1
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Rupprecht P, Duss SN, Becker D, Lewis CM, Bohacek J, Helmchen F. Centripetal integration of past events in hippocampal astrocytes regulated by locus coeruleus. Nat Neurosci 2024; 27:927-939. [PMID: 38570661 PMCID: PMC11089000 DOI: 10.1038/s41593-024-01612-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 02/26/2024] [Indexed: 04/05/2024]
Abstract
An essential feature of neurons is their ability to centrally integrate information from their dendrites. The activity of astrocytes, in contrast, has been described as mostly uncoordinated across cellular compartments without clear central integration. Here we report conditional integration of calcium signals in astrocytic distal processes at their soma. In the hippocampus of adult mice of both sexes, we found that global astrocytic activity, as recorded with population calcium imaging, reflected past neuronal and behavioral events on a timescale of seconds. Salient past events, indicated by pupil dilations, facilitated the propagation of calcium signals from distal processes to the soma. Centripetal propagation to the soma was reproduced by optogenetic activation of the locus coeruleus, a key regulator of arousal, and reduced by pharmacological inhibition of α1-adrenergic receptors. Together, our results suggest that astrocytes are computational units of the brain that slowly and conditionally integrate calcium signals upon behaviorally relevant events.
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Affiliation(s)
- Peter Rupprecht
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zürich, Switzerland.
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland.
| | - Sian N Duss
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland
- Laboratory of Molecular and Behavioral Neuroscience, Institute for Neuroscience, Department of Health Sciences and Technology, ETH Zurich, Zürich, Switzerland
| | - Denise Becker
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zürich, Switzerland
| | - Christopher M Lewis
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zürich, Switzerland
| | - Johannes Bohacek
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland
- Laboratory of Molecular and Behavioral Neuroscience, Institute for Neuroscience, Department of Health Sciences and Technology, ETH Zurich, Zürich, Switzerland
| | - Fritjof Helmchen
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zürich, Switzerland.
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zürich, Switzerland.
- University Research Priority Program (URPP), Adaptive Brain Circuits in Development and Learning, University of Zurich, Zürich, Switzerland.
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2
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Cahill MK, Collard M, Tse V, Reitman ME, Etchenique R, Kirst C, Poskanzer KE. Network-level encoding of local neurotransmitters in cortical astrocytes. Nature 2024; 629:146-153. [PMID: 38632406 PMCID: PMC11062919 DOI: 10.1038/s41586-024-07311-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 03/13/2024] [Indexed: 04/19/2024]
Abstract
Astrocytes, the most abundant non-neuronal cell type in the mammalian brain, are crucial circuit components that respond to and modulate neuronal activity through calcium (Ca2+) signalling1-7. Astrocyte Ca2+ activity is highly heterogeneous and occurs across multiple spatiotemporal scales-from fast, subcellular activity3,4 to slow, synchronized activity across connected astrocyte networks8-10-to influence many processes5,7,11. However, the inputs that drive astrocyte network dynamics remain unclear. Here we used ex vivo and in vivo two-photon astrocyte imaging while mimicking neuronal neurotransmitter inputs at multiple spatiotemporal scales. We find that brief, subcellular inputs of GABA and glutamate lead to widespread, long-lasting astrocyte Ca2+ responses beyond an individual stimulated cell. Further, we find that a key subset of Ca2+ activity-propagative activity-differentiates astrocyte network responses to these two main neurotransmitters, and may influence responses to future inputs. Together, our results demonstrate that local, transient neurotransmitter inputs are encoded by broad cortical astrocyte networks over a minutes-long time course, contributing to accumulating evidence that substantial astrocyte-neuron communication occurs across slow, network-level spatiotemporal scales12-14. These findings will enable future studies to investigate the link between specific astrocyte Ca2+ activity and specific functional outputs, which could build a consistent framework for astrocytic modulation of neuronal activity.
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Affiliation(s)
- Michelle K Cahill
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA
- Neuroscience Graduate Program, University of California, San Francisco, CA, USA
| | - Max Collard
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA
- Neuroscience Graduate Program, University of California, San Francisco, CA, USA
| | - Vincent Tse
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA
| | - Michael E Reitman
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA
- Neuroscience Graduate Program, University of California, San Francisco, CA, USA
| | - Roberto Etchenique
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - Christoph Kirst
- Neuroscience Graduate Program, University of California, San Francisco, CA, USA
- Department of Anatomy, University of California, San Francisco, CA, USA
- Kavli Institute for Fundamental Neuroscience, San Francisco, CA, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kira E Poskanzer
- Department of Biochemistry & Biophysics, University of California, San Francisco, CA, USA.
- Neuroscience Graduate Program, University of California, San Francisco, CA, USA.
- Kavli Institute for Fundamental Neuroscience, San Francisco, CA, USA.
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3
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Wu Y, Dai Y, Lefton KB, Holy TE, Papouin T. STARDUST: a pipeline for the unbiased analysis of astrocyte regional calcium dynamics. bioRxiv 2024:2024.04.04.588196. [PMID: 38645020 PMCID: PMC11030233 DOI: 10.1101/2024.04.04.588196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Calcium imaging has become an increasingly popular way to probe the activity of astrocytes. However, the governing principles of astrocyte calcium dynamics are still elusive and their relationship to cellular events ill-defined. Useful assumptions and 'shortcuts' commonly applied to neuronal recordings therefore do not hold true for astrocytes. The imaging of astrocyte calcium activity per se can be relatively straightforward, subsequent analysis methods that adequately capture the richness and complexity of calcium dynamics remain scant. Here, we introduce STARDUST, a pipeline and python-based data processing for the Spatio-Temporal Analysis of Regional Dynamics & Unbiased Sorting of Transients from astrocyte calcium recordings. STARDUST builds upon AQuA to identify patches of active signals, from which it builds a data-driven map of regions of activity (ROAs) that can be combined with cell-segmentation and/or correlated to cellular morphology. For each ROA, STARDUST extracts fluorescence time-series, and performs signal identification and features extraction. STARDUST is agnostic to cell morphology (or cells altogether) and putative calcium propagation across ROAs. Instead, it focuses on decomposing calcium dynamics in a regionalized fashion by treating ROAs as independent units, for instance allowing investigations by signal feature-based ROA rank. STARDUST also identifies ROAs as "stable" (active throughout), "ON" (turned on during drug application) and "OFF" (turned off during drug application) in pharmacology experiments, permitting studies of astrocyte calcium "micro-domains" based on their functional responses. With a systematic set of instructions and troubleshooting tips, and minimal computational/coding background required, STARDUST is a user-friendly addition to the growing toolbox for the exploration of astrocyte calcium dynamics.
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Affiliation(s)
- Yifan Wu
- Washington University in St. Louis, Department of Neuroscience, St. Louis, MO 63110 USA
- Technical contact
| | - Yanchao Dai
- Washington University in St. Louis, Department of Neuroscience, St. Louis, MO 63110 USA
| | - Katheryn B. Lefton
- Washington University in St. Louis, Department of Neuroscience, St. Louis, MO 63110 USA
| | - Timothy E. Holy
- Washington University in St. Louis, Department of Neuroscience, St. Louis, MO 63110 USA
| | - Thomas Papouin
- Washington University in St. Louis, Department of Neuroscience, St. Louis, MO 63110 USA
- Lead contact
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4
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Zimmer TS, Orr AL, Orr AG. Astrocytes in selective vulnerability to neurodegenerative disease. Trends Neurosci 2024; 47:289-302. [PMID: 38521710 PMCID: PMC11006581 DOI: 10.1016/j.tins.2024.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/06/2024] [Accepted: 02/26/2024] [Indexed: 03/25/2024]
Abstract
Selective vulnerability of specific brain regions and cell populations is a hallmark of neurodegenerative disorders. Mechanisms of selective vulnerability involve neuronal heterogeneity, functional specializations, and differential sensitivities to stressors and pathogenic factors. In this review we discuss the growing body of literature suggesting that, like neurons, astrocytes are heterogeneous and specialized, respond to and integrate diverse inputs, and induce selective effects on brain function. In disease, astrocytes undergo specific, context-dependent changes that promote different pathogenic trajectories and functional outcomes. We propose that astrocytes contribute to selective vulnerability through maladaptive transitions to context-divergent phenotypes that impair specific brain regions and functions. Further studies on the multifaceted roles of astrocytes in disease may provide new therapeutic approaches to enhance resilience against neurodegenerative disorders.
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Affiliation(s)
- Till S Zimmer
- Appel Alzheimer's Disease Research Institute, Weill Cornell Medicine, New York, NY, USA; Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Adam L Orr
- Appel Alzheimer's Disease Research Institute, Weill Cornell Medicine, New York, NY, USA; Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA; Neuroscience Graduate Program, Weill Cornell Medicine, New York, NY, USA
| | - Anna G Orr
- Appel Alzheimer's Disease Research Institute, Weill Cornell Medicine, New York, NY, USA; Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA; Neuroscience Graduate Program, Weill Cornell Medicine, New York, NY, USA.
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5
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Renden RB, Institoris A, Sharma K, Tran CHT. Modulatory effects of noradrenergic and serotonergic signaling pathway on neurovascular coupling. Commun Biol 2024; 7:287. [PMID: 38459113 PMCID: PMC10923894 DOI: 10.1038/s42003-024-05996-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 02/28/2024] [Indexed: 03/10/2024] Open
Abstract
Dynamic changes in astrocyte Ca2+ are recognized as contributors to functional hyperemia, a critical response to increased neuronal activity mediated by a process known as neurovascular coupling (NVC). Although the critical role of glutamatergic signaling in this process has been extensively investigated, the impact of behavioral state, and the release of behavior-associated neurotransmitters, such as norepinephrine and serotonin, on astrocyte Ca2+ dynamics and functional hyperemia have received less attention. We used two-photon imaging of the barrel cortex in awake mice to examine the role of noradrenergic and serotonergic projections in NVC. We found that both neurotransmitters facilitated sensory stimulation-induced increases in astrocyte Ca2+. Interestingly, while ablation of serotonergic neurons reduced sensory stimulation-induced functional hyperemia, ablation of noradrenergic neurons caused both attenuation and potentiation of functional hyperemia. Our study demonstrates that norepinephrine and serotonin are involved in modulating sensory stimulation-induced astrocyte Ca2+ elevations and identifies their differential effects in regulating functional hyperemia.
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Affiliation(s)
- Robert B Renden
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada Reno, Reno, NV, USA
| | - Adam Institoris
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kushal Sharma
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada Reno, Reno, NV, USA
| | - Cam Ha T Tran
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada Reno, Reno, NV, USA.
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6
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Montalant A, Kiehn O, Perrier JF. Dopamine and noradrenaline activate spinal astrocyte endfeet via D1-like receptors. Eur J Neurosci 2024; 59:1278-1295. [PMID: 38052454 DOI: 10.1111/ejn.16205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 12/07/2023]
Abstract
Astrocytes, the most abundant glial cells in the central nervous system, respond to a wide variety of neurotransmitters binding to metabotropic receptors. Here, we investigated the intracellular calcium responses of spinal cord astrocytes to dopamine and noradrenaline, two catecholamines released by specific descending pathways. In a slice preparation from the spinal cord of neonatal mice, puff application of dopamine resulted in intracellular calcium responses that remained in the endfeet. Noradrenaline induced stronger responses that also started in the endfeet but spread to neighbouring compartments. The intracellular calcium responses were unaffected by blocking neuronal activity or inhibiting various neurotransmitter receptors, suggesting a direct effect of dopamine and noradrenaline on astrocytes. The intracellular calcium responses induced by noradrenaline and dopamine were inhibited by the D1 receptor antagonist SCH 23390. We assessed the functional consequences of these astrocytic responses by examining changes in arteriole diameter. Puff application of dopamine or noradrenaline resulted in vasoconstriction of spinal arterioles. However, blocking D1 receptors or manipulating astrocytic intracellular calcium levels did not abolish the vasoconstrictions, indicating that the observed intracellular calcium responses in astrocyte endfeet were not responsible for the vascular changes. Our findings demonstrate a compartmentalized response of spinal cord astrocytes to catecholamines and expand our understanding of astrocyte-neurotransmitter interactions and their potential roles in the physiology of the central nervous system.
