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Li JT, Jin SY, Hu J, Xu RX, Xu JN, Li ZM, Wang ML, Fu YW, Liao SH, Li XW, Chen YH, Gao TM, Yang JM. Astrocytes in the Ventral Hippocampus Bidirectionally Regulate Innate and Stress-Induced Anxiety-Like Behaviors in Male Mice. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2400354. [PMID: 39120568 DOI: 10.1002/advs.202400354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 07/29/2024] [Indexed: 08/10/2024]
Abstract
The mechanisms of anxiety disorders, the most common mental illness, remain incompletely characterized. The ventral hippocampus (vHPC) is critical for the expression of anxiety. However, current studies primarily focus on vHPC neurons, leaving the role for vHPC astrocytes in anxiety largely unexplored. Here, genetically encoded Ca2+ indicator GCaMP6m and in vivo fiber photometry calcium imaging are used to label vHPC astrocytes and monitor their activity, respectively, genetic and chemogenetic approaches to inhibit and activate vHPC astrocytes, respectively, patch-clamp recordings to measure glutamate currents, and behavioral assays to assess anxiety-like behaviors. It is found that vHPC astrocytic activity is increased in anxiogenic environments and by 3-d subacute restraint stress (SRS), a well-validated mouse model of anxiety disorders. Genetic inhibition of vHPC astrocytes exerts anxiolytic effects on both innate and SRS-induced anxiety-related behaviors, whereas hM3Dq-mediated chemogenetic or SRS-induced activation of vHPC astrocytes enhances anxiety-like behaviors, which are reversed by intra-vHPC application of the ionotropic glutamate N-methyl-d-aspartate receptor antagonists. Furthermore, intra-vHPC or systemic application of the N-methyl-d-aspartate receptor antagonist memantine, a U.S. FDA-approved drug for Alzheimer's disease, fully rescues SRS-induced anxiety-like behaviors. The findings highlight vHPC astrocytes as critical regulators of stress and anxiety and as potential therapeutic targets for anxiety and anxiety-related disorders.
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Affiliation(s)
- Jing-Ting Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Shi-Yang Jin
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Jian Hu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Ru-Xia Xu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Jun-Nan Xu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Zi-Ming Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Meng-Ling Wang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Yi-Wen Fu
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Shi-Han Liao
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Xiao-Wen Li
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Yi-Hua Chen
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Tian-Ming Gao
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Jian-Ming Yang
- State Key Laboratory of Organ Failure Research, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
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2
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Kosenkov AM, Maiorov SA, Gaidin SG. Astrocytic NMDA Receptors. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:1045-1060. [PMID: 38981700 DOI: 10.1134/s0006297924060063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 07/11/2024]
Abstract
Astrocytic NMDA receptors (NMDARs) are heterotetramers, whose expression and properties are largely determined by their subunit composition. Astrocytic NMDARs are characterized by a low sensitivity to magnesium ions and low calcium conductivity. Their activation plays an important role in the regulation of various intracellular processes, such as gene expression and mitochondrial function. Astrocytic NMDARs are involved in calcium signaling in astrocytes and can act through the ionotropic and metabotropic pathways. Astrocytic NMDARs participate in the interactions of the neuroglia, thus affecting synaptic plasticity. They are also engaged in the astrocyte-vascular interactions and contribute to the regulation of vascular tone. Astrocytic NMDARs are involved in various pathologies, such as ischemia and hyperammonemia, and their blockade prevents negative changes in astrocytes during these diseases.
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Affiliation(s)
- Artem M Kosenkov
- Pushchino Scientific Center for Biological Research, Institute of Cell Biophysics of the Russian Academy of Sciences, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
| | - Sergei A Maiorov
- Pushchino Scientific Center for Biological Research, Institute of Cell Biophysics of the Russian Academy of Sciences, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
| | - Sergei G Gaidin
- Pushchino Scientific Center for Biological Research, Institute of Cell Biophysics of the Russian Academy of Sciences, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
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3
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Yang XM, Yu H, Li JX, Li N, Li C, Xu DH, Zhang H, Fang TH, Wang SJ, Yan PY, Han BB. Excitotoxic Storms of Ischemic Stroke: A Non-neuronal Perspective. Mol Neurobiol 2024:10.1007/s12035-024-04184-7. [PMID: 38662299 DOI: 10.1007/s12035-024-04184-7] [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: 11/26/2023] [Accepted: 04/15/2024] [Indexed: 04/26/2024]
Abstract
Numerous neurological disorders share a fatal pathologic process known as glutamate excitotoxicity. Among which, ischemic stroke is the major cause of mortality and disability worldwide. For a long time, the main idea of developing anti-excitotoxic neuroprotective agents was to block glutamate receptors. Despite this, there has been little successful clinical translation to date. After decades of "neuron-centered" views, a growing number of studies have recently revealed the importance of non-neuronal cells. Glial cells, cerebral microvascular endothelial cells, blood cells, and so forth are extensively engaged in glutamate synthesis, release, reuptake, and metabolism. They also express functional glutamate receptors and can listen and respond for fast synaptic transmission. This broadens the thoughts of developing excitotoxicity antagonists. In this review, the critical contribution of non-neuronal cells in glutamate excitotoxicity during ischemic stroke will be emphasized in detail, and the latest research progress as well as corresponding therapeutic strategies will be updated at length, aiming to reconceptualize glutamate excitotoxicity in a non-neuronal perspective.
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Affiliation(s)
- Xiao-Man Yang
- Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, People's Republic of China
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China
| | - Hao Yu
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China
| | - Jia-Xin Li
- Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, People's Republic of China
| | - Na Li
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China
| | - Chong Li
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China
| | - Dong-Han Xu
- Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, People's Republic of China
| | - Hao Zhang
- Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, People's Republic of China
| | - Tian-He Fang
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China
| | - Shi-Jun Wang
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China.
| | - Pei-Yu Yan
- Faculty of Chinese Medicine, Macau University of Science and Technology, Macau, People's Republic of China.
- State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau, People's Republic of China.
- Zhuhai MUST Science and Technology Research Institute, Macau University of Science and Technology, Macau, People's Republic of China.
| | - Bing-Bing Han
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, People's Republic of China.
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4
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Fan Y, Huang H, Shao J, Huang W. MicroRNA-mediated regulation of reactive astrocytes in central nervous system diseases. Front Mol Neurosci 2023; 15:1061343. [PMID: 36710937 PMCID: PMC9877358 DOI: 10.3389/fnmol.2022.1061343] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 12/22/2022] [Indexed: 01/15/2023] Open
Abstract
Astrocytes (AST) are abundant glial cells in the human brain, accounting for approximately 20-50% percent of mammalian central nervous system (CNS) cells. They display essential functions necessary to sustain the physiological processes of the CNS, including maintaining neuronal structure, forming the blood-brain barrier, coordinating neuronal metabolism, maintaining the extracellular environment, regulating cerebral blood flow, stabilizing intercellular communication, participating in neurotransmitter synthesis, and defending against oxidative stress et al. During the pathological development of brain tumors, stroke, spinal cord injury (SCI), neurodegenerative diseases, and other neurological disorders, astrocytes undergo a series of highly heterogeneous changes, which are called reactive astrocytes, and mediate the corresponding pathophysiological process. However, the pathophysiological mechanisms of reactive astrocytes and their therapeutic relevance remain unclear. The microRNAs (miRNAs) are essential for cell differentiation, proliferation, and survival, which play a crucial role in the pathophysiological development of CNS diseases. In this review, we summarize the regulatory mechanism of miRNAs on reactive astrocytes in CNS diseases, which might provide a theoretical basis for the diagnosis and treatment of CNS diseases.
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5
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Turgutalp B, Bhattarai P, Ercetin T, Luise C, Reis R, Gurdal EE, Isaak A, Biriken D, Dinter E, Sipahi H, Schepmann D, Junker A, Wünsch B, Sippl W, Gulcan HO, Kizil C, Yarim M. Discovery of Potent Cholinesterase Inhibition-Based Multi-Target-Directed Lead Compounds for Synaptoprotection in Alzheimer's Disease. J Med Chem 2022; 65:12292-12318. [PMID: 36084304 DOI: 10.1021/acs.jmedchem.2c01003] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Drug development efforts that focused on single targets failed to provide effective treatment for Alzheimer's disease (AD). Therefore, we designed cholinesterase inhibition (ChEI)-based multi-target-directed ligands (MTDLs) to simultaneously target AD-related receptors. We built a library of 70 compounds, sequentially screened for ChEI, and determined σ1R, σ2R, NMDAR-GluN2B binding affinities, and P2X7R antagonistic activities. Nine fulfilled in silico drug-likeness criteria and did not display toxicity in three cell lines. Seven displayed cytoprotective activity in two stress-induced cellular models. Compared to donepezil, six showed equal/better synaptic protection in a zebrafish model of acute amyloidosis-induced synaptic degeneration. Two P2X7R antagonists alleviated the activation state of microglia in vivo. Permeability studies were performed, and four did not inhibit CYP450 3A4, 2D6, and 2C9. Therefore, four ChEI-based lead MTDLs are promising drug candidates for synaptic integrity protection and could serve as disease-modifying AD treatment. Our study also proposes zebrafish as a useful preclinical tool for drug discovery and development.
