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Zhao Y, Liu K, Wang Y, Ma Y, Guo W, Shi C. Human-mouse chimeric brain models constructed from iPSC-derived brain cells: Applications and challenges. Exp Neurol 2024; 379:114848. [PMID: 38857749 DOI: 10.1016/j.expneurol.2024.114848] [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: 03/08/2024] [Revised: 05/27/2024] [Accepted: 06/06/2024] [Indexed: 06/12/2024]
Abstract
The establishment of reliable human brain models is pivotal for elucidating specific disease mechanisms and facilitating the discovery of novel therapeutic strategies for human brain disorders. Human induced pluripotent stem cell (iPSC) exhibit remarkable self-renewal capabilities and can differentiate into specialized cell types. This makes them a valuable cell source for xenogeneic or allogeneic transplantation. Human-mouse chimeric brain models constructed from iPSC-derived brain cells have emerged as valuable tools for modeling human brain diseases and exploring potential therapeutic strategies for brain disorders. Moreover, the integration and functionality of grafted stem cells has been effectively assessed using these models. Therefore, this review provides a comprehensive overview of recent progress in differentiating human iPSC into various highly specialized types of brain cells. This review evaluates the characteristics and functions of the human-mouse chimeric brain model. We highlight its potential roles in brain function and its ability to reconstruct neural circuitry in vivo. Additionally, we elucidate factors that influence the integration and differentiation of human iPSC-derived brain cells in vivo. This review further sought to provide suitable research models for cell transplantation therapy. These research models provide new insights into neuropsychiatric disorders, infectious diseases, and brain injuries, thereby advancing related clinical and academic research.
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Affiliation(s)
- Ya Zhao
- Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Ke Liu
- Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China; Gansu University of traditional Chinese medicine, Lanzhou 730030, PR China
| | - Yinghua Wang
- Medical College of Yan'an University, Yan'an 716000, PR China
| | - Yifan Ma
- Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China; Gansu University of traditional Chinese medicine, Lanzhou 730030, PR China
| | - Wenwen Guo
- Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Changhong Shi
- Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China.
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Ifediora N, Canoll P, Hargus G. Human stem cell transplantation models of Alzheimer's disease. Front Aging Neurosci 2024; 16:1354164. [PMID: 38450383 PMCID: PMC10915253 DOI: 10.3389/fnagi.2024.1354164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 02/06/2024] [Indexed: 03/08/2024] Open
Abstract
Alzheimer's disease (AD) is the most frequent form of dementia. It is characterized by pronounced neuronal degeneration with formation of neurofibrillary tangles and deposition of amyloid β throughout the central nervous system. Animal models have provided important insights into the pathogenesis of AD and they have shown that different brain cell types including neurons, astrocytes and microglia have important functions in the pathogenesis of AD. However, there are difficulties in translating promising therapeutic observations in mice into clinical application in patients. Alternative models using human cells such as human induced pluripotent stem cells (iPSCs) may provide significant advantages, since they have successfully been used to model disease mechanisms in neurons and in glial cells in neurodegenerative diseases in vitro and in vivo. In this review, we summarize recent studies that describe the transplantation of human iPSC-derived neurons, astrocytes and microglial cells into the forebrain of mice to generate chimeric transplantation models of AD. We also discuss opportunities, challenges and limitations in using differentiated human iPSCs for in vivo disease modeling and their application for biomedical research.
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Affiliation(s)
- Nkechime Ifediora
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
| | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
| | - Gunnar Hargus
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, United States
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Saito K, Shigetomi E, Shinozaki Y, Kobayashi K, Parajuli B, Kubota Y, Sakai K, Miyakawa M, Horiuchi H, Nabekura J, Koizumi S. Microglia sense astrocyte dysfunction and prevent disease progression in an Alexander disease model. Brain 2024; 147:698-716. [PMID: 37955589 PMCID: PMC10834242 DOI: 10.1093/brain/awad358] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 09/28/2023] [Accepted: 10/06/2023] [Indexed: 11/14/2023] Open
Abstract
Alexander disease (AxD) is an intractable neurodegenerative disorder caused by GFAP mutations. It is a primary astrocyte disease with a pathological hallmark of Rosenthal fibres within astrocytes. AxD astrocytes show several abnormal phenotypes. Our previous study showed that AxD astrocytes in model mice exhibit aberrant Ca2+ signals that induce AxD aetiology. Here, we show that microglia have unique phenotypes with morphological and functional alterations, which are related to the pathogenesis of AxD. Immunohistochemical studies of 60TM mice (AxD model) showed that AxD microglia exhibited highly ramified morphology. Functional changes in microglia were assessed by Ca2+ imaging using hippocampal brain slices from Iba1-GCaMP6-60TM mice and two-photon microscopy. We found that AxD microglia showed aberrant Ca2+ signals, with high frequency Ca2+ signals in both the processes and cell bodies. These microglial Ca2+ signals were inhibited by pharmacological blockade or genetic knockdown of P2Y12 receptors but not by tetrodotoxin, indicating that these signals are