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Affiliation(s)
- Alexia Montalant
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ole Kiehn
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jean-François Perrier
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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7
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Ahmadpour N, Kantroo M, Stobart MJ, Meza-Resillas J, Shabanipour S, Parra-Nuñez J, Salamovska T, Muzaleva A, O'Hara F, Erickson D, Di Gaetano B, Carrion-Falgarona S, Weber B, Lamont A, Lavine NE, Kauppinen TM, Jackson MF, Stobart JL. Cortical astrocyte N-methyl-D-aspartate receptors influence whisker barrel activity and sensory discrimination in mice. Nat Commun 2024; 15:1571. [PMID: 38383567 PMCID: PMC10882001 DOI: 10.1038/s41467-024-45989-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 02/06/2024] [Indexed: 02/23/2024] Open
Abstract
Astrocytes express ionotropic receptors, including N-methyl-D-aspartate receptors (NMDARs). However, the contribution of NMDARs to astrocyte-neuron interactions, particularly in vivo, has not been elucidated. Here we show that a knockdown approach to selectively reduce NMDARs in mouse cortical astrocytes decreases astrocyte Ca2+ transients evoked by sensory stimulation. Astrocyte NMDAR knockdown also impairs nearby neuronal circuits by elevating spontaneous neuron activity and limiting neuronal recruitment, synchronization, and adaptation during sensory stimulation. Furthermore, this compromises the optimal processing of sensory information since the sensory acuity of the mice is reduced during a whisker-dependent tactile discrimination task. Lastly, we rescue the effects of astrocyte NMDAR knockdown on neurons and improve the tactile acuity of the animal by supplying exogenous ATP. Overall, our findings show that astrocytes can respond to nearby neuronal activity via their NMDAR, and that these receptors are an important component for purinergic signaling that regulate astrocyte-neuron interactions and cortical sensory discrimination in vivo.
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Affiliation(s)
| | - Meher Kantroo
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | | | | | | | | | | | - Anna Muzaleva
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | - Finnegan O'Hara
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | - Dustin Erickson
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | - Bruno Di Gaetano
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | | | - Bruno Weber
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Alana Lamont
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
- PrairieNeuro Research Center, Health Sciences Center, Winnipeg, MB, Canada
| | - Natalie E Lavine
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
- PrairieNeuro Research Center, Health Sciences Center, Winnipeg, MB, Canada
| | - Tiina M Kauppinen
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
- PrairieNeuro Research Center, Health Sciences Center, Winnipeg, MB, Canada
| | - Michael F Jackson
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
- PrairieNeuro Research Center, Health Sciences Center, Winnipeg, MB, Canada
| | - Jillian L Stobart
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada.
- Centre on Aging, University of Manitoba, Winnipeg, MB, Canada.
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8
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Naghieh P, Delavar A, Amiri M, Peremans H. Astrocyte's self-repairing characteristics improve working memory in spiking neuronal networks. iScience 2023; 26:108241. [PMID: 38047076 PMCID: PMC10692671 DOI: 10.1016/j.isci.2023.108241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 08/23/2023] [Accepted: 10/15/2023] [Indexed: 12/05/2023] Open
Abstract
Astrocytes play a significant role in the working memory (WM) mechanism, yet their contribution to spiking neuron-astrocyte networks (SNAN) is underexplored. This study proposes a non-probabilistic SNAN incorporating a self-repairing (SR) mechanism through endocannabinoid pathways to facilitate WM function. Four experiments were conducted with different damaging patterns, replicating close-to-realistic synaptic impairments. Simulation results suggest that the SR process enhances WM performance by improving the consistency of neuronal firing. Moreover, the intercellular astrocytic [Ca]2+ transmission via gap junctions improves WM and SR processes. With increasing damage, WM and SR activities initially fail for non-matched samples and then for smaller and minimally overlapping matched samples. Simulation results also indicate that the inclusion of the SR mechanism in both random and continuous forms of damage improves the resilience of the WM by approximately 20%. This study highlights the importance of astrocytes in synaptically impaired networks.
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Affiliation(s)
- Pedram Naghieh
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Abolfazl Delavar
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mahmood Amiri
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran
- Department of Engineering Management, University of Antwerp, Antwerp, Belgium
| | - Herbert Peremans
- Department of Engineering Management, University of Antwerp, Antwerp, Belgium
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9
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Cahill MK, Collard M, Tse V, Reitman ME, Etchenique R, Kirst C, Poskanzer KE. Network-level encoding of local neurotransmitters in cortical astrocytes. bioRxiv 2023:2023.12.01.568932. [PMID: 38106119 PMCID: PMC10723263 DOI: 10.1101/2023.12.01.568932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Astrocytes-the most abundant non-neuronal cell type in the mammalian brain-are crucial circuit components that respond to and modulate neuronal activity via calcium (Ca 2+ ) signaling 1-8 . Astrocyte Ca 2+ activity is highly heterogeneous and occurs across multiple spatiotemporal scales: from fast, subcellular activity 3,4 to slow, synchronized activity that travels across connected astrocyte networks 9-11 . Furthermore, astrocyte network activity has been shown to influence a wide range of processes 5,8,12 . While astrocyte network activity has important implications for neuronal circuit function, the inputs that drive astrocyte network dynamics remain unclear. Here we used ex vivo and in vivo two-photon Ca 2+ imaging of astrocytes while mimicking neuronal neurotransmitter inputs at multiple spatiotemporal scales. We find that brief, subcellular inputs of GABA and glutamate lead to widespread, long-lasting astrocyte Ca 2+ responses beyond an individual stimulated cell. Further, we find that a key subset of Ca 2+ activity-propagative events-differentiates astrocyte network responses to these two major neurotransmitters, and gates responses to future inputs. Together, our results demonstrate that local, transient neurotransmitter inputs are encoded by broad cortical astrocyte networks over the course of minutes, contributing to accumulating evidence across multiple model organisms that significant astrocyte-neuron communication occurs across slow, network-level spatiotemporal scales 13-15 . We anticipate that this study will be a starting point for future studies investigating the link between specific astrocyte Ca 2+ activity and specific astrocyte functional outputs, which could build a consistent framework for astrocytic modulation of neuronal activity.
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10
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Abstract
The participation of astrocytes in brain computation was hypothesized in 1992, coinciding with the discovery that these cells display a form of intracellular Ca2+ signaling sensitive to neuroactive molecules. This finding fostered conceptual leaps crystalized around the idea that astrocytes, once thought to be passive, participate actively in brain signaling and outputs. A multitude of disparate roles of astrocytes has since emerged, but their meaningful integration has been muddied by the lack of consensus and models of how we conceive the functional position of these cells in brain circuitry. In this Perspective, we propose an intuitive, data-driven and transferable conceptual framework we coin 'contextual guidance'. It describes astrocytes as 'contextual gates' that shape neural circuitry in an adaptive, state-dependent fashion. This paradigm provides fresh perspectives on principles of astrocyte signaling and its relevance to brain function, which could spur new experimental avenues, including in computational space.
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Affiliation(s)
- Ciaran Murphy-Royal
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM) & Département de Neurosciences, Université de Montréal, Montréal, Quebec, Canada
| | - ShiNung Ching
- Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Thomas Papouin
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA.
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11
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Lia A, Di Spiezio A, Vitalini L, Tore M, Puja G, Losi G. Ion Channels and Ionotropic Receptors in Astrocytes: Physiological Functions and Alterations in Alzheimer's Disease and Glioblastoma. Life (Basel) 2023; 13:2038. [PMID: 37895420 PMCID: PMC10608464 DOI: 10.3390/life13102038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/03/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023] Open
Abstract
The human brain is composed of nearly one hundred billion neurons and an equal number of glial cells, including macroglia, i.e., astrocytes and oligodendrocytes, and microglia, the resident immune cells of the brain. In the last few decades, compelling evidence has revealed that glial cells are far more active and complex than previously thought. In particular, astrocytes, the most abundant glial cell population, not only take part in brain development, metabolism, and defense against pathogens and insults, but they also affect sensory, motor, and cognitive functions by constantly modulating synaptic activity. Not surprisingly, astrocytes are actively involved in neurodegenerative diseases (NDs) and other neurological disorders like brain tumors, in which they rapidly become reactive and mediate neuroinflammation. Reactive astrocytes acquire or lose specific functions that differently modulate disease progression and symptoms, including cognitive impairments. Astrocytes express several types of ion channels, including K+, Na+, and Ca2+ channels, transient receptor potential channels (TRP), aquaporins, mechanoreceptors, and anion channels, whose properties and functions are only partially understood, particularly in small processes that contact synapses. In addition, astrocytes express ionotropic receptors for several neurotransmitters. Here, we provide an extensive and up-to-date review of the roles of ion channels and ionotropic receptors in astrocyte physiology and pathology. As examples of two different brain pathologies, we focus on Alzheimer's disease (AD), one of the most diffuse neurodegenerative disorders, and glioblastoma (GBM), the most common brain tumor. Understanding how ion channels and ionotropic receptors in astrocytes participate in NDs and tumors is necessary for developing new therapeutic tools for these increasingly common neurological conditions.
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Affiliation(s)
- Annamaria Lia
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
| | - Alessandro Di Spiezio
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
- Neuroscience Institute (CNR-IN), Padova Section, 35131 Padova, Italy
| | - Lorenzo Vitalini
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Manuela Tore
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giulia Puja
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Gabriele Losi
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
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12
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de Ceglia R, Ledonne A, Litvin DG, Lind BL, Carriero G, Latagliata EC, Bindocci E, Di Castro MA, Savtchouk I, Vitali I, Ranjak A, Congiu M, Canonica T, Wisden W, Harris K, Mameli M, Mercuri N, Telley L, Volterra A. Specialized astrocytes mediate glutamatergic gliotransmission in the CNS. Nature 2023; 622:120-129. [PMID: 37674083 PMCID: PMC10550825 DOI: 10.1038/s41586-023-06502-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 07/31/2023] [Indexed: 09/08/2023]
Abstract
Multimodal astrocyte-neuron communications govern brain circuitry assembly and function1. For example, through rapid glutamate release, astrocytes can control excitability, plasticity and synchronous activity2,3 of synaptic networks, while also contributing to their dysregulation in neuropsychiatric conditions4-7. For astrocytes to communicate through fast focal glutamate release, they should possess an apparatus for Ca2+-dependent exocytosis similar to neurons8-10. However, the existence of this mechanism has been questioned11-13 owing to inconsistent data14-17 and a lack of direct supporting evidence. Here we revisited the astrocyte glutamate exocytosis hypothesis by considering the emerging molecular heterogeneity of astrocytes18-21 and using molecular, bioinformatic and imaging approaches, together with cell-specific genetic tools that interfere with glutamate exocytosis in vivo. By analysing existing single-cell RNA-sequencing databases and our patch-seq data, we identified nine molecularly distinct clusters of hippocampal astrocytes, among which we found a notable subpopulation that selectively expressed synaptic-like glutamate-release machinery and localized to discrete hippocampal sites. Using GluSnFR-based glutamate imaging22 in situ and in vivo, we identified a corresponding astrocyte subgroup that responds reliably to astrocyte-selective stimulations with subsecond glutamate release events at spatially precise hotspots, which were suppressed by astrocyte-targeted deletion of vesicular glutamate transporter 1 (VGLUT1). Furthermore, deletion of this transporter or its isoform VGLUT2 revealed specific contributions of glutamatergic astrocytes in cortico-hippocampal and nigrostriatal circuits during normal behaviour and pathological processes. By uncovering this atypical subpopulation of specialized astrocytes in the adult brain, we provide insights into the complex roles of astrocytes in central nervous system (CNS) physiology and diseases, and identify a potential therapeutic target.
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Affiliation(s)
- Roberta de Ceglia
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - Ada Ledonne
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
- Department of Experimental Neuroscience, IRCCS Santa Lucia Foundation, Rome, Italy
| | - David Gregory Litvin
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
- Wyss Center for Bio and Neuro Engineering, Campus Biotech, Geneva, Switzerland
| | - Barbara Lykke Lind
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Giovanni Carriero
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | | | - Erika Bindocci
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | | | - Iaroslav Savtchouk
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, USA
| | - Ilaria Vitali
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - Anurag Ranjak
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - Mauro Congiu
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - Tara Canonica
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - William Wisden
- Department of Life Sciences and UK Dementia Research Institute, Imperial College London, London, UK
| | - Kenneth Harris
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Manuel Mameli
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - Nicola Mercuri
- Department of Experimental Neuroscience, IRCCS Santa Lucia Foundation, Rome, Italy
- Department of Systems Medicine, University of Rome "Tor Vergata", Rome, Italy
| | - Ludovic Telley
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland.
| | - Andrea Volterra
- Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland.
