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Li H, Qian J, Wang Y, Wang J, Mi X, Qu L, Song N, Xie J. Potential convergence of olfactory dysfunction in Parkinson's disease and COVID-19: The role of neuroinflammation. Ageing Res Rev 2024; 97:102288. [PMID: 38580172 DOI: 10.1016/j.arr.2024.102288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/28/2024] [Accepted: 03/30/2024] [Indexed: 04/07/2024]
Abstract
Parkinson's disease (PD) is a prevalent neurodegenerative disorder that affects 7-10 million individuals worldwide. A common early symptom of PD is olfactory dysfunction (OD), and more than 90% of PD patients suffer from OD. Recent studies have highlighted a high incidence of OD in patients with SARS-CoV-2 infection. This review investigates the potential convergence of OD in PD and COVID-19, particularly focusing on the mechanisms by which neuroinflammation contributes to OD and neurological events. Starting from our fundamental understanding of the olfactory bulb, we summarize the clinical features of OD and pathological features of the olfactory bulb from clinical cases and autopsy reports in PD patients. We then examine SARS-CoV-2-induced olfactory bulb neuropathology and OD and emphasize the SARS-CoV-2-induced neuroinflammatory cascades potentially leading to PD manifestations. By activating microglia and astrocytes, as well as facilitating the aggregation of α-synuclein, SARS-CoV-2 could contribute to the onset or exacerbation of PD. We also discuss the possible contributions of NF-κB, the NLRP3 inflammasome, and the JAK/STAT, p38 MAPK, TLR4, IL-6/JAK2/STAT3 and cGAS-STING signaling pathways. Although olfactory dysfunction in patients with COVID-19 may be reversible, it is challenging to restore OD in patients with PD. With the emergence of new SARS-CoV-2 variants and the recurrence of infections, we call for continued attention to the intersection between PD and SARS-CoV-2 infection, especially from the perspective of OD.
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Affiliation(s)
- Hui Li
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Junliang Qian
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Youcui Wang
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Juan Wang
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Xiaoqing Mi
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Le Qu
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Ning Song
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China.
| | - Junxia Xie
- Institute of Brain Science and Disease, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China.
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2
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Dossi E, Zonca L, Pivonkova H, Milior G, Moulard J, Vargova L, Chever O, Holcman D, Rouach N. Astroglial gap junctions strengthen hippocampal network activity by sustaining afterhyperpolarization via KCNQ channels. Cell Rep 2024; 43:114158. [PMID: 38722742 DOI: 10.1016/j.celrep.2024.114158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/01/2024] [Accepted: 04/11/2024] [Indexed: 06/01/2024] Open
Abstract
Throughout the brain, astrocytes form networks mediated by gap junction channels that promote the activity of neuronal ensembles. Although their inputs on neuronal information processing are well established, how molecular gap junction channels shape neuronal network patterns remains unclear. Here, using astroglial connexin-deficient mice, in which astrocytes are disconnected and neuronal bursting patterns are abnormal, we show that astrocyte networks strengthen bursting activity via dynamic regulation of extracellular potassium levels, independently of glutamate homeostasis or metabolic support. Using a facilitation-depression model, we identify neuronal afterhyperpolarization as the key parameter underlying bursting pattern regulation by extracellular potassium in mice with disconnected astrocytes. We confirm this prediction experimentally and reveal that astroglial network control of extracellular potassium sustains neuronal afterhyperpolarization via KCNQ voltage-gated K+ channels. Altogether, these data delineate how astroglial gap junctions mechanistically strengthen neuronal population bursts and point to approaches for controlling aberrant activity in neurological diseases.
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Affiliation(s)
- Elena Dossi
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Lou Zonca
- Group of Data Modeling and Computational Biology, Institute of Biology, Ecole Normale Superieure, CNRS, INSERM, Université PSL, Paris, France; ED386, Ecole Doctorale de Sciences Mathématiques Paris Centre, Paris, France
| | - Helena Pivonkova
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France; Department of Cellular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czech Republic; 2(nd) Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Giampaolo Milior
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Julien Moulard
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - Lydia Vargova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine, Czech Academy of Sciences, Prague, Czech Republic; 2(nd) Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Oana Chever
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France
| | - David Holcman
- Group of Data Modeling and Computational Biology, Institute of Biology, Ecole Normale Superieure, CNRS, INSERM, Université PSL, Paris, France.
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, Université PSL, Paris, France.
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3
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Herwerth M, Wyss MT, Schmid NB, Condrau J, Ravotto L, Mateos Melero JM, Kaech A, Bredell G, Thomas C, Stadelmann C, Misgeld T, Bennett JL, Saab AS, Jessberger S, Weber B. Astrocytes adopt a progenitor-like migratory strategy for regeneration in adult brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.18.594292. [PMID: 38798654 PMCID: PMC11118580 DOI: 10.1101/2024.05.18.594292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Mature astrocytes become activated upon non-specific tissue damage and contribute to glial scar formation. Proliferation and migration of adult reactive astrocytes after injury is considered very limited. However, the regenerative behavior of individual astrocytes following selective astroglial loss, as seen in astrocytopathies, such as neuromyelitis optica spectrum disorder, remains unexplored. Here, we performed longitudinal in vivo imaging of cortical astrocytes after focal astrocyte ablation in mice. We discovered that perilesional astrocytes develop a remarkable plasticity for efficient lesion repopulation. A subset of mature astrocytes transforms into reactive progenitor-like (REPL) astrocytes that not only undergo multiple asymmetric divisions but also remain in a multinucleated interstage. This regenerative response facilitates efficient migration of newly formed daughter cell nuclei towards unoccupied astrocyte territories. Our findings define the cellular principles of astrocyte plasticity upon focal lesion, unravelling the REPL phenotype as a fundamental regenerative strategy of mature astrocytes to restore astrocytic networks in the adult mammalian brain. Promoting this regenerative phenotype bears therapeutic potential for neurological conditions involving glial dysfunction.
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4
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Lalo U, Pankratov Y. Astrocyte ryanodine receptors facilitate gliotransmission and astroglial modulation of synaptic plasticity. Front Cell Neurosci 2024; 18:1382010. [PMID: 38812795 PMCID: PMC11135129 DOI: 10.3389/fncel.2024.1382010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 04/29/2024] [Indexed: 05/31/2024] Open
Abstract
Intracellular Ca2+-signaling in astrocytes is instrumental for their brain "housekeeping" role and astroglial control of synaptic plasticity. An important source for elevating the cytosolic Ca2+ level in astrocytes is a release from endoplasmic reticulum which can be triggered via two fundamental pathways: IP3 receptors and calcium-induced calcium release (CICR) mediated by Ca2+-sensitive ryanodine receptors (RyRs). While the physiological role for glial IP3 became a focus of intensive research and debate, ryanodine receptors received much less attention. We explored the role for ryanodine receptors in the modulation of cytosolic Ca2+-signaling in the cortical and hippocampal astrocytes, astrocyte-neuron communication and astroglia modulation of synaptic plasticity. Our data show that RyR-mediated Ca2+-induced Ca2+-release from ER brings substantial contribution into signaling in the functional microdomains hippocampal and neocortical astrocytes. Furthermore, RyR-mediated CICR activated the release of ATP and glutamate from hippocampal and neocortical astrocytes which, in turn, elicited transient purinergic and tonic glutamatergic currents in the neighboring pyramidal neurons. The CICR-facilitated release of ATP and glutamate was inhibited after intracellular perfusion of astrocytes with ryanodine and BAPTA and in the transgenic dnSNARE mice with impaired astroglial exocytosis. We also found out that RyR-mediated amplification of astrocytic Ca2+-signaling enhanced the long-term synaptic potentiation in the hippocampus and neocortex of aged mice. Combined, our data demonstrate that ryanodine receptors are essential for astrocytic Ca2+-signaling and efficient astrocyte-neuron communications. The RyR-mediated CICR contributes to astrocytic control of synaptic plasticity and can underlie, at least partially, neuroprotective and cognitive effects of caffein.
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Affiliation(s)
| | - Yuriy Pankratov
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
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5
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Jia C, Gill WD, Lovins C, Brown RW, Hagg T. Astrocyte focal adhesion kinase reduces passive stress coping by inhibiting ciliary neurotrophic factor only in female mice. Neurobiol Stress 2024; 30:100621. [PMID: 38516563 PMCID: PMC10955429 DOI: 10.1016/j.ynstr.2024.100621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 02/14/2024] [Accepted: 03/05/2024] [Indexed: 03/23/2024] Open
Abstract
Astrocytes have been implicated in stress responses and produce ciliary neurotrophic factor (CNTF), which we have shown in the mouse medial amygdala (MeA) to promote passive stress coping response only in females. Pharmacological inhibition of focal adhesion kinase (FAK) upregulates CNTF expression. Here, we found that inducible knockout of FAK in astrocytes or systemic treatment with an FAK inhibitor increased passive coping behavior, i.e., immobility, in an acute forced swim stress test in female, but not male, mice. Strikingly, four weeks of chronic unpredictable stress (CUS) did not further increase passive coping in female astrocytic FAK knockout mice, whereas it exacerbated it in female wildtype mice and male mice of both genotypes. These data suggest that astrocyte FAK inhibition is required for chronic stress-induced passive coping in females. Indeed, CUS reduced phospho-FAK and increased CNTF in the female MeA. Progesterone treatment after ovariectomy activated amygdala FAK and alleviated ovariectomy-induced passive coping in wildtype, but not astrocytic FAK knockout females. This suggests that progesterone-mediated activation of FAK in astrocytes reduces female stress responses. Finally, astrocytic FAK knockout or FAK inhibitor treatment increased CNTF expression in the MeA of both sexes, although not in the hippocampus. As mentioned, MeA CNTF promotes stress responses only in females, which may explain the female-specific role of astrocytic FAK inhibition. Together, this study reveals a novel female-specific progesterone-astrocytic FAK pathway that counteracts CNTF-mediated stress responses and points to opportunities for developing treatments for stress-related disorders in women.
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Affiliation(s)
- Cuihong Jia
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
| | - W. Drew Gill
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
| | - Chiharu Lovins
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
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6
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Gong L, Pasqualetti F, Papouin T, Ching S. Astrocytes as a mechanism for contextually-guided network dynamics and function. PLoS Comput Biol 2024; 20:e1012186. [PMID: 38820533 PMCID: PMC11168681 DOI: 10.1371/journal.pcbi.1012186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 06/12/2024] [Accepted: 05/21/2024] [Indexed: 06/02/2024] Open
Abstract
Astrocytes are a ubiquitous and enigmatic type of non-neuronal cell and are found in the brain of all vertebrates. While traditionally viewed as being supportive of neurons, it is increasingly recognized that astrocytes play a more direct and active role in brain function and neural computation. On account of their sensitivity to a host of physiological covariates and ability to modulate neuronal activity and connectivity on slower time scales, astrocytes may be particularly well poised to modulate the dynamics of neural circuits in functionally salient ways. In the current paper, we seek to capture these features via actionable abstractions within computational models of neuron-astrocyte interaction. Specifically, we engage how nested feedback loops of neuron-astrocyte interaction, acting over separated time-scales, may endow astrocytes with the capability to enable learning in context-dependent settings, where fluctuations in task parameters may occur much more slowly than within-task requirements. We pose a general model of neuron-synapse-astrocyte interaction and use formal analysis to characterize how astrocytic modulation may constitute a form of meta-plasticity, altering the ways in which synapses and neurons adapt as a function of time. We then embed this model in a bandit-based reinforcement learning task environment, and show how the presence of time-scale separated astrocytic modulation enables learning over multiple fluctuating contexts. Indeed, these networks learn far more reliably compared to dynamically homogeneous networks and conventional non-network-based bandit algorithms. Our results fuel the notion that neuron-astrocyte interactions in the brain benefit learning over different time-scales and the conveyance of task-relevant contextual information onto circuit dynamics.
