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Yang Y, Liu T, Li J, Yan D, Hu Y, Wu P, Fang F, McQuillan PM, Hang W, Leng J, Hu Z. General anesthetic agents induce neurotoxicity through astrocytes. Neural Regen Res 2024; 19:1299-1307. [PMID: 37905879 PMCID: PMC11467951 DOI: 10.4103/1673-5374.385857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 08/10/2023] [Accepted: 09/09/2023] [Indexed: 11/02/2023] Open
Abstract
ABSTRACT Neuroscientists have recognized the importance of astrocytes in regulating neurological function and their influence on the release of glial transmitters. Few studies, however, have focused on the effects of general anesthetic agents on neuroglia or astrocytes. Astrocytes can also be an important target of general anesthetic agents as they exert not only sedative, analgesic, and amnesic effects but also mediate general anesthetic-induced neurotoxicity and postoperative cognitive dysfunction. Here, we analyzed recent advances in understanding the mechanism of general anesthetic agents on astrocytes, and found that exposure to general anesthetic agents will destroy the morphology and proliferation of astrocytes, in addition to acting on the receptors on their surface, which not only affect Ca2+ signaling, inhibit the release of brain-derived neurotrophic factor and lactate from astrocytes, but are even involved in the regulation of the pro- and anti-inflammatory processes of astrocytes. These would obviously affect the communication between astrocytes as well as between astrocytes and neighboring neurons, other neuroglia, and vascular cells. In this review, we summarize how general anesthetic agents act on neurons via astrocytes, and explore potential mechanisms of action of general anesthetic agents on the nervous system. We hope that this review will provide a new direction for mitigating the neurotoxicity of general anesthetic agents.
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Affiliation(s)
- Yanchang Yang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Tiantian Liu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
- Department of Anesthesiology, Ningbo Women and Children’s Hospital, Ningbo, Zhejiang Province, China
| | - Jun Li
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
- Department of Anesthesiology, Shulan (Hangzhou) Hospital Affiliated to Zhejiang Shuren University Shulan International Medical College, Hangzhou, Zhejiang Province, China
| | - Dandan Yan
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Yuhan Hu
- Cell Biology Department, Yale University, New Haven, CT, USA
| | - Pin Wu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Fuquan Fang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Patrick M. McQuillan
- Department of Anesthesiology, Penn State Hershey Medical Centre, Penn State College of Medicine, Hershey, PA, USA
| | - Wenxin Hang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Jianhang Leng
- Department of Central Laboratory, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
| | - Zhiyong Hu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China
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Wilhelm M, Sych Y, Fomins A, Alatorre Warren JL, Lewis C, Serratosa Capdevila L, Boehringer R, Amadei EA, Grewe B, O'Connor EC, Hall BJ, Helmchen F. Striatum-projecting prefrontal cortex neurons support working memory maintenance. Nat Commun 2023; 14:7016. [PMID: 37919287 PMCID: PMC10622437 DOI: 10.1038/s41467-023-42777-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 10/20/2023] [Indexed: 11/04/2023] Open
Abstract
Neurons in the medial prefrontal cortex (mPFC) are functionally linked to working memory (WM) but how distinct projection pathways contribute to WM remains unclear. Based on optical recordings, optogenetic perturbations, and pharmacological interventions in male mice, we report here that dorsomedial striatum (dmStr)-projecting mPFC neurons are essential for WM maintenance, but not encoding or retrieval, in a T-maze spatial memory task. Fiber photometry of GCaMP6m-labeled mPFC→dmStr neurons revealed strongest activity during the maintenance period, and optogenetic inhibition of these neurons impaired performance only when applied during this period. Conversely, enhancing mPFC→dmStr pathway activity-via pharmacological suppression of HCN1 or by optogenetic activation during the maintenance period-alleviated WM impairment induced by NMDA receptor blockade. Moreover, cellular-resolution miniscope imaging revealed that >50% of mPFC→dmStr neurons are active during WM maintenance and that this subpopulation is distinct from neurons active during encoding and retrieval. In all task periods, neuronal sequences were evident. Striatum-projecting mPFC neurons thus critically contribute to spatial WM maintenance.