- Wyss Center for Bio and Neuro Engineering, Campus Biotech, Geneva, Switzerland.
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13
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Foubert D, Cookson F, Ruthazer ES. Capturing a rising star: the emerging role of astrocytes in neural circuit wiring and plasticity-lessons from the visual system. Neurophotonics 2023; 10:044408. [PMID: 37766925 PMCID: PMC10520262 DOI: 10.1117/1.nph.10.4.044408] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/29/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023]
Abstract
The increasingly widespread use of calcium imaging to explore the nature of neuronal activity and circuits has unexpectedly revealed the ubiquitous presence and significance of astrocytic activity. Here, we present a brief review of visual system development, placing it in the context of recently identified roles of astrocytes in the modulation of neuronal responses and circuit plasticity, through their responses to sensory stimuli and the release of gliotransmitters.
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Affiliation(s)
- David Foubert
- Montreal Neurological Institute-Hospital, Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada
| | - Finnley Cookson
- Montreal Neurological Institute-Hospital, Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada
| | - Edward S. Ruthazer
- Montreal Neurological Institute-Hospital, Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada
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14
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Zhang Y, Zhang J, Wang Y, Yao J. Global trends and prospects about synaptic plasticity in Alzheimer's disease: a bibliometric analysis. Front Aging Neurosci 2023; 15:1234719. [PMID: 37731952 PMCID: PMC10508060 DOI: 10.3389/fnagi.2023.1234719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 08/23/2023] [Indexed: 09/22/2023] Open
Abstract
Background and purpose In recent years, synaptic plasticity disorders have been identified as one of the key pathogenic factors and the early pathological characteristics of Alzheimer's disease (AD). In this study, we tried to use bibliometric analysis to gain a systematic understanding about synaptic plasticity in Alzheimer's disease. Methods We extracted relevant publications from the Web of Science Core Collection (WoSCC) on August 29th, 2022. Then, we used CiteSpace, VOSviewer and other online bibliometric platforms to further analyze the obtained data. Results A total of 2,348 published articles and reviews about synaptic plasticity in AD from 2002 to 2022 were identified. During the past two decades, the overall trends of the numbers and citations of manuscripts were on the rise. The United States was the leading country with the largest number of publications which showed its crucial role in this field. The collaboration network analysis showed that the United States and China had the most frequent collaboration. In addition, Harvard University was the institution with the greatest number of publications and cited times. Among all authors, Selkoe DJ was the most influential author with the greatest cited times. The journal of Alzheimer's disease published the maximum number of documents in the field of synaptic plasticity in AD within 20 years. Furthermore, the results of keywords burst detection showed that the hot topics have shifted from the synaptic transmission, precursor protein and plaque formation to neuroinflammation, microglia and alpha synuclein. Conclusion This study analyzed 2,348 publications with 82,025 references covering the topic of synaptic plasticity in AD and presented the research trends. The results indicated that neuroinflammation, microglia and alpha synuclein were the current research hotspots, which implied the potential clinical applications to AD.
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Affiliation(s)
- Yingying Zhang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junyao Zhang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yinuo Wang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junyan Yao
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Anesthesiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
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15
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Kelly P, Sanchez-Mico MV, Hou SS, Whiteman S, Russ A, Hudry E, Arbel-Ornath M, Greenberg SM, Bacskai BJ. Neuronally Derived Soluble Abeta Evokes Cell-Wide Astrocytic Calcium Dysregulation in Absence of Amyloid Plaques in Vivo. J Neurosci 2023; 43:4926-4940. [PMID: 37236808 PMCID: PMC10312057 DOI: 10.1523/jneurosci.1988-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 03/22/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
The key pathologic entities driving the destruction of synaptic function and integrity during the evolution of Alzheimer's disease (AD) remain elusive. Astrocytes are structurally and functionally integrated within synaptic and vascular circuitry and use calcium-based physiology to modulate basal synaptic transmission, vascular dynamics, and neurovascular coupling, which are central to AD pathogenesis. We used high-resolution multiphoton imaging to quantify all endogenous calcium signaling arising spontaneously throughout astrocytic somata, primary processes, fine processes, and capillary endfeet in the brain of awake APP/PS1 transgenic mice (11 male and 6 female mice). Endogenous calcium signaling within capillary endfeet, while surprisingly as active as astrocytic fine processes, was reduced ∼50% in the brain of awake APP/PS1 mice. Cortical astrocytes, in the presence of amyloid plaques in awake APP/PS1 mice, had a cell-wide increase in intracellular calcium associated with an increased frequency, amplitude, and duration of spontaneous calcium signaling. The cell-wide astrocytic calcium dysregulation was not directly related to distance to amyloid plaques. We could re-create the cell-wide intracellular calcium dysregulation in the absence of amyloid plaques following acute exposure to neuronally derived soluble Abeta from Tg2576 transgenic mice, in the living brain of male C57/Bl6 mice. Our findings highlight a role for astrocytic calcium pathophysiology in soluble-Abeta mediated neurodegenerative processes in AD. Additionally, therapeutic strategies aiming to protect astrocytic calcium physiology from soluble Abeta-mediated toxicity may need to pharmacologically enhance calcium signaling within the hypoactive capillary endfeet while reducing the hyperactivity of spontaneous calcium signaling throughout the rest of the astrocyte.SIGNIFICANCE STATEMENT Astrocytic calcium signaling is functionally involved in central pathologic processes of Alzheimer's disease. We quantified endogenous calcium signaling arising spontaneously in the brain of awake APP/PS1 mice, as general anesthesia suppressed astrocytic calcium signaling. Cell-wide astrocytic calcium dysregulation was not related to distance to amyloid plaques but mediated in part by neuronally derived soluble Abeta, supporting a role for astrocytes in soluble-Abeta mediated neurodegeneration. Spontaneous calcium signaling is largely compartmentalized and capillary endfeet were as active as fine processes but hypoactive in the presence of amyloid plaques, while the rest of the astrocyte became hyperactive. The cell-wide calcium pathophysiology in astrocytes may require a combination therapeutic strategy for hypoactive endfeet and astrocytic hyperactivity.
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Affiliation(s)
- Patricia Kelly
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Maria V Sanchez-Mico
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Steven S Hou
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Sara Whiteman
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Alyssa Russ
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Eloise Hudry
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Michal Arbel-Ornath
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Steven M Greenberg
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
| | - Brian J Bacskai
- Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129
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16
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Lin J, Cheng X, Wang H, Du L, Li X, Zhao G, Xie C. Activation of astrocytes in the basal forebrain in mice facilitates isoflurane-induced loss of consciousness and prolongs recovery. BMC Anesthesiol 2023; 23:213. [PMID: 37340348 DOI: 10.1186/s12871-023-02166-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 06/06/2023] [Indexed: 06/22/2023] Open
Abstract
OBJECTIVES General anesthesia results in a state of unconsciousness that is similar to sleep. In recent years, increasing evidence has reported that astrocytes play a crucial role in regulating sleep. However, whether astrocytes are involved in general anesthesia is unknown. METHODS In the present study, the designer receptors exclusively activated by designer drugs (DREADDs) approach was utilized to specifically activate astrocytes in the basal forebrain (BF) and observed its effect on isoflurane anesthesia. One the other side, L-α-aminoadipic acid was used to selectively inhibit astrocytes in the BF and investigated its influence on isoflurane-induced hypnotic effect. During the anesthesia experiment, cortical electroencephalography (EEG) signals were recorded as well. RESULTS The chemogenetic activation group had a significantly shorter isoflurane induction time, longer recovery time, and higher delta power of EEG during anesthesia maintenance and recovery periods than the control group. Inhibition of astrocytes in the BF delayed isoflurane-induced loss of consciousness, promoted recovery, decreased delta power and increased beta and gamma power during maintenance and recovery periods. CONCLUSIONS The present study suggests that astrocytes in the BF region are involved in isoflurane anesthesia and may be a potential target for regulating the consciousness state of anesthesia.
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Affiliation(s)
- Jialing Lin
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China
| | - Xuefeng Cheng
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China
| | - Haoyuan Wang
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China
| | - Lin Du
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China
| | - Xiangyu Li
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China
| | - Gaofeng Zhao
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China.
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China.
| | - Chuangbo Xie
- Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou City, 510120, People's Republic of China.
- South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou City, Guangdong Province, 510120, People's Republic of China.
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17
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Cervetto C, Maura G, Guidolin D, Amato S, Ceccoli C, Agnati LF, Marcoli M. Striatal astrocytic A2A-D2 receptor-receptor interactions and their role in neuropsychiatric disorders. Neuropharmacology 2023:109636. [PMID: 37321323 DOI: 10.1016/j.neuropharm.2023.109636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/26/2023] [Accepted: 06/11/2023] [Indexed: 06/17/2023]
Abstract
It is now generally accepted that astrocytes are active players in synaptic transmission, so that a neurocentric perspective of the integrative signal communication in the central nervous system is shifting towards a neuro-astrocentric perspective. Astrocytes respond to synaptic activity, release chemical signals (gliotransmitters) and express neurotransmitter receptors (G protein-coupled and ionotropic receptors), thus behaving as co-actors with neurons in signal communication in the central nervous system. The ability of G protein-coupled receptors to physically interact through heteromerization, forming heteromers and receptor mosaics with new distinct signal recognition and transduction pathways, has been intensively studied at neuronal plasma membrane, and has changed the view of the integrative signal communication in the central nervous system. One of the best-known examples of receptor-receptor interaction through heteromerization, with relevant consequences for both the physiological and the pharmacological points of view, is given by adenosine A2A and dopamine D2 receptors on the plasma membrane of striatal neurons. Here we review evidence that native A2A and D2 receptors can interact through heteromerization at the plasma membrane of astrocytes as well. Astrocytic A2A-D2 heteromers were found able to control the release of glutamate from the striatal astrocyte processes. A2A-D2 heteromers on striatal astrocytes and astrocyte processes are discussed as far as their potential relevance in the control of glutamatergic transmission in striatum is concerned, including potential roles in glutamatergic transmission dysregulation in pathological conditions including schizophrenia or the Parkinson's disease.
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Affiliation(s)
- Chiara Cervetto
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy; Center for Promotion of 3Rs in Teaching and Research (Centro 3R), Pisa, Italy.
| | - Guido Maura
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy.
| | - Diego Guidolin
- Department of Neuroscience, University of Padova, Italy.
| | - Sarah Amato
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy.
| | - Cristina Ceccoli
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy.
| | - Luigi F Agnati
- Department of Biochemical, Metabolic Sciences and Neuroscience, University of Modena and Reggio Emilia, Modena, Italy.
| | - Manuela Marcoli
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy; Center for Promotion of 3Rs in Teaching and Research (Centro 3R), Pisa, Italy; Center of Excellence for Biomedical Research, University of Genova, Italy.
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18
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Prokhorenko MA, Smyth JT. Astrocyte store-operated calcium entry is required for centrally mediated neuropathic pain. bioRxiv 2023:2023.06.08.544231. [PMID: 37333230 PMCID: PMC10274864 DOI: 10.1101/2023.06.08.544231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Central sensitization is a critical step in chronic neuropathic pain formation following acute nerve injury. Central sensitization is defined by nociceptive and somatosensory circuitry changes in the spinal cord leading to dysfunction of antinociceptive gamma-aminobutyric acid (GABA)ergic cells (Li et al., 2019), amplification of ascending nociceptive signals, and hypersensitivity (Woolf, 2011). Astrocytes are key mediators of the neurocircuitry changes that underlie central sensitization and neuropathic pain, and astrocytes respond to and regulate neuronal function through complex Ca2+ signaling mechanisms. Clear definition of the astrocyte Ca2+ signaling mechanisms involved in central sensitization may lead to new therapeutic targets for treatment of chronic neuropathic pain, as well as enhance our understanding of the complex central nervous system (CNS) adaptions that occur following nerve injury. Ca2+ release from astrocyte endoplasmic reticulum (ER) Ca2+ stores via the inositol 1,4,5-trisphosphate receptor (IP3R) is required for centrally mediated neuropathic pain (Kim et al, 2016); however recent evidence suggests the involvement of additional astrocyte Ca2+ signaling mechanisms. We therefore investigated the role of astrocyte store-operated Ca2+ entry (SOCE), which mediates Ca2+ influx in response to ER Ca2+ store depletion. Using an adult Drosophila melanogaster model of central sensitization based on thermal allodynia in response to leg amputation nerve injury (Khuong et al., 2019), we show that astrocytes exhibit SOCE-dependent Ca2+ signaling events three to four days following nerve injury. Astrocyte-specific suppression of Stim and Orai, the key mediators of SOCE Ca2+ influx, completely inhibited the development of thermal allodynia seven days following injury, and also inhibited the loss of ventral nerve cord (VNC) GABAergic neurons that is required for central sensitization in flies. We lastly show that constitutive SOCE in astrocytes results in thermal allodynia even in the absence of nerve injury. Our results collectively demonstrate that astrocyte SOCE is necessary and sufficient for central sensitization and development of hypersensitivity in Drosophila, adding key new understanding to the astrocyte Ca2+ signaling mechanisms involved in chronic pain.
