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Li H, Watkins LR, Wang X. Microglia in neuroimmunopharmacology and drug addiction. Mol Psychiatry 2024:10.1038/s41380-024-02443-6. [PMID: 38302560 DOI: 10.1038/s41380-024-02443-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/03/2024]
Abstract
Drug addiction is a chronic and debilitating disease that is considered a global health problem. Various cell types in the brain are involved in the progression of drug addiction. Recently, the xenobiotic hypothesis has been proposed, which frames substances of abuse as exogenous molecules that are responded to by the immune system as foreign "invaders", thus triggering protective inflammatory responses. An emerging body of literature reveals that microglia, the primary resident immune cells in the brain, play an important role in the progression of addiction. Repeated cycles of drug administration cause a progressive, persistent induction of neuroinflammation by releasing microglial proinflammatory cytokines and their metabolic products. This contributes to drug addiction via modulation of neuronal function. In this review, we focus on the role of microglia in the etiology of drug addiction. Then, we discuss the dynamic states of microglia and the correlative and causal evidence linking microglia to drug addiction. Finally, possible mechanisms of how microglia sense drug-related stimuli and modulate the addiction state and how microglia-targeted anti-inflammation therapies affect addiction are reviewed. Understanding the role of microglia in drug addiction may help develop new treatment strategies to fight this devastating societal challenge.
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Affiliation(s)
- Hongyuan Li
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China
| | - Linda R Watkins
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Xiaohui Wang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
- School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, 230026, China.
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China.
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2
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He Y, Liu T, He Q, Ke W, Li X, Du J, Deng S, Shu Z, Wu J, Yang B, Wang Y, Mao Y, Rao Y, Shu Y, Peng B. Microglia facilitate and stabilize the response to general anesthesia via modulating the neuronal network in a brain region-specific manner. eLife 2023; 12:RP92252. [PMID: 38131301 PMCID: PMC10746144 DOI: 10.7554/elife.92252] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023] Open
Abstract
General anesthesia leads to a loss of consciousness and an unrousable state in patients. Although general anesthetics are widely used in clinical practice, their underlying mechanisms remain elusive. The potential involvement of nonneuronal cells is unknown. Microglia are important immune cells in the central nervous system (CNS) that play critical roles in CNS function and dysfunction. We unintentionally observed delayed anesthesia induction and early anesthesia emergence in microglia-depleted mice. We found that microglial depletion differentially regulates neuronal activities by suppressing the neuronal network of anesthesia-activated brain regions and activating emergence-activated brain regions. Thus, microglia facilitate and stabilize the anesthesia status. This influence is not mediated by dendritic spine plasticity. Instead, it relies on the activation of microglial P2Y12 and subsequent calcium influx, which facilitates the general anesthesia response. Together, we elucidate the regulatory role of microglia in general anesthesia, extending our knowledge of how nonneuronal cells modulate neuronal activities.
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Affiliation(s)
- Yang He
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Taohui Liu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Quansheng He
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Wei Ke
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Xiaoyu Li
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Jinjin Du
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Suixin Deng
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Zhenfeng Shu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Jialin Wu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Baozhi Yang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Yuqing Wang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- School of Basic Medical Sciences, Jinzhou Medical UniversityJinzhouChina
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Yanxia Rao
- Department of Neurology, Zhongshan Hospital, Department of Laboratory Animal Science, MOE Frontiers Center for Brain Science, Fudan UniversityShanghaiChina
| | - Yousheng Shu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
| | - Bo Peng
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, MOE Innovative Center for New Drug Development of Immune Inflammatory Diseases, Fudan UniversityShanghaiChina
- Co-Innovation Center of Neurodegeneration, Nantong UniversityNantongChina
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3
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Ralvenius WT, Mungenast AE, Woolf H, Huston MM, Gillingham TZ, Godin SK, Penney J, Cam HP, Gao F, Fernandez CG, Czako B, Lightfoot Y, Ray WJ, Beckmann A, Goate AM, Marcora E, Romero-Molina C, Ayata P, Schaefer A, Gjoneska E, Tsai LH. A novel molecular class that recruits HDAC/MECP2 complexes to PU.1 motifs reduces neuroinflammation. J Exp Med 2023; 220:e20222105. [PMID: 37642942 PMCID: PMC10465325 DOI: 10.1084/jem.20222105] [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: 12/08/2022] [Revised: 04/26/2023] [Accepted: 07/27/2023] [Indexed: 08/31/2023] Open
Abstract
Pervasive neuroinflammation occurs in many neurodegenerative diseases, including Alzheimer's disease (AD). SPI1/PU.1 is a transcription factor located at a genome-wide significant AD-risk locus and its reduced expression is associated with delayed onset of AD. We analyzed single-cell transcriptomic datasets from microglia of human AD patients and found an enrichment of PU.1-binding motifs in the differentially expressed genes. In hippocampal tissues from transgenic mice with neurodegeneration, we found vastly increased genomic PU.1 binding. We then screened for PU.1 inhibitors using a PU.1 reporter cell line and discovered A11, a molecule with anti-inflammatory efficacy and nanomolar potency. A11 regulated genes putatively by recruiting a repressive complex containing MECP2, HDAC1, SIN3A, and DNMT3A to PU.1 motifs, thus representing a novel mechanism and class of molecules. In mouse models of AD, A11 ameliorated neuroinflammation, loss of neuronal integrity, AD pathology, and improved cognitive performance. This study uncovers a novel class of anti-inflammatory molecules with therapeutic potential for neurodegenerative disorders.