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Affiliation(s)
- Maria Wilhelm
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
- Institute for Neuroscience, ETH Zurich, 8057, Zurich, Switzerland
| | - Yaroslav Sych
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland
- Institute of Cellular and Integrative Neuroscience, CNRS, University of Strasbourg, Strasbourg, France
| | - Aleksejs Fomins
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
| | - José Luis Alatorre Warren
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland
- Center for Lifespan Changes in Brain and Cognition, University of Oslo, Oslo, 0317, Norway
| | - Christopher Lewis
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland
| | | | - Roman Boehringer
- Institute of Neuroinformatics, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
| | - Elizabeth A Amadei
- Institute of Neuroinformatics, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
| | - Benjamin Grewe
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
- Institute of Neuroinformatics, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland
- University Research Priority Program (URPP) Adaptive Brain Circuits in Development and Learning (AdaBD), University of Zurich, Zurich, Switzerland
| | - Eoin C O'Connor
- Neuroscience & Rare Diseases, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Benjamin J Hall
- Neuroscience & Rare Diseases, Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
- Circuit Biology Department, H. Lundbeck A/S, Valby, Denmark
| | - Fritjof Helmchen
- Brain Research Institute, University of Zurich, 8057, Zurich, Switzerland.
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, 8057, Zurich, Switzerland.
- University Research Priority Program (URPP) Adaptive Brain Circuits in Development and Learning (AdaBD), University of Zurich, Zurich, Switzerland.
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3
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Illes P, Ulrich H, Chen JF, Tang Y. Purinergic receptors in cognitive disturbances. Neurobiol Dis 2023; 185:106229. [PMID: 37453562 DOI: 10.1016/j.nbd.2023.106229] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/11/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023] Open
Abstract
Purinergic receptors (Rs) of the ATP/ADP, UTP/UDP (P2X, P2Y) and adenosine (A1, A2A)-sensitive classes broadly interfere with cognitive processes both under quasi normal and disease conditions. During neurodegenerative illnesses, high concentrations of ATP are released from the damaged neuronal and non-neuronal cells of the brain; then, this ATP is enzymatically degraded to adenosine. Thus, the primary injury in neurodegenerative diseases appears to be caused by various protein aggregates on which a superimposed damage mediated by especially P2X7 and A2AR activation develops; this can be efficiently prevented by small molecular antagonists in animal models of the above diseases, or are mitigated in the respective knockout mice. Dementia is a leading symptom in Alzheimer's disease (AD), and accompanies Parkinson's disease (PD) and Huntington's disease (HD), especially in the advanced states of these illnesses. Animal experimentation suggests that P2X7 and A2ARs are also involved in a number of psychiatric diseases, such as major depressive disorder (MDD), obsessive compulsive behavior, and attention deficit hyperactivity disorder. In conclusion, small molecular antagonists of purinergic receptors are expected to supply us in the future with pharmaceuticals which are able to combat in a range of neurological/psychiatric diseases the accompanying cognitive deterioration.