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Affiliation(s)
- Mariya A. Prokhorenko
- Neuroscience Graduate Program and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Jeremy T. Smyth
- Neuroscience Graduate Program and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD
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19
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Andrade-Talavera Y, Fisahn A, Rodríguez-Moreno A. Timing to be precise? An overview of spike timing-dependent plasticity, brain rhythmicity, and glial cells interplay within neuronal circuits. Mol Psychiatry 2023; 28:2177-2188. [PMID: 36991134 PMCID: PMC10611582 DOI: 10.1038/s41380-023-02027-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/31/2023]
Abstract
In the mammalian brain information processing and storage rely on the complex coding and decoding events performed by neuronal networks. These actions are based on the computational ability of neurons and their functional engagement in neuronal assemblies where precise timing of action potential firing is crucial. Neuronal circuits manage a myriad of spatially and temporally overlapping inputs to compute specific outputs that are proposed to underly memory traces formation, sensory perception, and cognitive behaviors. Spike-timing-dependent plasticity (STDP) and electrical brain rhythms are suggested to underlie such functions while the physiological evidence of assembly structures and mechanisms driving both processes continues to be scarce. Here, we review foundational and current evidence on timing precision and cooperative neuronal electrical activity driving STDP and brain rhythms, their interactions, and the emerging role of glial cells in such processes. We also provide an overview of their cognitive correlates and discuss current limitations and controversies, future perspectives on experimental approaches, and their application in humans.
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Affiliation(s)
- Yuniesky Andrade-Talavera
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cell Biology, Universidad Pablo de Olavide, ES-41013, Seville, Spain.
| | - André Fisahn
- Department of Biosciences and Nutrition and Department of Women's and Children's Health, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Antonio Rodríguez-Moreno
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cell Biology, Universidad Pablo de Olavide, ES-41013, Seville, Spain.
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20
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Bonato J, Curreli S, Romanzi S, Panzeri S, Fellin T. ASTRA: a deep learning algorithm for fast semantic segmentation of large-scale astrocytic networks. bioRxiv 2023:2023.05.03.539211. [PMID: 37205519 PMCID: PMC10187152 DOI: 10.1101/2023.05.03.539211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Changes in the intracellular calcium concentration are a fundamental fingerprint of astrocytes, the main type of glial cell. Astrocyte calcium signals can be measured with two-photon microscopy, occur in anatomically restricted subcellular regions, and are coordinated across astrocytic networks. However, current analytical tools to identify the astrocytic subcellular regions where calcium signals occur are time-consuming and extensively rely on user-defined parameters. These limitations limit reproducibility and prevent scalability to large datasets and fields-of-view. Here, we present Astrocytic calcium Spatio-Temporal Rapid Analysis (ASTRA), a novel software combining deep learning with image feature engineering for fast and fully automated semantic segmentation of two-photon calcium imaging recordings of astrocytes. We applied ASTRA to several two-photon microscopy datasets and found that ASTRA performed rapid detection and segmentation of astrocytic cell somata and processes with performance close to that of human experts, outperformed state-of-the-art algorithms for the analysis of astrocytic and neuronal calcium data, and generalized across indicators and acquisition parameters. We also applied ASTRA to the first report of two-photon mesoscopic imaging of hundreds of astrocytes in awake mice, documenting large-scale redundant and synergistic interactions in extended astrocytic networks. ASTRA is a powerful tool enabling closed-loop and large-scale reproducible investigation of astrocytic morphology and function.
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Affiliation(s)
- Jacopo Bonato
- Neural Coding Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- Department of Pharmacy and Biotechnology, University of Bologna; 40126 Bologna, Italy
- Department of Excellence for Neural Information Processing, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, D-20251 Hamburg, Germany
| | - Sebastiano Curreli
- Neural Coding Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
| | - Sara Romanzi
- Neural Coding Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- University of Genova; 16126 Genova, Italy
| | - Stefano Panzeri
- Neural Coding Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- Department of Excellence for Neural Information Processing, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, D-20251 Hamburg, Germany
| | - Tommaso Fellin
- Neural Coding Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia; 16163 Genova, Italy
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21
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Delgado L, Navarrete M. Shining the Light on Astrocytic Ensembles. Cells 2023; 12:1253. [PMID: 37174653 PMCID: PMC10177371 DOI: 10.3390/cells12091253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
While neurons have traditionally been considered the primary players in information processing, the role of astrocytes in this mechanism has largely been overlooked due to experimental constraints. In this review, we propose that astrocytic ensembles are active working groups that contribute significantly to animal conduct and suggest that studying the maps of these ensembles in conjunction with neurons is crucial for a more comprehensive understanding of behavior. We also discuss available methods for studying astrocytes and argue that these ensembles, complementarily with neurons, code and integrate complex behaviors, potentially specializing in concrete functions.
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Affiliation(s)
| | - Marta Navarrete
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), 28002 Madrid, Spain
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22
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Wang F, Wang W, Gu S, Qi D, Smith NA, Peng W, Dong W, Yuan J, Zhao B, Mao Y, Cao P, Lu QR, Shapiro LA, Yi SS, Wu E, Huang JH. Distinct astrocytic modulatory roles in sensory transmission during sleep, wakefulness, and arousal states in freely moving mice. Nat Commun 2023; 14:2186. [PMID: 37069258 PMCID: PMC10110578 DOI: 10.1038/s41467-023-37974-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/04/2023] [Indexed: 04/19/2023] Open
Abstract
Despite extensive research on astrocytic Ca2+ in synaptic transmission, its contribution to the modulation of sensory transmission during different brain states remains largely unknown. Here, by using two-photon microscopy and whole-cell recordings, we show two distinct astrocytic Ca2+ signals in the murine barrel cortex: a small, long-lasting Ca2+ increase during sleep and a large, widespread but short-lasting Ca2+ spike when aroused. The large Ca2+ wave in aroused mice was inositol trisphosphate (IP3)-dependent, evoked by the locus coeruleus-norepinephrine system, and enhanced sensory input, contributing to reliable sensory transmission. However, the small Ca2+ transient was IP3-independent and contributed to decreased extracellular K+, hyperpolarization of the neurons, and suppression of sensory transmission. These events respond to different pharmacological inputs and contribute to distinct sleep and arousal functions by modulating the efficacy of sensory transmission. Together, our data demonstrate an important function for astrocytes in sleep and arousal states via astrocytic Ca2+ waves.
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Affiliation(s)
- Fushun Wang
- Institute of Brain and Psychological Sciences, Sichuan Normal University, Chengdu, Sichuan, 610060, China.
- Department of Neurosurgery, University of Rochester, Rochester, NY, 14643, USA.
| | - Wei Wang
- Institute of Brain and Psychological Sciences, Sichuan Normal University, Chengdu, Sichuan, 610060, China
- Department of Biology, Boston University, Boston, MA, 02215, USA
| | - Simeng Gu
- Institute of Brain and Psychological Sciences, Sichuan Normal University, Chengdu, Sichuan, 610060, China
- Department of Medical Psychology, Jiangsu University Medical School, Zhenjiang, 212013, China
| | - Dan Qi
- Department of Neurosurgery and Neuroscience Institute, Baylor Scott & White Health, Temple, TX, 76508, USA
| | - Nathan A Smith
- Department of Neurosurgery, University of Rochester, Rochester, NY, 14643, USA
- George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, Washington, DC, 20010, USA
| | - Weiguo Peng
- Institute of Brain and Psychological Sciences, Sichuan Normal University, Chengdu, Sichuan, 610060, China
| | - Wei Dong
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, 646000, China
| | - Jiajin Yuan
- Department of Neurosurgery, University of Rochester, Rochester, NY, 14643, USA
| | - Binbin Zhao
- Basic Medicine College, Hubei University of Chinese Medicine, Wuhan, China
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Peng Cao
- School of Psychology, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Qing Richard Lu
- Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA
| | - Lee A Shapiro
- Department of Neuroscience & Experimental Therapeutics, Texas A&M University, Bryan, TX, 77807, USA.
| | - S Stephen Yi
- Livestrong Cancer Institutes and Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA.
- Oden Institute for Computational Engineering and Sciences (ICES), The University of Texas at Austin, Austin, TX, 78712, USA.
- Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, 78712, USA.
| | - Erxi Wu
- Department of Neurosurgery and Neuroscience Institute, Baylor Scott & White Health, Temple, TX, 76508, USA.
- Livestrong Cancer Institutes and Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA.
- Texas A & M University Health Science Center, College Station, TX, 77843, USA.
| | - Jason H Huang
- Department of Neurosurgery and Neuroscience Institute, Baylor Scott & White Health, Temple, TX, 76508, USA.
- Texas A & M University Health Science Center, College Station, TX, 77843, USA.
- Department of Neurosurgery, Baylor College of Medicine, Temple, TX, 76508, USA.
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23
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Lim D, Tapella L, Dematteis G, Talmon M, Genazzani AA. Calcineurin Signalling in Astrocytes: From Pathology to Physiology and Control of Neuronal Functions. Neurochem Res 2023; 48:1077-1090. [PMID: 36083398 PMCID: PMC10030417 DOI: 10.1007/s11064-022-03744-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 07/31/2022] [Accepted: 08/29/2022] [Indexed: 10/14/2022]
Abstract
Calcineurin (CaN), a Ca2+/calmodulin-activated serine/threonine phosphatase, acts as a Ca2+-sensitive switch regulating cellular functions through protein dephosphorylation and activation of gene transcription. In astrocytes, the principal homeostatic cells in the CNS, over-activation of CaN is known to drive pathological transcriptional remodelling, associated with neuroinflammation in diseases such as Alzheimer's disease, epilepsy and brain trauma. Recent reports suggest that, in physiological conditions, the activity of CaN in astrocytes is transcription-independent and is required for maintenance of basal protein synthesis rate and activation of astrocytic Na+/K+ pump thereby contributing to neuronal functions such as neuronal excitability and memory formation. In this contribution we overview the role of Ca2+ and CaN signalling in astroglial pathophysiology focusing on the emerging physiological role of CaN in astrocytes. We propose a model for the context-dependent switch of CaN activity from the post-transcriptional regulation of cell proteostasis in healthy astrocytes to the CaN-dependent transcriptional activation in neuroinflammation-associated diseases.
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Affiliation(s)
- Dmitry Lim
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale "Amedeo Avogadro", Via Bovio 6, 28100, Novara, Italy.
| | - Laura Tapella
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale "Amedeo Avogadro", Via Bovio 6, 28100, Novara, Italy
| | - Giulia Dematteis
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale "Amedeo Avogadro", Via Bovio 6, 28100, Novara, Italy
| | - Maria Talmon
- Department of Health Sciences, School of Medicine, Università del Piemonte Orientale "Amedeo Avogadro", Via Solaroli 17, 28100, Novara, Italy
| | - Armando A Genazzani
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale "Amedeo Avogadro", Via Bovio 6, 28100, Novara, Italy.
