1
|
Duan M, Ru X, Zhou J, Li Y, Guo P, Kang W, Li W, Chen Z, Feng H, Chen Y. Endothelial EGLN3-PKM2 signaling induces the formation of acute astrocytic barrier to alleviate immune cell infiltration after subarachnoid hemorrhage. Fluids Barriers CNS 2024; 21:42. [PMID: 38755642 PMCID: PMC11100217 DOI: 10.1186/s12987-024-00550-8] [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: 02/06/2024] [Accepted: 05/09/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND Most subarachnoid hemorrhage (SAH) patients have no obvious hematoma lesions but exhibit blood-brain barrier dysfunction and vasogenic brain edema. However, there is a few days between blood‒brain barrier dysfunction and vasogenic brain edema. The present study sought to investigate whether this phenomenon is caused by endothelial injury induced by the acute astrocytic barrier, also known as the glial limitans. METHODS Bioinformatics analyses of human endothelial cells and astrocytes under hypoxia were performed based on the GEO database. Wild-type, EGLN3 and PKM2 conditional knock-in mice were used to confirm glial limitan formation after SAH. Then, the effect of endothelial EGLN3-PKM2 signaling on temporal and spatial changes in glial limitans was evaluated in both in vivo and in vitro models of SAH. RESULTS The data indicate that in the acute phase after SAH, astrocytes can form a temporary protective barrier, the glia limitans, around blood vessels that helps maintain barrier function and improve neurological prognosis. Molecular docking studies have shown that endothelial cells and astrocytes can promote glial limitans-based protection against early brain injury through EGLN3/PKM2 signaling and further activation of the PKC/ERK/MAPK signaling pathway in astrocytes after SAH. CONCLUSION Improving the ability to maintain glial limitans may be a new therapeutic strategy for improving the prognosis of SAH patients.
Collapse
Affiliation(s)
- Mingxu Duan
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Xufang Ru
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Jiru Zhou
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Yuanshu Li
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Peiwen Guo
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Wenbo Kang
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Wenyan Li
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Zhi Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Hua Feng
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
| | - Yujie Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.
- Chongqing Key Laboratory of Intelligent Diagnosis, Treatment and Rehabilitation of Central Nervous System Injuries, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
| |
Collapse
|
2
|
Buenaventura RG, Harvey AC, Burns MP, Main BS. Traumatic brain injury induces an adaptive immune response in the meningeal transcriptome that is amplified by aging. Front Neurosci 2023; 17:1210175. [PMID: 37588516 PMCID: PMC10425597 DOI: 10.3389/fnins.2023.1210175] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/07/2023] [Indexed: 08/18/2023] Open
Abstract
Traumatic Brain Injury (TBI) is a major cause of disability and mortality, particularly among the elderly, yet our mechanistic understanding of how age renders the post-traumatic brain vulnerable to poor clinical outcomes and susceptible to neurological disease remains poorly understood. It is well established that dysregulated and sustained immune responses contribute to negative outcomes after TBI, however our understanding of the interactions between central and peripheral immune reservoirs is still unclear. The meninges serve as the interface between the brain and the immune system, facilitating important bi-directional roles in healthy and disease settings. It has been previously shown that disruption of this system exacerbates inflammation in age related neurodegenerative disorders such as Alzheimer's disease, however we have an incomplete understanding of how the meningeal compartment influences immune responses after TBI. Here, we examine the meningeal tissue and its response to brain injury in young (3-months) and aged (18-months) mice. Utilizing a bioinformatic approach, high-throughput RNA sequencing demonstrates alterations in the meningeal transcriptome at sub-acute (7-days) and chronic (1 month) timepoints after injury. We find that age alone chronically exacerbates immunoglobulin production and B cell responses. After TBI, adaptive immune response genes are up-regulated in a temporal manner, with genes involved in T cell responses elevated sub-acutely, followed by increases in B cell related genes at chronic time points after injury. Pro-inflammatory cytokines are also implicated as contributing to the immune response in the meninges, with ingenuity pathway analysis identifying interferons as master regulators in aged mice compared to young mice following TBI. Collectively these data demonstrate the temporal series of meningeal specific signatures, providing insights into how age leads to worse neuroinflammatory outcomes in TBI.