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Affiliation(s)
- Lulu Gong
- Department of Electrical and Systems Engineering, Washington University, St. Louis, Missouri, United States of America
| | - Fabio Pasqualetti
- Department of Mechanical Engineering, University of California, Riverside, California, United States of America
| | - Thomas Papouin
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - ShiNung Ching
- Department of Electrical and Systems Engineering, Washington University, St. Louis, Missouri, United States of America
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7
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Su Y, Verkhratsky A, Yi C. Targeting connexins: possible game changer in managing neuropathic pain? Trends Mol Med 2024:S1471-4914(24)00064-9. [PMID: 38594094 DOI: 10.1016/j.molmed.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024]
Abstract
Neuropathic pain is a chronic debilitating condition caused by nerve injury or a variety of diseases. At the core of neuropathic pain lies the aberrant neuronal excitability in the peripheral and/or central nervous system (PNS and CNS). Enhanced connexin expression and abnormal activation of connexin-assembled gap junctional channels are prominent in neuropathic pain along with reactive gliosis, contributing to neuronal hypersensitivity and hyperexcitability. In this review, we delve into the current understanding of how connexin expression and function contribute to the pathogenesis and pathophysiology of neuropathic pain and argue for connexins as potential therapeutic targets for neuropathic pain management.
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Affiliation(s)
- Yixun Su
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, Bilbao, Spain; Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania; Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China.
| | - Chenju Yi
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou, China; Shenzhen Key Laboratory of Chinese Medicine Active substance screening and Translational Research, Shenzhen, China.
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8
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Chamaa F, Magistretti PJ, Fiumelli H. Astrocyte-derived lactate in stress disorders. Neurobiol Dis 2024; 192:106417. [PMID: 38296112 DOI: 10.1016/j.nbd.2024.106417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 12/04/2023] [Accepted: 01/23/2024] [Indexed: 02/05/2024] Open
Abstract
Stress disorders are psychiatric disorders arising following stressful or traumatic events. They could deleteriously affect an individual's health because they often co-occur with mental illnesses. Considerable attention has been focused on neurons when considering the neurobiology of stress disorders. However, like other mental health conditions, recent studies have highlighted the importance of astrocytes in the pathophysiology of stress-related disorders. In addition to their structural and homeostatic support role, astrocytes actively serve several functions in regulating synaptic transmission and plasticity, protecting neurons from toxic compounds, and providing metabolic support for neurons. The astrocyte-neuron lactate shuttle model sets forth the importance of astrocytes in providing lactate for the metabolic supply of neurons under intense activity. Lactate also plays a role as a signaling molecule and has been recently studied regarding its antidepressant activity. This review discusses the involvement of astrocytes and brain energy metabolism in stress and further reflects on the importance of lactate as an energy supply in the brain and its emerging antidepressant role in stress-related disorders.
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Affiliation(s)
- Farah Chamaa
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Pierre J Magistretti
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Hubert Fiumelli
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
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9
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Li J, Qi H, Chen Y, Zhu X. Epilepsy and demyelination: Towards a bidirectional relationship. Prog Neurobiol 2024; 234:102588. [PMID: 38378072 DOI: 10.1016/j.pneurobio.2024.102588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 02/13/2024] [Indexed: 02/22/2024]
Abstract
Demyelination stands out as a prominent feature in individuals with specific types of epilepsy. Concurrently, individuals with demyelinating diseases, such as multiple sclerosis (MS) are at a greater risk of developing epilepsy compared to non-MS individuals. These bidirectional connections raise the question of whether both pathological conditions share common pathogenic mechanisms. This review focuses on the reciprocal relationship between epilepsy and demyelination diseases. We commence with an overview of the neurological basis of epilepsy and demyelination diseases, followed by an exploration of how our comprehension of these two disorders has evolved in tandem. Additionally, we discuss the potential pathogenic mechanisms contributing to the interactive relationship between these two diseases. A more nuanced understanding of the interplay between epilepsy and demyelination diseases has the potential to unveiling the molecular intricacies of their pathological relationships, paving the way for innovative directions in future clinical management and treatment strategies for these diseases.
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Affiliation(s)
- Jiayi Li
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China; Clinical Medicine, Medical School of Southeast University, Nanjing, China
| | - Honggang Qi
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China
| | - Yuzhou Chen
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China; Clinical Medicine, Medical School of Southeast University, Nanjing, China
| | - Xinjian Zhu
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China.
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10
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Pelz L, Dossou L, Kompier N, Jüttner R, Siemonsmeier G, Meyer N, Lowenstein ED, Lahmann I, Kettenmann H, Birchmeier C, Rathjen FG. The IgCAM BT-IgSF (IgSF11) is essential for connexin43-mediated astrocyte-astrocyte coupling in mice. eNeuro 2024; 11:ENEURO.0283-23.2024. [PMID: 38388443 PMCID: PMC10957231 DOI: 10.1523/eneuro.0283-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 01/19/2024] [Accepted: 01/24/2024] [Indexed: 02/24/2024] Open
Abstract
The type I transmembrane protein BT-IgSF is predominantly localized in the brain and testes. It belongs to the CAR subgroup of Ig cell adhesion proteins, that are hypothesized to regulate connexin expression or localization. Here, we studied the putative link between BT-IgSF and connexins in astrocytes, ependymal cells and neurons of the mouse. Global knockout of BT-IgSF caused an increase in the clustering of connexin43 (Gja1), but not of connexin30 (Gjb6), on astrocytes and ependymal cells. Additionally, knockout animals displayed reduced expression levels of connexin43 protein in the cortex and hippocampus. Importantly, analysis of biocytin spread in hippocampal or cortical slices from mature mice of either sex revealed a decrease in astrocytic cell-cell coupling in the absence of BT-IgSF. Blocking either protein biosynthesis or proteolysis showed that the lysosomal pathway increased connexin43 degradation in astrocytes. Localization of connexin43 in subcellular compartments was not impaired in astrocytes of BT-IgSF mutants. In contrast to connexin43 the localization and expression of connexin36 (Gjd2) on neurons was not affected by the absence of BT-IgSF. Overall, our data indicate that the IgCAM BT-IgSF is essential for correct gap junction-mediated astrocyte-to-astrocyte cell communication.Significance Statement Astrocytes regulate a variety of physiological processes in the developing and adult brain that are essential for proper brain function. Astrocytes form extensive networks in the brain and communicate via gap junctions. Disruptions of gap junction coupling are found in several diseases such as neurodegeneration or epilepsy. Here, we demonstrate that the cell adhesion protein BT-IgSF is essential for gap junction mediated coupling between astrocytes in the cortex and hippocampus.
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Affiliation(s)
- Laura Pelz
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | - Laura Dossou
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | - Nine Kompier
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | - René Jüttner
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | | | - Niklas Meyer
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | | | - Ines Lahmann
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
| | - Helmut Kettenmann
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Carmen Birchmeier
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin 10117, Germany
| | - Fritz G. Rathjen
- Max-Delbrück-Center for Molecular Medicine, Berlin DE-13092, Germany
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11
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Scott EY, Safarian N, Casasbuenas DL, Dryden M, Tockovska T, Ali S, Peng J, Daniele E, Nie Xin Lim I, Bang KWA, Tripathy S, Yuzwa SA, Wheeler AR, Faiz M. Integrating single-cell and spatially resolved transcriptomic strategies to survey the astrocyte response to stroke in male mice. Nat Commun 2024; 15:1584. [PMID: 38383565 PMCID: PMC10882052 DOI: 10.1038/s41467-024-45821-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 01/31/2024] [Indexed: 02/23/2024] Open
Abstract
Astrocytes, a type of glial cell in the central nervous system (CNS), adopt diverse states in response to injury that are influenced by their location relative to the insult. Here, we describe a platform for spatially resolved, single-cell transcriptomics and proteomics, called tDISCO (tissue-digital microfluidic isolation of single cells for -Omics). We use tDISCO alongside two high-throughput platforms for spatial (Visium) and single-cell transcriptomics (10X Chromium) to examine the heterogeneity of the astrocyte response to a cortical ischemic stroke in male mice. We show that integration of Visium and 10X Chromium datasets infers two astrocyte populations, proximal or distal to the injury site, while tDISCO determines the spatial boundaries and molecular profiles that define these populations. We find that proximal astrocytes show differences in lipid shuttling, with enriched expression of Apoe and Fabp5. Our datasets provide a resource for understanding the roles of astrocytes in stroke and showcase the utility of tDISCO for hypothesis-driven, spatially resolved single-cell experiments.
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Affiliation(s)
- Erica Y Scott
- Department of Surgery, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Nickie Safarian
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario, M5T 1R8, Canada
- The Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, CA, 250 College St., Toronto, Ontario, M5T 1R8, Canada
| | - Daniela Lozano Casasbuenas
- Department of Surgery, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Michael Dryden
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Teodora Tockovska
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Shawar Ali
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Jiaxi Peng
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
| | - Emerson Daniele
- Department of Surgery, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
- Institute of Medical Sciences, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Isabel Nie Xin Lim
- Department of Surgery, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - K W Annie Bang
- Lunenfeld-Tanenbaum Research Institute, Flow Cytometry Core, Sinai Health, Toronto, Ontario, M5G 1X5, Canada
| | - Shreejoy Tripathy
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario, M5T 1R8, Canada
- The Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, CA, 250 College St., Toronto, Ontario, M5T 1R8, Canada
| | - Scott A Yuzwa
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Aaron R Wheeler
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E1, Canada
- Institute of Biomedical Engineering, University of Toronto, 164 College St., Toronto, ON, M5S 3G9, Canada
| | - Maryam Faiz
- Department of Surgery, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
- Institute of Medical Sciences, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
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12
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Fong H, Zhou B, Feng H, Luo C, Bai B, Zhang J, Wang Y. Recapitulation of Structure-Function-Regulation of Blood-Brain Barrier under (Patho)Physiological Conditions. Cells 2024; 13:260. [PMID: 38334652 PMCID: PMC10854731 DOI: 10.3390/cells13030260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/12/2024] [Accepted: 01/19/2024] [Indexed: 02/10/2024] Open
Abstract
The blood-brain barrier (BBB) is a remarkable and intricate barrier that controls the exchange of molecules between the bloodstream and the brain. Its role in maintaining the stability of the central nervous system cannot be overstated. Over the years, advancements in neuroscience and technology have enabled us to delve into the cellular and molecular components of the BBB, as well as its regulation. Yet, there is a scarcity of comprehensive reviews that follow a logical framework of structure-function-regulation, particularly focusing on the nuances of BBB regulation under both normal and pathological conditions. This review sets out to address this gap by taking a historical perspective on the discovery of the BBB and highlighting the major observations that led to its recognition as a distinct brain barrier. It explores the intricate cellular elements contributing to the formation of the BBB, including endothelial cells, pericytes, astrocytes, and neurons, emphasizing their collective role in upholding the integrity and functionality of the BBB. Furthermore, the review delves into the dynamic regulation of the BBB in physiological states, encompassing neural, humoral, and auto-regulatory mechanisms. By shedding light on these regulatory processes, a deeper understanding of the BBB's response to various physiological cues emerges. This review also investigates the disruption of the BBB integrity under diverse pathological conditions, such as ischemia, infection, and toxin exposure. It elucidates the underlying mechanisms that contribute to BBB dysfunction and explores potential therapeutic strategies that aim to restore the BBB integrity and function. Overall, this recapitulation provides valuable insights into the structure, functions, and regulation of the BBB. By integrating historical perspectives, cellular elements, regulatory mechanisms, and pathological implications, this review contributes to a more comprehensive understanding of the BBB and paves the way for future research and therapeutic interventions.
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Affiliation(s)
- Hin Fong
- Faculty of Medicine, International School, Jinan University, Guangzhou 510632, China; (H.F.); (C.L.); (B.B.)
| | - Botao Zhou
- Department of Physiology, Basic Medical and Public Health School, Jinan University, Guangzhou 510632, China;
| | - Haixiao Feng
- Gies College of Business, University of Illinois Urbana-Champaign, Urbana-Champaign, IL 61801, USA;
| | - Chuoying Luo
- Faculty of Medicine, International School, Jinan University, Guangzhou 510632, China; (H.F.); (C.L.); (B.B.)
| | - Boren Bai
- Faculty of Medicine, International School, Jinan University, Guangzhou 510632, China; (H.F.); (C.L.); (B.B.)
| | - John Zhang
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA;
- Department of Neurosurgery, Loma Linda University, Loma Linda, CA 92350, USA
| | - Yuechun Wang
- Department of Physiology, Basic Medical and Public Health School, Jinan University, Guangzhou 510632, China;
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13
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Catalano M, Limatola C, Trettel F. Non-neoplastic astrocytes: key players for brain tumor progression. Front Cell Neurosci 2024; 17:1352130. [PMID: 38293652 PMCID: PMC10825036 DOI: 10.3389/fncel.2023.1352130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 12/26/2023] [Indexed: 02/01/2024] Open
Abstract
Astrocytes are highly plastic cells whose activity is essential to maintain the cerebral homeostasis, regulating synaptogenesis and synaptic transmission, vascular and metabolic functions, ions, neuro- and gliotransmitters concentrations. In pathological conditions, astrocytes may undergo transient or long-lasting molecular and functional changes that contribute to disease resolution or exacerbation. In recent years, many studies demonstrated that non-neoplastic astrocytes are key cells of the tumor microenvironment that contribute to the pathogenesis of glioblastoma, the most common primary malignant brain tumor and of secondary metastatic brain tumors. This Mini Review covers the recent development of research on non-neoplastic astrocytes as tumor-modulators. Their double-edged capability to promote cancer progression or to represent potential tools to counteract brain tumors will be discussed.
