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VanderZwaag J, Tremblay MÈ. A Neuronal Activity-Boosting Microglial Function in Post-Anesthetic Emergence: How Microglial-Neuronal Crosstalk May Alter States of Consciousness. Neurosci Bull 2024; 40:1590-1592. [PMID: 39190096 PMCID: PMC11422326 DOI: 10.1007/s12264-024-01256-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 04/26/2024] [Indexed: 08/28/2024] Open
Affiliation(s)
- Jared VanderZwaag
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada.
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada.
- Neurology and Neurosurgery Department, McGill University, Montreal, QC, Canada.
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada.
- Institute for Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
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Jiao X, Wan J, Wu W, Ma L, Chen C, Dong W, Liu Y, Jin C, Sun A, Zhou Y, Li Z, Liu Q, Wu Y, Zhou C. GLT-1 downregulation in hippocampal astrocytes induced by type 2 diabetes contributes to postoperative cognitive dysfunction in adult mice. CNS Neurosci Ther 2024; 30:e70024. [PMID: 39218798 PMCID: PMC11366448 DOI: 10.1111/cns.70024] [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: 06/18/2024] [Revised: 08/06/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
AIMS Type 2 diabetes mellitus (T2DM) is related to an increased risk of postoperative cognitive dysfunction (POCD), which may be caused by neuronal hyperexcitability. Astrocyte glutamate transporter 1 (GLT-1) plays a crucial role in regulating neuron excitability. We investigated if T2DM would magnify the increased neuronal excitability induced by anesthesia/surgery (A/S) and lead to POCD in young adult mice, and if so, determined whether these effects were associated with GLT-1 expression. METHODS T2DM model was induced by high fat diet (HFD) and injecting STZ. Then, we evaluated the spatial learning and memory of T2DM mice after A/S with the novel object recognition test (NORT) and object location test (OLT). Western blotting and immunofluorescence were used to analyze the expression levels of GLT-1 and neuronal excitability. Oxidative stress reaction and neuronal apoptosis were detected with SOD2 expression, MMP level, and Tunel staining. Hippocampal functional synaptic plasticity was assessed with long-term potentiation (LTP). In the intervention study, we overexpressed hippocampal astrocyte GLT-1 in GFAP-Cre mice. Besides, AAV-Camkllα-hM4Di-mCherry was injected to inhibit neuronal hyperexcitability in CA1 region. RESULTS Our study found T2DM but not A/S reduced GLT-1 expression in hippocampal astrocytes. Interestingly, GLT-1 deficiency alone couldn't lead to cognitive decline, but the downregulation of GLT-1 in T2DM mice obviously enhanced increased hippocampal glutamatergic neuron excitability induced by A/S. The hyperexcitability caused neuronal apoptosis and cognitive impairment. Overexpression of GLT-1 rescued postoperative cognitive dysfunction, glutamatergic neuron hyperexcitability, oxidative stress reaction, and apoptosis in hippocampus. Moreover, chemogenetic inhibition of hippocampal glutamatergic neurons reduced oxidative stress and apoptosis and alleviated postoperative cognitive dysfunction. CONCLUSIONS These findings suggest that the adult mice with type 2 diabetes are at an increased risk of developing POCD, perhaps due to the downregulation of GLT-1 in hippocampal astrocytes, which enhances increased glutamatergic neuron excitability induced by A/S and leads to oxidative stress reaction, and neuronal apoptosis.