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Affiliation(s)
- Bengisu Turgutalp
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Yeditepe University, 34755 Istanbul, Turkey.,German Centre for Neurodegenerative Diseases (DZNE), Helmholtz Association, 01307 Dresden, Germany
| | - Prabesh Bhattarai
- German Centre for Neurodegenerative Diseases (DZNE), Helmholtz Association, 01307 Dresden, Germany.,Department of Neurology, Columbia University Irving Medical Center, 10032 New York, United States
| | - Tugba Ercetin
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Eastern Mediterranean University, TRNC, via Mersin 10, 99628 Famagusta, Turkey
| | - Chiara Luise
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, 6099 Halle (Saale), Germany
| | - Rengin Reis
- Department of Toxicology, Faculty of Pharmacy, Yeditepe University, 34755 Istanbul, Turkey.,Department of Toxicology, Faculty of Pharmacy, Acibadem Mehmet Ali Aydinlar University, 34758 Istanbul, Turkey
| | - Enise Ece Gurdal
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Yeditepe University, 34755 Istanbul, Turkey.,Institute of Chemistry, Martin-Luther-Universität Halle-Wittenberg, 06120 Halle, Germany
| | - Andreas Isaak
- European Institute for Molecular Imaging (EIMI), der Westfälischen Wilhelms-Universität, D-48149 Münster, Germany
| | - Derya Biriken
- German Centre for Neurodegenerative Diseases (DZNE), Helmholtz Association, 01307 Dresden, Germany.,Department of Medical Microbiology, Ankara University Faculty of Medicine, 06620 Ankara, Turkey
| | - Elisabeth Dinter
- German Centre for Neurodegenerative Diseases (DZNE), Helmholtz Association, 01307 Dresden, Germany.,Department of Neurology, University Clinic, TU Dresden, 01307 Dresden, Germany
| | - Hande Sipahi
- Department of Toxicology, Faculty of Pharmacy, Yeditepe University, 34755 Istanbul, Turkey
| | - Dirk Schepmann
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, D-48149 Münster, Germany
| | - Anna Junker
- European Institute for Molecular Imaging (EIMI), der Westfälischen Wilhelms-Universität, D-48149 Münster, Germany
| | - Bernhard Wünsch
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, D-48149 Münster, Germany
| | - Wolfgang Sippl
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, 6099 Halle (Saale), Germany
| | - Hayrettin Ozan Gulcan
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Eastern Mediterranean University, TRNC, via Mersin 10, 99628 Famagusta, Turkey
| | - Caghan Kizil
- German Centre for Neurodegenerative Diseases (DZNE), Helmholtz Association, 01307 Dresden, Germany.,Department of Neurology, Columbia University Irving Medical Center, 10032 New York, United States
| | - Mine Yarim
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Yeditepe University, 34755 Istanbul, Turkey
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Hastings N, Kuan WL, Osborne A, Kotter MRN. Therapeutic Potential of Astrocyte Transplantation. Cell Transplant 2022; 31:9636897221105499. [PMID: 35770772 PMCID: PMC9251977 DOI: 10.1177/09636897221105499] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cell transplantation is an attractive treatment strategy for a variety of brain disorders, as it promises to replenish lost functions and rejuvenate the brain. In particular, transplantation of astrocytes has come into light recently as a therapy for amyotrophic lateral sclerosis (ALS); moreover, grafting of astrocytes also showed positive results in models of other conditions ranging from neurodegenerative diseases of older age to traumatic injury and stroke. Despite clear differences in etiology, disorders such as ALS, Parkinson's, Alzheimer's, and Huntington's diseases, as well as traumatic injury and stroke, converge on a number of underlying astrocytic abnormalities, which include inflammatory changes, mitochondrial damage, calcium signaling disturbance, hemichannel opening, and loss of glutamate transporters. In this review, we examine these convergent pathways leading to astrocyte dysfunction, and explore the existing evidence for a therapeutic potential of transplantation of healthy astrocytes in various models. Existing literature presents a wide variety of methods to generate astrocytes, or relevant precursor cells, for subsequent transplantation, while described outcomes of this type of treatment also differ between studies. We take technical differences between methodologies into account to understand the variability of therapeutic benefits, or lack thereof, at a deeper level. We conclude by discussing some key requirements of an astrocyte graft that would be most suitable for clinical applications.
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Affiliation(s)
- Nataly Hastings
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Wei-Li Kuan
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Andrew Osborne
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Mark R N Kotter
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
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7
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Chipman PH, Fung CCA, Pazo Fernandez A, Sawant A, Tedoldi A, Kawai A, Ghimire Gautam S, Kurosawa M, Abe M, Sakimura K, Fukai T, Goda Y. Astrocyte GluN2C NMDA receptors control basal synaptic strengths of hippocampal CA1 pyramidal neurons in the stratum radiatum. eLife 2021; 10:70818. [PMID: 34693906 PMCID: PMC8594917 DOI: 10.7554/elife.70818] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 10/22/2021] [Indexed: 12/12/2022] Open
Abstract
Experience-dependent plasticity is a key feature of brain synapses for which neuronal N-Methyl-D-Aspartate receptors (NMDARs) play a major role, from developmental circuit refinement to learning and memory. Astrocytes also express NMDARs, although their exact function has remained controversial. Here, we identify in mouse hippocampus, a circuit function for GluN2C NMDAR, a subtype highly expressed in astrocytes, in layer-specific tuning of synaptic strengths in CA1 pyramidal neurons. Interfering with astrocyte NMDAR or GluN2C NMDAR activity reduces the range of presynaptic strength distribution specifically in the stratum radiatum inputs without an appreciable change in the mean presynaptic strength. Mathematical modeling shows that narrowing of the width of presynaptic release probability distribution compromises the expression of long-term synaptic plasticity. Our findings suggest a novel feedback signaling system that uses astrocyte GluN2C NMDARs to adjust basal synaptic weight distribution of Schaffer collateral inputs, which in turn impacts computations performed by the CA1 pyramidal neuron.
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Affiliation(s)
| | - Chi Chung Alan Fung
- Neural Coding and Brain Computing Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Japan
| | | | | | - Angelo Tedoldi
- RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | - Atsushi Kawai
- RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | | | | | - Manabu Abe
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Kenji Sakimura
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Tomoki Fukai
- Neural Coding and Brain Computing Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Japan
| | - Yukiko Goda
- RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
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8
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Tilianin Ameliorates Cognitive Dysfunction and Neuronal Damage in Rats with Vascular Dementia via p-CaMKII/ERK/CREB and ox-CaMKII-Dependent MAPK/NF- κB Pathways. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6673967. [PMID: 34527176 PMCID: PMC8437593 DOI: 10.1155/2021/6673967] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 08/09/2021] [Accepted: 08/11/2021] [Indexed: 12/13/2022]
Abstract
Vascular dementia (VaD) is a common cause of cognitive decline and dementia of vascular origin, but the precise pathological mechanisms are unknown, and so effective clinical treatments have not been established. Tilianin, the principal active compound of total flavonoid extract from Dracocephalum moldavica L., is a candidate therapy for cardio-cerebrovascular diseases in China. However, its potential in the treatment of VaD is unclear. The present study is aimed at investigating the protective effects of tilianin on VaD and exploring the underlying mechanism of the action. A model of VaD was established by permanent 2-vessel occlusion (2VO) in rats. Human neurons (hNCs) differentiated from human-induced pluripotent stem cells were used to establish an oxygen-glucose deprivation (OGD) model. The therapeutic effects and potential mechanisms of tilianin were identified using behavioral tests, histochemistry, and multiple molecular biology techniques such as Western blot analysis and gene silencing. The results demonstrated that tilianin modified spatial cognitive impairment, neurodegeneration, oxidation, and apoptosis in rats with VaD and protected hNCs against OGD by increasing cell viability and decreasing apoptosis rates. A study of the mechanism indicated that tilianin restored p-CaMKII/ERK1/2/CREB signaling in the hippocampus, maintaining hippocampus-independent memory. In addition, tilianin inhibited an ox-CaMKII/p38 MAPK/JNK/NF-κB associated inflammatory response caused by cerebral oxidative stress imbalance in rats with VaD. Furthermore, specific CaMKIIα siRNA action revealed that tilianin-exerted neuroprotection involved increase of neuronal viability, inhibition of apoptosis, and suppression of inflammation, which was dependent on CaMKIIα. In conclusion, the results suggested the neuroprotective effect of tilianin in VaD and the potential mechanism associated with dysfunction in the regulation of p-CaMKII-mediated long-term memory and oxidation and inflammation involved with ox-CaMKII, which may lay the foundation for clinical trials of tilianin for the treatment of VaD in the future.
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9
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Belov Kirdajova D, Kriska J, Tureckova J, Anderova M. Ischemia-Triggered Glutamate Excitotoxicity From the Perspective of Glial Cells. Front Cell Neurosci 2020; 14:51. [PMID: 32265656 PMCID: PMC7098326 DOI: 10.3389/fncel.2020.00051] [Citation(s) in RCA: 185] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/21/2020] [Indexed: 12/21/2022] Open
Abstract
A plethora of neurological disorders shares a final common deadly pathway known as excitotoxicity. Among these disorders, ischemic injury is a prominent cause of death and disability worldwide. Brain ischemia stems from cardiac arrest or stroke, both responsible for insufficient blood supply to the brain parenchyma. Glucose and oxygen deficiency disrupts oxidative phosphorylation, which results in energy depletion and ionic imbalance, followed by cell membrane depolarization, calcium (Ca2+) overload, and extracellular accumulation of excitatory amino acid glutamate. If tight physiological regulation fails to clear the surplus of this neurotransmitter, subsequent prolonged activation of glutamate receptors forms a vicious circle between elevated concentrations of intracellular Ca2+ ions and aberrant glutamate release, aggravating the effect of this ischemic pathway. The activation of downstream Ca2+-dependent enzymes has a catastrophic impact on nervous tissue leading to cell death, accompanied by the formation of free radicals, edema, and inflammation. After decades of “neuron-centric” approaches, recent research has also finally shed some light on the role of glial cells in neurological diseases. It is becoming more and more evident that neurons and glia depend on each other. Neuronal cells, astrocytes, microglia, NG2 glia, and oligodendrocytes all have their roles in what is known as glutamate excitotoxicity. However, who is the main contributor to the ischemic pathway, and who is the unsuspecting victim? In this review article, we summarize the so-far-revealed roles of cells in the central nervous system, with particular attention to glial cells in ischemia-induced glutamate excitotoxicity, its origins, and consequences.
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Affiliation(s)
- Denisa Belov Kirdajova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic (ASCR), Prague, Czechia.,Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Jan Kriska
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic (ASCR), Prague, Czechia.,Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Jana Tureckova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic (ASCR), Prague, Czechia
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic (ASCR), Prague, Czechia.,Second Faculty of Medicine, Charles University, Prague, Czechia
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10
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Denver P, D’Adamo H, Hu S, Zuo X, Zhu C, Okuma C, Kim P, Castro D, Jones MR, Leal C, Mekkittikul M, Ghadishah E, Teter B, Vinters HV, Cole GM, Frautschy SA. A Novel Model of Mixed Vascular Dementia Incorporating Hypertension in a Rat Model of Alzheimer's Disease. Front Physiol 2019; 10:1269. [PMID: 31708792 PMCID: PMC6821690 DOI: 10.3389/fphys.2019.01269] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 09/19/2019] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) and mixed dementia (MxD) comprise the majority of dementia cases in the growing global aging population. MxD describes the coexistence of AD pathology with vascular pathology, including cerebral small vessel disease (SVD). Cardiovascular disease increases risk for AD and MxD, but mechanistic synergisms between the coexisting pathologies affecting dementia risk, progression and the ultimate clinical manifestations remain elusive. To explore the additive or synergistic interactions between AD and chronic hypertension, we developed a rat model of MxD, produced by breeding APPswe/PS1ΔE9 transgenes into the stroke-prone spontaneously hypertensive rat (SHRSP) background, resulting in the SHRSP/FAD model and three control groups (FAD, SHRSP and non-hypertensive WKY rats, n = 8-11, both sexes, 16-18 months of age). After behavioral testing, rats were euthanized, and tissue assessed for vascular, neuroinflammatory and AD pathology. Hypertension was preserved in the SHRSP/FAD cross. Results showed that SHRSP increased FAD-dependent neuroinflammation (microglia and astrocytes) and tau pathology, but plaque pathology changes were subtle, including fewer plaques with compact cores and slightly reduced plaque burden. Evidence for vascular pathology included a change in the distribution of astrocytic end-foot protein aquaporin-4, normally distributed in microvessels, but in SHRSP/FAD rats largely dissociated from vessels, appearing disorganized or redistributed into neuropil. Other evidence of SVD-like pathology included increased collagen IV staining in cerebral vessels and PECAM1 levels. We identified a plasma biomarker in SHRSP/FAD rats that was the only group to show increased Aqp-4 in plasma exosomes. Evidence of neuron damage in SHRSP/FAD rats included increased caspase-cleaved actin, loss of myelin and reduced calbindin staining in neurons. Further, there were mitochondrial deficits specific to SHRSP/FAD, notably the loss of complex II, accompanying FAD-dependent loss of mitochondrial complex I. Cognitive deficits exhibited by FAD rats were not exacerbated by the introduction of the SHRSP phenotype, nor was the hyperactivity phenotype associated with SHRSP altered by the FAD transgene. This novel rat model of MxD, encompassing an amyloidogenic transgene with a hypertensive phenotype, exhibits several features associated with human vascular or "mixed" dementia and may be a useful tool in delineating the pathophysiology of MxD and development of therapeutics.