Collapse
Affiliation(s)
| | | | | | - Bevan S. Main
- Laboratory for Brain Injury and Dementia, Department of Neuroscience, Georgetown University, Washington, DC, United States
| |
Collapse
|
3
|
Hasel P, Cooper ML, Marchildon AE, Rufen-Blanchette UA, Kim RD, Ma TC, Kang UJ, Chao MV, Liddelow SA. Defining the molecular identity and morphology of glia limitans superficialis astrocytes in mouse and human. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.06.535893. [PMID: 37066303 PMCID: PMC10104130 DOI: 10.1101/2023.04.06.535893] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Astrocytes are a highly abundant glial cell type that perform critical homeostatic functions in the central nervous system. Like neurons, astrocytes have many discrete heterogenous subtypes. The subtype identity and functions are, at least in part, associated with their anatomical location and can be highly restricted to strategically important anatomical domains. Here, we report that astrocytes forming the glia limitans superficialis, the outermost border of brain and spinal cord, are a highly specialized astrocyte subtype and can be identified by a single marker: Myocilin (Myoc). We show that Myoc+ astrocytes cover the entire brain and spinal cord surface, exhibit an atypical morphology, and are evolutionarily conserved from rodents to humans. Identification of this highly specialized astrocyte subtype will advance our understanding of CNS homeostasis and potentially be targeted for therapeutic intervention to combat peripheral inflammatory effects on the CNS.
Collapse
Affiliation(s)
- Philip Hasel
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
| | - Melissa L Cooper
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
| | - Anne E Marchildon
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
| | | | - Rachel D Kim
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
| | - Thong C Ma
- Fresco Institute for Parkinson’s and Movement Disorders, Department of Neurology, NYU Grossman School of Medicine, New York, NY., USA
- Parekh Center for Interdisciplinary Neurology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Neuroscience and Physiology, NYU Grossman School of Medicine, New York, NY., USA
| | - Un Jung Kang
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
- Fresco Institute for Parkinson’s and Movement Disorders, Department of Neurology, NYU Grossman School of Medicine, New York, NY., USA
- Parekh Center for Interdisciplinary Neurology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Neuroscience and Physiology, NYU Grossman School of Medicine, New York, NY., USA
| | - Moses V Chao
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
- Department of Neuroscience and Physiology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Psychiatry, NYU Grossman School of Medicine, New York, NY., USA
| | - Shane A Liddelow
- Neuroscience Institute, NYU Grossman School of Medicine, New York, NY., USA
- Parekh Center for Interdisciplinary Neurology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Neuroscience and Physiology, NYU Grossman School of Medicine, New York, NY., USA
- Department of Ophthalmology, NYU Grossman School of Medicine, New York, NY., USA
| |
Collapse
|
4
|
Zhou J, Guo P, Duan M, Li J, Ru X, Li L, Guo Z, Zhang JH, Feng H, Chen Y, Sun X. EphA4/EphrinB2 signaling mediates pericyte-induced transient glia limitans formation as a secondary protective barrier after subarachnoid hemorrhage in mice. Exp Neurol 2023; 360:114293. [PMID: 36493862 PMCID: PMC10561606 DOI: 10.1016/j.expneurol.2022.114293] [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: 09/16/2022] [Revised: 11/13/2022] [Accepted: 12/04/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND Most patients with subarachnoid hemorrhage (SAH) do not exhibit brain parenchymal injury upon imaging but present significant blood-brain barrier (BBB) disruption and secondary neurological deficits. The aim of this study was to investigate whether stressed astrocytes act as a secondary barrier to exert a protective effect after SAH and to investigate the mechanism of glial limitan formation. METHODS A total of 204 adult male C57BL/6 mice and an endovascular perforation SAH model were employed. The spatiotemporal characteristics of glial limitan formation after SAH were determined by immunofluorescence staining and transmission electron microscopy. The molecular mechanisms by which pericytes regulate glia limitans formation were analyzed using polymerase chain reaction, Western blotting, immunofluorescence staining and ELISA in a pericyte-astrocyte contact coculture system. The findings were validated ex vivo and in vivo using lentiviruses and inhibitors. Finally, pericytes were targeted to regulate glial limitan formation, and the effect of the glia limitans on secondary brain injury after SAH was evaluated by flow cytometry and analysis of neurological function. RESULTS Stress-induced glial limitan formation occurred 1 day after SAH and markedly subsided 3 days after ictus. Pericytes regulated astrocyte glia limitan formation via EphA4/EphrinB2 signaling, inhibited inflammatory cell infiltration and altered neurological function. CONCLUSIONS Astrocyte-derived glia limitans serve as a secondary protective barrier following BBB disruption after SAH in mice, and pericytes can regulate glial limitan formation and alter neurological function via EphA4/EphrinB2 signaling. Strategies for maintaining this secondary protective barrier may be novel treatment approaches for alleviating early brain injury after SAH.