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Affiliation(s)
- Xin‐Hao Jiao
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Jie Wan
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Wei‐Feng Wu
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
- Department of Anesthesiology and Perioperative Medicine, Shanghai Fourth People's Hospital, School of MedicineTongji UniversityShanghaiChina
| | - Lin‐Hui Ma
- Department of Anesthesiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Chen Chen
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Wei Dong
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Yi‐Qi Liu
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Chun‐Hui Jin
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Ao Sun
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Yue Zhou
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Zi‐Yi Li
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Qiang Liu
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
- Department of Anesthesiology and Perioperative Medicine, Shanghai Fourth People's Hospital, School of MedicineTongji UniversityShanghaiChina
| | - Yu‐Qing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Cheng‐Hua Zhou
- Jiangsu Key Laboratory of New Drug Research and Clinical PharmacyXuzhou Medical UniversityXuzhouChina
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3
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Wang X, Yi R, Liang X, Zhang N, Zhong F, Lu Y, Chen W, Yu T, Zhang L, Wang H, Zhou L. Myelin modulates the process of isoflurane anesthesia through the regulation of neural activity. CNS Neurosci Ther 2024; 30:e14922. [PMID: 39138640 PMCID: PMC11322027 DOI: 10.1111/cns.14922] [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: 03/14/2024] [Revised: 07/01/2024] [Accepted: 08/04/2024] [Indexed: 08/15/2024] Open
Abstract
AIMS The mechanism underlying the reversible unconsciousness induced by general anesthetics (GA) remains unclear. Recent studies revealed the critical roles of myelin and oligodendrocytes (OLs) in higher functions of the brain. However, it is unknown whether myelin actively participates in the regulation of GA. The aim of this study is to investigate the roles and possible mechanisms of myelin in the regulation of consciousness alterations induced by isoflurane anesthesia. METHODS First, demyelination models for the entire brain and specific neural nuclei were established to investigate the potential role of myelination in the regulation of GA, as well as its possible regional specificity. c-Fos staining was then performed on the demyelinated nuclei to verify the impact of myelin loss on neuronal activity. Finally, the activity of neurons during isoflurane anesthesia in demyelinated mice was recorded by optical fiber photometric calcium signal. The related behavioral indicators and EEG were recorded and analyzed. RESULTS A prolonged emergence time was observed from isoflurane anesthesia in demyelinated mice, which suggested the involvement of myelin in regulating GA. The demyelination in distinct nuclei by LPC further clarified the region-specific roles of isoflurane anesthesia regulation by myelin. The effect of demyelination on isoflurane anesthesia in the certain nucleus was consistent with that in neurons towards isoflurane anesthesia. Finally, we found that the mechanism of myelin in the modulation of isoflurane anesthesia is possibly through the regulation of neuronal activity. CONCLUSIONS In brief, myelin in the distinct neural nucleus plays an essential role in regulating the process of isoflurane anesthesia. The possible mechanism of myelin in the regulation of isoflurane anesthesia is neuronal activity modification by myelin integrity during GA. Our findings enhanced the comprehension of myelin function, and offered a fresh perspective for investigating the neural mechanisms of GA.
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Affiliation(s)
- Xu Wang
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Rulan Yi
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
- Department of AnesthesiologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Xiaoling Liang
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Ning Zhang
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Fuwang Zhong
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Yali Lu
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Wenjia Chen
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
| | - Tian Yu
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
- Department of AnesthesiologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Linyong Zhang
- Department of AnesthesiologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Haiying Wang
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
- Department of AnesthesiologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Liang Zhou
- Key Laboratory of Anesthesia and Organ Protection (Zunyi Medical University), Ministry of EducationZunyi Medical UniversityZunyiChina
- Key Laboratory of Brain ScienceZunyi Medical UniversityZunyiChina
- Guizhou Key Laboratory of Anesthesia and Organ ProtectionZunyi Medical UniversityZunyiChina
- Department of AnesthesiologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
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Xie M, Miller AS, Pallegar PN, Umpierre A, Liang Y, Wang N, Zhang S, Nagaraj NK, Fogarty ZC, Ghayal NB, Oskarsson B, Zhao S, Zheng J, Qi F, Nguyen A, Dickson DW, Wu LJ. Rod-shaped microglia interact with neuronal dendrites to regulate cortical excitability in TDP-43 related neurodegeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.30.601396. [PMID: 39005475 PMCID: PMC11244918 DOI: 10.1101/2024.06.30.601396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Motor cortical hyperexcitability is well-documented in the presymptomatic stage of amyotrophic lateral sclerosis (ALS). However, the mechanisms underlying this early dysregulation are not fully understood. Microglia, as the principal immune cells of the central nervous system, have emerged as important players in sensing and regulating neuronal activity. Here we investigated the role of microglia in the motor cortical circuits in a mouse model of TDP-43 neurodegeneration (rNLS8). Utilizing multichannel probe recording and longitudinal in vivo calcium imaging in awake mice, we observed neuronal hyperactivity at the initial stage of disease progression. Spatial and single-cell RNA sequencing revealed that microglia are the primary responders to motor cortical hyperactivity. We further identified a unique subpopulation of microglia, rod-shaped microglia, which are characterized by a distinct morphology and transcriptional profile. Notably, rod-shaped microglia predominantly interact with neuronal dendrites and excitatory synaptic inputs to attenuate motor cortical hyperactivity. The elimination of rod-shaped microglia through TREM2 deficiency increased neuronal hyperactivity, exacerbated motor deficits, and further decreased survival rates of rNLS8 mice. Together, our results suggest that rod-shaped microglia play a neuroprotective role by attenuating cortical hyperexcitability in the mouse model of TDP-43 related neurodegeneration.