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Affiliation(s)
- Paul Denver
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Heather D’Adamo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Shuxin Hu
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Xiaohong Zuo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Cansheng Zhu
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Chihiro Okuma
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Peter Kim
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Daniel Castro
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Mychica R. Jones
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Carmen Leal
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Marisa Mekkittikul
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Elham Ghadishah
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Bruce Teter
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Harry V. Vinters
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Gregory Michael Cole
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Sally A. Frautschy
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
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11
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Zamberlam CR, Tilger MAS, Moraes L, Cerutti JM, Cerutti SM. Ginkgo biloba treatments reverse the impairment of conditioned suppression acquisition induced by GluN2B-NMDA and 5-HT 1A receptor blockade: Modulatory effects of the circuitry of the dorsal hippocampal formation. Physiol Behav 2019; 209:112534. [PMID: 31071338 DOI: 10.1016/j.physbeh.2019.04.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/29/2019] [Accepted: 04/26/2019] [Indexed: 01/09/2023]
Abstract
To improve our understanding of the effects of standardized extract of Ginkgo biloba (EGb) as a cognitive enhancer, we investigated the conditioned lick suppression-induced expression (mRNA and protein) of the GluN2B-containing N-methyl-D-aspartic acid receptor (GluN2B-NMDAR), serotonin (5-HT) 1A receptor (5-HT1AR), gamma-aminobutyric acid type A receptor (GABAAR) and glial fibrillary acidic protein (GFAP) in the dorsal hippocampal formation (dHF) of untreated and EGb-treated (0.25, 0.5 and 1.0 g.kg-1) groups of rats. To substantiate our data, we analysed the molecular changes in dHF following treatment with vehicle, with agonists or antagonists of GABAAR, GluN2B-NMDAR and 5-HT1AR or with one of these antagonists prior to EGb and fear memory acquisition. Additionally, we performed a pharmacological analysis of the drug-receptor-receptor interactions and their supplemental role in fear memory by blocking individual receptors and analysed the possible changes in expression level with each of the other receptors in the study as well as astrocytes. Our data show for the first time that EGb treatment not only upregulated GluN2B, GABAAR-α5, and GFAP compared with the control but also differentially upregulated GABAAR-α1 in the dHF and 5HT1AR in the CA3. We found that the activation of GABAARs (diazepam) and the inactivation of GluN2B-NMDARs (Ro25-6981) or 5-HT1AR ((S)-WAY100135) resulted in memory impairment. Further, higher doses of EGb treatment reversed the effect of blocking GluN2B (P < 0.001) and 5-HT1AR (P < 0.001). Here, treatment with Ro25-6981 + EGb or (S)-WAY100135 + EGb prevented the impairment of the acquisition of lick suppression in association with the upregulation or prevention of the downregulation of Grin2b expression as well as the expression of GluN2B-NMDA and/or α1 and α5 subunit-containing GABAAR in the CA1 (P < 0.0001). Our data are in line with previous findings concerning the necessity of GluN2B for fear memory formation and add to the current knowledge of the role of the GABAAR-α1 and -α5 subunits and of GluN2B as a target of cognitive enhancers. Furthermore, our data show that these receptors play a complementary role in controlling the neural circuitry in the dHF that seems to be essential to conditioned lick suppression and the modulatory effects of EGb.
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Affiliation(s)
- Cláudia R Zamberlam
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil; Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Myrcea A S Tilger
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil
| | - Laís Moraes
- Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Janete M Cerutti
- Universidade Federal de São Paulo, Departamento de Morfologia e Genética, Laboratório Bases Genéticas do Tumor da Tiróide, São Paulo, SP, Brazil
| | - Suzete M Cerutti
- Universidade Federal de São Paulo. Departamento de Ciências Biológicas. Laboratório de Farmacologia Celular e Comportamental, Diadema, SP, Brazil.
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12
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Zhang X, Li X, Liu N, Zheng P, Ma L, Guo F, Sun T, Zhou R, Yu J. The Anticonvulsant Effects of Baldrinal on Pilocarpine-Induced convulsion in Adult Male Mice. Molecules 2019; 24:E1617. [PMID: 31022879 PMCID: PMC6514916 DOI: 10.3390/molecules24081617] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 04/19/2019] [Accepted: 04/20/2019] [Indexed: 02/07/2023] Open
Abstract
Epilepsy is a prevalent neurological disorder that was reported to affect about 56 million people in the world. Approximately one-third of the epileptic patients that suffer from seizures do not receive effective medical treatment. The aim of this study was to determine the potential anticonvulsant activities of Baldrinal (BAL) with a mouse model of pilocarpine (PILO)-induced epilepsy. The mice were treated with different doses of BAL or sodium valproate prior to PILO injection. Spontaneous and evoked seizures were evaluated from EEG recordings, and their severity was tested by the Racine scale. In addition, the brain tissues were analyzed for histological changes, and the in situ levels of glutamic acid (Glu) and gamma-aminobutyric acid (GABA) were also measured. Activation of astrocytes in the hippocampus was measured. PILO-treated mice showed a significant increase in Glu levels, which was restored by BAL. In addition, BAL treatment also reduced the rate of seizures in the epileptic mice, and ameliorated the increased levels of NMDAR1, BDNF, IL-1β and TNF-α. Taken together, BAL has a potential antiepileptic effect, which may be mediated by reducing the inflammatory response in the PILO-induced brain and restoring the balance of GABAergic and glutamatergic neurons.
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Affiliation(s)
- Xiao Zhang
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
| | - Xing Li
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
| | - Ning Liu
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
| | - Ping Zheng
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
| | - Lin Ma
- Ningxia Key Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan 750004, China.
| | - Fengying Guo
- College of Basic Medicine, Ningxia Medical University, Yinchuan 750004, China.
| | - Tao Sun
- Ningxia Key Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan 750004, China.
| | - Ru Zhou
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
| | - Jianqiang Yu
- Department of Pharmacology, Ningxia Medical University, Yinchuan 750004, China.
- Ningxia Hui Medicine Modern Engineering Research Center and Collaborative Innovation Center, Ningxia Medical University, Yinchuan 750004, China.
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13
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Sadick JS, Liddelow SA. Don't forget astrocytes when targeting Alzheimer's disease. Br J Pharmacol 2019; 176:3585-3598. [PMID: 30636042 DOI: 10.1111/bph.14568] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/13/2018] [Accepted: 11/19/2018] [Indexed: 12/25/2022] Open
Abstract
Astrocytes are essential for CNS health, regulating homeostasis, metabolism, and synaptic transmission. In addition to these and many other physiological roles, the pathological impact of astrocytes ("reactive astrocytes") in acute trauma and chronic disease like Alzheimer's disease (AD) is well established. Growing evidence supports a fundamental and active role of astrocytes in multiple neurodegenerative diseases. With a growing interest in normal astrocyte biology, and countless studies on changes in astrocyte function in the context of disease, it may be a surprise that no therapies exist incorporating astrocytes as key targets. Here, we examine unintentional effects of current AD therapies on astrocyte function and theorize how astrocytes may be intentionally targeted for more efficacious therapeutic outcomes. Given their integral role in normal neuronal functioning, incorporating astrocytes as key criteria for AD drug development can only lead to more effective therapies for the millions of AD sufferers worldwide. LINKED ARTICLES: This article is part of a themed section on Therapeutics for Dementia and Alzheimer's Disease: New Directions for Precision Medicine. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.18/issuetoc.
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Affiliation(s)
- Jessica S Sadick
- Neuroscience Institute, NYU Langone Medical Center, New York, USA
| | - Shane A Liddelow
- Neuroscience Institute, NYU Langone Medical Center, New York, USA.,Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, USA.,Department of Pharmacology and Therapeutics, The University of Melbourne, Melbourne, Victoria, Australia
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14
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Verkhratsky A, Chvátal A. NMDA Receptors in Astrocytes. Neurochem Res 2019; 45:122-133. [DOI: 10.1007/s11064-019-02750-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 01/22/2019] [Accepted: 02/05/2019] [Indexed: 12/12/2022]
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15
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Skowrońska K, Obara-Michlewska M, Zielińska M, Albrecht J. NMDA Receptors in Astrocytes: In Search for Roles in Neurotransmission and Astrocytic Homeostasis. Int J Mol Sci 2019; 20:ijms20020309. [PMID: 30646531 PMCID: PMC6358855 DOI: 10.3390/ijms20020309] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 01/08/2019] [Accepted: 01/10/2019] [Indexed: 12/15/2022] Open
Abstract
Studies of the last two decades have demonstrated the presence in astrocytic cell membranes of N-methyl-d-aspartate (NMDA) receptors (NMDARs), albeit their apparently low abundance makes demonstration of their presence and function more difficult than of other glutamate (Glu) receptor classes residing in astrocytes. Activation of astrocytic NMDARs directly in brain slices and in acutely isolated or cultured astrocytes evokes intracellular calcium increase, by mutually unexclusive ionotropic and metabotropic mechanisms. However, other than one report on the contribution of astrocyte-located NMDARs to astrocyte-dependent modulation of presynaptic strength in the hippocampus, there is no sound evidence for the significant role of astrocytic NMDARs in astrocytic-neuronal interaction in neurotransmission, as yet. Durable exposure of astrocytic and neuronal co-cultures to NMDA has been reported to upregulate astrocytic synthesis of glutathione, and in this way to increase the antioxidative capacity of neurons. On the other hand, overexposure to NMDA decreases, by an as yet unknown mechanism, the ability of cultured astrocytes to express glutamine synthetase (GS), aquaporin-4 (AQP4), and the inward rectifying potassium channel Kir4.1, the three astroglia-specific proteins critical for homeostatic function of astrocytes. The beneficial or detrimental effects of astrocytic NMDAR stimulation revealed in the in vitro studies remain to be proven in the in vivo setting.
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Affiliation(s)
- Katarzyna Skowrońska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawińskiego Str., 02-106 Warsaw, Poland.
| | - Marta Obara-Michlewska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawińskiego Str., 02-106 Warsaw, Poland.
| | - Magdalena Zielińska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawińskiego Str., 02-106 Warsaw, Poland.
| | - Jan Albrecht
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawińskiego Str., 02-106 Warsaw, Poland.