independent of neuronal activity but dependent on extracellular ATP from non-neuronal cells. Our single-cell RNA sequencing data showed that the expression level of Entpd2, an astrocyte-specific gene encoding the ATP-degrading enzyme NTPDase2, was lower in AxD astrocytes than in wild-type astrocytes. In situ ATP imaging using the adeno-associated virus vector GfaABC1D ATP1.0 showed that exogenously applied ATP was present longer in 60TM mice than in wild-type mice. Thus, the increased ATP level caused by the decrease in its metabolizing enzyme in astrocytes could be responsible for the enhancement of microglial Ca2+ signals. To determine whether these P2Y12 receptor-mediated Ca2+ signals in AxD microglia play a significant role in the pathological mechanism, a P2Y12 receptor antagonist, clopidogrel, was administered. Clopidogrel significantly exacerbated pathological markers in AxD model mice and attenuated the morphological features of microglia, suggesting that microglia play a protective role against AxD pathology via P2Y12 receptors. Taken together, we demonstrated that microglia sense AxD astrocyte dysfunction via P2Y12 receptors as an increase in extracellular ATP and alter their morphology and Ca2+ signalling, thereby protecting against AxD pathology. Although AxD is a primary astrocyte disease, our study may facilitate understanding of the role of microglia as a disease modifier, which may contribute to the clinical diversity of AxD.
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Affiliation(s)
- Kozo Saito
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Youichi Shinozaki
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Kenji Kobayashi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Bijay Parajuli
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Yuto Kubota
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Kent Sakai
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Miho Miyakawa
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Hiroshi Horiuchi
- Division of Homeostatic Development, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Aichi 444-8585, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Aichi 444-8585, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
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Shinozaki Y, Namekata K, Guo X, Harada T. Glial cells as a promising therapeutic target of glaucoma: beyond the IOP. FRONTIERS IN OPHTHALMOLOGY 2024; 3:1310226. [PMID: 38983026 PMCID: PMC11182302 DOI: 10.3389/fopht.2023.1310226] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/18/2023] [Indexed: 07/11/2024]
Abstract
Glial cells, a type of non-neuronal cell found in the central nervous system (CNS), play a critical role in maintaining homeostasis and regulating CNS functions. Recent advancements in technology have paved the way for new therapeutic strategies in the fight against glaucoma. While intraocular pressure (IOP) is the most well-known modifiable risk factor, a significant number of glaucoma patients have normal IOP levels. Because glaucoma is a complex, multifactorial disease influenced by various factors that contribute to its onset and progression, it is imperative that we consider factors beyond IOP to effectively prevent or slow down the disease's advancement. In the realm of CNS neurodegenerative diseases, glial cells have emerged as key players due to their pivotal roles in initiating and hastening disease progression. The inhibition of dysregulated glial function holds the potential to protect neurons and restore brain function. Consequently, glial cells represent an enticing therapeutic candidate for glaucoma, even though the majority of glaucoma research has historically concentrated solely on retinal ganglion cells (RGCs). In addition to the neuroprotection of RGCs, the proper regulation of glial cell function can also facilitate structural and functional recovery in the retina. In this review, we offer an overview of recent advancements in understanding the non-cell-autonomous mechanisms underlying the pathogenesis of glaucoma. Furthermore, state-of-the-art technologies have opened up possibilities for regenerating the optic nerve, which was previously believed to be incapable of regeneration. We will also delve into the potential roles of glial cells in the regeneration of the optic nerve and the restoration of visual function.
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Affiliation(s)
- Youichi Shinozaki
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Parajuli B, Koizumi S. Strategies for Manipulating Microglia to Determine Their Role in the Healthy and Diseased Brain. Neurochem Res 2023; 48:1066-1076. [PMID: 36085395 PMCID: PMC9462627 DOI: 10.1007/s11064-022-03742-6] [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: 08/08/2022] [Revised: 08/08/2022] [Accepted: 08/29/2022] [Indexed: 11/30/2022]
Abstract
Microglia are the specialized macrophages of the central nervous system and play an important role in neural circuit development, modulating neurotransmission, and maintaining brain homeostasis. Microglia in normal brain is quiescent and show ramified morphology with numerous branching processes. They constantly survey their surrounding microenvironment through the extension and retraction of their processes and interact with neurons, astrocytes, and blood vessels using these processes. Microglia respond quickly to any pathological event in the brain by assuming ameboid morphology devoid of branching processes and restore homeostasis. However, when there is chronic inflammation, microglia may lose their homeostatic functions and secrete various proinflammatory cytokines and mediators that initiate neural dysfunction and neurodegeneration. In this article, we review the role of microglia in the normal brain and in various pathological brain conditions, such as Alzheimer's disease and multiple sclerosis. We describe strategies to manipulate microglia, focusing on depletion, repopulation, and replacement, and we discuss their therapeutic potential.
