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Ling T, Yin A, Cao Y, Li J, Li H, Zhou Y, Guo X, Li J, Zhang R, Wu H, Li P. Purinergic Astrocyte Signaling Driven by TNF-α After Cannabidiol Administration Restores Normal Synaptic Remodeling Following Traumatic Brain Injury. Neuroscience 2024; 545:31-46. [PMID: 38460903 DOI: 10.1016/j.neuroscience.2024.03.002] [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: 09/26/2023] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/11/2024]
Abstract
Traumatic brain injury (TBI) is a prevalent form of cranial trauma that results in neural conduction disruptions and damage to synaptic structures and functions. Cannabidiol (CBD), a primary derivative from plant-based cannabinoids, exhibits a range of beneficial effects, including analgesic, sedative, anti-inflammatory, anticonvulsant, anti-anxiety, anti-apoptotic, and neuroprotective properties. Nevertheless, the effects of synaptic reconstruction and the mechanisms underlying these effects remain poorly understood. TBI is characterized by increased levels of tumor necrosis factor-alpha (TNF-α), a cytokine integral for the modulation of glutamate release by astrocytes. In the present study, the potential of CBD in regulating aberrant glutamate signal transmission in astrocytes following brain injury, as well as the underlying mechanisms involved, were investigated using immunofluorescence double staining, enzyme-linked immunosorbent assay (ELISA), western blot analysis, hematoxylin and eosin (H&E) staining, Nissl staining, transmission electron microscopy, and RT-qPCR. In this study, we examined the impact of CBD on neuronal synapses, focusing on the TNF-α-driven purinergic signaling pathway. Specifically, our research revealed that CBD pretreatment effectively reduced the secretion of TNF-α induced by astrocyte activation following TBI. This reduction inhibited the interaction between TNF-α and P2Y1 receptors, leading to a decrease in the release of neurotransmitters, including Ca2+ and glutamate, thereby initiating synaptic remodeling. Our study showed that CBD exhibits significant therapeutic potential for TBI-related synaptic dysfunction, offering valuable insights for future research and more effective TBI treatments. Further exploration of the potential applications of CBD in neuroprotection is required to develop innovative clinical strategies.
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Affiliation(s)
- Tenghan Ling
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Aiping Yin
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Yan Cao
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Jiali Li
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Hengxi Li
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Ying Zhou
- Department of Kunming Medical University Electron Microscope Laboratory, Kunming Medical University, Kunming 650500, China.
| | - Xiaobing Guo
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
| | - Jinghui Li
- Department of Neurosurgery, The First Affiliated Hospital of Kunming Medical University, Kunming 650032, China.
| | - Ruilin Zhang
- Department of Forensic Medicine of Kunming Medical University, Kunming 650500, China.
| | - Haiying Wu
- Department of Emergency and Intensive Care Unit, The First Affiliated Hospital, Kunming Medical University, Kunming 650032, China.
| | - Ping Li
- Department of Anatomy and Histology/Embryology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming 650500, China.
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Adewale Q, Khan AF, Bennett DA, Iturria-Medina Y. Single-nucleus RNA velocity reveals critical synaptic and cell-cycle dysregulations in neuropathologically confirmed Alzheimer's disease. Sci Rep 2024; 14:7269. [PMID: 38538816 PMCID: PMC10973452 DOI: 10.1038/s41598-024-57918-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 03/21/2024] [Indexed: 04/26/2024] Open
Abstract
Typical differential single-nucleus gene expression (snRNA-seq) analyses in Alzheimer's disease (AD) provide fixed snapshots of cellular alterations, making the accurate detection of temporal cell changes challenging. To characterize the dynamic cellular and transcriptomic differences in AD neuropathology, we apply the novel concept of RNA velocity to the study of single-nucleus RNA from the cortex of 60 subjects with varied levels of AD pathology. RNA velocity captures the rate of change of gene expression by comparing intronic and exonic sequence counts. We performed differential analyses to find the significant genes driving both cell type-specific RNA velocity and expression differences in AD, extensively compared these two transcriptomic metrics, and clarified their associations with multiple neuropathologic traits. The results were cross-validated in an independent dataset. Comparison of AD pathology-associated RNA velocity with parallel gene expression differences reveals sets of genes and molecular pathways that underlie the dynamic and static regimes of cell type-specific dysregulations underlying the disease. Differential RNA velocity and its linked progressive neuropathology point to significant dysregulations in synaptic organization and cell development across cell types. Notably, most of the genes underlying this synaptic dysregulation showed increased RNA velocity in AD subjects compared to controls. Accelerated cell changes were also observed in the AD subjects, suggesting that the precocious depletion of precursor cell pools might be associated with neurodegeneration. Overall, this study uncovers active molecular drivers of the spatiotemporal alterations in AD and offers novel insights towards gene- and cell-centric therapeutic strategies accounting for dynamic cell perturbations and synaptic disruptions.