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16
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Skowrońska K, Obara-Michlewska M, Czarnecka A, Dąbrowska K, Zielińska M, Albrecht J. Persistent Overexposure to N-Methyl-D-Aspartate (NMDA) Calcium-Dependently Downregulates Glutamine Synthetase, Aquaporin 4, and Kir4.1 Channel in Mouse Cortical Astrocytes. Neurotox Res 2018; 35:271-280. [PMID: 30220059 PMCID: PMC6313349 DOI: 10.1007/s12640-018-9958-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 08/31/2018] [Accepted: 09/07/2018] [Indexed: 11/25/2022]
Abstract
Astrocytes express N-methyl-d-aspartate (NMDA) receptor (NMDAR) but its functions in these cells are not well defined. This study shows that the sustained exposure (8–72 h) of mouse astrocytes to NMDA decreases the expression of the functional astroglia-specific proteins, glutamine synthetase (GS), and the water channel protein aquaporin-4 (AQP4) and also reduces GS activity. Similar to rat astrocytes (Obara-Michlewska et al. Neurochem Int 88:20–25, 2015), the exposure of mouse astrocytes to NMDA also decreased the expression of the inward rectifying potassium channel Kir4.1. NMDA failed to elicit the effects in those cells incubated in the absence of Ca2+ and in those in which the GluN1 subunit of the NMDAR was silenced with GluN1 siRNA. The downregulation of GS, AQP4, and Kir4.1 observed in vitro may reflect NMDAR-mediated alterations of astrocytic functions noted in central nervous system pathologies associated with increased glutamate (Glu) release and excitotoxic tissue damage.
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Affiliation(s)
- Katarzyna Skowrońska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland
| | - Marta Obara-Michlewska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland
| | - Anna Czarnecka
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland
| | - Katarzyna Dąbrowska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland
| | - Magdalena Zielińska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland
| | - Jan Albrecht
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego St. 5, 02-106, Warsaw, Poland.
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17
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Elitt MS, Shick HE, Madhavan M, Allan KC, Clayton BLL, Weng C, Miller TE, Factor DC, Barbar L, Nawash BS, Nevin ZS, Lager AM, Li Y, Jin F, Adams DJ, Tesar PJ. Chemical Screening Identifies Enhancers of Mutant Oligodendrocyte Survival and Unmasks a Distinct Pathological Phase in Pelizaeus-Merzbacher Disease. Stem Cell Reports 2018; 11:711-726. [PMID: 30146490 PMCID: PMC6135742 DOI: 10.1016/j.stemcr.2018.07.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/30/2018] [Accepted: 07/30/2018] [Indexed: 01/15/2023] Open
Abstract
Pelizaeus-Merzbacher disease (PMD) is a fatal X-linked disorder caused by loss of myelinating oligodendrocytes and consequent hypomyelination. The underlying cellular and molecular dysfunctions are not fully defined, but therapeutic enhancement of oligodendrocyte survival could restore functional myelination in patients. Here we generated pure, scalable quantities of induced pluripotent stem cell-derived oligodendrocyte progenitor cells (OPCs) from a severe mouse model of PMD, Plp1jimpy. Temporal phenotypic and transcriptomic studies defined an early pathological window characterized by endoplasmic reticulum (ER) stress and cell death as OPCs exit their progenitor state. High-throughput phenotypic screening identified a compound, Ro 25-6981, which modulates the ER stress response and rescues mutant oligodendrocyte survival in jimpy, in vitro and in vivo, and in human PMD oligocortical spheroids. Surprisingly, increasing oligodendrocyte survival did not restore subsequent myelination, revealing a second pathological phase. Collectively, our work shows that PMD oligodendrocyte loss can be rescued pharmacologically and defines a need for multifactorial intervention to restore myelination.
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Affiliation(s)
- Matthew S Elitt
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - H Elizabeth Shick
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Mayur Madhavan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Kevin C Allan
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Benjamin L L Clayton
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Chen Weng
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Tyler E Miller
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Daniel C Factor
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Lilianne Barbar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Baraa S Nawash
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Zachary S Nevin
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Angela M Lager
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Yan Li
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Fulai Jin
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Department of Population and Quantitative Health Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Department of Engineering and Computer Science, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Drew J Adams
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Paul J Tesar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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18
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Yang H, Yan H, Li X, Liu J, Cao S, Huang B, Huang D, Wu L. Inhibition of Connexin 43 and Phosphorylated NR2B in Spinal Astrocytes Attenuates Bone Cancer Pain in Mice. Front Cell Neurosci 2018; 12:129. [PMID: 29867362 PMCID: PMC5951934 DOI: 10.3389/fncel.2018.00129] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/23/2018] [Indexed: 12/14/2022] Open
Abstract
Bone cancer pain (BCP) is common in patients with advanced cancers when the tumors are metastasized to bone. The limited understanding of the complex pathogenesis of BCP leads to the poor effectiveness of clinical treatment. Previous studies have shown that astrocyte-specific connexin (Cx) 43, a forming protein of gap junction (GJ) and hemichannel, and N-methyl-D-aspartate receptors (NMDARs), especially the phosphorylated NMDAR 2B subunit (NR2B) phosphorylated NR2B (p-NR2B) subunit are involved in BCP. However, the relationship between Cx43 and p-NR2B in BCP remains unclear. In the present study, we investigated the expressions of Cx43, glial fibrillary acidic protein (GFAP, a marker of astrocytes), and p-NR2B in the spinal dorsal horn (SDH) in a mouse model of BCP established by intra-femural inoculation of Lewis lung carcinoma (LLC) cells via intrathecal (ith) injection of the GJ/hemichannel blocker carbenoxolone (CARB) and the NMDAR antagonist MK801, respectively. We found that the characters of BCP were mimicked by intra-femural inoculation of LLC cells in mice, and the expressions of Cx43, GFAP and p-NR2B in BCP mice were remarkably increased in a time-dependent manner from day 7 to day 21 after cell inoculation with a gradual aggravate in spontaneous pain and mechanical allodynia. Furthermore, Cx43 was predominantly expressed in the spinal astrocytes. Both CARB and MK801 inhibited the expressions of Cx43, GFAP and p-NR2B with attenuated pain hypersensitivity in BCP mice. In addition, Cx43 was co-localized with p-NR2B in the SDH, which further evidenced the presence of functional NR2B in the spinal astrocytes in BCP mice. Our findings demonstrate that inhibition of Cx43 and p-NR2B in spinal astrocytes could attenuate BCP in mice and Cx43 and p-NR2B in the astrocytes of the SDH may play an important role via their combination action in the development and maintenance of BCP in mice. These results may provide a potential therapeutic target in the prevention and/or treatment of BCP.
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Affiliation(s)
- Hui Yang
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, China.,Department of Physiology, School of Basic Medical Science, Central South University, Changsha, China.,Department of Pain, The Third Xiangya Hospital and Institute of Pain Medicine, Central South University, Changsha, China
| | - Hui Yan
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Xin Li
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, China.,Department of Pain, The Third Xiangya Hospital and Institute of Pain Medicine, Central South University, Changsha, China
| | - Jing Liu
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, China.,Department of Pain, The Third Xiangya Hospital and Institute of Pain Medicine, Central South University, Changsha, China
| | - Shousong Cao
- Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Baisheng Huang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Dong Huang
- Department of Pain, The Third Xiangya Hospital and Institute of Pain Medicine, Central South University, Changsha, China
| | - Lixiang Wu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha, China
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19
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Li Y, Chang L, Song Y, Gao X, Roselli F, Liu J, Zhou W, Fang Y, Ling W, Li H, Almeida OFX, Wu Y. Astrocytic GluN2A and GluN2B Oppose the Synaptotoxic Effects of Amyloid-β1-40 in Hippocampal Cells. J Alzheimers Dis 2018; 54:135-48. [PMID: 27497478 DOI: 10.3233/jad-160297] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Early-stage Alzheimer's disease (AD) is characterized by synaptic dysfunction, a phenomenon in which soluble oligomers of amyloid-beta (Aβ) and N-methyl-D-aspartate receptor (NMDAR) are implicated. Here, we demonstrated that astrocytes express NMDARs and therefore have the potential to modulate the synaptotoxic actions of Aβ. We found that specific pharmacological antagonism of two of the major NMDAR subunits, GluN2A and GluN2B, exacerbates Aβ-induced synaptotoxicity suggesting, for the first time, that astrocytic GluN2A and GluN2B mediate synaptoprotection. From the perspective of the pathogenic mechanisms of Alzheimer's disease, in which Aβ and NMDAR play significant roles, these observations are striking since neuronal GluN2A and GluN2B are well known modulators of neurodegeneration. We did initial studies to understand the basis for the differential effects of astrocytic and neuronal GluN2A and GluN2B in the promotion of synapse survival, and identified a neurotrophin produced by astrocytes, nerve growth factor β (β-NGF), as a likely mediator of the synaptoprotective effects of astrocytic GluN2A and GluN2B activation. The results presented suggest that astrocytes may be suitable druggable targets for the prevention and/or delay of the synaptic loss that occurs during early stages of AD.