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Affiliation(s)
- Myriam Catalano
- Laboratory of Neuroimmunology, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Cristina Limatola
- Laboratory of Neuroimmunology, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- IRCCS Neuromed, Pozzilli, Italy
| | - Flavia Trettel
- Laboratory of Neuroimmunology, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
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14
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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] [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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15
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Pintwala SK, Peever J. Brain Circuits Underlying Narcolepsy. Neuroscientist 2023; 29:751-766. [PMID: 34704497 DOI: 10.1177/10738584211052263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Narcolepsy is a sleep disorder manifesting symptoms such as excessive daytime sleepiness and often cataplexy, a sudden and involuntary loss of muscle activity during wakefulness. The underlying neuropathological basis of narcolepsy is the loss of orexin neurons from the lateral hypothalamus. To date numerous animal models of narcolepsy have been produced in the laboratory, being invaluable tools for delineating the brain circuits of narcolepsy. This review will examine the evidence regarding the function of the orexin system, and how loss of this wake-promoting system manifests in excessive daytime sleepiness. This review will also outline the brain circuits controlling cataplexy, focusing on the contribution of orexin signaling loss in narcolepsy. Although our understanding of the brain circuits of narcolepsy has made great progress in recent years, much remains to be understood.
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Affiliation(s)
| | - John Peever
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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16
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Murphy-Royal C, Ching S, Papouin T. A conceptual framework for astrocyte function. Nat Neurosci 2023; 26:1848-1856. [PMID: 37857773 PMCID: PMC10990637 DOI: 10.1038/s41593-023-01448-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 09/01/2023] [Indexed: 10/21/2023]
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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17
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Jazaeri SZ, Taghizadeh G, Babaei JF, Goudarzi S, Saadatmand P, Joghataei MT, Khanahmadi Z. Aquaporin 4 beyond a water channel; participation in motor, sensory, cognitive and psychological performances, a comprehensive review. Physiol Behav 2023; 271:114353. [PMID: 37714320 DOI: 10.1016/j.physbeh.2023.114353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/15/2023] [Accepted: 09/13/2023] [Indexed: 09/17/2023]
Abstract
Aquaporin 4 (AQP4) is a protein highly expressed in the central nervous system (CNS) and peripheral nervous system (PNS) as well as various other organs, whose different sites of action indicate its importance in various functions. AQP4 has a variety of essential roles beyond water homeostasis. In this article, we have for the first time summarized different roles of AQP4 in motor and sensory functions, besides cognitive and psychological performances, and most importantly, possible physiological mechanisms by which AQP4 can exert its effects. Furthermore, we demonstrated that AQP4 participates in pathology of different neurological disorders, various effects depending on the disease type. Since neurological diseases involve a spectrum of dysfunctions and due to the difficulty of obtaining a treatment that can simultaneously affect these deficits, it is therefore suggested that future studies consider the role of this protein in different functional impairments related to neurological disorders simultaneously or separately by targeting AQP4 expression and/or polarity modulation.
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Affiliation(s)
- Seyede Zohreh Jazaeri
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Ghorban Taghizadeh
- Department of Occupational Therapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
| | - Javad Fahanik Babaei
- Electrophysiology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sepideh Goudarzi
- Experimental Medicine Research Center, Tehran University of medical Sciences, Tehran, Iran
| | - Pegah Saadatmand
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Joghataei
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Department of Innovation in Medical Education, Faculty of Medicine, Ottawa University, Ottawa, Canada.
| | - Zohreh Khanahmadi
- Department of Occupational Therapy, School of Rehabilitation Services, Isfahan University of Medical Sciences, Isfahan, Iran
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18
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Palpagama T, Mills AR, Ferguson MW, Vikas Ankeal P, Turner C, Tippett L, van der Werf B, Waldvogel HJ, Faull RLM, Kwakowsky A. Microglial and Astrocytic Responses in the Human Midcingulate Cortex in Huntington's Disease. Ann Neurol 2023; 94:895-910. [PMID: 37528539 DOI: 10.1002/ana.26753] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023]
Abstract
OBJECTIVE Patients with Huntington's disease can present with variable difficulties of motor functioning, mood, and cognition. Neurodegeneration occurs in the anterior cingulate cortex of some patients with Huntington's disease and is linked to the presentation of mood symptomatology. Neuroinflammation, perpetrated by activated microglia and astrocytes, has been reported in Huntington's disease and may contribute to disease progression and presentation. This study sought to quantify the density of mutant huntingtin protein and neuroinflammatory glial changes in the midcingulate cortex of postmortem patients with Huntington's disease and determine if either correlates with the presentation of mood, motor, or mixed symptomatology. METHODS Free-floating immunohistochemistry quantified 1C2 immunolabeling density as an indicative marker of mutant huntingtin protein, and protein and morphological markers of astrocyte (EAAT2, Cx43, and GFAP), and microglial (Iba1 and HLA-DP/DQ/DR) activation. Relationships among the level of microglial activation, mutant huntingtin burden, and case characteristics were explored using correlative analysis. RESULTS We report alterations in activated microglia number and morphology in the midcingulate cortex of Huntington's disease cases with predominant mood symptomatology. An increased proportion of activated microglia was observed in the midcingulate of all Huntington's disease cases and positively correlated with 1C2 burden. Alterations in the astrocytic glutamate transporter EAAT2 were observed in the midcingulate cortex of patients associated with mood symptoms. INTERPRETATION This study presents pathological changes in microglia and astrocytes in the midcingulate cortex in Huntington's disease, which coincide with mood symptom presentation. These findings further the understanding of neuroinflammation in Huntington's disease, a necessary step for developing inflammation-targeted therapeutics. ANN NEUROL 2023;94:895-910.
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Affiliation(s)
- Thulani Palpagama
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Aimee Rose Mills
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Mackenzie Wendy Ferguson
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | | | - Clinton Turner
- Department of Anatomical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand
| | - Lynette Tippett
- Centre for Brain Research and School of Psychology, Faculty of Sciences, University of Auckland, Auckland, New Zealand
| | - Bert van der Werf
- Department of Epidemiology and Biostatistics, Faculty of Medical and Health Sciences, School of Population Health, University of Auckland, Auckland, New Zealand
| | - Henry John Waldvogel
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Richard Lewis Maxwell Faull
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Andrea Kwakowsky
- Centre for Brain Research and Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
- Pharmacology and Therapeutics, School of Medicine, Galway Neuroscience Centre, University of Galway, Galway, Ireland
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19
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Ismail FS, Faustmann PM, Förster E, Corvace F, Faustmann TJ. Tiagabine and zonisamide differentially regulate the glial properties in an astrocyte-microglia co-culture model of inflammation. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023; 396:3253-3267. [PMID: 37231170 PMCID: PMC10567966 DOI: 10.1007/s00210-023-02538-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/16/2023] [Indexed: 05/27/2023]
Abstract
Due to the role of astrocytes and microglia in the pathophysiology of epilepsy and limited studies of antiseizure medication (ASM) effects on glial cells, we studied tiagabine (TGB) and zonisamide (ZNS) in an astrocyte-microglia co-culture model of inflammation. Different concentrations of ZNS (10, 20, 40, 100 µg/ml) or TGB (1, 10, 20, 50 µg/ml) were added to primary rat astrocytes co-cultures with 5-10% (M5, physiological conditions) or 30-40% (M30, pathological inflammatory conditions) microglia for 24 h, aiming to study glial viability, microglial activation, connexin 43 (Cx43) expression and gap-junctional coupling. ZNS led to the reduction of glial viability by only 100 µg/ml under physiological conditions. By contrast, TGB revealed toxic effects with a significant, concentration-dependent reduction of glial viability under physiological and pathological conditions. After the incubation of M30 co-cultures with 20 µg/ml TGB, the microglial activation was significantly decreased and resting microglia slightly increased, suggesting possible anti-inflammatory features of TGB under inflammatory conditions. Otherwise, ZNS caused no significant changes of microglial phenotypes. The gap-junctional coupling was significantly decreased after the incubation of M5 co-cultures with 20 and 50 µg/ml TGB, which can be related to its anti-epileptic activity under noninflammatory conditions. A significant decrease of Cx43 expression and cell-cell coupling was found after the incubation of M30 co-cultures with 10 µg/ml ZNS, suggesting additional anti-seizure effects of ZNS with the disruption of glial gap-junctional communication under inflammatory conditions. TGB and ZNS differentially regulated the glial properties. Developing novel ASMs targeting glial cells may have future potential as an "add-on" therapy to classical ASMs targeting neurons.
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Affiliation(s)
- Fatme Seval Ismail
- Department of Neurology, University Hospital Knappschaftskrankenhaus Bochum, Ruhr University Bochum, Bochum, Germany.
| | - Pedro M Faustmann
- Department of Neuroanatomy and Molecular Brain Research, Medical Faculty, Ruhr University Bochum, Bochum, Germany
| | - Eckart Förster
- Department of Neuroanatomy and Molecular Brain Research, Medical Faculty, Ruhr University Bochum, Bochum, Germany
| | - Franco Corvace
- Department of Neuroanatomy and Molecular Brain Research, Medical Faculty, Ruhr University Bochum, Bochum, Germany
| | - Timo Jendrik Faustmann
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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20
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Madeira D, Domingues J, Lopes CR, Canas PM, Cunha RA, Agostinho P. Modification of astrocytic Cx43 hemichannel activity in animal models of AD: modulation by adenosine A 2A receptors. Cell Mol Life Sci 2023; 80:340. [PMID: 37898985 PMCID: PMC10613596 DOI: 10.1007/s00018-023-04983-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/07/2023] [Accepted: 09/26/2023] [Indexed: 10/31/2023]
Abstract
Increasing evidence implicates astrocytic dysfunction in Alzheimer's disease (AD), a neurodegenerative disorder characterised by progressive cognitive loss. The accumulation of amyloid-β (Aβ) plaques is a histopathological hallmark of AD and associated with increased astrocyte reactivity. In APP/PS1 mice modelling established AD (9 months), we now show an altered astrocytic morphology and enhanced activity of astrocytic hemichannels, mainly composed by connexin 43 (Cx43). Hemichannel activity in hippocampal astrocytes is also increased in two models of early AD: (1) mice with intracerebroventricular (icv) administration of Aβ1-42, and (2) hippocampal slices superfused with Aβ1-42 peptides. In hippocampal gliosomes of APP/PS1 mice, Cx43 levels were increased, whereas mice administered icv with Aβ1-42 only displayed increased Cx43 phosphorylation levels. This suggests that hemichannel activity might be differentially modulated throughout AD progression. Additionally, we tested if adenosine A2A receptor (A2AR) blockade reversed alterations of astrocytic hemichannel activity and found that the pharmacological blockade or genetic silencing (global and astrocytic) of A2AR prevented Aβ-induced hemichannel dysregulation in hippocampal slices, although A2AR genetic silencing increased the activity of astroglial hemichannels in control conditions. In primary cultures of astrocytes, A2AR-related protective effect was shown to occur through a protein kinase C (PKC) pathway. Our results indicate that the dysfunction of hemichannel activity in hippocampal astrocytes is an early event in AD, which is modulated by A2AR.
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Affiliation(s)
- Daniela Madeira
- Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal
| | - Joana Domingues
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal
| | - Cátia R Lopes
- Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal
| | - Paula M Canas
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal
| | - Rodrigo A Cunha
- Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal
| | - Paula Agostinho
- Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal.
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Rua Larga, Polo I FMUC, First Floor, 3004-504, Coimbra, Portugal.