Collapse
Affiliation(s)
- Jiru Zhou
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China; Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Peiwen Guo
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Mingxu Duan
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Junhan Li
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Xufang Ru
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Lin Li
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China; Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Zongduo Guo
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - John H Zhang
- Neuroscience Research Center, Loma Linda University School of Medicine, Loma Linda, CA 92354, United States; Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA 92354, United States
| | - Hua Feng
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Yujie Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China; Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China.
| | - Xiaochuan Sun
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
| |
Collapse
|
5
|
Mason H, Rai G, Kozyr A, De Jonge N, Gliniewicz E, Berg LJ, Wald G, Dorrier C, Henderson MJ, Zakharov A, Dyson T, Audley J, Pettinato AM, Padilha EC, Shah P, Xu X, Leto TL, Simeonov A, Zarember KA, McGavern DB, Gallin JI. Development of an improved and specific inhibitor of NADPH oxidase 2 to treat traumatic brain injury. Redox Biol 2023; 60:102611. [PMID: 36709665 PMCID: PMC9894920 DOI: 10.1016/j.redox.2023.102611] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/22/2022] [Accepted: 01/11/2023] [Indexed: 01/19/2023] Open
Abstract
NADPH oxidases (NOX's), and the reactive oxygen species (ROS) they produce, play an important role in host defense, thyroid hormone synthesis, apoptosis, gene regulation, angiogenesis and other processes. However, overproduction of ROS by these enzymes is associated with cardiovascular disease, fibrosis, traumatic brain injury (TBI) and other diseases. Structural similarities between NOX's have complicated development of specific inhibitors. Here, we report development of NCATS-SM7270, a small molecule optimized from GSK2795039, that inhibited NOX2 in primary human and mouse granulocytes. NCATS-SM7270 specifically inhibited NOX2 and had reduced inhibitory activity against xanthine oxidase in vitro. We also studied the role of several NOX isoforms during mild TBI (mTBI) and demonstrated that NOX2 and, to a lesser extent, NOX1 deficient mice are protected from mTBI pathology, whereas injury is exacerbated in NOX4 knockouts. Given the pathogenic role played by NOX2 in mTBI, we treated mice transcranially with NCATS-SM7270 after injury and revealed a dose-dependent reduction in mTBI induced cortical cell death. This inhibitor also partially reversed cortical damage observed in NOX4 deficient mice following mTBI. These data demonstrate that NCATS-SM7270 is an improved and specific inhibitor of NOX2 capable of protecting mice from NOX2-dependent cell death associated with mTBI.
Collapse
Affiliation(s)
- Hannah Mason
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Ganesha Rai
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Arina Kozyr
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Nathaniel De Jonge
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Emily Gliniewicz
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Lars J. Berg
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Gal Wald
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Cayce Dorrier
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mark J. Henderson
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Alexey Zakharov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Tristan Dyson
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - John Audley
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Anthony M. Pettinato
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Elias Carvalho Padilha
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Pranav Shah
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Xin Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Thomas L. Leto
- Molecular Defenses Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Kol A. Zarember
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA,Corresponding author.
| | - Dorian B. McGavern
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA,Corresponding author.
| | - John I. Gallin
- Clinical Pathophysiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute for Allergy and Infectious Diseases, Bethesda, MD, 20892, USA,Corresponding author.
| |
Collapse
|
6
|
Bhasiin K, Heintz O, Colodner KJ. Optimization and Technical Considerations for the Dye-Exclusion Protocol Used to Assess Blood-Brain Barrier Integrity in Adult Drosophila melanogaster. Int J Mol Sci 2023; 24:ijms24031886. [PMID: 36768206 PMCID: PMC9916281 DOI: 10.3390/ijms24031886] [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: 10/24/2022] [Revised: 01/05/2023] [Accepted: 01/11/2023] [Indexed: 01/21/2023] Open
Abstract
The blood-brain barrier (BBB) is a multicellular construct that regulates the diffusion and transport of metabolites, ions, toxins, and inflammatory mediators into and out of the central nervous system (CNS). Its integrity is essential for proper brain physiology, and its breakdown has been shown to contribute to neurological dysfunction. The BBB in vertebrates exists primarily through the coordination between endothelial cells, pericytes, and astrocytes, while invertebrates, which lack a vascularized circulatory system, typically have a barrier composed of glial cells that separate the CNS from humoral fluids. Notably, the invertebrate barrier is molecularly and functionally analogous to the vertebrate BBB, and the fruit fly, Drosophila melanogaster, is increasingly recognized as a useful model system in which to investigate barrier function. The most widely used technique to assess barrier function in the fly is the dye-exclusion assay, which involves monitoring the infiltration of a fluorescent-coupled dextran into the brain. In this study, we explore analytical and technical considerations of this procedure that yield a more reliable assessment of barrier function, and we validate our findings using a traumatic injury model. Together, we have identified parameters that optimize the dye-exclusion assay and provide an alternative framework for future studies examining barrier function in Drosophila.