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Affiliation(s)
- Yan Li
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Lirong Chang
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yizhi Song
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Xianghong Gao
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Francesco Roselli
- Departments of Neurology and Anatomy, University of Ulm School of Medicine, Germany.,Max Planck Institute of Psychiatry, Munich, Germany
| | - Jinping Liu
- School of Medicine, Tsinghua University, Beijing, China
| | - Wei Zhou
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Yuan Fang
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Wei Ling
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Hui Li
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | | | - Yan Wu
- Department of Anatomy, Ministry of Science and Technology Laboratory of Brain Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
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20
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Freire MAM, Guimaraes JS, Santos JR, Simplício H, Gomes-Leal W. Morphometric analysis of NADPH diaphorase reactive neurons in a rat model of focal excitotoxic striatal injury. Neuropathology 2016; 36:527-534. [DOI: 10.1111/neup.12311] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/23/2016] [Accepted: 04/30/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Marco Aurelio M. Freire
- Postgraduate Program in Health and Society; Faculty of Health Sciences, State University of Rio Grande do Norte (UERN); Mossoró RN Brazil
- Laboratory of Experimental Neuroprotection and Neuroregeneration; Institute of Biological Sciences, Federal University of Pará (UFPA); Belém PA Brazil
| | - Joanilson S. Guimaraes
- Laboratory of Experimental Neuroprotection and Neuroregeneration; Institute of Biological Sciences, Federal University of Pará (UFPA); Belém PA Brazil
| | - Jose Ronaldo Santos
- Laboratory of Behavioral and Evolutionary Neurobiology; Department of Biosciences, Federal University of Sergipe (UFS); Itabaiana SE Brazil
| | - Hougelle Simplício
- Postgraduate Program in Health and Society; Faculty of Health Sciences, State University of Rio Grande do Norte (UERN); Mossoró RN Brazil
- Anita Garibaldi Center for Education and Research in Health; Santos Dumont Institute (ISD); Macaíba RN Brazil
- Edmond and Lily Safra International Institute of Neuroscience; Santos Dumont Institute (ISD); Macaíba RN Brazil
| | - Walace Gomes-Leal
- Laboratory of Experimental Neuroprotection and Neuroregeneration; Institute of Biological Sciences, Federal University of Pará (UFPA); Belém PA Brazil
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21
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GE CL, WANG XM, HUANG ZG, XIA Q, WANG N, XU DJ. Tongqiao Huoxue Decoction ameliorates learning and memory defects in rats with vascular dementia by up-regulating the Ca 2+ -CaMKII-CREB pathway. Chin J Nat Med 2015; 13:823-830. [DOI: 10.1016/s1875-5364(15)30086-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Indexed: 10/22/2022]
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22
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Sühs KW, Wegner F, Skripuletz T, Trebst C, Tayeb SB, Raab P, Stangel M. Heterogeneity of clinical features and corresponding antibodies in seven patients with anti-NMDA receptor encephalitis. Exp Ther Med 2015; 10:1283-1292. [PMID: 26622479 PMCID: PMC4577954 DOI: 10.3892/etm.2015.2689] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 07/10/2015] [Indexed: 12/25/2022] Open
Abstract
Anti-N-methyl D-aspartate (NMDA) receptor encephalitis is the most common type of encephalitis in the spectrum of autoimmune encephalitis defined by antibodies targeting neuronal surface antigens. In the present study, the clinical spectrum of this disease is presented using instructive cases in correlation with the anti-NMDA receptor antibody titers in the cerebrospinal fluid (CSF) and serum. A total of 7 female patients admitted to the hospital of Hannover Medical School (Hannover, Germany) between 2008 and 2014 were diagnosed with anti-NMDA receptor encephalitis. Among these patients, 3 cases were selected to illustrate the range of similar and distinct clinical features across the spectrum of the disease and to compare anti-NMDA antibody levels throughout the disease course. All patients received immunosuppressive treatment with methylprednisolone, intravenous immunoglobulin and/or plasmapheresis, followed in the majority of patients by second-line therapy with rituximab and cyclophosphamide. The disease course correlated with NMDA receptor antibody titers, and to a greater extent with the ratio between antibody titer and protein concentration. A favorable clinical outcome with a modified Rankin Scale (mRS) score of ≤1 was achieved in 4 patients, 1 patient had an mRS score of 2 after 3 months of observation only, whereas 2 patients remained severely impaired (mRS score 4). Early and aggressive immunosuppressive treatment appears to support a good clinical outcome; however, the clinical signs and symptoms differ distinctively and treatment decisions have to be made on an individual basis.
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Affiliation(s)
- Kurt-Wolfram Sühs
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
| | - Florian Wegner
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
| | - Thomas Skripuletz
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
| | - Corinna Trebst
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
| | - Said Ben Tayeb
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
| | - Peter Raab
- Department of Neuroradiology, Hannover Medical School, Hannover D-30625, Germany
| | - Martin Stangel
- Department of Neurology, Hannover Medical School, Hannover D-30625, Germany
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23
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Dzamba D, Honsa P, Valny M, Kriska J, Valihrach L, Novosadova V, Kubista M, Anderova M. Quantitative Analysis of Glutamate Receptors in Glial Cells from the Cortex of GFAP/EGFP Mice Following Ischemic Injury: Focus on NMDA Receptors. Cell Mol Neurobiol 2015; 35:1187-202. [PMID: 25994914 DOI: 10.1007/s10571-015-0212-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 05/15/2015] [Indexed: 12/21/2022]
Abstract
Cortical glial cells contain both ionotropic and metabotropic glutamate receptors. Despite several efforts, a comprehensive analysis of the entire family of glutamate receptors and their subunits present in glial cells is still missing. Here, we provide an overall picture of the gene expression of ionotropic (AMPA, kainate, NMDA) and the main metabotropic glutamate receptors in cortical glial cells isolated from GFAP/EGFP mice before and after focal cerebral ischemia. Employing single-cell RT-qPCR, we detected the expression of genes encoding subunits of glutamate receptors in GFAP/EGFP-positive (GFAP/EGFP(+)) glial cells in the cortex of young adult mice. Most of the analyzed cells expressed mRNA for glutamate receptor subunits, the expression of which, in most cases, even increased after ischemic injury. Data analyses disclosed several classes of GFAP/EGFP(+) glial cells with respect to glutamate receptors and revealed in what manner their expression correlates with the expression of glial markers prior to and after ischemia. Furthermore, we also examined the protein expression and functional significance of NMDA receptors in glial cells. Immunohistochemical analyses of all seven NMDA receptor subunits provided direct evidence that the GluN3A subunit is present in GFAP/EGFP(+) glial cells and that its expression is increased after ischemia. In situ and in vitro Ca(2+) imaging revealed that Ca(2+) elevations evoked by the application of NMDA were diminished in GFAP/EGFP(+) glial cells following ischemia. Our results provide a comprehensive description of glutamate receptors in cortical GFAP/EGFP(+) glial cells and may serve as a basis for further research on glial cell physiology and pathophysiology.
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Affiliation(s)
- David Dzamba
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, Czech Republic.,2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Pavel Honsa
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, Czech Republic
| | - Martin Valny
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, Czech Republic
| | - Jan Kriska
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, Czech Republic.,2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Lukas Valihrach
- Laboratory of Gene Expression, Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Vendula Novosadova
- Laboratory of Gene Expression, Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Mikael Kubista
- Laboratory of Gene Expression, Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4, Czech Republic.
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24
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Montes de Oca Balderas P, Aguilera P. A Metabotropic-Like Flux-Independent NMDA Receptor Regulates Ca2+ Exit from Endoplasmic Reticulum and Mitochondrial Membrane Potential in Cultured Astrocytes. PLoS One 2015; 10:e0126314. [PMID: 25954808 PMCID: PMC4425671 DOI: 10.1371/journal.pone.0126314] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 03/31/2015] [Indexed: 01/22/2023] Open
Abstract
Astrocytes were long thought to be only structural cells in the CNS; however, their functional properties support their role in information processing and cognition. The ionotropic glutamate N-methyl D-aspartate (NMDA) receptor (NMDAR) is critical for CNS functions, but its expression and function in astrocytes is still a matter of research and debate. Here, we report immunofluorescence (IF) labeling in rat cultured cortical astrocytes (rCCA) of all NMDAR subunits, with phenotypes suggesting their intracellular transport, and their mRNA were detected by qRT-PCR. IF and Western Blot revealed GluN1 full-length synthesis, subunit critical for NMDAR assembly and transport, and its plasma membrane localization. Functionally, we found an iCa2+ rise after NMDA treatment in Fluo-4-AM labeled rCCA, an effect blocked by the NMDAR competitive inhibitors D(-)-2-amino-5-phosphonopentanoic acid (APV) and Kynurenic acid (KYNA) and dependent upon GluN1 expression as evidenced by siRNA knock down. Surprisingly, the iCa2+ rise was not blocked by MK-801, an NMDAR channel blocker, or by extracellular Ca2+ depletion, indicating flux-independent NMDAR function. In contrast, the IP3 receptor (IP3R) inhibitor XestosponginC did block this response, whereas a Ryanodine Receptor inhibitor did so only partially. Furthermore, tyrosine kinase inhibition with genistein enhanced the NMDA elicited iCa2+ rise to levels comparable to those reached by the gliotransmitter ATP, but with different population dynamics. Finally, NMDA depleted the rCCA mitochondrial membrane potential (mΔψ) measured with JC-1. Our results demonstrate that rCCA express NMDAR subunits which assemble into functional receptors that mediate a metabotropic-like, non-canonical, flux-independent iCa2+ increase.
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Affiliation(s)
- Pavel Montes de Oca Balderas
- Unidad de Neurobiología Dinámica, Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía, México City, México
- * E-mail:
| | - Penélope Aguilera
- Laboratorio de Patología Vascular Cerebral, Instituto Nacional de Neurología y Neurocirugía, México City, México
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25
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Ju WK, Kim KY, Noh YH, Hoshijima M, Lukas TJ, Ellisman MH, Weinreb RN, Perkins GA. Increased mitochondrial fission and volume density by blocking glutamate excitotoxicity protect glaucomatous optic nerve head astrocytes. Glia 2015; 63:736-53. [PMID: 25557093 PMCID: PMC4373968 DOI: 10.1002/glia.22781] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 12/03/2014] [Indexed: 12/31/2022]
Abstract
Abnormal structure and function of astrocytes have been observed within the lamina cribrosa region of the optic nerve head (ONH) in glaucomatous neurodegeneration. Glutamate excitotoxicity-mediated mitochondrial alteration has been implicated in experimental glaucoma. However, the relationships among glutamate excitotoxicity, mitochondrial alteration and ONH astrocytes in the pathogenesis of glaucoma remain unknown. We found that functional N-methyl-d-aspartate (NMDA) receptors (NRs) are present in human ONH astrocytes and that glaucomatous human ONH astrocytes have increased expression levels of NRs and the glutamate aspartate transporter. Glaucomatous human ONH astrocytes exhibit mitochondrial fission that is linked to increased expression of dynamin-related protein 1 and its phosphorylation at Serine 616. In BAC ALDH1L1 eGFP or Thy1-CFP transgenic mice, NMDA treatment induced axon loss as well as hypertrophic morphology and mitochondrial fission in astrocytes of the glial lamina. In human ONH astrocytes, NMDA treatment in vitro triggered mitochondrial fission by decreasing mitochondrial length and number, thereby reducing mitochondrial volume density. However, blocking excitotoxicity by memantine (MEM) prevented these alterations by increasing mitochondrial length, number and volume density. In glaucomatous DBA/2J (D2) mice, blocking excitotoxicity by MEM inhibited the morphological alteration as well as increased mitochondrial number and volume density in astrocytes of the glial lamina. However, blocking excitotoxicity decreased autophagosome/autolysosome volume density in both astrocytes and axons in the glial lamina of glaucomatous D2 mice. These findings provide evidence that blocking excitotoxicity prevents ONH astrocyte dysfunction in glaucomatous neurodegeneration by increasing mitochondrial fission, increasing mitochondrial volume density and length, and decreasing autophagosome/autolysosome formation. GLIA 2015;63:736-753.