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21
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Mitroshina E, Kalinina E, Vedunova M. Optogenetics in Alzheimer's Disease: Focus on Astrocytes. Antioxidants (Basel) 2023; 12:1856. [PMID: 37891935 PMCID: PMC10604138 DOI: 10.3390/antiox12101856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/27/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, resulting in disability and mortality. The global incidence of AD is consistently surging. Although numerous therapeutic agents with promising potential have been developed, none have successfully treated AD to date. Consequently, the pursuit of novel methodologies to address neurodegenerative processes in AD remains a paramount endeavor. A particularly promising avenue in this search is optogenetics, enabling the manipulation of neuronal activity. In recent years, research attention has pivoted from neurons to glial cells. This review aims to consider the potential of the optogenetic correction of astrocyte metabolism as a promising strategy for correcting AD-related disorders. The initial segment of the review centers on the role of astrocytes in the genesis of neurodegeneration. Astrocytes have been implicated in several pathological processes associated with AD, encompassing the clearance of β-amyloid, neuroinflammation, excitotoxicity, oxidative stress, and lipid metabolism (along with a critical role in apolipoprotein E function). The effect of astrocyte-neuronal interactions will also be scrutinized. Furthermore, the review delves into a number of studies indicating that changes in cellular calcium (Ca2+) signaling are one of the causes of neurodegeneration. The review's latter section presents insights into the application of various optogenetic tools to manipulate astrocytic function as a means to counteract neurodegenerative changes.
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Affiliation(s)
- Elena Mitroshina
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Avenue, 603022 Nizhny Novgorod, Russia (M.V.)
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22
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Freitas-Andrade M, Comin CH, Van Dyken P, Ouellette J, Raman-Nair J, Blakeley N, Liu QY, Leclerc S, Pan Y, Liu Z, Carrier M, Thakur K, Savard A, Rurak GM, Tremblay MÈ, Salmaso N, da F Costa L, Coppola G, Lacoste B. Astroglial Hmgb1 regulates postnatal astrocyte morphogenesis and cerebrovascular maturation. Nat Commun 2023; 14:4965. [PMID: 37587100 PMCID: PMC10432480 DOI: 10.1038/s41467-023-40682-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/31/2023] [Indexed: 08/18/2023] Open
Abstract
Astrocytes are intimately linked with brain blood vessels, an essential relationship for neuronal function. However, astroglial factors driving these physical and functional associations during postnatal brain development have yet to be identified. By characterizing structural and transcriptional changes in mouse cortical astrocytes during the first two postnatal weeks, we find that high-mobility group box 1 (Hmgb1), normally upregulated with injury and involved in adult cerebrovascular repair, is highly expressed in astrocytes at birth and then decreases rapidly. Astrocyte-selective ablation of Hmgb1 at birth affects astrocyte morphology and endfoot placement, alters distribution of endfoot proteins connexin43 and aquaporin-4, induces transcriptional changes in astrocytes related to cytoskeleton remodeling, and profoundly disrupts endothelial ultrastructure. While lack of astroglial Hmgb1 does not affect the blood-brain barrier or angiogenesis postnatally, it impairs neurovascular coupling and behavior in adult mice. These findings identify astroglial Hmgb1 as an important player in postnatal gliovascular maturation.
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Affiliation(s)
| | - Cesar H Comin
- Federal University of São Carlos, Department of Computer Science, São Carlos, Brazil
| | - Peter Van Dyken
- Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Julie Ouellette
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Joanna Raman-Nair
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Nicole Blakeley
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Qing Yan Liu
- National Research Council of Canada, Human Health and Therapeutics, Ottawa, ON, Canada
- Department of Biochemistry Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Sonia Leclerc
- National Research Council of Canada, Human Health and Therapeutics, Ottawa, ON, Canada
| | - Youlian Pan
- Digital Technologies, National Research Council of Canada, Ottawa, ON, Canada
| | - Ziying Liu
- Digital Technologies, National Research Council of Canada, Ottawa, ON, Canada
| | - Micaël Carrier
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Karan Thakur
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Alexandre Savard
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Gareth M Rurak
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Natalina Salmaso
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Luciano da F Costa
- University of São Paulo, São Carlos Institute of Physics, FCM-USP, São Paulo, Brazil
| | | | - Baptiste Lacoste
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada.
- Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.
- University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada.
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23
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Gebicke-Haerter PJ. The computational power of the human brain. Front Cell Neurosci 2023; 17:1220030. [PMID: 37608987 PMCID: PMC10441807 DOI: 10.3389/fncel.2023.1220030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/05/2023] [Indexed: 08/24/2023] Open
Abstract
At the end of the 20th century, analog systems in computer science have been widely replaced by digital systems due to their higher computing power. Nevertheless, the question keeps being intriguing until now: is the brain analog or digital? Initially, the latter has been favored, considering it as a Turing machine that works like a digital computer. However, more recently, digital and analog processes have been combined to implant human behavior in robots, endowing them with artificial intelligence (AI). Therefore, we think it is timely to compare mathematical models with the biology of computation in the brain. To this end, digital and analog processes clearly identified in cellular and molecular interactions in the Central Nervous System are highlighted. But above that, we try to pinpoint reasons distinguishing in silico computation from salient features of biological computation. First, genuinely analog information processing has been observed in electrical synapses and through gap junctions, the latter both in neurons and astrocytes. Apparently opposed to that, neuronal action potentials (APs) or spikes represent clearly digital events, like the yes/no or 1/0 of a Turing machine. However, spikes are rarely uniform, but can vary in amplitude and widths, which has significant, differential effects on transmitter release at the presynaptic terminal, where notwithstanding the quantal (vesicular) release itself is digital. Conversely, at the dendritic site of the postsynaptic neuron, there are numerous analog events of computation. Moreover, synaptic transmission of information is not only neuronal, but heavily influenced by astrocytes tightly ensheathing the majority of synapses in brain (tripartite synapse). At least at this point, LTP and LTD modifying synaptic plasticity and believed to induce short and long-term memory processes including consolidation (equivalent to RAM and ROM in electronic devices) have to be discussed. The present knowledge of how the brain stores and retrieves memories includes a variety of options (e.g., neuronal network oscillations, engram cells, astrocytic syncytium). Also epigenetic features play crucial roles in memory formation and its consolidation, which necessarily guides to molecular events like gene transcription and translation. In conclusion, brain computation is not only digital or analog, or a combination of both, but encompasses features in parallel, and of higher orders of complexity.
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Affiliation(s)
- Peter J. Gebicke-Haerter
- Institute of Psychopharmacology, Central Institute of Mental Health, Faculty of Medicine, University of Heidelberg, Mannheim, Germany
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24
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Sun N, Cui WQ, Min XM, Zhang GM, Liu JZ, Wu HY. A new perspective on hippocampal synaptic plasticity and post-stroke depression. Eur J Neurosci 2023; 58:2961-2984. [PMID: 37518943 DOI: 10.1111/ejn.16093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/01/2023] [Accepted: 07/03/2023] [Indexed: 08/01/2023]
Abstract
Post-stroke depression, a common complication after stroke, severely affects the recovery and quality of life of patients with stroke. Owing to its complex mechanisms, post-stroke depression treatment remains highly challenging. Hippocampal synaptic plasticity is one of the key factors leading to post-stroke depression; however, the precise molecular mechanisms remain unclear. Numerous studies have found that neurotrophic factors, protein kinases and neurotransmitters influence depressive behaviour by modulating hippocampal synaptic plasticity. This review further elaborates on the role of hippocampal synaptic plasticity in post-stroke depression by summarizing recent research and analysing possible molecular mechanisms. Evidence for the correlation between hippocampal mechanisms and post-stroke depression helps to better understand the pathological process of post-stroke depression and improve its treatment.
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Affiliation(s)
- Ning Sun
- First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Wen-Qiang Cui
- Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xiao-Man Min
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Guang-Ming Zhang
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jia-Zheng Liu
- College of Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Hong-Yun Wu
- Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
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25
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Cullen PF, Sun D. Astrocytes of the eye and optic nerve: heterogeneous populations with unique functions mediate axonal resilience and vulnerability to glaucoma. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1217137. [PMID: 37829657 PMCID: PMC10569075 DOI: 10.3389/fopht.2023.1217137] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
The role of glia, particularly astrocytes, in mediating the central nervous system's response to injury and neurodegenerative disease is an increasingly well studied topic. These cells perform myriad support functions under physiological conditions but undergo behavioral changes - collectively referred to as 'reactivity' - in response to the disruption of neuronal homeostasis from insults, including glaucoma. However, much remains unknown about how reactivity alters disease progression - both beneficially and detrimentally - and whether these changes can be therapeutically modulated to improve outcomes. Historically, the heterogeneity of astrocyte behavior has been insufficiently addressed under both physiological and pathological conditions, resulting in a fragmented and often contradictory understanding of their contributions to health and disease. Thanks to increased focus in recent years, we now know this heterogeneity encompasses both intrinsic variation in physiological function and insult-specific changes that vary between pathologies. Although previous studies demonstrate astrocytic alterations in glaucoma, both in human disease and animal models, generally these findings do not conclusively link astrocytes to causative roles in neuroprotection or degeneration, rather than a subsequent response. Efforts to bolster our understanding by drawing on knowledge of brain astrocytes has been constrained by the primacy in the literature of findings from peri-synaptic 'gray matter' astrocytes, whereas much early degeneration in glaucoma occurs in axonal regions populated by fibrous 'white matter' astrocytes. However, by focusing on findings from astrocytes of the anterior visual pathway - those of the retina, unmyelinated optic nerve head, and myelinated optic nerve regions - we aim to highlight aspects of their behavior that may contribute to axonal vulnerability and glaucoma progression, including roles in mitochondrial turnover and energy provisioning. Furthermore, we posit that astrocytes of the retina, optic nerve head and myelinated optic nerve, although sharing developmental origins and linked by a network of gap junctions, may be best understood as distinct populations residing in markedly different niches with accompanying functional specializations. A closer investigation of their behavioral repertoires may elucidate not only their role in glaucoma, but also mechanisms to induce protective behaviors that can impede the progressive axonal damage and retinal ganglion cell death that drive vision loss in this devastating condition.
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Affiliation(s)
- Paul F. Cullen
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Daniel Sun
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
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26
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Bedner P, Steinhäuser C. Role of Impaired Astrocyte Gap Junction Coupling in Epileptogenesis. Cells 2023; 12:1669. [PMID: 37371139 DOI: 10.3390/cells12121669] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/25/2023] [Accepted: 06/19/2023] [Indexed: 06/29/2023] Open
Abstract
The gap-junction-coupled astroglial network plays a central role in the regulation of neuronal activity and synchronisation, but its involvement in the pathogenesis of neuronal diseases is not yet understood. Here, we present the current state of knowledge about the impact of impaired glial coupling in the development and progression of epilepsy and discuss whether astrocytes represent alternative therapeutic targets. We focus mainly on temporal lobe epilepsy (TLE), which is the most common form of epilepsy in adults and is characterised by high therapy resistance. Functional data from TLE patients and corresponding experimental models point to a complete loss of astrocytic coupling, but preservation of the gap junction forming proteins connexin43 and connexin30 in hippocampal sclerosis. Several studies further indicate that astrocyte uncoupling is a causal event in the initiation of TLE, as it occurs very early in epileptogenesis, clearly preceding dysfunctional changes in neurons. However, more research is needed to fully understand the role of gap junction channels in epilepsy and to develop safe and effective therapeutic strategies targeting astrocytes.
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Affiliation(s)
- Peter Bedner
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
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27
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Watanabe A, Guo C, Sjöström PJ. The developmental profile of visual cortex astrocytes. iScience 2023; 26:106828. [PMID: 37250801 PMCID: PMC10212985 DOI: 10.1016/j.isci.2023.106828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 03/08/2023] [Accepted: 05/03/2023] [Indexed: 05/31/2023] Open
Abstract
We investigated how astrocytes in layer 5 mouse visual cortex mature over postnatal days (P) 3-50. Across this age range, resting membrane potential increased, input resistance decreased, and membrane responses became more passive with age. Two-photon (2p) and confocal imaging of dye-loaded cells revealed that gap-junction coupling increased starting ∼P7. Morphological reconstructions revealed increased branch density but shorter branches after P20, suggesting that astrocyte branches may get pruned as tiling is established. Finally, we visualized spontaneous Ca2+ transients with 2p microscopy and found that Ca2+ events decorrelated, became more frequent and briefer with age. As astrocytes mature, spontaneous Ca2+ activity thus changes from relatively cell-wide, synchronous waves to local transients. Several astrocyte properties were stably mature from ∼P15, coinciding with eye opening, although morphology continued to develop. Our findings provide a descriptive foundation of astrocyte maturation, useful for the study of astrocytic impact on visual cortex critical period plasticity.