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Affiliation(s)
- Quadri Adewale
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada
| | - Ahmed F Khan
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada.
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada.
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada.
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Strong TA, Esquivel J, Wang Q, Ledon PJ, Wang H, Gaidosh G, Tse D, Pelaez D. Activation of multiple Eph receptors on neuronal membranes correlates with the onset of optic neuropathy. EYE AND VISION (LONDON, ENGLAND) 2023; 10:42. [PMID: 37779186 PMCID: PMC10544557 DOI: 10.1186/s40662-023-00359-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 09/11/2023] [Indexed: 10/03/2023]
Abstract
BACKGROUND Optic neuropathy is a major cause of irreversible blindness, yet the molecular determinants that contribute to neuronal demise have not been fully elucidated. Several studies have identified 'ephrin signaling' as one of the most dysregulated pathways in the early pathophysiology of optic neuropathy with varied etiologies. Developmentally, gradients in ephrin signaling coordinate retinotopic mapping via repulsive modulation of cytoskeletal dynamics in neuronal membranes. Little is known about the role ephrin signaling plays in the post-natal visual system and its correlation with the onset of optic neuropathy. METHODS Postnatal mouse retinas were collected for mass spectrometry analysis for erythropoietin-producing human hepatocellular (Eph) receptors. Optic nerve crush (ONC) model was employed to induce optic neuropathy, and proteomic changes during the acute phase of neuropathic onset were analyzed. Confocal and super-resolution microscopy determined the cellular localization of activated Eph receptors after ONC injury. Eph receptor inhibitors assessed the neuroprotective effect of ephrin signaling modulation. RESULTS Mass spectrometry revealed expression of seven Eph receptors (EphA2, A4, A5, B1, B2, B3, and B6) in postnatal mouse retinal tissue. Immunoblotting analysis indicated a significant increase in phosphorylation of these Eph receptors 48 h after ONC. Confocal microscopy demonstrated the presence of both subclasses of Eph receptors within the retina. Stochastic optical reconstruction microscopy (STORM) super-resolution imaging combined with optimal transport colocalization analysis revealed a significant co-localization of activated Eph receptors with injured neuronal cells, compared to uninjured neuronal and/or injured glial cells, 48 h post-ONC. Eph receptor inhibitors displayed notable neuroprotective effects for retinal ganglion cells (RGCs) after six days of ONC injury. CONCLUSIONS Our findings demonstrate the functional presence of diverse Eph receptors in the postnatal mammalian retina, capable of modulating multiple biological processes. Pan-Eph receptor activation contributes to the onset of neuropathy in optic neuropathies, with preferential activation of Eph receptors on neuronal processes in the inner retina following optic nerve injury. Notably, Eph receptor activation precedes neuronal loss. We observed a neuroprotective effect on RGCs upon inhibiting Eph receptors. Our study highlights the importance of investigating this repulsive pathway in early optic neuropathies and provides a comprehensive characterization of the receptors present in the developed retina of mice, relevant to both homeostasis and disease processes.