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Affiliation(s)
- Bijay Parajuli
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
- GLIA Center, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan.
- GLIA Center, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan.
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Qiao C, Liu Z, Qie S. The Implications of Microglial Regulation in Neuroplasticity-Dependent Stroke Recovery. Biomolecules 2023; 13:biom13030571. [PMID: 36979506 PMCID: PMC10046452 DOI: 10.3390/biom13030571] [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: 01/17/2023] [Revised: 02/23/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
Stroke causes varying degrees of neurological deficits, leading to corresponding dysfunctions. There are different therapeutic principles for each stage of pathological development. Neuroprotection is the main treatment in the acute phase, and functional recovery becomes primary in the subacute and chronic phases. Neuroplasticity is considered the basis of functional restoration and neurological rehabilitation after stroke, including the remodeling of dendrites and dendritic spines, axonal sprouting, myelin regeneration, synapse shaping, and neurogenesis. Spatiotemporal development affects the spontaneous rewiring of neural circuits and brain networks. Microglia are resident immune cells in the brain that contribute to homeostasis under physiological conditions. Microglia are activated immediately after stroke, and phenotypic polarization changes and phagocytic function are crucial for regulating focal and global brain inflammation and neurological recovery. We have previously shown that the development of neuroplasticity is spatiotemporally consistent with microglial activation, suggesting that microglia may have a profound impact on neuroplasticity after stroke and may be a key therapeutic target for post-stroke rehabilitation. In this review, we explore the impact of neuroplasticity on post-stroke restoration as well as the functions and mechanisms of microglial activation, polarization, and phagocytosis. This is followed by a summary of microglia-targeted rehabilitative interventions that influence neuroplasticity and promote stroke recovery.
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Affiliation(s)
- Chenye Qiao
- Department of Rehabilitation, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Zongjian Liu
- Department of Rehabilitation, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Shuyan Qie
- Department of Rehabilitation, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
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Cuní-López C, Stewart R, White AR, Quek H. 3D in vitro modelling of human patient microglia: A focus on clinical translation and drug development in neurodegenerative diseases. J Neuroimmunol 2023; 375:578017. [PMID: 36657374 DOI: 10.1016/j.jneuroim.2023.578017] [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: 11/03/2022] [Revised: 12/28/2022] [Accepted: 01/08/2023] [Indexed: 01/13/2023]
Abstract
Microglia have an increasingly well-recognised role in the pathogenesis of neurodegenerative diseases, thereby becoming attractive therapeutic targets. However, the development of microglia-targeted therapeutics for neurodegeneration has had limited success. This stems partly from the lack of clinically relevant microglia model systems. To circumvent this translational gap, patient-derived microglial cell models established using conventional 2D in vitro techniques have emerged. Though promising, these models lack the microenvironment and multicellular interactions of the brain needed to maintain microglial homeostasis. In this review, we discuss the use of 3D in vitro platforms to improve microglia modelling and their potential benefits to fast-track drug development for neurodegenerative diseases.
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Affiliation(s)
- Carla Cuní-López
- Mental Health and Neuroscience, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; Faculty of Medicine, The University of Queensland, Brisbane 4006, QLD, Australia.
| | - Romal Stewart
- Mental Health and Neuroscience, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; UQ Centre for Clinical Research, The University of Queensland, Brisbane 4006, QLD, Australia.
| | - Anthony R White
- Mental Health and Neuroscience, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; School of Biomedical Science, The University of Queensland, Brisbane 4072, QLD, Australia.
| | - Hazel Quek
- Mental Health and Neuroscience, QIMR Berghofer Medical Research Institute, Brisbane 4006, QLD, Australia; School of Biomedical Science, The University of Queensland, Brisbane 4072, QLD, Australia; School of Biomedical Science, Queensland University of Technology, Brisbane 4059, QLD, Australia.
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8
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Advanced therapeutic strategies targeting microglia: beyond neuroinflammation. Arch Pharm Res 2022; 45:618-630. [PMID: 36166145 DOI: 10.1007/s12272-022-01406-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 09/19/2022] [Indexed: 11/02/2022]
Abstract
For a long time, microglia have been recognized as the main culprits of neuroinflammatory responses because they are primary phagocytes present in the parenchyma of the central nervous system (CNS). However, with the evolving concept of microglial biology, advanced and precise approaches, rather than the global inhibition of activated microglia, have been proposed in the management of neurological disorders. Yolk sac-derived resident microglia have heterogeneous composition according to brain region, sex, and diseases. They play a key role in the maintenance of CNS homeostasis and as primary phagocytes. The perturbation of microglia development can induce neurodevelopmental disorders. Microglia aggravate or alleviate neuroinflammation according to microenvironment and their spatiotemporal dynamics. They are long-lived cells and repopulate via their proliferation or external monocyte engraft. Based on this evolving concept, understanding advanced therapeutic strategies targeting microglia can give us an opportunity to discover novel therapies for neurological disorders.