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Affiliation(s)
- William T. Ralvenius
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alison E. Mungenast
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hannah Woolf
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Margaret M. Huston
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Tyler Z. Gillingham
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Stephen K. Godin
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jay Penney
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hugh P. Cam
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Fan Gao
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Celia G. Fernandez
- The Neurodegeneration Consortium, Therapeutics Discovery Division, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Barbara Czako
- The Neurodegeneration Consortium, Therapeutics Discovery Division, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yaima Lightfoot
- The Neurodegeneration Consortium, Therapeutics Discovery Division, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - William J. Ray
- The Neurodegeneration Consortium, Therapeutics Discovery Division, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Adrian Beckmann
- The Neurodegeneration Consortium, Therapeutics Discovery Division, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Alison M. Goate
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Edoardo Marcora
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Carmen Romero-Molina
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pinar Ayata
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Advanced Science Research Center at the Graduate Center, Neuroscience Initiative, City University of New York, New York, NY, USA
| | - Anne Schaefer
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Elizabeta Gjoneska
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, Durham, NC, USA
| | - Li-Huei Tsai
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
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Gul A, Yang F, Xie C, Du W, Mohammadtursun N, Wang B, Le J, Dong J. Pulmonary fibrosis model of mice induced by different administration methods of bleomycin. BMC Pulm Med 2023; 23:91. [PMID: 36944966 PMCID: PMC10029181 DOI: 10.1186/s12890-023-02349-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 02/01/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disease of the lung. How to build a typical human mimicking animal model has been a challenge. Thus, to reveal the mechanism and to make it useful for IPF clinical treatment, a different type of mice model and inspection methods are used to evaluate which one is applicable for the study of IPF. METHOD 69 Twelve-weeks-old C57BL/6 mice were divided into 3 type groups (n = 7 for each control group, n = 8 for each BLM-induced pulmonary fibrosis groups), as intraperitoneal injection, intratracheal administration, and intravenous administration of bleomycin (BLM) to initiate lung fibrosis. Changes of the lung function measured through mice Pulmonary function test (PFT). Morphological changes in mice were observed by PET/CT, Masson and Picro-Sirius staining, Transmission electron microscopy (TEM). Biochemical changes were tested by Enzyme-linked immunosorbent assay (Elisa). RESULTS PET/CT of BLM-receiving mice showed an increase in fibrotic consolidations and an increase in non-aerated lung area in BLM-treated mice compared with that in controls. TGF-b1, TNF-a, IL-6, GM-CSF in BALF and serum. PAI-1, HYP in the lung tissue of mice were significantly different in each BLM groups than those in the controls. The results of Masson staining in mice indicate that the lung tissues of all BLM received groups, the intratracheal groups, the intravenous groups, and the intraperitoneal groups have a higher degree of pulmonary septal thickening and collagen fiber consolidation compare to saline control. Picro-Sirius staining results are consistent with the results of Masson staining. Compared with the saline control group, the ratio of Col 1/Col 3 was significantly increased in each BLM group. TEM results found that in BLM group, type I alveolar epithelial cells were degenerated. Exfoliated endothelial cells were swelling, and type II alveolar epithelial cells were proliferated, the shape of the nucleus was irregular, and some tooth-like protrusions were seen. CONCLUSIONS With three different methods of animal model construction, high dose of each show more compliable, and BLM can successfully induce animal models of pulmonary fibrosis, however, certain differences in the fibrosis formation sites of them three, and tail vein injection of BLM induced PF model is closer to the idiopathic pulmonary interstitial fibrosis.