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24
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Lee SH, Mak A, Verheijen MHG. Comparative assessment of the effects of DREADDs and endogenously expressed GPCRs in hippocampal astrocytes on synaptic activity and memory. Front Cell Neurosci 2023; 17:1159756. [PMID: 37051110 PMCID: PMC10083367 DOI: 10.3389/fncel.2023.1159756] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 03/13/2023] [Indexed: 03/29/2023] Open
Abstract
Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) have proven themselves as one of the key in vivo techniques of modern neuroscience, allowing for unprecedented access to cellular manipulations in living animals. With respect to astrocyte research, DREADDs have become a popular method to examine the functional aspects of astrocyte activity, particularly G-protein coupled receptor (GPCR)-mediated intracellular calcium (Ca2+) and cyclic adenosine monophosphate (cAMP) dynamics. With this method it has become possible to directly link the physiological aspects of astrocytic function to cognitive processes such as memory. As a result, a multitude of studies have explored the impact of DREADD activation in astrocytes on synaptic activity and memory. However, the emergence of varying results prompts us to reconsider the degree to which DREADDs expressed in astrocytes accurately mimic endogenous GPCR activity. Here we compare the major downstream signaling mechanisms, synaptic, and behavioral effects of stimulating Gq-, Gs-, and Gi-DREADDs in hippocampal astrocytes of adult mice to those of endogenously expressed GPCRs.
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Affiliation(s)
- Sophie H. Lee
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Research Master’s Programme Brain and Cognitive Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Aline Mak
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Mark H. G. Verheijen
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- *Correspondence: Mark Verheijen,
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25
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Lia A, Sansevero G, Chiavegato A, Sbrissa M, Pendin D, Mariotti L, Pozzan T, Berardi N, Carmignoto G, Fasolato C, Zonta M. Rescue of astrocyte activity by the calcium sensor STIM1 restores long-term synaptic plasticity in female mice modelling Alzheimer's disease. Nat Commun 2023; 14:1590. [PMID: 36949142 PMCID: PMC10033875 DOI: 10.1038/s41467-023-37240-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 03/09/2023] [Indexed: 03/24/2023] Open
Abstract
Calcium dynamics in astrocytes represent a fundamental signal that through gliotransmitter release regulates synaptic plasticity and behaviour. Here we present a longitudinal study in the PS2APP mouse model of Alzheimer's disease (AD) linking astrocyte Ca2+ hypoactivity to memory loss. At the onset of plaque deposition, somatosensory cortical astrocytes of AD female mice exhibit a drastic reduction of Ca2+ signaling, closely associated with decreased endoplasmic reticulum Ca2+ concentration and reduced expression of the Ca2+ sensor STIM1. In parallel, astrocyte-dependent long-term synaptic plasticity declines in the somatosensory circuitry, anticipating specific tactile memory loss. Notably, we show that both astrocyte Ca2+ signaling and long-term synaptic plasticity are fully recovered by selective STIM1 overexpression in astrocytes. Our data unveil astrocyte Ca2+ hypoactivity in neocortical astrocytes as a functional hallmark of early AD stages and indicate astrocytic STIM1 as a target to rescue memory deficits.
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Affiliation(s)
- Annamaria Lia
- Neuroscience Institute, National Research Council (CNR), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Gabriele Sansevero
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
- Department of NEUROFARBA, University of Florence, Florence, Italy
| | - Angela Chiavegato
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Miriana Sbrissa
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Diana Pendin
- Neuroscience Institute, National Research Council (CNR), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Letizia Mariotti
- Neuroscience Institute, National Research Council (CNR), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Tullio Pozzan
- Neuroscience Institute, National Research Council (CNR), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
- Veneto Institute of Molecular Medicine, Foundation for Advanced Biomedical Research, Padua, Italy
| | - Nicoletta Berardi
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy
- Department of NEUROFARBA, University of Florence, Florence, Italy
| | - Giorgio Carmignoto
- Neuroscience Institute, National Research Council (CNR), Padua, Italy.
- Department of Biomedical Sciences, University of Padua, Padua, Italy.
| | - Cristina Fasolato
- Department of Biomedical Sciences, University of Padua, Padua, Italy.
| | - Micaela Zonta
- Neuroscience Institute, National Research Council (CNR), Padua, Italy.
- Department of Biomedical Sciences, University of Padua, Padua, Italy.
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26
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Morita M. Modern Microscopic Approaches to Astrocytes. Int J Mol Sci 2023; 24:ijms24065883. [PMID: 36982958 PMCID: PMC10051528 DOI: 10.3390/ijms24065883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/08/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
Microscopy started as the histological analysis based on intrinsic optical properties of tissues such as the refractive index and light absorption, and is expanding to include the visualization of organelles by chemical staining, localization of molecules by immunostaining, physiological measurements such as Ca2+ imaging, functional manipulation by optogenetics, and comprehensive analysis of chemical composition by Raman spectra. The microscope is one of the most important tools in neuroscience, which aims to reveal the complex intercellular communications underlying brain function and pathology. Many aspects of astrocytes, including the structures of their fine processes and physiological activities in concert with neurons and blood vessels, were revealed in the course of innovations in modern microscopy. The evolution of modern microscopy is a consequence of breakthroughs in spatiotemporal resolutions and expansions in molecular and physiological targets due to the progress in optics and information technology, as well as the inventions of probes using organic chemistry and molecular biology. This review overviews the modern microscopic approach to astrocytes.
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Affiliation(s)
- Mitsuhiro Morita
- Department of Biology, Graduate School of Sciences, Kobe University, Kobe 657-8501, Japan
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27
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Holt MG. Astrocyte heterogeneity and interactions with local neural circuits. Essays Biochem 2023; 67:93-106. [PMID: 36748397 DOI: 10.1042/EBC20220136] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/09/2023] [Accepted: 01/09/2023] [Indexed: 02/08/2023]
Abstract
Astrocytes are ubiquitous within the central nervous system (CNS). These cells possess many individual processes which extend out into the neuropil, where they interact with a variety of other cell types, including neurons at synapses. Astrocytes are now known to be active players in all aspects of the synaptic life cycle, including synapse formation and elimination, synapse maturation, maintenance of synaptic homeostasis and modulation of synaptic transmission. Traditionally, astrocytes have been studied as a homogeneous group of cells. However, recent studies have uncovered a surprising degree of heterogeneity in their development and function, suggesting that astrocytes may be matched to neurons to support local circuits. Hence, a better understanding of astrocyte heterogeneity and its implications are needed to understand brain function.
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28
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Ezkurdia A, Ramírez MJ, Solas M. Metabolic Syndrome as a Risk Factor for Alzheimer's Disease: A Focus on Insulin Resistance. Int J Mol Sci 2023; 24:ijms24054354. [PMID: 36901787 PMCID: PMC10001958 DOI: 10.3390/ijms24054354] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 02/25/2023] Open
Abstract
Alzheimer's disease (AD) is the main type of dementia and is a disease with a profound socioeconomic burden due to the lack of effective treatment. In addition to genetics and environmental factors, AD is highly associated with metabolic syndrome, defined as the combination of hypertension, hyperlipidemia, obesity and type 2 diabetes mellitus (T2DM). Among these risk factors, the connection between AD and T2DM has been deeply studied. It has been suggested that the mechanism linking both conditions is insulin resistance. Insulin is an important hormone that regulates not only peripheral energy homeostasis but also brain functions, such as cognition. Insulin desensitization, therefore, could impact normal brain function increasing the risk of developing neurodegenerative disorders in later life. Paradoxically, it has been demonstrated that decreased neuronal insulin signalling can also have a protective role in aging and protein-aggregation-associated diseases, as is the case in AD. This controversy is fed by studies focused on neuronal insulin signalling. However, the role of insulin action on other brain cell types, such as astrocytes, is still unexplored. Therefore, it is worthwhile exploring the involvement of the astrocytic insulin receptor in cognition, as well as in the onset and/or development of AD.
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Affiliation(s)
- Amaia Ezkurdia
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
- IdISNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
| | - María J. Ramírez
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
- IdISNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
| | - Maite Solas
- Department of Pharmacology and Toxicology, University of Navarra, 31008 Pamplona, Spain
- IdISNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
- Correspondence:
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29
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Liu L, Gao H, Li J, Chen S. Probing microdomain Ca 2+ activity and synaptic transmission with a node-based tripartite synapse model. Front Netw Physiol 2023; 3:1111306. [PMID: 36926546 PMCID: PMC10013067 DOI: 10.3389/fnetp.2023.1111306] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/27/2023] [Indexed: 06/08/2023]
Abstract
Astrocytic fine processes are the most minor structures of astrocytes but host much of the Ca2+ activity. These localized Ca2+ signals spatially restricted to microdomains are crucial for information processing and synaptic transmission. However, the mechanistic link between astrocytic nanoscale processes and microdomain Ca2+ activity remains hazily understood because of the technical difficulties in accessing this structurally unresolved region. In this study, we used computational models to disentangle the intricate relations of morphology and local Ca2+ dynamics involved in astrocytic fine processes. We aimed to answer: 1) how nano-morphology affects local Ca2+ activity and synaptic transmission, 2) and how fine processes affect Ca2+ activity of large process they connect. To address these issues, we undertook the following two computational modeling: 1) we integrated the in vivo astrocyte morphological data from a recent study performed with super-resolution microscopy that discriminates sub-compartments of various shapes, referred to as nodes and shafts to a classic IP3R-mediated Ca2+ signaling framework describing the intracellular Ca2+ dynamics, 2) we proposed a node-based tripartite synapse model linking with astrocytic morphology to predict the effect of structural deficits of astrocytes on synaptic transmission. Extensive simulations provided us with several biological insights: 1) the width of nodes and shafts could strongly influence the spatiotemporal variability of Ca2+ signals properties but what indeed determined the Ca2+ activity was the width ratio between nodes and shafts, 2) the connectivity of nodes to larger processes markedly shaped the Ca2+ signal of the parent process rather than nodes morphology itself, 3) the morphological changes of astrocytic part might potentially induce the abnormality of synaptic transmission by affecting the level of glutamate at tripartite synapses. Taken together, this comprehensive model which integrated theoretical computation and in vivo morphological data highlights the role of the nanomorphology of astrocytes in signal transmission and its possible mechanisms related to pathological conditions.
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Affiliation(s)
- Langzhou Liu
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
| | - Huayi Gao
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
| | - Jinyu Li
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
| | - Shangbin Chen
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
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30
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Kuroda T, Matsuda N, Ishibashi Y, Suzuki I. Detection of astrocytic slow oscillatory activity and response to seizurogenic compounds using planar microelectrode array. Front Neurosci 2023; 16:1050150. [PMID: 36703996 PMCID: PMC9872017 DOI: 10.3389/fnins.2022.1050150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/14/2022] [Indexed: 01/12/2023] Open
Abstract
Since the development of the planar microelectrode array (MEA), it has become popular to evaluate compounds based on the electrical activity of rodent and human induced pluripotent stem cell (iPSC)-derived neurons. However, there are no reports recording spontaneous human astrocyte activity from astrocyte-only culture sample by MEA. It is becoming clear that astrocytes play an important role in various neurological diseases, and astrocytes are expected to be excellent candidates for targeted therapeutics for the treatment of neurological diseases. Therefore, measuring astrocyte activity is very important for drug development for astrocytes. Recently, astrocyte activity has been found to be reflected in the low-frequency band < 1 Hz, which is much lower than the frequency band for recording neural activity. Here, we separated the signals obtained from human primary astrocytes cultured on MEA into seven frequency bands and successfully recorded the extracellular electrical activity of human astrocytes. The slow waveforms of spontaneous astrocyte activity were observed most clearly in direct current potentials < 1 Hz. We established nine parameters to assess astrocyte activity and evaluated five seizurogenic drug responses in human primary astrocytes and human iPSC-derived astrocytes. Astrocytes demonstrated the most significant dose-dependent changes in pilocarpine. Furthermore, in a principal component analysis using those parameter sets, the drug responses to each seizurogenic compound were separated. In this paper, we report the spontaneous electrical activity measurement of astrocytes alone using MEA for the first time and propose that the MEA measurement focusing on the low-frequency band could be useful as one of the methods to assess drug response in vitro.
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31
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Jiménez-Díaz E, Del-Rio D, Fiordelisio T. The Contribution of Cell Imaging to the Study of Anterior Pituitary Function and Its Regulation. Neuroendocrinology 2023; 113:179-192. [PMID: 35231920 DOI: 10.1159/000523860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 02/18/2022] [Indexed: 11/19/2022]
Abstract
Advances in the knowledge of the neuroendocrine system are closely related to the development of cellular imaging and labeling techniques. This synergy ranges from the staining techniques that allowed the first characterizations of the anterior pituitary gland, its relationship with the hypothalamus, and the birth of neuroendocrinology; through the development of fluorescence microscopy applications, specific labeling strategies, transgenic systems, and intracellular calcium sensors that enabled the study of processes and dynamics at the cellular and tissue level; until the advent of super-resolution microscopy, miniscopes, optogenetics, fiber photometry, and other imaging methods that allowed high spatiotemporal resolution and long-term three-dimensional cellular activity recordings in living systems in a conscious and freely moving condition. In this review, we briefly summarize the main contributions of cellular imaging techniques that have allowed relevant advances in the field of neuroendocrinology and paradigm shifts that have improved our understanding of the function of the hypothalamic-pituitary axes. The development of these methods and equipment is the result of the integration of knowledge achieved by the integration of several disciplines and effort to solve scientific questions and problems of high impact on health and society that this system entails.