Collapse
|
7
|
Mason HD, McGavern DB. How the immune system shapes neurodegenerative diseases. Trends Neurosci 2022; 45:733-748. [PMID: 36075783 PMCID: PMC9746609 DOI: 10.1016/j.tins.2022.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 06/10/2022] [Accepted: 08/01/2022] [Indexed: 12/15/2022]
Abstract
Neurodegenerative diseases are a major cause of death and disability worldwide and are influenced by many factors including age, genetics, and injuries. While these diseases are often thought to result from the accumulation and spread of aberrant proteins, recent studies have demonstrated that they can be shaped by the innate and adaptive immune system. Resident myeloid cells typically mount a sustained response to the degenerating CNS, but peripheral leukocytes such as T and B cells can also alter disease trajectories. Here, we review the sometimes-dichotomous roles played by immune cells during neurodegenerative diseases and explore how brain trauma can serve as a disease initiator or accelerant. We also offer insights into how failure to properly resolve a CNS injury might promote the development of a neurodegenerative disease.
Collapse
Affiliation(s)
- Hannah D Mason
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dorian B McGavern
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
8
|
Stem Cell Therapy for Sequestration of Traumatic Brain Injury-Induced Inflammation. Int J Mol Sci 2022; 23:ijms231810286. [PMID: 36142198 PMCID: PMC9499317 DOI: 10.3390/ijms231810286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/30/2022] [Accepted: 09/04/2022] [Indexed: 11/17/2022] Open
Abstract
Traumatic brain injury (TBI) is one of the leading causes of long-term neurological disabilities in the world. TBI is a signature disease for soldiers and veterans, but also affects civilians, including adults and children. Following TBI, the brain resident and immune cells turn into a “reactive” state, characterized by the production of inflammatory mediators that contribute to the development of cognitive deficits. Other injuries to the brain, including radiation exposure, may trigger TBI-like pathology, characterized by inflammation. Currently there are no treatments to prevent or reverse the deleterious consequences of brain trauma. The recognition that TBI predisposes stem cell alterations suggests that stem cell-based therapies stand as a potential treatment for TBI. Here, we discuss the inflamed brain after TBI and radiation injury. We further review the status of stem cells in the inflamed brain and the applications of cell therapy in sequestering inflammation in TBI.
Collapse
|
9
|
Buckley MW, McGavern DB. Immune dynamics in the CNS and its barriers during homeostasis and disease. Immunol Rev 2022; 306:58-75. [PMID: 35067941 PMCID: PMC8852772 DOI: 10.1111/imr.13066] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 12/11/2022]
Abstract
The central nervous system (CNS) has historically been viewed as an immunologically privileged site, but recent studies have uncovered a vast landscape of immune cells that reside primarily along its borders. While microglia are largely responsible for surveying the parenchyma, CNS barrier sites are inhabited by a plethora of different innate and adaptive immune cells that participate in everything from the defense against microbes to the maintenance of neural function. Static and dynamic imaging studies have revolutionized the field of neuroimmunology by providing detailed maps of CNS immune cells as well as information about how these cells move, organize, and interact during steady-state and inflammatory conditions. These studies have also redefined our understanding of neural-immune interactions at a cellular level and reshaped our conceptual view of immune privilege in this specialized compartment. This review will focus on insights gained using imaging techniques in the field of neuroimmunology, with an emphasis on anatomy and CNS immune dynamics during homeostasis, infectious diseases, injuries, and aging.
Collapse
Affiliation(s)
- Monica W. Buckley
- Viral Immunology and Intravital Imaging Section National Institute of Neurological Disorders and Stroke National Institutes of Health Bethesda Maryland USA
| | - Dorian B. McGavern
- Viral Immunology and Intravital Imaging Section National Institute of Neurological Disorders and Stroke National Institutes of Health Bethesda Maryland USA
| |
Collapse
|