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Affiliation(s)
- Aman Gul
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
- Central Laboratory, Xinjiang Medical University, Ürümqi, 830011, People's Republic of China
| | - Fangyong Yang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
| | - Cong Xie
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
| | - Wenjing Du
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
| | - Nabijan Mohammadtursun
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
- College of Xinjiang Uyghur Medicine, Hotan, 848000, People's Republic of China
| | - Bin Wang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China
- Medical College of Hexi University, Zhangye, 734000, Gansu, People's Republic of China
| | - Jingjing Le
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China.
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China.
| | - Jingcheng Dong
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, People's Republic of China.
- Institute of Integrated Traditional Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China.
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Zhang L, Wang Y, Liu T, Mao Y, Peng B. Novel Microglia-based Therapeutic Approaches to Neurodegenerative Disorders. Neurosci Bull 2023; 39:491-502. [PMID: 36593381 PMCID: PMC10043109 DOI: 10.1007/s12264-022-01013-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 11/27/2022] [Indexed: 01/04/2023] Open
Abstract
As prominent immune cells in the central nervous system, microglia constantly monitor the environment and provide neuronal protection, which are important functions for maintaining brain homeostasis. In the diseased brain, microglia are crucial mediators of neuroinflammation that regulates a broad spectrum of cellular responses. In this review, we summarize current knowledge on the multifunctional contributions of microglia to homeostasis and their involvement in neurodegeneration. We further provide a comprehensive overview of therapeutic interventions targeting microglia in neurodegenerative diseases. Notably, we propose microglial depletion and subsequent repopulation as promising replacement therapy. Although microglial replacement therapy is still in its infancy, it will likely be a trend in the development of treatments for neurodegenerative diseases due to its versatility and selectivity.
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Affiliation(s)
- Lijuan Zhang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200040, China
| | - Yafei Wang
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200040, China
| | - Taohui Liu
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200040, China
| | - Ying Mao
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200040, China
| | - Bo Peng
- Department of Neurosurgery, Huashan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200040, China. .,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China.
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Microglial debris is cleared by astrocytes via C4b-facilitated phagocytosis and degraded via RUBICON-dependent noncanonical autophagy in mice. Nat Commun 2022; 13:6233. [PMID: 36280666 PMCID: PMC9592609 DOI: 10.1038/s41467-022-33932-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 10/06/2022] [Indexed: 01/18/2023] Open
Abstract
Microglia are important immune cells in the central nervous system (CNS) that undergo turnover throughout the lifespan. If microglial debris is not removed in a timely manner, accumulated debris may influence CNS function. Clearance of microglial debris is crucial for CNS homeostasis. However, underlying mechanisms remain obscure. We here investigate how dead microglia are removed. We find that although microglia can phagocytose microglial debris in vitro, the territory-dependent competition hinders the microglia-to-microglial debris engulfment in vivo. In contrast, microglial debris is mainly phagocytosed by astrocytes in the brain, facilitated by C4b opsonization. The engulfed microglial fragments are then degraded in astrocytes via RUBICON-dependent LC3-associated phagocytosis (LAP), a form of noncanonical autophagy. Interference with C4b-mediated engulfment and subsequent LAP disrupt the removal and degradation of microglial debris, respectively. Together, we elucidate the cellular and molecular mechanisms of microglial debris removal in mice, extending the knowledge on the maintenance of CNS homeostasis.
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NeuroD1 induces microglial apoptosis and cannot induce microglia-to-neuron cross-lineage reprogramming. Neuron 2021; 109:4094-4108.e5. [PMID: 34875233 DOI: 10.1016/j.neuron.2021.11.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/28/2021] [Accepted: 09/24/2021] [Indexed: 11/21/2022]
Abstract
The regenerative capacity of neurons is limited in the central nervous system (CNS), with irreversible neuronal loss upon insult. In contrast, microglia exhibit extraordinary capacity for repopulation. Matsuda et al. (2019) recently reported NeuroD1-induced microglia-to-neuron conversion, aiming to provide an "unlimited" source to regenerate neurons. However, the extent to which NeuroD1 can exert cross-lineage reprogramming of microglia (myeloid lineage) to neurons (neuroectodermal lineage) is unclear. In this study, we unexpectedly found that NeuroD1 cannot convert microglia to neurons in mice. Instead, NeuroD1 expression induces microglial cell death. Moreover, lineage tracing reveals non-specific leakage of similar lentiviruses as previously used for microglia-to-neuron conversion, which confounds the microglia-to-neuron observation. In summary, we demonstrated that NeuroD1 cannot induce microglia-to-neuron cross-lineage reprogramming. We here propose rigid principles for verifying glia-to-neuron conversion. This Matters Arising paper is in response to Matsuda et al. (2019), published in Neuron.
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