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Affiliation(s)
- Edgar Jiménez-Díaz
- Laboratorio de Neuroendocrinología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Laboratorio Nacional de Soluciones Biomiméticas para Diagnóstico y Terapia LaNSBioDyT, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Diana Del-Rio
- Laboratorio de Neuroendocrinología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Laboratorio Nacional de Soluciones Biomiméticas para Diagnóstico y Terapia LaNSBioDyT, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Tatiana Fiordelisio
- Laboratorio de Neuroendocrinología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Laboratorio Nacional de Soluciones Biomiméticas para Diagnóstico y Terapia LaNSBioDyT, Universidad Nacional Autónoma de México, Mexico City, Mexico
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32
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Goenaga J, Araque A, Kofuji P, Herrera Moro Chao D. Calcium signaling in astrocytes and gliotransmitter release. Front Synaptic Neurosci 2023; 15:1138577. [PMID: 36937570 PMCID: PMC10017551 DOI: 10.3389/fnsyn.2023.1138577] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/16/2023] [Indexed: 03/06/2023] Open
Abstract
Glia are as numerous in the brain as neurons and widely known to serve supportive roles such as structural scaffolding, extracellular ionic and neurotransmitter homeostasis, and metabolic support. However, over the past two decades, several lines of evidence indicate that astrocytes, which are a type of glia, play active roles in neural information processing. Astrocytes, although not electrically active, can exhibit a form of excitability by dynamic changes in intracellular calcium levels. They sense synaptic activity and release neuroactive substances, named gliotransmitters, that modulate neuronal activity and synaptic transmission in several brain areas, thus impacting animal behavior. This "dialogue" between astrocytes and neurons is embodied in the concept of the tripartite synapse that includes astrocytes as integral elements of synaptic function. Here, we review the recent work and discuss how astrocytes via calcium-mediated excitability modulate synaptic information processing at various spatial and time scales.
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33
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Brandebura AN, Paumier A, Onur TS, Allen NJ. Astrocyte contribution to dysfunction, risk and progression in neurodegenerative disorders. Nat Rev Neurosci 2023; 24:23-39. [PMID: 36316501 DOI: 10.1038/s41583-022-00641-1] [Citation(s) in RCA: 83] [Impact Index Per Article: 83.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2022] [Indexed: 11/06/2022]
Abstract
There is increasing appreciation that non-neuronal cells contribute to the initiation, progression and pathology of diverse neurodegenerative disorders. This Review focuses on the role of astrocytes in disorders including Alzheimer disease, Parkinson disease, Huntington disease and amyotrophic lateral sclerosis. The important roles astrocytes have in supporting neuronal function in the healthy brain are considered, along with studies that have demonstrated how the physiological properties of astrocytes are altered in neurodegenerative disorders and may explain their contribution to neurodegeneration. Further, the question of whether in neurodegenerative disorders with specific genetic mutations these mutations directly impact on astrocyte function, and may suggest a driving role for astrocytes in disease initiation, is discussed. A summary of how astrocyte transcriptomic and proteomic signatures are altered during the progression of neurodegenerative disorders and may relate to functional changes is provided. Given the central role of astrocytes in neurodegenerative disorders, potential strategies to target these cells for future therapeutic avenues are discussed.
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Affiliation(s)
- Ashley N Brandebura
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Adrien Paumier
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Tarik S Onur
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Nicola J Allen
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA.
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34
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Myeong J, Klyachko VA. Rapid astrocyte-dependent facilitation amplifies multi-vesicular release in hippocampal synapses. Cell Rep 2022; 41:111820. [PMID: 36516768 PMCID: PMC9805313 DOI: 10.1016/j.celrep.2022.111820] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 09/30/2022] [Accepted: 11/21/2022] [Indexed: 12/15/2022] Open
Abstract
Synaptic facilitation is a major form of short-term plasticity typically driven by an increase in residual presynaptic calcium. Using near-total internal reflection fluorescence (near-TIRF) imaging of single vesicle release in cultured hippocampal synapses, we demonstrate a distinctive, release-dependent form of facilitation in which probability of vesicle release is higher following a successful glutamate release event than following a failure. This phenomenon has an onset of ≤500 ms and lasts several seconds, resulting in clusters of successful release events. The release-dependent facilitation requires neuronal contact with astrocytes and astrocytic glutamate uptake by EAAT1. It is not observed in neurons grown alone or in the presence of astrocyte-conditioned media. This form of facilitation dynamically amplifies multi-vesicular release. Facilitation-evoked release events exhibit spatial clustering and have a preferential localization toward the active zone center. These results uncover a rapid astrocyte-dependent form of facilitation acting via modulation of multi-vesicular release and displaying distinctive spatiotemporal properties.
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Affiliation(s)
- Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63132, USA
| | - Vitaly A. Klyachko
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63132, USA,Lead contact,Correspondence:
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35
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Denizot A, Arizono M, Nägerl UV, Berry H, De Schutter E. Control of Ca 2+ signals by astrocyte nanoscale morphology at tripartite synapses. Glia 2022; 70:2378-2391. [PMID: 36097958 PMCID: PMC9825906 DOI: 10.1002/glia.24258] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/20/2022] [Accepted: 07/28/2022] [Indexed: 01/11/2023]
Abstract
Much of the Ca2+ activity in astrocytes is spatially restricted to microdomains and occurs in fine processes that form a complex anatomical meshwork, the so-called spongiform domain. A growing body of literature indicates that those astrocytic Ca2+ signals can influence the activity of neuronal synapses and thus tune the flow of information through neuronal circuits. Because of technical difficulties in accessing the small spatial scale involved, the role of astrocyte morphology on Ca2+ microdomain activity remains poorly understood. Here, we use computational tools and idealized 3D geometries of fine processes based on recent super-resolution microscopy data to investigate the mechanistic link between astrocytic nanoscale morphology and local Ca2+ activity. Simulations demonstrate that the nano-morphology of astrocytic processes powerfully shapes the spatio-temporal properties of Ca2+ signals and promotes local Ca2+ activity. The model predicts that this effect is attenuated upon astrocytic swelling, hallmark of brain diseases, which we confirm experimentally in hypo-osmotic conditions. Upon repeated neurotransmitter release events, the model predicts that swelling hinders astrocytic signal propagation. Overall, this study highlights the influence of the complex morphology of astrocytes at the nanoscale and its remodeling in pathological conditions on neuron-astrocyte communication at so-called tripartite synapses, where astrocytic processes come into close contact with pre- and postsynaptic structures.
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Affiliation(s)
- Audrey Denizot
- Computational Neuroscience UnitOkinawa Institute of Science and TechnologyOnna‐SonJapan
| | - Misa Arizono
- Interdisciplinary Institute for NeuroscienceUniversité de BordeauxBordeauxFrance,Interdisciplinary Institute for NeuroscienceCNRS UMR 5297BordeauxFrance,Department of PharmacologyKyoto University Graduate School of MedicineKyotoJapan
| | - U. Valentin Nägerl
- Interdisciplinary Institute for NeuroscienceUniversité de BordeauxBordeauxFrance,Interdisciplinary Institute for NeuroscienceCNRS UMR 5297BordeauxFrance
| | - Hugues Berry
- LIRIS, UMR5205 CNRSUniv LyonVilleurbanneFrance,INRIAVilleurbanneFrance
| | - Erik De Schutter
- Computational Neuroscience UnitOkinawa Institute of Science and TechnologyOnna‐SonJapan
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36
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Ding F, Liang S, Li R, Yang Z, He Y, Yang S, Duan Q, Zhang J, Lyu J, Zhou Z, Huang M, Wang H, Li J, Yang C, Wang Y, Gong M, Chen S, Jia H, Chen X, Liao X, Fu L, Zhang K. Astrocytes exhibit diverse Ca2+ changes at subcellular domains during brain aging. Front Aging Neurosci 2022; 14:1029533. [PMID: 36389078 PMCID: PMC9650392 DOI: 10.3389/fnagi.2022.1029533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 10/11/2022] [Indexed: 11/23/2022] Open
Abstract
Astrocytic Ca2+ transients are essential for astrocyte integration into neural circuits. These Ca2+ transients are primarily sequestered in subcellular domains, including primary branches, branchlets and leaflets, and endfeet. In previous studies, it suggests that aging causes functional defects in astrocytes. Until now, it was unclear whether and how aging affects astrocytic Ca2+ transients at subcellular domains. In this study, we combined a genetically encoded Ca2+ sensor (GCaMP6f) and in vivo two-photon Ca2+ imaging to determine changes in Ca2+ transients within astrocytic subcellular domains during brain aging. We showed that aging increased Ca2+ transients in astrocytic primary branches, higher-order branchlets, and terminal leaflets. However, Ca2+ transients decreased within astrocytic endfeet during brain aging, which could be caused by the decreased expressions of Aquaporin-4 (AQP4). In addition, aging-induced changes of Ca2+ transient types were heterogeneous within astrocytic subcellular domains. These results demonstrate that the astrocytic Ca2+ transients within subcellular domains are affected by aging differently. This finding contributes to a better understanding of the physiological role of astrocytes in aging-induced neural circuit degeneration.
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Affiliation(s)
- Fusheng Ding
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Shanshan Liang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Ruijie Li
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
- Advanced Institute for Brain and Intelligence and School of Physical Science and Technology, Guangxi University, Nanning, China
| | - Zhiqi Yang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Yong He
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Shaofan Yang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Qingtian Duan
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Jianxiong Zhang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Jing Lyu
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Zhenqiao Zhou
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Mingzhu Huang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Haoyu Wang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Jin Li
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Chuanyan Yang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Yuxia Wang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Mingyue Gong
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
| | - Shangbin Chen
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
| | - Hongbo Jia
- Advanced Institute for Brain and Intelligence and School of Physical Science and Technology, Guangxi University, Nanning, China
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
- Combinatorial NeuroImaging Core Facility, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Xiaowei Chen
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
- Guangyang Bay Laboratory, Chongqing Institute for Brain and Intelligence, Chongqing, China
| | - Xiang Liao
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, China
- *Correspondence: Xiang Liao,
| | - Ling Fu
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
- MoE Key Laboratory for Biomedical Photonics, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, China
- Ling Fu,
| | - Kuan Zhang
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing, China
- Kuan Zhang,
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Lang R, Li H, Luo X, Liu C, Zhang Y, Guo S, Xu J, Bao C, Dong W, Yu Y. Expression and mechanisms of interferon-stimulated genes in viral infection of the central nervous system (CNS) and neurological diseases. Front Immunol 2022; 13:1008072. [PMID: 36325336 PMCID: PMC9618809 DOI: 10.3389/fimmu.2022.1008072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/28/2022] [Indexed: 09/16/2023] Open
Abstract
Interferons (IFNs) bind to cell surface receptors and activate the expression of interferon-stimulated genes (ISGs) through intracellular signaling cascades. ISGs and their expression products have various biological functions, such as antiviral and immunomodulatory effects, and are essential effector molecules for IFN function. ISGs limit the invasion and replication of the virus in a cell-specific and region-specific manner in the central nervous system (CNS). In addition to participating in natural immunity against viral infections, studies have shown that ISGs are essential in the pathogenesis of CNS disorders such as neuroinflammation and neurodegenerative diseases. The aim of this review is to present a macroscopic overview of the characteristics of ISGs that restrict viral neural invasion and the expression of the ISGs underlying viral infection of CNS cells. Furthermore, we elucidate the characteristics of ISGs expression in neurological inflammation, neuropsychiatric disorders such as depression as well as neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). Finally, we summarize several ISGs (ISG15, IFIT2, IFITM3) that have been studied more in recent years for their antiviral infection in the CNS and their research progress in neurological diseases.