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Affiliation(s)
- Won-Kyu Ju
- Department of Ophthalmology, Laboratory for Optic Nerve Biology, Hamilton Glaucoma Center, University of California San DiegoLa Jolla, California
| | - Keun-Young Kim
- Center for Research on Biological Systems, National Center for Microscopy and Imaging Research and Department of Neuroscience, University of California San DiegoLa Jolla, California
| | - You Hyun Noh
- Department of Ophthalmology, Laboratory for Optic Nerve Biology, Hamilton Glaucoma Center, University of California San DiegoLa Jolla, California
| | - Masahiko Hoshijima
- Center for Research on Biological Systems, National Center for Microscopy and Imaging Research and Department of Neuroscience, University of California San DiegoLa Jolla, California
- Department of Medicine, University of California San DiegoLa Jolla, California
| | - Thomas J Lukas
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern UniversityChicago, Illinois
| | - Mark H Ellisman
- Center for Research on Biological Systems, National Center for Microscopy and Imaging Research and Department of Neuroscience, University of California San DiegoLa Jolla, California
| | - Robert N Weinreb
- Department of Ophthalmology, Laboratory for Optic Nerve Biology, Hamilton Glaucoma Center, University of California San DiegoLa Jolla, California
| | - Guy A Perkins
- Center for Research on Biological Systems, National Center for Microscopy and Imaging Research and Department of Neuroscience, University of California San DiegoLa Jolla, California
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26
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NMDA receptor antagonists ketamine and Ro25-6981 inhibit evoked release of glutamate in vivo in the subiculum. Transl Psychiatry 2014; 4:e395. [PMID: 24893066 PMCID: PMC4080320 DOI: 10.1038/tp.2014.39] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 04/22/2014] [Indexed: 01/20/2023] Open
Abstract
Preclinical and clinical data have identified ketamine, a non-selective NMDAR (N-methyl-D-aspartate receptor) antagonist, as a promising medication for patients who do not respond to treatment with monoamine-based antidepressants. Moreover, unlike the current monoamine-based antidepressants, ketamine has a long-lasting effect already after a single dose. The mechanisms of ketamine action remain to be fully understood. Using a recently developed microelectrode array (MEA), which allows sub-second measurements of fluctuating glutamate concentrations, we studied here the effects of in vivo local application of the ketamine and of the N2B subunit-specific antagonist Ro25-6981 upon evoked glutamate release. Both ligands inhibit glutamate release in subregions of the hippocampus and prefrontal cortex. Likewise, acute systemic ketamine treatment, at an antidepressant dose, caused a reduction in evoked glutamate release in the subiculum. We suggest that the effects of ketamine and Ro25-6981 in the subiculum could involve blockade of presynaptic NMDA receptors containing N2B subunits.
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27
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Smith KL, John CS, Sypek EI, Ongür D, Cohen BM, Barry SM, Bechtholt AJ. Exploring the role of central astrocytic glutamate uptake in ethanol reward in mice. Alcohol Clin Exp Res 2014; 38:1307-14. [PMID: 24655029 DOI: 10.1111/acer.12361] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 12/18/2013] [Indexed: 01/16/2023]
Abstract
BACKGROUND Alcoholism is associated with specific brain abnormalities revealed through postmortem studies, including a reduction in glial cell number and dysregulated glutamatergic neurotransmission. Whether these abnormalities contribute to the etiology of alcoholism, are consequences of alcohol use, or both is still unknown. METHODS We investigated the role of astrocytic glutamate uptake in ethanol (EtOH) binge drinking in mice, using the "drinking in the dark" (DID) paradigm by blocking the astrocytic glutamate transporter (GLT-1) with intracerebroventricular (ICV) administration of dihydrokainic acid (DHK). To determine whether astrocytic glutamate uptake regulates the conditioned rewarding effects of EtOH, we examined the effects of ICV DHK on the acquisition and expression of EtOH-induced conditioned place preference. RESULTS Blocking central astrocytic glutamate uptake selectively attenuated EtOH binge drinking behavior in mice. DHK did not alter the acquisition or expression of preference for EtOH-associated cues, indicating that reduced astrocytic glutamate trafficking may decrease binge-like drinking without altering the conditioned rewarding effects of EtOH. CONCLUSIONS Several alternative conclusions are plausible, however, interpreting these data in the context of the human literature, these findings suggest that the reduction of glia in the alcoholic brain may not be a predisposing factor to developing alcoholism and could be a consequence of EtOH toxicity that decreases excessive EtOH intake.
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Affiliation(s)
- Karen L Smith
- Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, Massachusetts; Laboratory of Addictive Disorders, Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts
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28
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Activation of NMDA receptor of glutamate influences MMP-2 activity and proliferation of glioma cells. Neurol Sci 2013; 35:823-9. [DOI: 10.1007/s10072-013-1604-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 12/10/2013] [Indexed: 02/07/2023]
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29
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Gibbons M, Smeal R, Takahashi D, Vargas J, Wilcox K. Contributions of astrocytes to epileptogenesis following status epilepticus: opportunities for preventive therapy? Neurochem Int 2013; 63:660-9. [PMID: 23266599 PMCID: PMC4353644 DOI: 10.1016/j.neuint.2012.12.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 12/09/2012] [Accepted: 12/13/2012] [Indexed: 12/22/2022]
Abstract
Status epilepticus (SE) is a life threatening condition that often precedes the development of epilepsy. Traditional treatments for epilepsy have been focused on targeting neuronal mechanisms contributing to hyperexcitability, however, approximately 30% of patients with epilepsy do not respond to existing neurocentric pharmacotherapies. A growing body of evidence has demonstrated that profound changes in the morphology and function of astrocytes accompany SE and persist in epilepsy. Astrocytes are increasingly recognized for their diverse roles in modulating neuronal activity, and understanding the changes in astrocytes following SE could provide important clues about the mechanisms underlying seizure generation and termination. By understanding the contributions of astrocytes to the network changes underlying epileptogenesis and the development of epilepsy, we will gain a greater appreciation of the contributions of astrocytes to dynamic circuit changes, which will enable us to develop more successful therapies to prevent and treat epilepsy. This review summarizes changes in astrocytes following SE in animal models and human temporal lobe epilepsy and addresses the functional consequences of those changes that may provide clues to the process of epileptogenesis.
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Affiliation(s)
- M.B. Gibbons
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT
| | - R.M. Smeal
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT
| | - D.K. Takahashi
- Department of Neurology, Stanford University, Palo Alto, CA
| | - J.R. Vargas
- Department of Neurology, University of Utah, Salt Lake City, UT
| | - K.S. Wilcox
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT
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30
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Retrograde Synaptic Signaling Mediated by K+ Efflux through Postsynaptic NMDA Receptors. Cell Rep 2013; 5:941-51. [DOI: 10.1016/j.celrep.2013.10.026] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 09/03/2013] [Accepted: 10/16/2013] [Indexed: 11/18/2022] Open
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31
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Block L, Björklund U, Westerlund A, Jörneberg P, Biber B, Hansson E. A new concept affecting restoration of inflammation-reactive astrocytes. Neuroscience 2013; 250:536-45. [DOI: 10.1016/j.neuroscience.2013.07.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/15/2013] [Accepted: 07/15/2013] [Indexed: 01/30/2023]
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32
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Vargas JR, Takahashi DK, Thomson KE, Wilcox KS. The expression of kainate receptor subunits in hippocampal astrocytes after experimentally induced status epilepticus. J Neuropathol Exp Neurol 2013; 72:919-32. [PMID: 24042195 PMCID: PMC3880830 DOI: 10.1097/nen.0b013e3182a4b266] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Astrocytes have emerged as active participants of synaptic transmission and are increasingly implicated in neurologic disorders including epilepsy. Adult glial fibrillary acidic protein (GFAP)-positive hippocampal astrocytes are not known for ionotropic glutamate receptor expression under basal conditions. Using a chemoconvulsive status epilepticus (SE) model of temporal lobe epilepsy, we show by immunohistochemistry and colocalization analysis that reactive hippocampal astrocytes express kainate receptor (KAR) subunits after SE. In the CA1 region, GluK1, GluK2/3, GluK4, and GluK5 subunit expression was observed in GFAP-positive astrocytes during the seizure-free or "latent" period 1 week after SE. At 8 weeks after SE, a time after SE when spontaneous behavioral seizures occur, the GluK1 and GluK5 subunits remained expressed at significant levels. Kainate receptor subunit expression was found in astrocytes in the hippocampus and surrounding cortex but not in GFAP-positive astrocytes of striatum, olfactory bulb, or brainstem. To examine hippocampal KAR expression more broadly, astroglial-enriched tissue fractions were prepared from dissected hippocampi and were found to have greater GluK4 expression after SE than controls. These results demonstrate that astrocytes begin to express KARs after seizure activity and suggest that their expression may contribute to the pathophysiology of epilepsy.
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Affiliation(s)
- Jay R. Vargas
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, Utah
| | - Daniel K. Takahashi
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, Utah
| | - Kyle E. Thomson
- Department of Bioengineering, University of Utah, Salt Lake City, Utah
| | - Karen S. Wilcox
- Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, Utah
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, Utah
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33
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Murugan M, Ling EA, Kaur C. Dysregulated glutamate uptake by astrocytes causes oligodendroglia death in hypoxic perventricular white matter damage. Mol Cell Neurosci 2013; 56:342-54. [PMID: 23859823 DOI: 10.1016/j.mcn.2013.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 01/31/2023] Open
Abstract
Excess glutamate mediates damage to oligodendroglia, resulting in myelination disturbances characteristic of hypoxic periventricular white matter (PWM) damage. We sought to examine if hypoxia altered the expression of astroglial excitatory amino acid transporters (EAAT1, EAAT2 and EAAT3) in the PWM, and, if so, whether it activated astroglial N-methyl D-aspartate receptors (NMDAR) which might lead to apoptosis of oligodendroglia. EAAT expression in the PWM of neonatal rats was measured at different time points after hypoxic exposure; it was attenuated at 7 and 14 d following hypoxia. Hypoxia prevented the uptake of glutamate by astroglial EAATs causing increased levels of extracellular glutamate. Excess glutamate augmented the expression of functional astroglial NMDAR. Following hypoxia, an increase in gap junction proteins between astroglia and oligodendroglia aided in the spreading of NMDAR-mediated excitotoxic calcium signals into the latter cell type triggering its apoptosis. Hence, dysregulated glutamate homeostasis is believed to contribute to hypoxia-induced death of oligodendroglia leading to neonatal PWM damage.