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Affiliation(s)
- Airi Watanabe
- Centre for Research in Neuroscience, Brain Repair and Integrative Neuroscience Program, Department of Medicine, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, QC H3G 1A4, Canada
- Integrated Program in Neuroscience, Irving Ludmer Building, McGill University, 1033 Pine Avenue West, Montreal, QC H3A 1A1, Canada
| | - Connie Guo
- Centre for Research in Neuroscience, Brain Repair and Integrative Neuroscience Program, Department of Medicine, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, QC H3G 1A4, Canada
- Department of Anatomy and Cell Biology, Faculty of Science, McGill University, Strathcona Anatomy and Dentistry Building, 3640 University Street, Montreal, QC H3A 0C7, Canada
| | - Per Jesper Sjöström
- Centre for Research in Neuroscience, Brain Repair and Integrative Neuroscience Program, Department of Medicine, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, QC H3G 1A4, Canada
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28
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Lantz MJ, Roberts AM, Delgado DD, Nichols RA. The neuroprotective N-terminal amyloid-β core hexapeptide reverses reactive gliosis and gliotoxicity in Alzheimer's disease pathology models. J Neuroinflammation 2023; 20:129. [PMID: 37245024 DOI: 10.1186/s12974-023-02807-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 05/16/2023] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by accumulation of extracellular amyloid beta (Aβ) and intracellular neurofibrillary tangles, leading to chronic activation of astrocytes and microglia and persistent neuroinflammation. Aβ-linked activation of microglia and astrocytes leads to increased intracellular calcium and production of proinflammatory cytokines, impacting the progression of neurodegeneration. An N-terminal Aβ fragment (Aβ1-15) and a shorter hexapeptide core sequence within the N-Aβ fragment (N-Aβcore: Aβ10-15) have previously been shown to protect against Aβ-induced mitochondrial dysfunction, oxidative stress and apoptosis in neurons and rescue synaptic and spatial memory deficits in an APP/PSEN1 mouse model. Here, we hypothesized that the N-Aβ fragment and N-Aβcore are protective against Aβ-induced gliotoxicity, promoting a neuroprotective environment and potentially alleviating the characteristically persistent neuroinflammation present in AD. METHODS We treated ex vivo organotypic brain slice cultures from an aged familial AD mouse model, 5xFAD, with the N-Aβcore and used immunocytochemistry to assess the impact on astrogliosis and microgliosis and alterations in synaptophysin-positive puncta engulfed by microglia. Isolated neuron/glia cultures, mixed glial cultures or a microglial cell line were treated with oligomeric human Aβ at concentrations mimicking the pathogenic concentrations (μM) observed in AD in the absence or presence of the non-toxic N-terminal Aβ fragments. Resultant changes in synaptic density, gliosis, oxidative stress, mitochondrial dysfunction, apoptosis, and the expression and release of proinflammatory markers were then determined. RESULTS We demonstrate that the N-terminal Aβ fragments mitigated the phenotypic switch leading to astrogliosis and microgliosis induced by pathological concentrations of Aβ in mixed glial cultures and organotypic brain slice cultures from the transgenic 5xFAD mouse model, while protecting against Aβ-induced oxidative stress, mitochondrial dysfunction and apoptosis in isolated astrocytes and microglia. Moreover, the addition of the N-Aβcore attenuated the expression and release of proinflammatory mediators in microglial cells activated by Aβ and rescued microglia-mediated loss of synaptic elements induced by pathological levels of Aβ. CONCLUSIONS Together, these findings indicate the protective functions of the N-terminal Aβ fragments extend to reactive gliosis and gliotoxicity induced by Aβ, by preventing or reversing glial reactive states indicative of neuroinflammation and synaptic loss central to AD pathogenesis.
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Affiliation(s)
- Megan J Lantz
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Alyssa M Roberts
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Donovan D Delgado
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Robert A Nichols
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA.
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29
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Yao J, Chen C, Guo Y, Yang Y, Liu X, Chu S, Ai Q, Zhang Z, Lin M, Yang S, Chen N. A Review of Research on the Association between Neuron-Astrocyte Signaling Processes and Depressive Symptoms. Int J Mol Sci 2023; 24:ijms24086985. [PMID: 37108148 PMCID: PMC10139177 DOI: 10.3390/ijms24086985] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/02/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Depression is a mental illness that has a serious negative impact on physical and mental health. The pathophysiology of depression is still unknown, and therapeutic medications have drawbacks, such as poor effectiveness, strong dependence, adverse drug withdrawal symptoms, and harmful side effects. Therefore, the primary purpose of contemporary research is to understand the exact pathophysiology of depression. The connection between astrocytes, neurons, and their interactions with depression has recently become the focus of great research interest. This review summarizes the pathological changes of neurons and astrocytes, and their interactions in depression, including the alterations of mid-spiny neurons and pyramidal neurons, the alterations of astrocyte-related biomarkers, and the alterations of gliotransmitters between astrocytes and neurons. In addition to providing the subjects of this research and suggestions for the pathogenesis and treatment techniques of depression, the intention of this article is to more clearly identify links between neuronal-astrocyte signaling processes and depressive symptoms.
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Affiliation(s)
- Jiao Yao
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
- Key Laboratory of Modern Research of TCM, Education Department of Hunan Province, Changsha 410208, China
| | - Cong Chen
- School of Traditional Chinese Medicine, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Yi Guo
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
- School of Acupuncture & Tuina and Rehabilitation, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Yantao Yang
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Xinya Liu
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Shifeng Chu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Qidi Ai
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
- Key Laboratory of Modern Research of TCM, Education Department of Hunan Province, Changsha 410208, China
| | - Zhao Zhang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Meiyu Lin
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Songwei Yang
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
- Key Laboratory of Modern Research of TCM, Education Department of Hunan Province, Changsha 410208, China
| | - Naihong Chen
- Hunan Engineering Technology Center of Standardization and Function of Chinese Herbal Decoction Pieces, College of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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30
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Soto JS, Jami-Alahmadi Y, Chacon J, Moye SL, Diaz-Castro B, Wohlschlegel JA, Khakh BS. Astrocyte-neuron subproteomes and obsessive-compulsive disorder mechanisms. Nature 2023; 616:764-773. [PMID: 37046092 PMCID: PMC10132990 DOI: 10.1038/s41586-023-05927-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 03/07/2023] [Indexed: 04/14/2023]
Abstract
Astrocytes and neurons extensively interact in the brain. Identifying astrocyte and neuron proteomes is essential for elucidating the protein networks that dictate their respective contributions to physiology and disease. Here we used cell-specific and subcompartment-specific proximity-dependent biotinylation1 to study the proteomes of striatal astrocytes and neurons in vivo. We evaluated cytosolic and plasma membrane compartments for astrocytes and neurons to discover how these cells differ at the protein level in their signalling machinery. We also assessed subcellular compartments of astrocytes, including end feet and fine processes, to reveal their subproteomes and the molecular basis of essential astrocyte signalling and homeostatic functions. Notably, SAPAP3 (encoded by Dlgap3), which is associated with obsessive-compulsive disorder (OCD) and repetitive behaviours2-8, was detected at high levels in striatal astrocytes and was enriched within specific astrocyte subcompartments where it regulated actin cytoskeleton organization. Furthermore, genetic rescue experiments combined with behavioural analyses and molecular assessments in a mouse model of OCD4 lacking SAPAP3 revealed distinct contributions of astrocytic and neuronal SAPAP3 to repetitive and anxiety-related OCD-like phenotypes. Our data define how astrocytes and neurons differ at the protein level and in their major signalling pathways. Moreover, they reveal how astrocyte subproteomes vary between physiological subcompartments and how both astrocyte and neuronal SAPAP3 mechanisms contribute to OCD phenotypes in mice. Our data indicate that therapeutic strategies that target both astrocytes and neurons may be useful to explore in OCD and potentially other brain disorders.
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Affiliation(s)
- Joselyn S Soto
- Department of Physiology, University of California, Los Angeles, CA, USA
| | - Yasaman Jami-Alahmadi
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Jakelyn Chacon
- Department of Physiology, University of California, Los Angeles, CA, USA
| | - Stefanie L Moye
- Department of Physiology, University of California, Los Angeles, CA, USA
| | - Blanca Diaz-Castro
- Department of Physiology, University of California, Los Angeles, CA, USA
- UK Dementia Research Institute and Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - James A Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Baljit S Khakh
- Department of Physiology, University of California, Los Angeles, CA, USA.
- Department of Neurobiology, University of California, Los Angeles, CA, USA.
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31
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Chhichholiya Y, Ruthuparna M, Velagaleti H, Munshi A. Brain metastasis in breast cancer: focus on genes and signaling pathways involved, blood-brain barrier and treatment strategies. Clin Transl Oncol 2023; 25:1218-1241. [PMID: 36897508 DOI: 10.1007/s12094-022-03050-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/12/2022] [Indexed: 03/11/2023]
Abstract
Breast cancer (BC) is one of the most prevalent types of cancer in women. Despite advancement in early detection and efficient treatment, recurrence and metastasis continue to pose a significant risk to the life of BC patients. Brain metastasis (BM) reported in 17-20 percent of BC patients is considered as a major cause of mortality and morbidity in these patients. BM includes various steps from primary breast tumor to secondary tumor formation. Various steps involved are primary tumor formation, angiogenesis, invasion, extravasation, and brain colonization. Genes involved in different pathways have been reported to be associated with BC cells metastasizing to the brain. ADAM8 gene, EN1 transcription factor, WNT, and VEGF signaling pathway have been associated with primary breast tumor; MMP1, COX2, XCR4, PI3k/Akt, ERK and MAPK pathways in angiogenesis; Noth, CD44, Zo-1, CEMIP, S0X2 and OLIG2 are involved in invasion, extravasation and colonization, respectively. In addition, the blood-brain barrier is also a key factor in BM. Dysregulation of cell junctions, tumor microenvironment and loss of function of microglia leads to BBB disruption ultimately resulting in BM. Various therapeutic strategies are currently used to control the BM in BC. Oncolytic virus therapy, immune checkpoint inhibitors, mTOR-PI3k inhibitors and immunotherapy have been developed to target various genes involved in BM in BC. In addition, RNA interference (RNAi) and CRISPR/Cas9 are novel interventions in the field of BCBM where research to validate these and clinical trials are being carried out. Gaining a better knowledge of metastasis biology is critical for establishing better treatment methods and attaining long-term therapeutic efficacies against BC. The current review has been compiled with an aim to evaluate the role of various genes and signaling pathways involved in multiple steps of BM in BC. The therapeutic strategies being used currently and the novel ones being explored to control BM in BC have also been discussed at length.
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Affiliation(s)
- Yogita Chhichholiya
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Malayil Ruthuparna
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Harini Velagaleti
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India.
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Yao D, Zhang R, Xie M, Ding F, Wang M, Wang W. Updated Understanding of the Glial-Vascular Unit in Central Nervous System Disorders. Neurosci Bull 2023; 39:503-518. [PMID: 36374471 PMCID: PMC10043098 DOI: 10.1007/s12264-022-00977-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/04/2022] [Indexed: 11/16/2022] Open
Abstract
The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.