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Affiliation(s)
- Rui Lang
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases), Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Huiting Li
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases), Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Xiaoqin Luo
- Department of Human Anatomy and Histoembryology, School of Basic Medical Sciences, Southwest Medical University, Luzhou, China
| | - Cencen Liu
- Department of Pathology, People’s Hospital of Zhongjiang County, DeYang, China
| | - Yiwen Zhang
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - ShunYu Guo
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Jingyi Xu
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases), Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Changshun Bao
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- Sichuan Clinical Research Center for Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- Academician (Expert) Workstation of Sichuan Province, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- Neurological diseases and brain function laboratory, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Wei Dong
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases), Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Yang Yu
- Key Laboratory of Medical Electrophysiology, Ministry of Education & Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases), Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Human Anatomy and Histoembryology, School of Basic Medical Sciences, Southwest Medical University, Luzhou, China
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38
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Abstract
The diploë region of skull has recently been discovered to act as a myeloid cell reservoir to the underlying meninges. The presence of ossified vascular channels traversing the inner skull of cortex provides a passageway for the cells to traffic from the niche, and CNS-derived antigens traveling through cerebrospinal fluid in a perivascular manner reaches the niche to signal myeloid cell egress. This review will highlight the recent findings establishing this burgeoning field along with the known role this niche plays in CNS aging and disease. It will further highlight the anatomical routes and physiological properties of the vascular structures these cells use for trafficking, spanning from skull to brain parenchyma.
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Affiliation(s)
- William A. Mills
- Brain, Immunology, and Glia CenterUniversity of VirginiaCharlottesvilleVirginiaUSA,Department of NeuroscienceUniversity of VirginiaCharlottesvilleVirginiaUSA,Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVirginiaUSA
| | - Morgan A Coburn
- Brain, Immunology, and Glia CenterUniversity of VirginiaCharlottesvilleVirginiaUSA,Department of NeuroscienceUniversity of VirginiaCharlottesvilleVirginiaUSA,Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVirginiaUSA
| | - Ukpong B. Eyo
- Brain, Immunology, and Glia CenterUniversity of VirginiaCharlottesvilleVirginiaUSA,Department of NeuroscienceUniversity of VirginiaCharlottesvilleVirginiaUSA,Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVirginiaUSA
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39
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Chi S, Cui Y, Wang H, Jiang J, Zhang T, Sun S, Zhou Z, Zhong Y, Xiao B. Astrocytic Piezo1-mediated mechanotransduction determines adult neurogenesis and cognitive functions. Neuron 2022:S0896-6273(22)00655-9. [PMID: 35963237 DOI: 10.1016/j.neuron.2022.07.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 05/31/2022] [Accepted: 07/12/2022] [Indexed: 12/12/2022]
Abstract
Adult brain activities are generally believed to be dominated by chemical and electrical transduction mechanisms. However, the importance of mechanotransduction mediated by mechano-gated ion channels in brain functions is less appreciated. Here, we show that the mechano-gated Piezo1 channel is expressed in the exploratory processes of astrocytes and utilizes its mechanosensitivity to mediate mechanically evoked Ca2+ responses and ATP release, establishing Piezo1-mediated mechano-chemo transduction in astrocytes. Piezo1 deletion in astrocytes causes a striking reduction of hippocampal volume and brain weight and severely impaired (but ATP-rescuable) adult neurogenesis in vivo, and it abolishes ATP-dependent potentiation of neural stem cell (NSC) proliferation in vitro. Piezo1-deficient mice show impaired hippocampal long-term potentiation (LTP) and learning and memory behaviors. By contrast, overexpression of Piezo1 in astrocytes sufficiently enhances mechanotransduction, LTP, and learning and memory performance. Thus, astrocytes utilize Piezo1-mediated mechanotransduction mechanisms to robustly regulate adult neurogenesis and cognitive functions, conceptually highlighting the importance of mechanotransduction in brain structure and function.
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40
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Venkataramani V, Yang Y, Schubert MC, Reyhan E, Tetzlaff SK, Wißmann N, Botz M, Soyka SJ, Beretta CA, Pramatarov RL, Fankhauser L, Garofano L, Freudenberg A, Wagner J, Tanev DI, Ratliff M, Xie R, Kessler T, Hoffmann DC, Hai L, Dörflinger Y, Hoppe S, Yabo YA, Golebiewska A, Niclou SP, Sahm F, Lasorella A, Slowik M, Döring L, Iavarone A, Wick W, Kuner T, Winkler F. Glioblastoma hijacks neuronal mechanisms for brain invasion. Cell 2022; 185:2899-2917.e31. [PMID: 35914528 DOI: 10.1016/j.cell.2022.06.054] [Citation(s) in RCA: 142] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 04/10/2022] [Accepted: 06/28/2022] [Indexed: 12/29/2022]
Abstract
Glioblastomas are incurable tumors infiltrating the brain. A subpopulation of glioblastoma cells forms a functional and therapy-resistant tumor cell network interconnected by tumor microtubes (TMs). Other subpopulations appear unconnected, and their biological role remains unclear. Here, we demonstrate that whole-brain colonization is fueled by glioblastoma cells that lack connections with other tumor cells and astrocytes yet receive synaptic input from neurons. This subpopulation corresponds to neuronal and neural-progenitor-like tumor cell states, as defined by single-cell transcriptomics, both in mouse models and in the human disease. Tumor cell invasion resembled neuronal migration mechanisms and adopted a Lévy-like movement pattern of probing the environment. Neuronal activity induced complex calcium signals in glioblastoma cells followed by the de novo formation of TMs and increased invasion speed. Collectively, superimposing molecular and functional single-cell data revealed that neuronal mechanisms govern glioblastoma cell invasion on multiple levels. This explains how glioblastoma's dissemination and cellular heterogeneity are closely interlinked.
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Affiliation(s)
- Varun Venkataramani
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
| | - Yvonne Yang
- Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Marc Cicero Schubert
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Ekin Reyhan
- Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Svenja Kristin Tetzlaff
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Niklas Wißmann
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Michael Botz
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Stella Judith Soyka
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Carlo Antonio Beretta
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Rangel Lyubomirov Pramatarov
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Laura Fankhauser
- Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Luciano Garofano
- Institute for Cancer Genetics, Columbia University Medical Center, New York, NY 10027, USA
| | | | - Julia Wagner
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Dimitar Ivanov Tanev
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Miriam Ratliff
- Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; Neurosurgery Clinic, University Hospital Mannheim, 68167 Mannheim, Germany
| | - Ruifan Xie
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Tobias Kessler
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Dirk C Hoffmann
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Ling Hai
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Yvette Dörflinger
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Simone Hoppe
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Yahaya A Yabo
- NORLUX Neuro-Oncology Laboratory, Department of Cancer Research, Luxembourg Institute of Health, 1526 Luxembourg, Luxembourg
| | - Anna Golebiewska
- NORLUX Neuro-Oncology Laboratory, Department of Cancer Research, Luxembourg Institute of Health, 1526 Luxembourg, Luxembourg
| | - Simone P Niclou
- NORLUX Neuro-Oncology Laboratory, Department of Cancer Research, Luxembourg Institute of Health, 1526 Luxembourg, Luxembourg
| | - Felix Sahm
- Department of Neuropathology, Institute of Pathology, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neuropathology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Anna Lasorella
- Institute for Cancer Genetics, Columbia University Medical Center, New York, NY 10027, USA
| | - Martin Slowik
- Institute of Mathematics, University of Mannheim, 68131 Mannheim, Germany
| | - Leif Döring
- Institute of Mathematics, University of Mannheim, 68131 Mannheim, Germany
| | - Antonio Iavarone
- Institute for Cancer Genetics, Columbia University Medical Center, New York, NY 10027, USA
| | - Wolfgang Wick
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Thomas Kuner
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany.
| | - Frank Winkler
- Neurology Clinic and National Center for Tumor Diseases, University Hospital Heidelberg, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
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Aleksandrova MA, Sukhinich KK. Astrocytes of the Brain: Retinue Plays the King. Russ J Dev Biol 2022. [DOI: 10.1134/s1062360422040026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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42
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Blum Moyse L, Berry H. Modelling the modulation of cortical Up-Down state switching by astrocytes. PLoS Comput Biol 2022; 18:e1010296. [PMID: 35862433 PMCID: PMC9345492 DOI: 10.1371/journal.pcbi.1010296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 08/02/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022] Open
Abstract
Up-Down synchronization in neuronal networks refers to spontaneous switches between periods of high collective firing activity (Up state) and periods of silence (Down state). Recent experimental reports have shown that astrocytes can control the emergence of such Up-Down regimes in neural networks, although the molecular or cellular mechanisms that are involved are still uncertain. Here we propose neural network models made of three populations of cells: excitatory neurons, inhibitory neurons and astrocytes, interconnected by synaptic and gliotransmission events, to explore how astrocytes can control this phenomenon. The presence of astrocytes in the models is indeed observed to promote the emergence of Up-Down regimes with realistic characteristics. Our models show that the difference of signalling timescales between astrocytes and neurons (seconds versus milliseconds) can induce a regime where the frequency of gliotransmission events released by the astrocytes does not synchronize with the Up and Down phases of the neurons, but remains essentially stable. However, these gliotransmission events are found to change the localization of the bifurcations in the parameter space so that with the addition of astrocytes, the network enters a bistability region of the dynamics that corresponds to Up-Down synchronization. Taken together, our work provides a theoretical framework to test scenarios and hypotheses on the modulation of Up-Down dynamics by gliotransmission from astrocytes. Neural networks in many brain regions can display synchronized activities. During the so-called “Up-Down” synchronization regimes for instance, the whole local population of neurons switches in a spontaneous and synchronized fashion between phases of high activity (Up states) and phases of low activity (Down states). The mechanisms responsible for this behaviour are still not well understood, but recent experimental reports have suggested that another type of brain cells, the astrocytes, at least partly control these oscillations. Astrocytes are increasingly believed to play a role in the propagation of signals between neurons, via their connections to neuronal synapses, but how this mechanism could control Up-Down regimes is not understood. To address this issue we present here simple mathematical models of neuronal networks that incorporate astrocytes in addition to neurons according to various levels of description. Using bifurcation analysis and numerical simulations we explore how astrocytes control Up-Down synchronization of the neuronal networks. In particular, astrocytes in the model are found to change the localization of the bifurcation points in the parameter space, so that the neurons enter the region of Up-Down regime when astrocytes are present. We also give some theoretical predictions that can be tested experimentally to test the validity of our models.
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Affiliation(s)
- Lisa Blum Moyse
- Inria, Villeurbanne, France
- LIRIS UMR5205, University of Lyon, Villeurbanne, France
| | - Hugues Berry
- Inria, Villeurbanne, France
- LIRIS UMR5205, University of Lyon, Villeurbanne, France
- * E-mail:
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43
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Åbjørsbråten KS, Skaaraas GHE, Cunen C, Bjørnstad DM, Binder KM, Bojarskaite L, Jensen V, Nilsson LNG, Rao SB, Tang W, Hermansen GH, Nagelhus EA, Ottersen OP, Torp R, Enger R. Impaired astrocytic Ca 2+ signaling in awake-behaving Alzheimer's disease transgenic mice. eLife 2022; 11:75055. [PMID: 35833623 PMCID: PMC9352348 DOI: 10.7554/elife.75055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 06/29/2022] [Indexed: 11/22/2022] Open
Abstract
Increased astrocytic Ca2+ signaling has been shown in Alzheimer’s disease mouse models, but to date no reports have characterized behaviorally induced astrocytic Ca2+ signaling in such mice. Here, we employ an event-based algorithm to assess astrocytic Ca2+ signals in the neocortex of awake-behaving tg-ArcSwe mice and non-transgenic wildtype littermates while monitoring pupil responses and behavior. We demonstrate an attenuated astrocytic Ca2+ response to locomotion and an uncoupling of pupil responses and astrocytic Ca2+ signaling in 15-month-old plaque-bearing mice. Using the genetically encoded fluorescent norepinephrine sensor GRABNE, we demonstrate a reduced norepinephrine signaling during spontaneous running and startle responses in the transgenic mice, providing a possible mechanistic underpinning of the observed reduced astrocytic Ca2+ responses. Our data points to a dysfunction in the norepinephrine–astrocyte Ca2+ activity axis, which may account for some of the cognitive deficits observed in Alzheimer’s disease. Neurodegenerative conditions such as Parkinson’s or Alzheimer’s disease are characterized by neurons dying and being damaged. Yet neurons are only one type of brain actors; astrocytes, for example, are star-shaped ‘companion’ cells that have recently emerged as being able to fine-tune neuronal communication. In particular, they can respond to norepinephrine, a signaling molecule that acts to prepare the brain and body for action. This activation results, for instance, in astrocytes releasing chemicals that can act on neurons. Certain cognitive symptoms associated with Alzheimer’s disease could be due to a lack of norepinephrine. In parallel, studies in anaesthetized mice have shown perturbed astrocyte signaling in a model of the condition. Disrupted norepinephrine-triggered astrocyte signaling could therefore be implicated in the symptoms of the disease. Experiments in awake mice are needed to investigate this link, especially as anesthesia is known to disrupt the activity of astrocytes. To explore this question, Åbjørsbråten, Skaaraas et al. conducted experiments in naturally behaving mice expressing mutations found in patients with early-onset Alzheimer’s disease. These mice develop hallmarks of the disorder. Compared to their healthy counterparts, these animals had reduced astrocyte signaling when running or being startled. Similarly, a fluorescent molecular marker for norepinephrine demonstrated less signaling in the modified mice compared to healthy ones. Over 55 million individuals currently live with Alzheimer’s disease. The results by Åbjørsbråten, Skaaraas et al. suggest that astrocyte–norepinephrine communication may be implicated in the condition, an avenue of research that could potentially lead to developing new treatments.