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Affiliation(s)
- Madhuvika Murugan
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
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Castillo C, Norcini M, Martin Hernandez L, Correa G, Blanck T, Recio-Pinto E. Satellite glia cells in dorsal root ganglia express functional NMDA receptors. Neuroscience 2013; 240:135-46. [DOI: 10.1016/j.neuroscience.2013.02.031] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 01/29/2013] [Accepted: 02/13/2013] [Indexed: 01/06/2023]
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He S, Shao LR, Wang Y, Bausch SB. Synaptic and extrasynaptic plasticity in glutamatergic circuits involving dentate granule cells following chronic N-methyl-D-aspartate receptor inhibition. J Neurophysiol 2013; 109:1535-47. [PMID: 23255721 PMCID: PMC3602941 DOI: 10.1152/jn.00667.2012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 12/12/2012] [Indexed: 01/25/2023] Open
Abstract
Chronic global N-methyl-d-aspartate receptor (NMDAR) blockade leads to changes in glutamatergic transmission. The impact of more subunit-selective NMDAR inhibition on glutamatergic circuits remains incomplete. To this end, organotypic hippocampal slice cultures were treated for 17-21 days with the high-affinity competitive antagonist d-aminophosphonovaleric acid (d-APV), the allosteric GluN2B-selective antagonist Ro25-6981, or the newer competitive GluN2A-preferring antagonist NVP-AAM077. Electrophysiological recordings from dentate granule cells revealed that chronic d-APV treatment increased, whereas chronic Ro25-6981 reduced, epileptiform event-associated large-amplitude spontaneous excitatory postsynaptic currents (sEPSC) compared with all other treatment groups, consistent with opposite effects on glutamatergic networks. Presynaptically, chronic d-APV or Ro25-6981 increased small-amplitude sEPSCs and AMPA/kainate receptor-mediated miniature EPSCs (mEPSCAMPAR) frequency. Chronic d-APV or NVP-AAM077, but not Ro25-6981, increased putative vGlut1-positive glutamatergic synapses. Postsynaptically, chronic d-APV dramatically increased mEPSCAMPAR and profoundly decreased NMDAR-mediated mEPSC (mEPSCNMDAR) measures, suggesting increased AMPAR/NMDAR ratio. Ro25-6981 decreased mEPSCAMPAR charge transfer and modestly decreased mEPSCNMDAR frequency and decay, suggesting downward scaling of AMPAR and NMDAR function without dramatically altering AMPAR/NMDAR ratio. Extrasynaptically, threo-β-benzyloxyaspartate-enhanced "tonic" NMDAR current amplitude and activated channel number estimates were significantly increased only by chronic Ro25-6981. For intrinsic excitability, action potential threshold was slightly more negative following chronic d-APV or NVP-AAM077. The predominant pro-excitatory effects of chronic d-APV are consistent with increased glutamatergic transmission and network excitability. The minor effects of chronic NVP-AAM077 on action potential threshold and synapse number are consistent with minimal effects on circuit function. The chronic Ro25-6981-induced downward scaling of synaptic AMPAR and NMDAR function is consistent with decreased postsynaptic glutamate receptors and reduced network excitability.
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Affiliation(s)
- Shuijin He
- Graduate Program in Neuroscience, Uniformed Services University School of Medicine, Bethesda, Maryland 20814-4799, USA
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Seo JY, Yan BC, Park JH, Ahn JH, Kim IH, Lee JC, Kwon YG, Kim YM, Cho JH, Won MH. Comparison of the immunoreactivities of NMDA receptors between the young and adult hippocampal CA1 region induced by experimentally transient cerebral ischemia. J Neurol Sci 2012; 325:108-14. [PMID: 23287813 DOI: 10.1016/j.jns.2012.12.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/07/2012] [Accepted: 12/11/2012] [Indexed: 12/01/2022]
Abstract
Young gerbils are much more resistant to transient cerebral ischemia than the adult. In the present study, we observed that about 90% of CA1 pyramidal cells in the adult hippocampus died 4days post-ischemia; however, about 56% of them in the young hippocampus died at 7days post-ischemia. To compare excitotoxicity between them, we carried out immunoreactivities of NMDA receptor 1 (NMDAR1) and NMDAR2A/B in the hippocampal CA1 region (CA1) induced by 5min of transient cerebral ischemia in the young and adult gerbils. Their immunoreactivities and protein levels in the young sham-group were much lower than those in the adult sham-group. Four days after ischemia-reperfusion, they were significantly decreased in the adult ischemia-group; however, in the young ischemia-group, they were much higher than those in the adult. Seven days after ischemia-reperfusion, NMDAR1 immunoreactivity and its level in the young were much higher than those in the adult; NMDAR2A/B immunoreactivity and its level in the young were lower than in the adult. In brief, the immunoreactivities of NMDARs were not decreased in the ischemic CA1 region of the young 4days after transient cerebral ischemia. This finding indicates that longer maintenance of NMDARs may contribute to less and more delayed neuronal death/damage in the young CA1.
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Affiliation(s)
- Jeong Yeol Seo
- Department of Emergency Medicine, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, 200-702 South Korea
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Kaalund SS, Riise J, Broberg BV, Fabricius K, Karlsen AS, Secher T, Plath N, Pakkenberg B. Differential expression of parvalbumin in neonatal phencyclidine-treated rats and socially isolated rats. J Neurochem 2012; 124:548-57. [PMID: 23083323 DOI: 10.1111/jnc.12061] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 10/02/2012] [Accepted: 10/02/2012] [Indexed: 12/11/2022]
Abstract
Decreased parvalbumin expression is a hallmark of the pathophysiology of schizophrenia and has been associated with abnormal cognitive processing and decreased network specificity. It is not known whether this decrease is due to reduced expression of the parvalbumin protein or degeneration of parvalbumin-positive interneurons (PV(+) interneurons). In this study, we examined PV(+) expression in two rat models of cognitive dysfunction in schizophrenia: the environmental social isolation (SI) and pharmacological neonatal phencyclidine (neoPCP) models. Using a stereological method, the optical fractionator, we counted neurons, PV(+) interneurons, and glial cells in the medial prefrontal cortex (mPFC) and hippocampus (HPC). In addition, we quantified the mRNA level of parvalbumin in the mPFC. There was a statistically significant reduction in the number of PV(+) interneurons (p = 0.021) and glial cells (p = 0.024) in the mPFC of neonatal phencyclidine rats, but not in SI rats. We observed no alterations in the total number of neurons, hippocampal PV(+) interneurons, parvalbumin mRNA expression or volume of the mPFC or HPC in the two models. Thus, as the total number of neurons remains unchanged following phencyclidine (PCP) treatment, we suggest that the decreased number of counted PV(+) interneurons represents a reduced parvalbumin protein expression below immunohistochemical detection limit rather than a true cell loss. Furthermore, these results indicate that the effect of neonatal PCP treatment is not limited to neuronal populations.
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Affiliation(s)
- Sanne S Kaalund
- Research Laboratory for Stereology and Neuroscience, Bispebjerg University Hospital, Copenhagen, Denmark
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Seo M, Kim JH, Cho YE, Baek MC, Suk K. Hypothermic regulation of astrocyte proteome profile in experimental stroke. Electrophoresis 2012; 33:3835-48. [DOI: 10.1002/elps.201200331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/24/2012] [Accepted: 09/16/2012] [Indexed: 01/08/2023]
Affiliation(s)
- Minchul Seo
- Department of Pharmacology; Brain Science & Engineering Institute; Kyungpook National University School of Medicine; Daegu; Korea
| | - Jong-Heon Kim
- Department of Pharmacology; Brain Science & Engineering Institute; Kyungpook National University School of Medicine; Daegu; Korea
| | - Young-Eun Cho
- Department of Molecular Medicine; Cell & Matrix Biology Research Institute; Kyungpook National University School of Medicine; Daegu; Korea
| | - Moon-Chang Baek
- Department of Molecular Medicine; Cell & Matrix Biology Research Institute; Kyungpook National University School of Medicine; Daegu; Korea
| | - Kyoungho Suk
- Department of Pharmacology; Brain Science & Engineering Institute; Kyungpook National University School of Medicine; Daegu; Korea
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Huang C, Wu J, Liao R, Zhang W. SKF83959, an agonist of phosphatidylinositol-linked D(1)-like receptors, promotes ERK1/2 activation and cell migration in cultured rat astrocytes. PLoS One 2012. [PMID: 23185493 PMCID: PMC3501487 DOI: 10.1371/journal.pone.0049954] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Extracellular signal-regulated kinase 1/2 (ERK1/2) is a member of the mitogen-activated protein kinase family. It can mediate cell migration. Classical dopamine receptor-mediated ERK1/2 phosphorylation is widely studied in neurons. Here, we report that ERK1/2 phosphorylation is also modulated by putative phosphatidylinositol-linked D1-like receptors in cultured rat astrocytes. 6-chloro-7,8-dihydroxy-3-methyl-1-(3-methylphenyl)-2,3,4,5-tetrahydro-1H-3-benzazepine (SKF83959), an agonist of the putative phosphatidylinositol-linked D1-like receptors, was found to enhance ERK1/2 phosphorylation, which then promoted the migration of cultured astrocytes. The SKF83959-induced ERK1/2 phosphorylation was found to be Ca2+-independent based on the following observations: i. chelating intracellular Ca2+ did not inhibit ERK1/2 phosphorylation and astrocyte migration; ii. blockage of the release of intracellular Ca2+ from the endoplasmic reticulum by an inhibitor of inositol 1,4,5-trisphosphate (IP3) receptor did not attenuate ERK1/2 phosphorylation. However, inhibition of phospholipase C (PLC), the upstream molecule of internal Ca2+ release, disabled SKF83959’s ability to elevate the level of ERK1/2 phosphorylation. Both non-selective protein kinase C (PKC) inhibitor and PKCδ selective inhibitor prevented ERK1/2 phosphorylation increase and astrocyte migration, but PKCα inhibitor did not. This suggests that Ca2+-independent and diacylglycerol-dependent PKCδ acts downstream of putative phosphatidylinositol-linked D1-like receptor activation and mediates SKF83959-induced elevation of ERK1/2 phosphorylation in order to modulate astrocyte migration. In conclusion, our results demonstrate that SKF83959-induced increases in ERK1/2 phosphorylation and astrocyte migration are dependent on PLC-PKCδ signals. This might help us to further understand the functions of the putative phosphatidylinositol-linked D1-like receptors in the nervous system.
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Affiliation(s)
- Chao Huang
- Department of Pharmacology, School of Medicine, Nantong University, Nantong, Jiangsu, People's Republic of China
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40
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Anoxic depolarization of hippocampal astrocytes: possible modulation by P2X7 receptors. Neurochem Int 2012; 62:15-22. [PMID: 23147683 DOI: 10.1016/j.neuint.2012.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/31/2012] [Accepted: 11/01/2012] [Indexed: 12/30/2022]
Abstract
Current responses from CA1 neurons and stratum oriens astrocytes were recorded from hippocampal brain slices by means of the whole-cell patch-clamp technique. Anoxic depolarization (AD) was induced by an oxygen/glucose-deprived (OGD) medium also containing sodium iodoacetate and antimycin, in order to block glycolysis and oxidative phosphorylation, respectively. Anoxic depolarization has been reported to be due to the sudden increase of the extracellular K(+) concentration and the accompanying explosive rise in glutamate concentration. We asked ourselves whether the release of ATP activating P2X7 receptors is also involved in the AD. Although, the AD was evoked in absolute synchrony in neurons and astrocytes, and the NMDA receptor antagonistic AP-5 depressed these responses, neither the non-selective P2 receptor antagonist PPADS, nor the highly selective P2X7 receptor antagonist A438079 interfered with the AD or its delay time in neurons/astrocytes after inducing chemical hypoxia. However, A438079, but not PPADS increased in astrocytes the slow inward current observed in a hypoxic medium. It is concluded that ATP co-released with glutamate by hypoxic stimulation has only a minor function in the present brain slice system.