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Affiliation(s)
- Di Yao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ruoying Zhang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Minjie Xie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Fengfei Ding
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Minghuan Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Key Laboratory of Neurological Diseases of the Chinese Ministry of Education, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Ikoma Y, Sasaki D, Matsui K. Local brain environment changes associated with epileptogenesis. Brain 2023; 146:576-586. [PMID: 36423658 DOI: 10.1093/brain/awac355] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/30/2022] [Accepted: 09/08/2022] [Indexed: 11/27/2022] Open
Abstract
Plastic change of the neuronal system has traditionally been assumed to be governed primarily by the long-term potentiation/depression mechanisms of synaptic transmission. However, a rather simple shift in the ambient ion, transmitter and metabolite concentrations could have a pivotal role in generating plasticity upon the physiological process of learning and memory. Local brain environment and metabolic changes could also be the cause and consequences of the pathogenesis leading to epilepsy. Governing of the local brain environment is the primal function of astrocytes. The metabolic state of the entire brain is strongly linked to the activity of the lateral hypothalamus. In this study, plastic change of astrocyte reactions in the lateral hypothalamus was examined using epileptogenesis as an extreme form of plasticity. Fluorescent sensors for calcium or pH expressed in astrocytes were examined for up to one week by in vivo fibre photometry in freely moving transgenic male mice. Optical fluctuations on a timescale of seconds is difficult to assess because these signals are heavily influenced by local brain blood volume changes and pH changes. Using a newly devised method for the analysis of the optical signals, changes in Ca2+ and pH in astrocytes and changes in local brain blood volume associated with hippocampal-stimulated epileptic seizures were extracted. Following a transient alkaline shift in the astrocyte triggered by neuronal hyperactivity, a prominent acidic shift appeared in response to intensified seizure which developed with kindling. The acidic shift was unexpected as transient increase in local brain blood volume was observed in response to intensified seizures, which should lead to efficient extrusion of the acidic CO2. The acidic shift could be a result of glutamate transporter activity and/or due to the increased metabolic load of astrocytes leading to increased CO2 and lactate production. This acidic shift may trigger additional gliotransmitter release from astrocytes leading to the exacerbation of epilepsy. As all cellular enzymic reactions are influenced by Ca2+ and pH, changes in these parameters could also have an impact on the neuronal circuit activity. Thus, controlling the astrocyte pH and/or Ca2+ could be a new therapeutic target for treatment of epilepsy or prevention of undesired plasticity associated with epileptogenesis.
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Affiliation(s)
- Yoko Ikoma
- Super-network Brain Physiology Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Daichi Sasaki
- Super-network Brain Physiology Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Ko Matsui
- Super-network Brain Physiology Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan.,Super-network Brain Physiology, Graduate School of Medicine, Tohoku University, Sendai 980-8577, Japan
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Progress in targeting PTEN/PI3K/Akt axis in glioblastoma therapy: Revisiting molecular interactions. Biomed Pharmacother 2023; 158:114204. [PMID: 36916430 DOI: 10.1016/j.biopha.2022.114204] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/16/2022] [Accepted: 12/30/2022] [Indexed: 01/05/2023] Open
Abstract
Glioblastoma (GBM) is one of the most malignant cancers of central nervous system and due to its sensitive location, surgical resection has high risk and therefore, chemotherapy and radiotherapy are utilized for its treatment. However, chemoresistance and radio-resistance are other problems in GBM treatment. Hence, new therapies based on genes are recommended for treatment of GBM. PTEN is a tumor-suppressor operator in cancer that inhibits PI3K/Akt/mTOR axis in diminishing growth, metastasis and drug resistance. In the current review, the function of PTEN/PI3K/Akt axis in GBM progression is evaluated. Mutation or depletion of PTEN leads to increase in GBM progression. Low expression level of PTEN mediates poor prognosis in GBM and by increasing proliferation and invasion, promotes malignancy of tumor cells. Moreover, loss of PTEN signaling can result in therapy resistance in GBM. Activation of PTEN signaling impairs GBM metabolism via glycolysis inhibition. In contrast to PTEN, PI3K/Akt signaling has oncogenic function and during tumor progression, expression level of PI3K/Akt enhances. PI3K/Akt signaling shows positive association with oncogenic pathways and its expression similar to PTEN signaling, is regulated by non-coding RNAs. PTEN upregulation and PI3K/Akt signaling inhibition by anti-cancer agents can be beneficial in interfering GBM progression. This review emphasizes on the signaling networks related to PTEN/PI3K/Akt and provides new insights for targeting this axis in effective GBM treatment.
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Xie M, Su C. Microenvironment and the progress of immunotherapy in clinical practice of NSCLC brain metastasis. Front Oncol 2023; 12:1006284. [PMID: 36761422 PMCID: PMC9902941 DOI: 10.3389/fonc.2022.1006284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 12/28/2022] [Indexed: 01/25/2023] Open
Abstract
One of the most frequent distant metastases of lung cancer occurs in the brain. The average natural survival duration for patients with lung cancer who have brain metastases is about 1 to 2 months. Knowledge about brain metastases is currently restricted since they are more difficult to acquire than other metastases. This review begins with an analysis of the immune microenvironment of brain metastases; focuses primarily on the functions of microglia, astrocytes, neurons, and tumor-infiltrating lymphocytes in the microenvironment of brain metastases; and offers an atlas of the immune microenvironment of brain metastases involving significant cells. In an effort to give researchers new research ideas, the study also briefly covers how immunotherapy for non-small cell lung cancer with brain metastases is currently faring.
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Gudkov SV, Burmistrov DE, Kondakova EV, Sarimov RM, Yarkov RS, Franceschi C, Vedunova MV. An emerging role of astrocytes in aging/neuroinflammation and gut-brain axis with consequences on sleep and sleep disorders. Ageing Res Rev 2023; 83:101775. [PMID: 36334910 DOI: 10.1016/j.arr.2022.101775] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 10/05/2022] [Accepted: 10/30/2022] [Indexed: 11/18/2022]
Abstract
Understanding the role of astrocytes in the central nervous system has changed dramatically over the last decade. The accumulating findings indicate that glial cells are involved not only in the maintenance of metabolic and ionic homeostasis and in the implementation of trophic functions but also in cognitive functions and information processing in the brain. Currently, there are some controversies regarding the role of astrocytes in complex processes such as aging of the nervous system and the pathogenesis of age-related neurodegenerative diseases. Many findings confirm the important functional role of astrocytes in age-related brain changes, including sleep disturbance and the development of neurodegenerative diseases and particularly Alzheimer's disease. Until recent years, neurobiological research has focused mainly on neuron-glial interactions, in which individual astrocytes locally modulate neuronal activity and communication between neurons. The review considers the role of astrocytes in the physiology of sleep and as an important "player" in the development of neurodegenerative diseases. In addition, the features of the astrocytic network reorganization during aging are discussed.
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Affiliation(s)
- Sergey V Gudkov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia; Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Dmitriy E Burmistrov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia.
| | - Elena V Kondakova
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Ruslan M Sarimov
- Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov str., 119991 Moscow, Russia.
| | - Roman S Yarkov
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Claudio Franceschi
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
| | - Maria V Vedunova
- Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin ave., 603022 Nizhny Novgorod, Russia.
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Degl’Innocenti E, Dell’Anno MT. Human and mouse cortical astrocytes: a comparative view from development to morphological and functional characterization. Front Neuroanat 2023; 17:1130729. [PMID: 37139179 PMCID: PMC10150887 DOI: 10.3389/fnana.2023.1130729] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/28/2023] [Indexed: 05/05/2023] Open
Abstract
The vision of astroglia as a bare scaffold to neuronal circuitry has been largely overturned. Astrocytes exert a neurotrophic function, but also take active part in supporting synaptic transmission and in calibrating blood circulation. Many aspects of their functioning have been unveiled from studies conducted in murine models, however evidence is showing many differences between mouse and human astrocytes starting from their development and encompassing morphological, transcriptomic and physiological variations when they achieve complete maturation. The evolutionary race toward superior cognitive abilities unique to humans has drastically impacted neocortex structure and, together with neuronal circuitry, astrocytes have also been affected with the acquisition of species-specific properties. In this review, we summarize diversities between murine and human astroglia, with a specific focus on neocortex, in a panoramic view that starts with their developmental origin to include all structural and molecular differences that mark the uniqueness of human astrocytes.
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Affiliation(s)
- Elisa Degl’Innocenti
- Fondazione Pisana per la Scienza ONLUS, San Giuliano Terme, Italy
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Maria Teresa Dell’Anno
- Fondazione Pisana per la Scienza ONLUS, San Giuliano Terme, Italy
- *Correspondence: Maria Teresa Dell’Anno,
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Hasan M, Lei Z, Akter M, Iqbal Z, Usaila F, Ramkrishnan AS, Li Y. Chemogenetic activation of astrocytes promotes remyelination and restores cognitive deficits in visceral hypersensitive rats. iScience 2022; 26:105840. [PMID: 36619970 PMCID: PMC9812719 DOI: 10.1016/j.isci.2022.105840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 04/20/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Using a well-established chronic visceral hypersensitivity (VH) rat model, we characterized the decrease of myelin basic protein, reduced number of mature oligodendrocytes (OLs), and hypomyelination in the anterior cingulate cortex (ACC). The results of rat gambling test showed impaired decision-making, and the results of electrophysiological studies showed desynchronization in the ACC to basolateral amygdala (BLA) neural circuitry. Astrocytes release various factors that modulate oligodendrocyte progenitor cell proliferation and myelination. Astrocytic Gq-modulation through expression of hM3Dq facilitated oligodendrocyte progenitor cell proliferation and OL differentiation, and enhanced ACC myelination in VH rats. Activating astrocytic Gq rescued impaired decision-making and desynchronization in ACC-BLA. These data indicate that ACC hypomyelination is an important component of impaired decision-making and network desynchronization in VH. Astrocytic Gq activity plays a significant role in oligodendrocyte myelination and decision-making behavior in VH. Insights from these studies have potential for interventions in myelin-related diseases such as chronic pain-associated cognitive disorders.
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Affiliation(s)
- Mahadi Hasan
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Zhuogui Lei
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China,Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong SAR, China
| | - Mastura Akter
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Zafar Iqbal
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China,Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong SAR, China
| | - Faeeqa Usaila
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Aruna Surendran Ramkrishnan
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Ying Li
- Department of Neuroscience, City University of Hong Kong, Hong Kong SAR, China,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China,Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong SAR, China,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong SAR, China,Corresponding author
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Pechlivanidou M, Kousiappa I, Angeli S, Sargiannidou I, Koupparis AM, Papacostas SS, Kleopa KA. Glial Gap Junction Pathology in the Spinal Cord of the 5xFAD Mouse Model of Early-Onset Alzheimer's Disease. Int J Mol Sci 2022; 23:ijms232415597. [PMID: 36555237 PMCID: PMC9779687 DOI: 10.3390/ijms232415597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/22/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
Gap junctions (GJs) are specialized transmembrane channels assembled by two hemi-channels of six connexin (Cx) proteins that facilitate neuroglial crosstalk in the central nervous system (CNS). Previous studies confirmed the crucial role of glial GJs in neurodegenerative disorders with dementia or motor dysfunction including Alzheimer's disease (AD). The aim of this study was to examine the alterations in astrocyte and related oligodendrocyte GJs in association with Aβ plaques in the spinal cord of the 5xFAD mouse model of AD. Our analysis revealed abundant Aβ plaque deposition, activated microglia, and astrogliosis in 12-month-old (12M) 5xFAD mice, with significant impairment of motor performance starting from 3-months (3M) of age. Additionally, 12M 5xFAD mice displayed increased immunoreactivity of astroglial Cx43 and Cx30 surrounding Aβ plaques and higher protein levels, indicating upregulated astrocyte-to-astrocyte GJ connectivity. In addition, they demonstrated increased numbers of mature CC1-positive and precursor oligodendrocytes (OPCs) with higher immunoreactivity of Cx47-positive GJs in individual cells. Moreover, total Cx47 protein levels were significantly elevated in 12M 5xFAD, reflecting increased oligodendrocyte-to-oligodendrocyte Cx47-Cx47 GJ connectivity. In contrast, we observed a marked reduction in Cx32 protein levels in 12M 5xFAD spinal cords compared with controls, while qRT-PCR analysis revealed a significant upregulation in Cx32 mRNA levels. Finally, myelin deficits were found focally in the areas occupied by Aβ plaques, whereas axons themselves remained preserved. Overall, our data provide novel insights into the altered glial GJ expression in the spinal cord of the 5xFAD model of AD and the implicated role of GJ pathology in neurodegeneration. Further investigation to understand the functional consequences of these extensive alterations in oligodendrocyte-astrocyte (O/A) GJ connectivity is warranted.