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Affiliation(s)
| | - Gry H E Skaaraas
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Céline Cunen
- Department of Mathematics, University of Oslo, Oslo, Norway
| | | | - Kristin M Binder
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | | | - Vidar Jensen
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | | | - Shreyas B Rao
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Wannan Tang
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | | | | | | | - Reidun Torp
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Rune Enger
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
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Yin R, Noble BC, He F, Zolotavin P, Rathore H, Jin Y, Sevilla N, Xie C, Luan L. Chronic co-implantation of ultraflexible neural electrodes and a cranial window. Neurophotonics 2022; 9:032204. [PMID: 35036472 PMCID: PMC8756486 DOI: 10.1117/1.nph.9.3.032204] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/04/2021] [Indexed: 06/01/2023]
Abstract
Significance: Electrophysiological recording and optical imaging are two prevalent neurotechnologies with complementary strengths, the combined application of which can significantly improve our capacity in deciphering neural circuits. Flexible electrode arrays can support longitudinal optical imaging in the same brain region, but their mechanical flexibility makes surgical preparation challenging. Here, we provide a step-by-step protocol by which an ultraflexible nanoelectronic thread is co-implanted with a cranial window in a single surgery to enable chronic, dual-modal measurements. Aim: The method uses 1 - μ m -thick polymer neural electrodes which conform to the site of implantation. The mechanical flexibility of the probe allows bending without breaking and enables long-lasting electrophysiological recordings of single-unit activities and concurrent, high-resolution optical imaging through the cranial window. Approach: The protocol describes methods and procedures to co-implant an ultraflexible electrode array and a glass cranial window in the mouse neocortex. The implantation strategy includes temporary attachment of flexible electrodes to a retractable tungsten-microwire insertion shuttle, craniotomy, stereotaxic insertion of the electrode array, skull fixation of the cranial window and electrode, and installation of a head plate. Results: The resultant implant allows simultaneous interrogation of brain activity both electrophysiologically and optically for several months. Importantly, a variety of optical imaging modalities, including wide-field fluorescent imaging, two-photon microscopy, and functional optical imaging, can be readily applied to the specific brain region where ultraflexible electrodes record from. Conclusions: The protocol describes a method for co-implantation of ultraflexible neural electrodes and a cranial window for chronic, multimodal measurements of brain activity in mice. Device preparation and surgical implantation are described in detail to guide the adaptation of these methods for other flexible neural implants and cranial windows.
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Affiliation(s)
- Rongkang Yin
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
| | - Brian C. Noble
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
- Rice University, Applied Physics Graduate Program, Houston, Texas, United States
| | - Fei He
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
| | - Pavlo Zolotavin
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
| | - Haad Rathore
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
- Rice University, Applied Physics Graduate Program, Houston, Texas, United States
| | - Yifu Jin
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
| | - Nicole Sevilla
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
- Rice University, Department of Bioengineering, Houston, Texas, United States
| | - Chong Xie
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
- Rice University, Department of Bioengineering, Houston, Texas, United States
| | - Lan Luan
- Rice University, Department of Electrical and Computer Engineering, Houston, Texas, United States
- Rice University, Rice Neuroengineering Initiative, Houston, Texas, United States
- Rice University, Department of Bioengineering, Houston, Texas, United States
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45
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Beloate LN, Zhang N. Connecting the dots between cell populations, whole-brain activity, and behavior. Neurophotonics 2022; 9:032208. [PMID: 35350137 PMCID: PMC8957372 DOI: 10.1117/1.nph.9.3.032208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
Simultaneously manipulating and monitoring both microscopic and macroscopic brain activity in vivo and identifying the linkage to behavior are powerful tools in neuroscience research. These capabilities have been realized with the recent technical advances of optogenetics and its combination with fMRI, here termed "opto-fMRI." Opto-fMRI allows for targeted brain region-, cell-type-, or projection-specific manipulation and targeted Ca 2 + activity measurement to be linked with global brain signaling and behavior. We cover the history, technical advances, applications, and important considerations of opto-fMRI in anesthetized and awake rodents and the future directions of the combined techniques in neuroscience and neuroimaging.
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Affiliation(s)
- Lauren N. Beloate
- Pennsylvania State University, Department of Biomedical Engineering, Pennsylvania, United States
| | - Nanyin Zhang
- Pennsylvania State University, Department of Biomedical Engineering, Pennsylvania, United States
- Pennsylvania State University, Huck Institutes of the Life Sciences, Pennsylvania, United States
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46
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Covelo A, Badoual A, Denizot A. Reinforcing Interdisciplinary Collaborations to Unravel the Astrocyte "Calcium Code". J Mol Neurosci 2022. [PMID: 35543801 DOI: 10.1007/s12031-022-02006-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 04/01/2022] [Indexed: 11/19/2022]
Abstract
In this review article, we present the major insights from and challenges faced in the acquisition, analysis and modeling of astrocyte calcium activity, aiming at bridging the gap between those fields to crack the complex astrocyte “Calcium Code”. We then propose strategies to reinforce interdisciplinary collaborative projects to unravel astrocyte function in health and disease.
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Dou WT, Han HH, Sedgwick AC, Zhu GB, Zang Y, Yang XR, Yoon J, James TD, Li J, He XP. Fluorescent probes for the detection of disease-associated biomarkers. Sci Bull (Beijing) 2022; 67:853-878. [PMID: 36546238 DOI: 10.1016/j.scib.2022.01.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/30/2021] [Accepted: 01/04/2022] [Indexed: 01/10/2023]
Abstract
Fluorescent probes have emerged as indispensable chemical tools to the field of chemical biology and medicine. The ability to detect intracellular species and monitor physiological processes has not only advanced our knowledge in biology but has provided new approaches towards disease diagnosis. In this review, we detail the design criteria and strategies for some recently reported fluorescent probes that can detect a wide range of biologically important species in cells and in vivo. In doing so, we highlight the importance of each biological species and their role in biological systems and for disease progression. We then discuss the current problems and challenges of existing technologies and provide our perspective on the future directions of the research area. Overall, we hope this review will provide inspiration for researchers and prove as useful guide for the development of the next generation of fluorescent probes.
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Affiliation(s)
- Wei-Tao Dou
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Hai-Hao Han
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Adam C Sedgwick
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712-1224, USA
| | - Guo-Biao Zhu
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yi Zang
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xin-Rong Yang
- Department of Liver Surgery & Transplantation, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai 200032, China.
| | - Juyoung Yoon
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea.
| | - Tony D James
- Department of Chemistry, University of Bath, Bath BA2 7AY, UK; School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China.
| | - Jia Li
- National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
| | - Xiao-Peng He
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
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Pankratova EV, Sinitsina MS, Gordleeva S, Kazantsev VB. Bistability and Chaos Emergence in Spontaneous Dynamics of Astrocytic Calcium Concentration. Mathematics 2022; 10:1337. [DOI: 10.3390/math10081337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this work, we consider a mathematical model describing spontaneous calcium signaling in astrocytes. Based on biologically relevant principles, this model simulates experimentally observed calcium oscillations and can predict the emergence of complicated dynamics. Using analytical and numerical analysis, various attracting sets were found and investigated. Employing bifurcation theory analysis, we examined steady state solutions, bistability, simple and complicated periodic limit cycles and also chaotic attractors. We found that astrocytes possess a variety of complex dynamical modes, including chaos and multistability, that can further provide different modulations of neuronal circuits, enhancing their plasticity and flexibility.
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Tran CHT. Toolbox for studying neurovascular coupling in vivo, with a focus on vascular activity and calcium dynamics in astrocytes. Neurophotonics 2022; 9:021909. [PMID: 35295714 PMCID: PMC8920490 DOI: 10.1117/1.nph.9.2.021909] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 02/23/2022] [Indexed: 05/14/2023]
Abstract
Significance: Insights into the cellular activity of each member of the neurovascular unit (NVU) is critical for understanding their contributions to neurovascular coupling (NVC)-one of the key control mechanisms in cerebral blood flow regulation. Advances in imaging and genetic tools have enhanced our ability to observe, manipulate and understand the cellular activity of NVU components, namely neurons, astrocytes, microglia, endothelial cells, vascular smooth muscle cells, and pericytes. However, there are still many unresolved questions. Since astrocytes are considered electrically unexcitable, Ca 2 + signaling is the main parameter used to monitor their activity. It is therefore imperative to study astrocytic Ca 2 + dynamics simultaneously with vascular activity using tools appropriate for the question of interest. Aim: To highlight currently available genetic and imaging tools for studying the NVU-and thus NVC-with a focus on astrocyte Ca 2 + dynamics and vascular activity, and discuss the utility, technical advantages, and limitations of these tools for elucidating NVC mechanisms. Approach: We draw attention to some outstanding questions regarding the mechanistic basis of NVC and emphasize the role of astrocytic Ca 2 + elevations in functional hyperemia. We further discuss commonly used genetic, and optical imaging tools, as well as some newly developed imaging modalities for studying NVC at the cellular level, highlighting their advantages and limitations. Results: We provide an overview of the current state of NVC research, focusing on the role of astrocytic Ca 2 + elevations in functional hyperemia; summarize recent advances in genetically engineered Ca 2 + indicators, fluorescence microscopy techniques for studying NVC; and discuss the unmet challenges for future imaging development. Conclusions: Advances in imaging techniques together with improvements in genetic tools have significantly contributed to our understanding of NVC. Many pieces of the puzzle have been revealed, but many more remain to be discovered. Ultimately, optimizing NVC research will require a concerted effort to improve imaging techniques, available genetic tools, and analytical software.
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Affiliation(s)
- Cam Ha T. Tran
- University of Nevada, Reno School of Medicine, Department of Physiology and Cell Biology, Reno, Nevada, United States
- Address all correspondence to Cam Ha T. Tran,
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Gorzo KA, Gordon GR. Photonics tools begin to clarify astrocyte calcium transients. Neurophotonics 2022; 9:021907. [PMID: 35211642 PMCID: PMC8857908 DOI: 10.1117/1.nph.9.2.021907] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/01/2022] [Indexed: 05/27/2023]
Abstract
Astrocytes integrate information from neurons and the microvasculature to coordinate brain activity and metabolism. Using a variety of calcium-dependent cellular mechanisms, these cells impact numerous aspects of neurophysiology in health and disease. Astrocyte calcium signaling is highly diverse, with complex spatiotemporal features. Here, we review astrocyte calcium dynamics and the optical imaging tools used to measure and analyze these events. We briefly cover historical calcium measurements, followed by our current understanding of how calcium transients relate to the structure of astrocytes. We then explore newer photonics tools including super-resolution techniques and genetically encoded calcium indicators targeted to specific cellular compartments and how these have been applied to astrocyte biology. Finally, we provide a brief overview of analysis software used to accurately quantify the data and ultimately aid in our interpretation of the various functions of astrocyte calcium transients.
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Affiliation(s)
- Kelsea A. Gorzo
- University of Calgary, Hotchkiss Brain Institute, Cumming School of Medicine, Calgary, Alberta, Canada
| | - Grant R. Gordon
- University of Calgary, Hotchkiss Brain Institute, Cumming School of Medicine, Calgary, Alberta, Canada
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