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Affiliation(s)
- Thomas A Strong
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, USA
| | - Juan Esquivel
- Department of Physics, University of Florida College of Liberal Arts and Sciences, Gainesville, FL, USA
| | - Qikai Wang
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA
| | - Paul J Ledon
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Hua Wang
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA
| | - Gabriel Gaidosh
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - David Tse
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA
| | - Daniel Pelaez
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA.
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 1638 NW 10th Avenue, Miami, FL, 33136, USA.
- Department of Biomedical Engineering, University of Miami College of Engineering, University of Miami, Coral Gables, FL, USA.
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, USA.
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA.
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Thompson D, Odufuwa AE, Brissette CA, Watt JA. Transcriptome and methylome of the supraoptic nucleus provides insights into the age-dependent loss of neuronal plasticity. Front Aging Neurosci 2023; 15:1223273. [PMID: 37711995 PMCID: PMC10498476 DOI: 10.3389/fnagi.2023.1223273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/08/2023] [Indexed: 09/16/2023] Open
Abstract
The age-dependent loss of neuronal plasticity is a well-known phenomenon that is poorly understood. The loss of this capacity for axonal regeneration is emphasized following traumatic brain injury, which is a major cause of disability and death among adults in the US. We have previously shown the intrinsic capacity of magnocellular neurons within the supraoptic nucleus to undergo axonal regeneration following unilateral axotomization in an age-dependent manner. The aim of this research was to determine the age-dependent molecular mechanisms that may underlie this phenomenon. As such, we characterized the transcriptome and DNA methylome of the supraoptic nucleus in uninjured 35-day old rats and 125-day old rats. Our data indicates the downregulation of a large number of axonogenesis related transcripts in 125-day old rats compared to 35-day old rats. Specifically, several semaphorin and ephrin genes were downregulated, as well as growth factors including FGF's, insulin-like growth factors (IGFs), and brain-derived neurotrophic factor (BDNF). Differential methylation analysis indicates enrichment of biological processes involved in axonogenesis and axon guidance. Conversely, we observed a robust and specific upregulation of MHCI related transcripts. This may involve the activator protein 1 (AP-1) transcription factor complex as motif analysis of differentially methylated regions indicate enrichment of AP-1 binding sites in hypomethylated regions. Together, our data suggests a loss of pro-regenerative capabilities with age which would prevent axonal growth and appropriate innervation following injury.
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Affiliation(s)
| | | | | | - John A. Watt
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, United States
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Strong TA, Esquivel J, Wang Q, Ledon PJ, Wang H, Gaidosh G, Tse D, Pelaez D. Activation of Multiple Eph Receptors on Neuronal Membranes Correlates with The Onset of Traumatic Optic Neuropathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.05.543735. [PMID: 37333178 PMCID: PMC10274644 DOI: 10.1101/2023.06.05.543735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Background Optic neuropathy (ON) is a major cause of irreversible blindness, yet the molecular determinants that contribute to neuronal demise have not been fully elucidated. Several studies have identified 'ephrin signaling' as one of the most dysregulated pathways in the early pathophysiology of ON with varied etiologies. Developmentally, gradients in ephrin signaling coordinate retinotopic mapping via repulsive modulation of cytoskeletal dynamics in neuronal membranes. Little is known about the role ephrin signaling played in the post-natal visual system and its correlation with the onset of optic neuropathy. Methods Postnatal mouse retinas were collected for mass spectrometry analysis for Eph receptors. Optic nerve crush (ONC) model was employed to induce optic neuropathy, and proteomic changes during the acute phase of neuropathic onset were analyzed. Confocal and super-resolution microscopy determined the cellular localization of activated Eph receptors after ONC injury. Eph receptor inhibitors assessed the neuroprotective effect of ephrin signaling modulation. Results Mass spectrometry revealed expression of seven Eph receptors (EphA2, A4, A5, B1, B2, B3, and B6) in postnatal mouse retinal tissue. Immunoblotting analysis indicated a significant increase in phosphorylation of these Eph receptors 48 hours after ONC. Confocal microscopy demonstrated the presence of both subclasses of Eph receptors in the inner retinal layers. STORM super-resolution imaging combined with optimal transport colocalization analysis revealed a significant co-localization of activated Eph receptors with injured neuronal processes, compared to uninjured neuronal and/or injured glial cells, 48 hours post-ONC. Eph receptor inhibitors displayed notable neuroprotective effects after 6 days of ONC injury. Conclusions Our findings demonstrate the functional presence of diverse Eph receptors in the postnatal mammalian retina, capable of modulating multiple biological processes. Pan-Eph receptor activation contributes to the onset of neuropathy in ONs, with preferential activation of Eph receptors on neuronal processes in the inner retina following optic nerve injury. Notably, Eph receptor activation precedes neuronal loss. We observed neuroprotective effects upon inhibiting Eph receptors. Our study highlights the importance of investigating this repulsive pathway in early optic neuropathies and provides a comprehensive characterization of the receptors present in the developed retina of mice, relevant to both homeostasis and disease processes.