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Affiliation(s)
- Maria Pechlivanidou
- Neurobiology Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
| | - Ioanna Kousiappa
- Neurobiology Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
| | - Stella Angeli
- Medical School, University of Nicosia, Nicosia 2414, Cyprus
| | - Irene Sargiannidou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
| | - Andreas M. Koupparis
- Neurobiology Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Epilepsy Centre, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Dementia and Cognitive Disorders Centre, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
| | - Savvas S. Papacostas
- Neurobiology Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Medical School, University of Nicosia, Nicosia 2414, Cyprus
- Epilepsy Centre, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Dementia and Cognitive Disorders Centre, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
| | - Kleopas A. Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Center for Neuromuscular Disorders, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Center for Multiple Sclerosis and Related Disorders, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
- Correspondence:
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Benedikt J, Malpica-Nieves CJ, Rivera Y, Méndez-González M, Nichols CG, Veh RW, Eaton MJ, Skatchkov SN. The Polyamine Spermine Potentiates the Propagation of Negatively Charged Molecules through the Astrocytic Syncytium. Biomolecules 2022; 12:biom12121812. [PMID: 36551240 PMCID: PMC9775384 DOI: 10.3390/biom12121812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/16/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
The interest in astrocytes, the silent brain cells that accumulate polyamines (PAs), is growing. PAs exert anti-inflammatory, antioxidant, antidepressant, neuroprotective, and other beneficial effects, including increasing longevity in vivo. Unlike neurons, astrocytes are extensively coupled to others via connexin (Cx) gap junctions (GJs). Although there are striking modulatory effects of PAs on neuronal receptors and channels, PA regulation of the astrocytic GJs is not well understood. We studied GJ-propagation using molecules of different (i) electrical charge, (ii) structure, and (iii) molecular weight. Loading single astrocytes with patch pipettes containing membrane-impermeable dyes, we observed that (i) even small molecules do not easily permeate astrocytic GJs, (ii) the ratio of the charge to weight of these molecules is the key determinant of GJ permeation, (iii) the PA spermine (SPM) induced the propagation of negatively charged molecules via GJs, (iv) while no effects were observed on propagation of macromolecules with net-zero charge. The GJ uncoupler carbenoxolone (CBX) blocked such propagation. Taken together, these findings indicate that SPM is essential for astrocytic GJ communication and selectively facilitates intracellular propagation via GJs for negatively charged molecules through glial syncytium.
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Affiliation(s)
- Jan Benedikt
- Department of Physiology, Universidad Central del Caribe, Bayamón, PR 00956, USA
| | - Christian J. Malpica-Nieves
- Department of Biochemistry, Universidad Central del Caribe, Bayamón, PR 00956, USA
- Correspondence: (C.J.M.-N.); (S.N.S.); Tel.: +1-787-798-3001 (ext. 2057) (S.N.S.)
| | - Yomarie Rivera
- Department of Chiropractic, Universidad Central del Caribe, Bayamón, PR 00956, USA
| | | | - Colin G. Nichols
- Department of Cell Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Rüdiger W. Veh
- Institut für Zell- und Neurobiologie, Charité, 10115 Berlin, Germany
| | - Misty J. Eaton
- Department of Biochemistry, Universidad Central del Caribe, Bayamón, PR 00956, USA
| | - Serguei N. Skatchkov
- Department of Physiology, Universidad Central del Caribe, Bayamón, PR 00956, USA
- Department of Biochemistry, Universidad Central del Caribe, Bayamón, PR 00956, USA
- Correspondence: (C.J.M.-N.); (S.N.S.); Tel.: +1-787-798-3001 (ext. 2057) (S.N.S.)
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Zhao H, Wang M, Huang X, Wu X, Xiao H, Jin F, Lv J, Cheng J, Zhao Y, Zhang C. Wasp venom from Vespa magnifica acts as a neuroprotective agent to alleviate neuronal damage after stroke in rats. PHARMACEUTICAL BIOLOGY 2022; 60:334-346. [PMID: 35171059 PMCID: PMC8863380 DOI: 10.1080/13880209.2022.2032207] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 11/24/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
CONTEXT Acute ischaemic stroke (AIS) is a major cause of disability and death, which is a serious threat to human health and life. Wasp venom extracted from Vespa magnifica Smith (Vespidae) could treat major neurological disorders. OBJECTIVE This study investigated the effects of wasp venom on AIS in rats. MATERIAL AND METHODS We used a transient middle cerebral artery occlusion (MCAO) model in Sprague-Dawley rats (260-280 g, n = 8-15) with a sham operation group being treated as negative control. MCAO rats were treated with wasp venom (0.05, 0.2 and 0.6 mg/kg, i.p.) using intraperitoneal injection. After treatment 48 h, behavioural tests, cortical blood flow (CBF), TTC staining, H&E staining, Nissl staining, TUNEL assay, immunohistochemistry (IHC) and ELISA were employed to investigate neuroprotective effects of wasp venom. RESULTS Compared with the MCAO group, wasp venom (0.6 mg/kg) improved neurological impairment, accelerated CBF recovery (205.6 ± 52.92 versus 216.7 ± 34.56), reduced infarct volume (337.1 ± 113.2 versus 140.7 ± 98.03) as well as BBB permeability as evidenced by changes in claudin-5 and AQP4. In addition, function recovery of stroke by wasp venom treatment was associated with a decrease in TNF-α, IL-1β, IL-6 and inhibition activated microglia as well as apoptosis. Simultaneously, the wasp venom regulated the angiogenesis factors VEGF and b-FGF in the brain. CONCLUSIONS Wasp venom exhibited a potential neuroprotective effect for AIS. In the future, we will focus on determining whether the observed actions were due to a single compound or the interaction of multiple components of the venom.
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Affiliation(s)
- Hairong Zhao
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
- School of Medicine, Xiamen University, Xiamen, PR China
| | - Mei Wang
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
| | - Xi Huang
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
| | - Xiumei Wu
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
- National-Local Joint Engineering Research Center of Entomoceutics, Dali, PR China
| | - Huai Xiao
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
- National-Local Joint Engineering Research Center of Entomoceutics, Dali, PR China
| | - Fanmao Jin
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
| | - Jiaming Lv
- School of Medicine, Xiamen University, Xiamen, PR China
| | - Jidong Cheng
- School of Medicine, Xiamen University, Xiamen, PR China
| | - Yu Zhao
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
- National-Local Joint Engineering Research Center of Entomoceutics, Dali, PR China
| | - Chenggui Zhang
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, PR China
- National-Local Joint Engineering Research Center of Entomoceutics, Dali, PR China
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Aghighi Z, Ghorbani Z, Moghaddam MH, Fathi M, Abdollahifar MA, Soleimani M, Karimzadeh F, Rasoolijazi H, Aliaghaei A. Melittin ameliorates motor function and prevents autophagy-induced cell death and astrogliosis in rat models of cerebellar ataxia induced by 3-acetylpyridine. Neuropeptides 2022; 96:102295. [PMID: 36280441 DOI: 10.1016/j.npep.2022.102295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND Cerebellar ataxia (CA) is a form of ataxia that adversely affects the cerebellum. This study aims to investigate the therapeutic effects of melittin (MEL) on a 3-acetylpyridine-induced (3-AP) cerebellar ataxia (CA) rat model. METHODS Initially, CA rat models were generated by 3-AP administration followed by the subcutaneous injection of MEL. The open-field test was used for the evaluation of locomotion and anxiety. Immunohistochemistry was also conducted for the autophagy markers of LC3 and Beclin1. In the next step, the morphology of the astrocyte, the cell responsible for maintaining homeostasis in the CNS, was evaluated by the Sholl analysis. RESULTS The findings suggested that the administration of MEL in a 3-AP model of ataxia improved locomotion and anxiety (P < 0.001), decreased the expression of LC3 (P < 0.01) and Beclin1 (P < 0.05), increased astrocyte complexity (P < 0.05) and reduced astrocyte cell soma size (P < 0.001). CONCLUSIONS Overall, the findings imply that the MEL attenuates the 3-AP-induced autophagy, causes cell death and improves motor function. As such, it could be used as a therapeutic procedure for CA due to its neuroprotective effects.
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Affiliation(s)
- Zahra Aghighi
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Zeynab Ghorbani
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Meysam Hassani Moghaddam
- Department of Anatomical Sciences, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mobina Fathi
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad-Amin Abdollahifar
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mansoureh Soleimani
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fariba Karimzadeh
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Homa Rasoolijazi
- Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Abbas Aliaghaei
- Hearing Disorders Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Liu S, Wong HY, Xie L, Iqbal Z, Lei Z, Fu Z, Lam YY, Ramkrishnan AS, Li Y. Astrocytes in CA1 modulate schema establishment in the hippocampal-cortical neuron network. BMC Biol 2022; 20:250. [DOI: 10.1186/s12915-022-01445-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 10/20/2022] [Indexed: 11/11/2022] Open
Abstract
Abstract
Background
Schema, a concept from cognitive psychology used to explain how new information is integrated with previous experience, is a framework of acquired knowledge within associative network structures as biological correlate, which allows new relevant information to be quickly assimilated by parallel cortical encoding in the hippocampus (HPC) and cortex. Previous work demonstrated that myelin generation in the anterior cingulate cortex (ACC) plays a critical role for dynamic paired association (PA) learning and consolidation, while astrocytes in ACC play a vital role in cognitive decision-making. However, circuit components and mechanism involving HPC-anterior cingulate cortex (ACC) during schema formation remain uncertain. Moreover, the correlation between HPC-ACC circuit and HPC astrocytic activity is unclear.
Results
Utilizing a paired association (PA) behavioral paradigm, we dynamically recorded calcium signals of CA1-ACC projection neurons and ACC neurons during schema formation. Depending on the characteristics of the calcium signals, three distinct stages of schema establishment process were identified. The recruitment of CA1-ACC network was investigated in each stage under CA1 astrocytes Gi pathway chemogenetic activation. Results showed that CA1-ACC projecting neurons excitation gradually decreased along with schema development, while ACC neurons revealed an excitation peak in the middle stage. CA1 astrocytic Gi pathway activation will disrupt memory schema development by reducing CA1-ACC projection neuron recruitment in the initial stage and prevent both CA1-ACC projection neurons and ACC neuron excitation in the middle stage. CA1 astrocytes Gi markedly suppress new PA assimilation into the established memory schema.
Conclusions
These results not only reveal the dynamic feature of CA1-ACC network during schema establishment, but also suggest CA1 astrocyte contribution in different stages of schema establishment.
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Ismail FS, Faustmann PM, Kümmel ML, Förster E, Faustmann TJ, Corvace F. Brivaracetam exhibits mild pro-inflammatory features in an in vitro astrocyte-microglia co-culture model of inflammation. Front Cell Neurosci 2022; 16:995861. [DOI: 10.3389/fncel.2022.995861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022] Open
Abstract
Implications of glia in the pathophysiology of epilepsy raise the question of how these cells besides neurons are responsive to antiseizure medications (ASMs). Understanding ASM effects on glia and glia-mediated inflammation may help to explore astrocytes and microglia as potential targets for alternative anti-epileptogenic therapies. The aim of this study was to investigate the effects of the new generation ASM brivaracetam (BRV) in an astrocyte-microglia co-culture model of inflammation. Primary rat astrocytes co-cultures containing 5%–10% (M5, “physiological” conditions) or 30%–40% (M30, “pathological inflammatory” conditions) of microglia were treated with different concentrations of BRV (0.5, 2, 10, and 20 μg/ml) for 24 h. Glial cell viability was measured by MTT assay. Microglial activation states were analyzed by immunocytochemistry and astroglial connexin 43 (Cx43) expression by Western blot analysis and immunocytochemistry. Gap-junctional coupling was studied via Scrape Loading. Incubation with high, overdose concentration (20 μg/ml) of BRV significantly reduced the glial cell viability under physiological conditions (p < 0.01: **). Treatment with BRV in therapeutic concentrations (0.5 and 2 μg/ml) reduced the resting microglia (p < 0.05: *) and increased the microglial activation under inflammatory conditions (p < 0.01: **). Astroglial Cx43 expression was not affected. The gap-junctional coupling significantly increased only by 0.5 μg/ml BRV under physiological conditions (p < 0.05: *). Our findings suggest mild pro-inflammatory, in vitro features of BRV with regard to microglia morphology. BRV showed no effects on Cx43 expression and only limited effects on gap-junctional coupling. Reduction of glial viability by overdose BRV indicates possible toxic effects.