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Ogaki A, Ikegaya Y, Koyama R. Replacement of Mouse Microglia With Human Induced Pluripotent Stem Cell (hiPSC)-Derived Microglia in Mouse Organotypic Slice Cultures. Front Cell Neurosci 2022; 16:918442. [PMID: 35910250 PMCID: PMC9325970 DOI: 10.3389/fncel.2022.918442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022] Open
Abstract
Microglia, the major immune cells in the brain, are reported to differ in gene expression patterns among species. Therefore, it would be preferable in some cases to use human microglia rather than mouse microglia in microglia-targeted disease research. In the past half a decade, researchers have developed in vivo transplantation methods in which human induced pluripotent stem cell-derived microglia (hiPSC-MG) are transplanted into a living mouse brain. However, in vivo transplantation methods are not necessarily accessible to all researchers due to the difficulty of obtaining the materials needed and the transplantation technique itself. In addition, for in vivo systems for microglia-targeted drug screening, it is difficult to control the pharmacokinetics, especially blood-brain barrier permeability. Therefore, in addition to existing in vivo transplantation systems, the development of an ex vivo transplantation system would help to further evaluate the properties of hiPSC-MG. In this study, we aimed to establish a method to efficiently transplant hiPSC-MG into cultured mouse hippocampal slices. We found that approximately 80% of the total microglia in a cultured slice were replaced by hiPSC-derived microglia when innate microglia were pharmacologically removed prior to transplantation. Furthermore, when neuronal death was induced by applying Kainic acid (KA) to slice cultures, transplanted hiPSC-MG changed their morphology and phagocytosed cell debris. Thus, this study provides a method to transplant hiPSC-MG into the mouse hippocampal slice cultures with a high replacement rate. Because the transplanted microglia survived and exerted phagocytic functions, this method will be useful for evaluating the properties of hiPSC-MG ex vivo.
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Affiliation(s)
- Ari Ogaki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- *Correspondence: Ryuta Koyama
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Var SR, Shetty AV, Grande AW, Low WC, Cheeran MC. Microglia and Macrophages in Neuroprotection, Neurogenesis, and Emerging Therapies for Stroke. Cells 2021; 10:3555. [PMID: 34944064 PMCID: PMC8700390 DOI: 10.3390/cells10123555] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/20/2022] Open
Abstract
Stroke remains the number one cause of morbidity in the United States. Within weeks to months after an ischemic event, there is a resolution of inflammation and evidence of neurogenesis; however, years following a stroke, there is evidence of chronic inflammation in the central nervous system, possibly by the persistence of an autoimmune response to brain antigens as a result of ischemia. The mechanisms underlying the involvement of macrophage and microglial activation after stroke are widely acknowledged as having a role in ischemic stroke pathology; thus, modulating inflammation and neurological recovery is a hopeful strategy for treating the long-term outcomes after ischemic injury. Current treatments fail to provide neuroprotective or neurorestorative benefits after stroke; therefore, to ameliorate brain injury-induced deficits, therapies must alter both the initial response to injury and the subsequent inflammatory process. This review will address differences in macrophage and microglia nomenclature and summarize recent work in elucidating the mechanisms of macrophage and microglial participation in antigen presentation, neuroprotection, angiogenesis, neurogenesis, synaptic remodeling, and immune modulating strategies for treating the long-term outcomes after ischemic injury.
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Affiliation(s)
- Susanna R. Var
- Department of Neurosurgery, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (S.R.V.); (A.W.G.)
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN 55108, USA
- Stem Cell Institute, University of Minnesota Medical School, Minneapolis, MN 55455, USA;
| | - Anala V. Shetty
- Stem Cell Institute, University of Minnesota Medical School, Minneapolis, MN 55455, USA;
- Department of Biological Sciences, University of Minnesota Medical School, Minneapolis, MN 55108, USA
| | - Andrew W. Grande
- Department of Neurosurgery, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (S.R.V.); (A.W.G.)
- Stem Cell Institute, University of Minnesota Medical School, Minneapolis, MN 55455, USA;
| | - Walter C. Low
- Department of Neurosurgery, University of Minnesota Medical School, Minneapolis, MN 55455, USA; (S.R.V.); (A.W.G.)
- Stem Cell Institute, University of Minnesota Medical School, Minneapolis, MN 55455, USA;
| | - Maxim C. Cheeran
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN 55108, USA
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