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Gérard F, Hansson E. Inflammatory activation enhances NMDA-triggered Ca2+ signalling and IL-1β secretion in primary cultures of rat astrocytes. Brain Res 2012; 1473:1-8. [PMID: 22836011 DOI: 10.1016/j.brainres.2012.07.032] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 03/13/2012] [Accepted: 07/17/2012] [Indexed: 10/28/2022]
Abstract
The aim of the present study was to measure the effects of NMDA receptor antagonists on rat astroglial-enriched primary cultures after incubation with lipopolysaccharide (LPS), with a view to explaining the role of NMDA receptors in the inflammatory activation of astrocytes. First, the presence of NMDA receptor subunits was confirmed at the protein level by immunocytochemical methods. The presence of functional NMDA receptors containing GluN2B subunits was then established by ratiometric fluorescent Ca(2+) imaging which revealed transient NMDA-triggered Ca(2+) responses. These responses could be blocked by the competitive antagonist 2-amino-5-phosphonopentoate (APV) and the non-competitive GluN2B subunit-selective antagonist ifenprodil. The NMDA-evoked Ca(2+) transients were dependent on Ca(2+) release from intracellular stores via interaction with InsP3-sensitive receptors as they were blocked by thapsigargin or xestospongin C. Following 24h incubation with LPS, astroglial inflammatory activation increased IL-1β secretion and NMDA-triggered Ca(2+) transients. The addition of APV or ifenprodil inhibited these enhanced responses, suggesting that LPS exposure stimulates IL-1β release from astrocytes through a mechanism that requires NMDA receptor stimulation.
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Affiliation(s)
- Franck Gérard
- Department of Clinical Neuroscience and Rehabilitation, Institute of Neuroscience and Physiology, University of Gothenburg, Per Dubbsgatan 14, 1tr, Sahlgrenska Academy University, SE 413 45 Gothenburg, Sweden.
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Butenko O, Dzamba D, Benesova J, Honsa P, Benfenati V, Rusnakova V, Ferroni S, Anderova M. The increased activity of TRPV4 channel in the astrocytes of the adult rat hippocampus after cerebral hypoxia/ischemia. PLoS One 2012; 7:e39959. [PMID: 22761937 PMCID: PMC3384594 DOI: 10.1371/journal.pone.0039959] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 05/30/2012] [Indexed: 02/03/2023] Open
Abstract
The polymodal transient receptor potential vanilloid 4 (TRPV4) channel, a member of the TRP channel family, is a calcium-permeable cationic channel that is gated by various stimuli such as cell swelling, low pH and high temperature. Therefore, TRPV4-mediated calcium entry may be involved in neuronal and glia pathophysiology associated with various disorders of the central nervous system, such as ischemia. The TRPV4 channel has been recently found in adult rat cortical and hippocampal astrocytes; however, its role in astrocyte pathophysiology is still not defined. In the present study, we examined the impact of cerebral hypoxia/ischemia (H/I) on the functional expression of astrocytic TRPV4 channels in the adult rat hippocampal CA1 region employing immunohistochemical analyses, the patch-clamp technique and microfluorimetric intracellular calcium imaging on astrocytes in slices as well as on those isolated from sham-operated or ischemic hippocampi. Hypoxia/ischemia was induced by a bilateral 15-minute occlusion of the common carotids combined with hypoxic conditions. Our immunohistochemical analyses revealed that 7 days after H/I, the expression of TRPV4 is markedly enhanced in hippocampal astrocytes of the CA1 region and that the increasing TRPV4 expression coincides with the development of astrogliosis. Additionally, adult hippocampal astrocytes in slices or cultured hippocampal astrocytes respond to the TRPV4 activator 4-alpha-phorbol-12,-13-didecanoate (4αPDD) by an increase in intracellular calcium and the activation of a cationic current, both of which are abolished by the removal of extracellular calcium or exposure to TRP antagonists, such as Ruthenium Red or RN1734. Following hypoxic/ischemic injury, the responses of astrocytes to 4αPDD are significantly augmented. Collectively, we show that TRPV4 channels are involved in ischemia-induced calcium entry in reactive astrocytes and thus, might participate in the pathogenic mechanisms of astroglial reactivity following ischemic insult.
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Affiliation(s)
- Olena Butenko
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Second Medical Faculty, Charles University, Prague, Czech Republic
| | - David Dzamba
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Second Medical Faculty, Charles University, Prague, Czech Republic
| | - Jana Benesova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Second Medical Faculty, Charles University, Prague, Czech Republic
| | - Pavel Honsa
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- Second Medical Faculty, Charles University, Prague, Czech Republic
| | - Valentina Benfenati
- Institute for the Study of Nanostructured Material, National Research Council, Bologna, Italy
| | - Vendula Rusnakova
- Laboratory of Gene Expression, Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Stefano Ferroni
- Department of Human and General Physiology, University of Bologna, Bologna, Italy
| | - Miroslava Anderova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- * E-mail:
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Wohl SG, Schmeer CW, Isenmann S. Neurogenic potential of stem/progenitor-like cells in the adult mammalian eye. Prog Retin Eye Res 2012; 31:213-42. [DOI: 10.1016/j.preteyeres.2012.02.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 02/04/2012] [Accepted: 02/06/2012] [Indexed: 11/26/2022]
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Genomic analysis of [d-Ala2, d-Leu5] enkephalin preconditioning in cortical neuron and glial cell injury after oxygen deprivation. Brain Res 2012; 1447:91-105. [DOI: 10.1016/j.brainres.2012.01.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 01/03/2012] [Accepted: 01/20/2012] [Indexed: 01/01/2023]
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45
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Decrease of synaptic plasticity associated with alteration of information flow in a rat model of vascular dementia. Neuroscience 2012; 206:136-43. [DOI: 10.1016/j.neuroscience.2011.12.050] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 12/27/2011] [Accepted: 12/28/2011] [Indexed: 11/23/2022]
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46
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Palygin O, Lalo U, Pankratov Y. Distinct pharmacological and functional properties of NMDA receptors in mouse cortical astrocytes. Br J Pharmacol 2012; 163:1755-66. [PMID: 21449975 DOI: 10.1111/j.1476-5381.2011.01374.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Astrocytes of the mouse neocortex express functional NMDA receptors, which are not blocked by Mg(2+) ions. However, the pharmacological profile of glial NMDA receptors and their subunit composition is far from complete. EXPERIMENTAL APPROACH We tested the sensitivity of NMDA receptor-mediated currents to the novel GluN2C/D subunit-selective antagonist UBP141 in mouse cortical astrocytes and neurons. We also examined the effect of memantine, an antagonist that has substantially different affinities for GluN2A/B and GluN2C/d-containing receptors in physiological concentrations of extracellular Mg(2+). KEY RESULTS UBP141 had a strong inhibitory action on NMDA receptor-mediated transmembrane currents in the cortical layer II/III astrocytes with an IC(50) of 2.29 µM and a modest inhibitory action on NMDA-responses in the pyramidal neurons with IC(50) of 19.8 µM. Astroglial and neuronal NMDA receptors exhibited different sensitivities to memantine with IC(50) values of 2.19 and 10.8 µM, respectively. Consistent with pharmacological differences between astroglial and neuronal NMDA receptors, NMDA receptors in astrocytes showed lower Ca(2+) permeability than neuronal receptors with P(Ca) /P(Na) ratio of 3.4. CONCLUSIONS AND IMPLICATIONS The biophysical and pharmacological properties of the astrocytic NMDA receptors strongly suggest that they have a tri-heteromeric structure composed of GluN1, GluN2C/D and GluN3 subunits. The substantial difference between astroglial and neuronal NMDA receptors in their sensitivity to UBP141 and memantine may enable selective modulation of astrocytic signalling that could be very helpful for elucidating the mechanisms of neuron-glia communications. Our results may also provide the basis for the development of novel therapeutic agents specifically targeting glial signalling.
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Affiliation(s)
- Oleg Palygin
- Department of Biological Sciences, University of Warwick, Coventry, UK
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47
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N-Methyl-d-aspartate receptor antagonist MK-801 suppresses glial pro-inflammatory cytokine expression in morphine-tolerant rats. Pharmacol Biochem Behav 2011; 99:371-80. [DOI: 10.1016/j.pbb.2011.05.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 04/22/2011] [Accepted: 05/15/2011] [Indexed: 11/18/2022]
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48
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Frasca A, Aalbers M, Frigerio F, Fiordaliso F, Salio M, Gobbi M, Cagnotto A, Gardoni F, Battaglia GS, Hoogland G, Di Luca M, Vezzani A. Misplaced NMDA receptors in epileptogenesis contribute to excitotoxicity. Neurobiol Dis 2011; 43:507-15. [DOI: 10.1016/j.nbd.2011.04.024] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/15/2011] [Accepted: 04/28/2011] [Indexed: 02/07/2023] Open
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Lavenex P, Sugden SG, Davis RR, Gregg JP, Lavenex PB. Developmental regulation of gene expression and astrocytic processes may explain selective hippocampal vulnerability. Hippocampus 2011; 21:142-9. [PMID: 20014383 DOI: 10.1002/hipo.20730] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The hippocampus plays a central role in the brain network that is essential for memory function. Paradoxically, the hippocampus is also the brain structure that is most sensitive to hypoxic-ischemic episodes. Here, we show that the expression of genes associated with glycolysis and glutamate metabolism in astrocytes and the coverage of excitatory synapses by astrocytic processes undergo significant decreases in the CA1 field of the monkey hippocampus during postnatal development. Given the established role of astrocytes in the regulation of glutamate concentration in the synaptic cleft, our findings suggest that a developmental decrease in astrocytic processes could underlie the selective vulnerability of CA1 during hypoxic-ischemic episodes in adulthood, its decreased susceptibility to febrile seizures with age, as well as contribute to the emergence of selective, adultlike memory function.
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Affiliation(s)
- Pierre Lavenex
- Department of Psychiatry and Behavioral Sciences, UC Davis, Sacramento, California 95817, USA.
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50
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Long-term consequences of a prolonged febrile seizure in a dual pathology model. Neurobiol Dis 2011; 43:312-21. [PMID: 21406232 DOI: 10.1016/j.nbd.2011.02.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 01/26/2011] [Accepted: 02/27/2011] [Indexed: 12/14/2022] Open
Abstract
Clinical evidence suggests that febrile status epilepticus (SE) in children can lead to acute hippocampal injury and subsequent temporal lobe epilepsy. The contribution of febrile SE to the mechanisms underlying temporal lobe epilepsy are however poorly understood. A rat model of temporal lobe epilepsy following hyperthermic SE was previously established in our laboratory, wherein a focal cortical lesion induced at postnatal day 1 (P1), followed by a hyperthermic SE (more than 30 min) at P10, leads to hippocampal atrophy at P22 (dual pathology model) and spontaneous recurrent seizures (SRS) with mild visuospatial memory deficits in adult rats. The goal of this study was to identify the long term electrophysiological, anatomical and molecular changes in this model. Following hyperthermic SE, all cortically lesioned pups developed progressive SRS as adults, characterized by the onset of highly rhythmic activity in the hippocampus. A reduction of hippocampal volume on the side of the lesion preceded the SRS and was associated with a loss of hippocampal neurons, a marked decrease in pyramidal cell spine density, an increase in the hippocampal levels of NMDA receptor NR2A subunit, but no significant change in GABA receptors. These findings suggest that febrile SE in the abnormal brain leads to hippocampal injury that is followed by progressive network reorganization and molecular changes that contribute to the epileptogenesis as well as the observed memory deficits.
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