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Guan X, Zhu S, Song J, Liu K, Liu M, Xie L, Wang Y, Wu J, Xu X, Pang T. Microglial CMPK2 promotes neuroinflammation and brain injury after ischemic stroke. Cell Rep Med 2024; 5:101522. [PMID: 38701781 PMCID: PMC11148565 DOI: 10.1016/j.xcrm.2024.101522] [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: 10/29/2023] [Revised: 02/08/2024] [Accepted: 03/28/2024] [Indexed: 05/05/2024]
Abstract
Neuroinflammation plays a significant role in ischemic injury, which can be promoted by oxidized mitochondrial DNA (Ox-mtDNA). Cytidine/uridine monophosphate kinase 2 (CMPK2) regulates mtDNA replication, but its role in neuroinflammation and ischemic injury remains unknown. Here, we report that CMPK2 expression is upregulated in monocytes/macrophages and microglia post-stroke in humans and mice, respectively. Microglia/macrophage CMPK2 knockdown using the Cre recombination-dependent adeno-associated virus suppresses the inflammatory responses in the brain, reduces infarcts, and improves neurological outcomes in ischemic CX3CR1Cre/ERT2 mice. Mechanistically, CMPK2 knockdown limits newly synthesized mtDNA and Ox-mtDNA formation and subsequently blocks NLRP3 inflammasome activation in microglia/macrophages. Nordihydroguaiaretic acid (NDGA), as a CMPK2 inhibitor, is discovered to reduce neuroinflammation and ischemic injury in mice and prevent the inflammatory responses in primary human monocytes from ischemic patients. Thus, these findings identify CMPK2 as a promising therapeutic target for ischemic stroke and other brain disorders associated with neuroinflammation.
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Affiliation(s)
- Xin Guan
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Sitong Zhu
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Jinqian Song
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Kui Liu
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Mei Liu
- Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing 210011, P.R. China
| | - Luyang Xie
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Yifang Wang
- Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing 210011, P.R. China
| | - Jin Wu
- Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing 210011, P.R. China.
| | - Xiaojun Xu
- Department of Pharmacy, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Center for Innovative Traditional Chinese Medicine Target and New Drug Research, International Institutes of Medicine, Zhejiang University, Yiwu, Zhejiang Province 322000, P.R. China.
| | - Tao Pang
- State Key Laboratory of Natural Medicines, New Drug Screening Center, Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, P.R. China; State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210023, P.R. China.
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6
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Pesti I, Légrádi Á, Farkas E. Primary microglia cell cultures in translational research: Strengths and limitations. J Biotechnol 2024; 386:10-18. [PMID: 38519034 DOI: 10.1016/j.jbiotec.2024.03.005] [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: 02/08/2024] [Revised: 03/13/2024] [Accepted: 03/13/2024] [Indexed: 03/24/2024]
Abstract
Microglia are the resident macrophages in the central nervous system, accounting for 10-15% of the cell mass in the brain. Next to their physiological role in development, monitoring neuronal function and the maintenance of homeostasis, microglia are crucial in the brain's immune defense. Brain injury and chronic neurological disorders are associated with neuroinflammation, in which microglia activation is a central element. Microglia acquire a wide spectrum of activation states in the diseased or injured brain, some of which are neurotoxic. The investigation of microglia (patho)physiology and therapeutic interventions targeting neuroinflammation is a substantial challenge. In addition to in vivo approaches, the application of in vitro model systems has gained significant ground and is essential to complement in vivo work. Primary microglia cultures have proved to be a useful tool. Microglia cultures have offered the opportunity to explore the mechanistic, molecular elements of microglia activation, the microglia secretome, and the efficacy of therapeutic treatments against neuroinflammation. As all model systems, primary microglia cultures have distinct strengths and limitations to be weighed when experiments are designed and when data are interpreted. Here, we set out to provide a succinct overview of the advantages and pitfalls of the use of microglia cultures, which instructs the refinement and further development of this technique to remain useful in the toolbox of microglia researchers. Since there is no conclusive therapy to combat neurotoxicity linked to neuroinflammation in acute brain injury or neurodegenerative disorders, these research tools remain essential to explore therapeutic opportunities.
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Affiliation(s)
- István Pesti
- Hungarian Centre of Excellence for Molecular Medicine - University of Szeged Cerebral Blood Flow and Metabolism Research Group, Somogyi u 4, Szeged 6720, Hungary; Department of Cell Biology and Molecular Medicine, Albert Szent-Györgyi Medical School and Faculty of Science and Informatics, University of Szeged, Somogyi u 4, Szeged 6720, Hungary
| | - Ádám Légrádi
- Department of Cell Biology and Molecular Medicine, Albert Szent-Györgyi Medical School and Faculty of Science and Informatics, University of Szeged, Somogyi u 4, Szeged 6720, Hungary
| | - Eszter Farkas
- Hungarian Centre of Excellence for Molecular Medicine - University of Szeged Cerebral Blood Flow and Metabolism Research Group, Somogyi u 4, Szeged 6720, Hungary; Department of Cell Biology and Molecular Medicine, Albert Szent-Györgyi Medical School and Faculty of Science and Informatics, University of Szeged, Somogyi u 4, Szeged 6720, Hungary.
