the versatility of Ca(2+) in cell signaling. In many cell types, an increase in the intracellular Ca(2+) concentration starts locally, propagates within the cell (Ca(2+) wave) and makes oscillatory changes (Ca(2+) oscillation). Studies of the intracellular Ca(2+) release mechanism from the endoplasmic reticulum (ER) showed that the Ca(2+) release mechanism has inherent regenerative properties, which is essential for the generation of Ca(2+) waves and oscillations. Ca(2+) may shuttle between the ER and mitochondria, and this appears to be important for pacemaking of Ca(2+) oscillations. Importantly, Ca(2+) oscillations are an efficient mechanism in regulating cell functions, having effects supra-proportional to the sum of duration of Ca(2+) increase. Furthermore, Ca(2+) signaling mechanism studies have led to the development of a method for specific inhibition of Ca(2+) signaling, which has been used to identify hitherto unrecognized functions of Ca(2+) signals.
Collapse
Affiliation(s)
- Masamitsu Iino
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
| |
Collapse
|
49
|
Abstract
Radial glia in the developing optic tectum express the key guidance molecules responsible for topographic targeting of retinal axons. However, the extent to which the radial glia are themselves influenced by retinal inputs and visual experience remains unknown. Using multiphoton live imaging of radial glia in the optic tectum of intact Xenopus laevis tadpoles in conjunction with manipulations of neural activity and sensory stimuli, radial glia were observed to exhibit spontaneous calcium transients that were modulated by visual stimulation. Structurally, radial glia extended and retracted many filopodial processes within the tectal neuropil over minutes. These processes interacted with retinotectal synapses and their motility was modulated by nitric oxide (NO) signaling downstream of neuronal NMDA receptor (NMDAR) activation and visual stimulation. These findings provide the first in vivo demonstration that radial glia actively respond both structurally and functionally to neural activity, via NMDAR-dependent NO release during the period of retinal axon ingrowth.
Collapse
|
50
|
Role of glial cells in the formation and maintenance of synapses. ACTA ACUST UNITED AC 2009; 63:39-46. [PMID: 19931561 DOI: 10.1016/j.brainresrev.2009.11.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 11/06/2009] [Accepted: 11/11/2009] [Indexed: 11/23/2022]
Abstract
Synaptogenesis is a decisive process for the development of the brain, its plasticity during adulthood and its regeneration after injury and disease. Despite tremendous progress during the last decades, it remains unclear, whether neurons can form synapses autonomously. In this review, I will summarize recent evidence that this is probably not the case and that distinct phases of synapse development depend on help from glial cells. The results supporting this view come from studies on the central and peripheral nervous system and on different experimental models including cultured cells as well as living flies, worms and mice. Our understanding of synapse-glia interactions in the developing, adult and diseased brain is likely to advance more rapidly as new experimental approaches to identify, visualize and manipulate glial cells in vivo become available.
Collapse
|