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Affiliation(s)
- Thomas A. Strong
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Department of Cell Biology, University of Miami Miller School of Medicine
| | - Juan Esquivel
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Qikai Wang
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Paul J. Ledon
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Hua Wang
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Gabriel Gaidosh
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - David Tse
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Daniel Pelaez
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Dr. Nasser Al-Rashid Orbital Vision Research Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States of America
- Department of Biomedical Engineering, University of Miami College of Engineering, University of Miami, Coral Gables, FL, United States of America
- Department of Cell Biology, University of Miami Miller School of Medicine
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, United States of America
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Kodali M, Madhu LN, Reger RL, Milutinovic B, Upadhya R, Attaluri S, Shuai B, Shankar G, Shetty AK. A single intranasal dose of human mesenchymal stem cell-derived extracellular vesicles after traumatic brain injury eases neurogenesis decline, synapse loss, and BDNF-ERK-CREB signaling. Front Mol Neurosci 2023; 16:1185883. [PMID: 37284464 PMCID: PMC10239975 DOI: 10.3389/fnmol.2023.1185883] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 04/28/2023] [Indexed: 06/08/2023] Open
Abstract
An optimal intranasal (IN) dose of human mesenchymal stem cell-derived extracellular vesicles (hMSC-EVs), 90 min post-traumatic brain injury (TBI), has been reported to prevent the evolution of acute neuroinflammation into chronic neuroinflammation resulting in the alleviation of long-term cognitive and mood impairments. Since hippocampal neurogenesis decline and synapse loss contribute to TBI-induced long-term cognitive and mood dysfunction, this study investigated whether hMSC-EV treatment after TBI can prevent hippocampal neurogenesis decline and synapse loss in the chronic phase of TBI. C57BL6 mice undergoing unilateral controlled cortical impact injury (CCI) received a single IN administration of different doses of EVs or the vehicle at 90 min post-TBI. Quantifying neurogenesis in the subgranular zone-granule cell layer (SGZ-GCL) through 5'-bromodeoxyuridine and neuron-specific nuclear antigen double labeling at ~2 months post-TBI revealed decreased neurogenesis in TBI mice receiving vehicle. However, in TBI mice receiving EVs (12.8 and 25.6 × 109 EVs), the extent of neurogenesis was matched to naive control levels. A similar trend of decreased neurogenesis was seen when doublecortin-positive newly generated neurons were quantified in the SGZ-GCL at ~3 months post-TBI. The above doses of EVs treatment after TBI also reduced the loss of pre-and post-synaptic marker proteins in the hippocampus and the somatosensory cortex. Moreover, at 48 h post-treatment, brain-derived neurotrophic factor (BDNF), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), and phosphorylated cyclic AMP response-element binding protein (p-CREB) levels were downregulated in TBI mice receiving the vehicle but were closer to naïve control levels in TBI mice receiving above doses of hMSC-EVs. Notably, improved BDNF concentration observed in TBI mice receiving hMSC-EVs in the acute phase was sustained in the chronic phase of TBI. Thus, a single IN dose of hMSC-EVs at 90 min post-TBI can ease TBI-induced declines in the BDNF-ERK-CREB signaling, hippocampal neurogenesis, and synapses.