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Affiliation(s)
- Peter Illes
- School of Acupuncture and Tuina, Chengdu University of Traditonal Chinese Medicine, Chengdu 610075, China; Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, 04107 Leipzig, Germany; International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
| | - Henning Ulrich
- International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China; Department of Biochemistry and Molecular Biology, Chemistry Institute, University of Sao Paulo (USP), Sao Paulo, Brazil
| | - Jiang-Fan Chen
- The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center, The State Key Laboratory of Ophthalmology, Optometry and Vision Science, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Whenzhou 325000, China
| | - Yong Tang
- School of Acupuncture and Tuina, Chengdu University of Traditonal Chinese Medicine, Chengdu 610075, China; International Joint Research Center for Purinergic Signaling, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China; Acupuncture and Chronobiology Key Laboratory of Sichuan Province, School of Health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
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Kozachkov L, Kastanenka KV, Krotov D. Building transformers from neurons and astrocytes. Proc Natl Acad Sci U S A 2023; 120:e2219150120. [PMID: 37579149 PMCID: PMC10450673 DOI: 10.1073/pnas.2219150120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 06/22/2023] [Indexed: 08/16/2023] Open
Abstract
Glial cells account for between 50% and 90% of all human brain cells, and serve a variety of important developmental, structural, and metabolic functions. Recent experimental efforts suggest that astrocytes, a type of glial cell, are also directly involved in core cognitive processes such as learning and memory. While it is well established that astrocytes and neurons are connected to one another in feedback loops across many timescales and spatial scales, there is a gap in understanding the computational role of neuron-astrocyte interactions. To help bridge this gap, we draw on recent advances in AI and astrocyte imaging technology. In particular, we show that neuron-astrocyte networks can naturally perform the core computation of a Transformer, a particularly successful type of AI architecture. In doing so, we provide a concrete, normative, and experimentally testable account of neuron-astrocyte communication. Because Transformers are so successful across a wide variety of task domains, such as language, vision, and audition, our analysis may help explain the ubiquity, flexibility, and power of the brain's neuron-astrocyte networks.
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Affiliation(s)
- Leo Kozachkov
- Massachusetts Institute of Technology-International Business Machines, Watson Artificial Intelligence Laboratory, IBM Research, Cambridge, MA02142
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Ksenia V. Kastanenka
- Department of Neurology, MassGeneral Institute for Neurodegenerative Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, MA02115
| | - Dmitry Krotov
- Massachusetts Institute of Technology-International Business Machines, Watson Artificial Intelligence Laboratory, IBM Research, Cambridge, MA02142
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5
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Suthard RL, Senne RA, Buzharsky MD, Pyo AY, Dorst KE, Diep AH, Cole RH, Ramirez S. Basolateral Amygdala Astrocytes Are Engaged by the Acquisition and Expression of a Contextual Fear Memory. J Neurosci 2023; 43:4997-5013. [PMID: 37268419 PMCID: PMC10324998 DOI: 10.1523/jneurosci.1775-22.2023] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 06/04/2023] Open
Abstract
Astrocytes are key cellular regulators within the brain. The basolateral amygdala (BLA) is implicated in fear memory processing, yet most research has entirely focused on neuronal mechanisms, despite a significant body of work implicating astrocytes in learning and memory. In the present study, we used in vivo fiber photometry in C57BL/6J male mice to record from amygdalar astrocytes across fear learning, recall, and three separate periods of extinction. We found that BLA astrocytes robustly responded to foot shock during acquisition, their activity remained remarkably elevated across days in comparison to unshocked control animals, and their increased activity persisted throughout extinction. Further, we found that astrocytes responded to the initiation and termination of freezing bouts during contextual fear conditioning and recall, and this behavior-locked pattern of activity did not persist throughout the extinction sessions. Importantly, astrocytes do not display these changes while exploring a novel context, suggesting that these observations are specific to the original fear-associated environment. Chemogenetic inhibition of fear ensembles in the BLA did not affect freezing behavior or astrocytic calcium dynamics. Overall, our work presents a real-time role for amygdalar astrocytes in fear processing and provides new insight into the emerging role of these cells in cognition and behavior.SIGNIFICANCE STATEMENT We show that basolateral amygdala astrocytes are robustly responsive to negative experiences, like shock, and display changed calcium activity patterns through fear learning and memory. Additionally, astrocytic calcium responses become time locked to the initiation and termination of freezing behavior during fear learning and recall. We find that astrocytes display calcium dynamics unique to a fear-conditioned context, and chemogenetic inhibition of BLA fear ensembles does not have an impact on freezing behavior or calcium dynamics. These findings show that astrocytes play a key real-time role in fear learning and memory.