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Li J, Feng P, Zhao L, Chen J, Du M, Song J, Wu Y. Transition behavior of the seizure dynamics modulated by the astrocyte inositol triphosphate noise. CHAOS (WOODBURY, N.Y.) 2022; 32:113121. [PMID: 36456345 DOI: 10.1063/5.0124123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 10/17/2022] [Indexed: 06/17/2023]
Abstract
Epilepsy is a neurological disorder with recurrent seizures, which convey complex dynamical characteristics including chaos and randomness. Until now, the underlying mechanism has not been fully elucidated, especially the bistable property beneath the epileptic random induction phenomena in certain conditions. Inspired by the recent finding that astrocyte GTPase-activating protein (G-protein)-coupled receptors could be involved in stochastic epileptic seizures, we proposed a neuron-astrocyte network model, incorporating the noise of the astrocytic second messenger, inositol triphosphate (IP3) that is modulated by G-protein-coupled receptor activation. Based on this model, we have statistically analyzed the transitions of epileptic seizures by performing repeatable simulation trials. Our simulation results show that the increase in the IP3 noise intensity induces depolarization-block epileptic seizures together with an increase in neuronal firing frequency, consistent with corresponding experiments. Meanwhile, the bistable states of the seizure dynamics were present under certain noise intensities, during which the neuronal firing pattern switches between regular sparse spiking and epileptic seizure states. This random presence of epileptic seizures is absent when the noise intensity continues to increase, accompanying with an increase in the epileptic depolarization block duration. The simulation results also shed light on the fact that calcium signals in astrocytes play significant roles in the pattern formations of the epileptic seizure. Our results provide a potential pathway for understanding the epileptic randomness in certain conditions.
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Affiliation(s)
- Jiajia Li
- College of Information and Control Engineering, Xi'an University of Architecture and Technology, Shaanxi, Xi'an 710055, China
| | - Peihua Feng
- State Key Laboratory for Strength and Vibration of Mechanical Structures, National Demonstration Center for Experimental Mechanics Education, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Liang Zhao
- College of Information and Control Engineering, Xi'an University of Architecture and Technology, Shaanxi, Xi'an 710055, China
| | - Junying Chen
- College of Information and Control Engineering, Xi'an University of Architecture and Technology, Shaanxi, Xi'an 710055, China
| | - Mengmeng Du
- School of Mathematics and Data Science, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Jian Song
- Department of Neurosurgery, Wuhan General Hospital of PLA, Wuhan 430070, China
| | - Ying Wu
- State Key Laboratory for Strength and Vibration of Mechanical Structures, National Demonstration Center for Experimental Mechanics Education, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China
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Yu F, Yan L, Sun J, Zhao Y, Yuan Y, Gu J, Bian J, Zou H, Liu Z. Gap junction intercellular communication mediates cadmium-induced apoptosis in hepatocytes via the Fas/FasL pathway. ENVIRONMENTAL TOXICOLOGY 2022; 37:2692-2702. [PMID: 35920667 DOI: 10.1002/tox.23629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
As a common environmental pollutant, cadmium (Cd) causes damage to many organs of the body. Gap junction intercellular communication (GJIC) represents one of the most important routes of rapid signaling between cells. However, the mechanisms underlying GJIC's role in hepatotoxicity induced by Cd remain unknown. We established a Cd poisoning model in vitro by co-culturing Cd-exposed and unexposed hepatocytes and found that 18β-glycyrrhetinic acid (GA), a GJIC inhibitor, can effectively reduce the apoptosis rate of healthy cells co-cultured with apoptotic cells treated with Cd. We also found that anti-FasL antibody had the same effect. However, in mono-cultured cells, GA treatment in combination with Cd was found to aggravate the damage induced by Cd exposure, increase the level of oxidative stress and protein expression of HO-1, decrease the mitochondrial membrane potential, incur more serious morphological damage to mitochondria than Cd treatment alone. Moreover, compared with Cd-only exposure, GA and Cd co-treatment further increased the expression levels of the apoptosis-related proteins Fas, FasL, FADD and the ratio of Bax/Bcl-2, inhibited the protein expression of ASK1 and Daxx. We also found that the protein expression of Daxx in siFADD + Cd hepatocytes was significantly higher than in Cd-treated cells. Thus, our study suggests that gap junction inhibition may play a dual role in Cd-induced cell damage by inhibiting the transmission of death signals from damaged cells to healthy cells but also aggravating the transmission of death signals between damaged cells, and that the Fas/FasL-mediated death receptor pathway may play an important role in this process.
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Affiliation(s)
- Fan Yu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Lianqi Yan
- Department of Orthopedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, People's Republic of China
- Department of Orthopedics, Clinical Medical College of Yangzhou University, Subei People's Hospital, Yangzhou, Jiangsu, People's Republic of China
| | - Jian Sun
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Yumeng Zhao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Yan Yuan
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Jianhong Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Jianchun Bian
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Hui Zou
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Zongping Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
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Portal B, Vasile F, Zapata J, Lejards C, Ait Tayeb AEK, Colle R, Verstuyft C, Corruble E, Rouach N, Guiard BP. Astroglial Connexins Inactivation Increases Relapse of Depressive-like Phenotype after Antidepressant Withdrawal. Int J Mol Sci 2022; 23:13227. [PMID: 36362016 PMCID: PMC9656718 DOI: 10.3390/ijms232113227] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 09/11/2023] Open
Abstract
Studies suggest that astrocytic connexins (Cx) have an important role in the regulation of high brain functions through their ability to establish fine-tuned communication with neurons within the tripartite synapse. In light of these properties, growing evidence suggests a role of Cx in psychiatric disorders such as major depression but also in the therapeutic activity of antidepressant drugs. However, the real impact of Cx on treatment response and the underlying neurobiological mechanisms remain yet to be clarified. On this ground, the present study was designed to evaluate the functional activity of Cx in a mouse model of depression based on chronic corticosterone exposure and to determine to which extent their pharmacological inactivation influences the antidepressant-like activity of venlafaxine (VENLA). On the one hand, our results indicate that depressed mice have impaired Cx-based gap-junction and hemichannel activities. On the other hand, while VENLA exerts robust antidepressant-like activity in depressed mice; this effect is abolished by the pharmacological inhibition of Cx with carbenoxolone (CBX). Interestingly, the combination of VENLA and CBX is also associated with a higher rate of relapse after treatment withdrawal. To our knowledge, this study is one of the first to develop a model of relapse, and our results reveal that Cx-mediated dynamic neuroglial interactions play a critical role in the efficacy of monoaminergic antidepressant drugs, thus providing new targets for the treatment of depression.
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Affiliation(s)
- Benjamin Portal
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Flora Vasile
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Jonathan Zapata
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Camille Lejards
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Abd El Kader Ait Tayeb
- CESP, MOODS Team, INSERM, Faculté de Médecine, University of Paris-Saclay, 94275 Le Kremlin Bicêtre, France
- Service Hospitalo-Universitaire de Psychiatrie de Bicêtre, Hôpitaux Universitaires Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Hôpital de Bicêtre, 94275 Le Kremlin Bicêtre, France
| | - Romain Colle
- CESP, MOODS Team, INSERM, Faculté de Médecine, University of Paris-Saclay, 94275 Le Kremlin Bicêtre, France
- Service Hospitalo-Universitaire de Psychiatrie de Bicêtre, Hôpitaux Universitaires Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Hôpital de Bicêtre, 94275 Le Kremlin Bicêtre, France
| | - Céline Verstuyft
- CESP, MOODS Team, INSERM, Faculté de Médecine, University of Paris-Saclay, 94275 Le Kremlin Bicêtre, France
- Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie de Bicêtre, Hôpitaux Universitaires Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Hôpital de Bicêtre, 94275 Le Kremlin Bicêtre, France
| | - Emmanuelle Corruble
- CESP, MOODS Team, INSERM, Faculté de Médecine, University of Paris-Saclay, 94275 Le Kremlin Bicêtre, France
- Service Hospitalo-Universitaire de Psychiatrie de Bicêtre, Hôpitaux Universitaires Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Hôpital de Bicêtre, 94275 Le Kremlin Bicêtre, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Bruno P. Guiard
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, 31062 Toulouse, France
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Kaleem M, Dalhat MH, Azmi L, Asar TO, Ahmad W, Alghanmi M, Almostadi A, Zughaibi TA, Tabrez S. An Insight into Molecular Targets of Breast Cancer Brain Metastasis. Int J Mol Sci 2022; 23:ijms231911687. [PMID: 36232989 PMCID: PMC9569595 DOI: 10.3390/ijms231911687] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
Brain metastasis is one of the major reasons of death in breast cancer (BC) patients, significantly affecting the quality of life, physical activity, and interdependence on several individuals. There is no clear evidence in scientific literature that depicts an exact mechanism relating to brain metastasis in BC patients. The tendency to develop breast cancer brain metastases (BCBMs) differs by the BC subtype, varying from almost half with triple-negative breast cancer (TNBC) (HER2- ER- PR-), one-third with HER2+ (human epidermal growth factor receptor 2-positive, and around one-tenth with luminal subclass (ER+ (estrogen positive) or PR+ (progesterone positive)) breast cancer. This review focuses on the molecular pathways as possible therapeutic targets of BCBMs and their potent drugs under different stages of clinical trial. In view of increased numbers of clinical trials and systemic studies, the scientific community is hopeful of unraveling the underlying mechanisms of BCBMs that will help in designing an effective treatment regimen with multiple molecular targets.
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Affiliation(s)
- Mohammed Kaleem
- Department of Pharmacology, Faculty of Pharmacy, Dadasaheb Balpande College of Pharmacy, Nagpur 440037, India
| | - Mahmood Hassan Dalhat
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Lubna Azmi
- Department of Pharmaceutics and Pharmacokinetics, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Turky Omar Asar
- Department of Biology, College of Science and Arts at Alkamil, University of Jeddah, Jeddah 23218, Saudi Arabia
| | - Wasim Ahmad
- Department of Kuliyate Tib, National Institute of Unani Medicine, Kottigepalya, Bengaluru 560091, India
| | - Maimonah Alghanmi
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Amal Almostadi
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Torki A. Zughaibi
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Shams Tabrez
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Correspondence:
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An interplay between cellular growth and atypical fusion defines morphogenesis of a modular glial niche in Drosophila. Nat Commun 2022; 13:4999. [PMID: 36008397 PMCID: PMC9411534 DOI: 10.1038/s41467-022-32685-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 08/10/2022] [Indexed: 11/16/2022] Open
Abstract
Neural stem cells (NSCs) live in an intricate cellular microenvironment supporting their activity, the niche. Whilst shape and function are inseparable, the morphogenetic aspects of niche development are poorly understood. Here, we use the formation of a glial niche to investigate acquisition of architectural complexity. Cortex glia (CG) in Drosophila regulate neurogenesis and build a reticular structure around NSCs. We first show that individual CG cells grow tremendously to ensheath several NSC lineages, employing elaborate proliferative mechanisms which convert these cells into syncytia rich in cytoplasmic bridges. CG syncytia further undergo homotypic cell–cell fusion, using defined cell surface receptors and actin regulators. Cellular exchange is however dynamic in space and time. This atypical cell fusion remodels cellular borders, restructuring the CG syncytia. Ultimately, combined growth and fusion builds the multi-level architecture of the niche, and creates a modular, spatial partition of the NSC population. Our findings provide insights into how a niche forms and organises while developing intimate contacts with a stem cell population. Little is known of how the architectural complexity of the neural stem cell niche is achieved. Rujano et al. show that the morphogenesis of a glial niche in Drosophila involves complex proliferative strategies and atypical cell–cell fusion.
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Connexins Signatures of the Neurovascular Unit and Their Physio-Pathological Functions. Int J Mol Sci 2022; 23:ijms23179510. [PMID: 36076908 PMCID: PMC9455936 DOI: 10.3390/ijms23179510] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
Central nervous system (CNS) homeostasis is closely linked to the delicate balance of the microenvironment in which different cellular components of the neurovascular unit (NVU) coexist. Intercellular communication plays a pivotal role in exchanges of signaling molecules and mediators essential for survival functions, as well as in the removal of disturbing elements that can lead to related pathologies. The specific signatures of connexins (Cxs), proteins which form either gap junctions (GJs) or hemichannels (HCs), represent the biological substrate of the pathophysiological balance. Connexin 43 (Cx43) is undoubtedly one of the most important factors in glia–neuro–vascular crosstalk. Herein, Cxs signatures of every NVU component are highlighted and their critical influence on functional processes in healthy and pathological conditions of nervous microenvironment is reviewed.
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