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7
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Escoubas CC, Molofsky AV. Microglia as integrators of brain-associated molecular patterns. Trends Immunol 2024; 45:358-370. [PMID: 38658221 DOI: 10.1016/j.it.2024.03.009] [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: 03/01/2024] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 04/26/2024]
Abstract
Microglia are brain-resident macrophages that play key roles in brain development and experience dependent plasticity. In this review we discuss recent findings regarding the molecular mechanisms through which mammalian microglia sense the unique molecular patterns of the homeostatic brain. We propose that microglial function is acutely controlled in response to 'brain-associated molecular patterns' (BAMPs) that function as indicators of neuronal activity and neural circuit remodeling. A further layer of regulation comes from instructive cytokine cues that define unique microglial functional states. A systematic investigation of the receptors and signaling pathways that mediate these two regulatory axes may begin to define a functional code for microglia-neuron interactions.
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Affiliation(s)
- Caroline C Escoubas
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA 94158, USA
| | - Anna V Molofsky
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA 94158, USA.
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8
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Zhao S, Umpierre AD, Wu LJ. Tuning neural circuits and behaviors by microglia in the adult brain. Trends Neurosci 2024; 47:181-194. [PMID: 38245380 PMCID: PMC10939815 DOI: 10.1016/j.tins.2023.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 11/04/2023] [Accepted: 12/21/2023] [Indexed: 01/22/2024]
Abstract
Microglia are the primary immune cells of the CNS, contributing to both inflammatory damage and tissue repair in neurological disorder. In addition, emerging evidence highlights the role of homeostatic microglia in regulating neuronal activity, interacting with synapses, tuning neural circuits, and modulating behaviors. Herein, we review how microglia sense and regulate neuronal activity through synaptic interactions, thereby directly engaging with neural networks and behaviors. We discuss current studies utilizing microglial optogenetic and chemogenetic approaches to modulate adult neural circuits. These manipulations of microglia across different CNS regions lead to diverse behavioral consequences. We propose that spatial heterogeneity of microglia-neuron interaction lays the groundwork for understanding diverse functions of microglia in neural circuits and behaviors.
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Affiliation(s)
- Shunyi Zhao
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | | | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Department of Immunology, Mayo Clinic, Rochester, MN, USA; Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.
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9
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Peng B, Rao Y, Wang Y, Duan S, Qi H, Yang J, Zhang H. Immunology reshapes neuroscience, and neuroscience reshapes immunology. FUNDAMENTAL RESEARCH 2024; 4:199-200. [PMID: 38933513 PMCID: PMC11197736 DOI: 10.1016/j.fmre.2024.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024] Open
Affiliation(s)
- 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 University, Shanghai 200040, China
| | - Yanxia Rao
- Department of Laboratory Animal Science, MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Yun Wang
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
| | - Shumin Duan
- Faculty of Medicine and Pharmaceutical Sciences, Zhejiang University, Hangzhou 310014, China
| | - Hai Qi
- School of Medicine, Tsinghua University, Beijing 100084, China
| | - Jing Yang
- IDG/McGovern Institute for Brain Research, Center for Life Sciences, School of Life Sciences, Peking University, Beijing 100871, China
- Chinese Institute for Brain Research, Beijing 102206, China
| | - Hongliang Zhang
- Department of Life Sciences, National Natural Science Foundation of China, Beijing 100085, China
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10
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Zhao S, Wang L, Liang Y, Zheng J, Umpierre AD, Wu LJ. Chemogenetic activation of microglial Gi signaling decreases microglial surveillance and impairs neuronal synchronization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.12.579861. [PMID: 38405754 PMCID: PMC10888941 DOI: 10.1101/2024.02.12.579861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Microglia actively survey the brain and dynamically interact with neurons to maintain brain homeostasis. Microglial Gi-protein coupled receptors (Gi-GPCRs) play a critical role in microglia-neuron communications. However, the impact of temporally activating microglial Gi signaling on microglial dynamics and neuronal activity in the homeostatic brain remains largely unknown. In this study, we employed Gi-based Designer Receptors Exclusively Activated by Designer Drugs (Gi-DREADD) to selectively and temporally modulate microglial Gi signaling pathway. By integrating this chemogenetic approach with in vivo two-photon imaging, we observed that exogenous activation of microglial Gi signaling transiently inhibited microglial process dynamics, reduced neuronal activity, and impaired neuronal synchronization. These altered neuronal functions were associated with a decrease in interactions between microglia and neuron somata. Altogether, this study demonstrates that acute, exogenous activation of microglial Gi signaling can regulate neuronal circuit function, offering a potential pharmacological target for neuromodulation through microglia.
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