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Affiliation(s)
- Rebecca L Suthard
- Graduate Program for Neuroscience, Boston University, Boston, Massachusetts 02215
- Department of Psychological and Brain Sciences, Center for Systems Neuroscience, Neurophotonics Center, and Photonics Center, Boston University, Boston, Massachusetts 02215
| | - Ryan A Senne
- Graduate Program for Neuroscience, Boston University, Boston, Massachusetts 02215
- Department of Psychological and Brain Sciences, Center for Systems Neuroscience, Neurophotonics Center, and Photonics Center, Boston University, Boston, Massachusetts 02215
| | - Michelle D Buzharsky
- Undergraduate Program in Neuroscience, Boston University, Boston, Massachusetts 02215
| | - Angela Y Pyo
- Department of Psychological and Brain Sciences, Center for Systems Neuroscience, Neurophotonics Center, and Photonics Center, Boston University, Boston, Massachusetts 02215
| | - Kaitlyn E Dorst
- Graduate Program for Neuroscience, Boston University, Boston, Massachusetts 02215
- Department of Psychological and Brain Sciences, Center for Systems Neuroscience, Neurophotonics Center, and Photonics Center, Boston University, Boston, Massachusetts 02215
| | - Anh H Diep
- Undergraduate Program in Neuroscience, Boston University, Boston, Massachusetts 02215
| | - Rebecca H Cole
- Undergraduate Program in Neuroscience, Boston University, Boston, Massachusetts 02215
| | - Steve Ramirez
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215
- Department of Psychological and Brain Sciences, Center for Systems Neuroscience, Neurophotonics Center, and Photonics Center, Boston University, Boston, Massachusetts 02215
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6
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Ma W, Si T, Wang Z, Wen P, Zhu Z, Liu Q, Wang J, Xu F, Li Q. Astrocytic α4-containing nAChR signaling in the hippocampus governs the formation of temporal association memory. Cell Rep 2023; 42:112674. [PMID: 37352098 DOI: 10.1016/j.celrep.2023.112674] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 03/24/2023] [Accepted: 06/06/2023] [Indexed: 06/25/2023] Open
Abstract
Everyday episodic memories involve linking together related events that are temporally separated. However, the mechanisms of forming this temporal association have remained unclear. Here, using astrocyte-specific manipulations, we show that potentiating astrocyte Ca2+ signaling in the hippocampal cornu ammonis 1 (CA1) enhances the strength of such temporal association, in parallel with long-term potentiation (LTP) enhancement of temporoammonic pathway to CA1, whereas attenuation of astrocyte Ca2+ signaling has the opposite effect. Moreover, we identify that these effects are mediated by astrocytic α4 subunit-containing nicotinic acetylcholine receptors (α4-nAChRs) via mechanisms involving NMDAR co-agonist supply. Finally, astrocytic α4-nAChRs underlie the cognitive enhancer nicotine's physiological effects. Together, these findings highlight the importance of astrocyte Ca2+ signaling in cognitive behavior and reveal a mechanism in governing the temporal association of episodic memory formation that operates through α4-nAChRs on hippocampal astrocytes.
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Affiliation(s)
- Wenyu Ma
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tengxiao Si
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zan Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengjie Wen
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Zhenxiang Zhu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; Shenzhen Key Laboratory of Viral Vectors for Biomedicine, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing Liu
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fuqiang Xu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; Shenzhen Key Laboratory of Viral Vectors for Biomedicine, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Qin Li
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Multiple forms of working memory emerge from synapse-astrocyte interactions in a neuron-glia network model. Proc Natl Acad Sci U S A 2022; 119:e2207912119. [PMID: 36256810 PMCID: PMC9618090 DOI: 10.1073/pnas.2207912119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Persistent activity in populations of neurons, time-varying activity across a neural population, or activity-silent mechanisms carried out by hidden internal states of the neural population have been proposed as different mechanisms of working memory (WM). Whether these mechanisms could be mutually exclusive or occur in the same neuronal circuit remains, however, elusive, and so do their biophysical underpinnings. While WM is traditionally regarded to depend purely on neuronal mechanisms, cortical networks also include astrocytes that can modulate neural activity. We propose and investigate a network model that includes both neurons and glia and show that glia-synapse interactions can lead to multiple stable states of synaptic transmission. Depending on parameters, these interactions can lead in turn to distinct patterns of network activity that can serve as substrates for WM.
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