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Tomar M, Beros J, Meloni B, Rodger J. Interactions between Guidance Cues and Neuronal Activity: Therapeutic Insights from Mouse Models. Int J Mol Sci 2023; 24:ijms24086966. [PMID: 37108129 PMCID: PMC10138948 DOI: 10.3390/ijms24086966] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 03/31/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
Topographic mapping of neural circuits is fundamental in shaping the structural and functional organization of brain regions. This developmentally important process is crucial not only for the representation of different sensory inputs but also for their integration. Disruption of topographic organization has been associated with several neurodevelopmental disorders. The aim of this review is to highlight the mechanisms involved in creating and refining such well-defined maps in the brain with a focus on the Eph and ephrin families of axon guidance cues. We first describe the transgenic models where ephrin-A expression has been manipulated to understand the role of these guidance cues in defining topography in various sensory systems. We further describe the behavioral consequences of lacking ephrin-A guidance cues in these animal models. These studies have given us unexpected insight into how neuronal activity is equally important in refining neural circuits in different brain regions. We conclude the review by discussing studies that have used treatments such as repetitive transcranial magnetic stimulation (rTMS) to manipulate activity in the brain to compensate for the lack of guidance cues in ephrin-knockout animal models. We describe how rTMS could have therapeutic relevance in neurodevelopmental disorders with disrupted brain organization.
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Affiliation(s)
- Maitri Tomar
- School of Biological Sciences, The University of Western Australia, Crawley, WA 6009, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia
| | - Jamie Beros
- School of Biological Sciences, The University of Western Australia, Crawley, WA 6009, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia
| | - Bruno Meloni
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia
- Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Crawley, WA 6009, Australia
- Department of Neurosurgery, Sir Charles Gairdner Hospital, QEII Medical Centre, Nedlands, WA 6009, Australia
| | - Jennifer Rodger
- School of Biological Sciences, The University of Western Australia, Crawley, WA 6009, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia
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Michinaga S, Hishinuma S, Koyama Y. Roles of Astrocytic Endothelin ET B Receptor in Traumatic Brain Injury. Cells 2023; 12:cells12050719. [PMID: 36899860 PMCID: PMC10000579 DOI: 10.3390/cells12050719] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 02/08/2023] [Accepted: 02/22/2023] [Indexed: 03/02/2023] Open
Abstract
Traumatic brain injury (TBI) is an intracranial injury caused by accidents, falls, or sports. The production of endothelins (ETs) is increased in the injured brain. ET receptors are classified into distinct types, including ETA receptor (ETA-R) and ETB receptor (ETB-R). ETB-R is highly expressed in reactive astrocytes and upregulated by TBI. Activation of astrocytic ETB-R promotes conversion to reactive astrocytes and the production of astrocyte-derived bioactive factors, including vascular permeability regulators and cytokines, which cause blood-brain barrier (BBB) disruption, brain edema, and neuroinflammation in the acute phase of TBI. ETB-R antagonists alleviate BBB disruption and brain edema in animal models of TBI. The activation of astrocytic ETB receptors also enhances the production of various neurotrophic factors. These astrocyte-derived neurotrophic factors promote the repair of the damaged nervous system in the recovery phase of patients with TBI. Thus, astrocytic ETB-R is expected to be a promising drug target for TBI in both the acute and recovery phases. This article reviews recent observations on the role of astrocytic ETB receptors in TBI.
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Affiliation(s)
- Shotaro Michinaga
- Department of Pharmacodynamics, Meiji Pharmaceutical University, 2-522-1 Noshio, Tokyo 204-8588, Japan
| | - Shigeru Hishinuma
- Department of Pharmacodynamics, Meiji Pharmaceutical University, 2-522-1 Noshio, Tokyo 204-8588, Japan
| | - Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558, Japan
- Correspondence: ; Tel.: +81-78-441-7572
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Zhang Z, Zhang X, Wu X, Zhang Y, Lu J, Li D. Sirt1 attenuates astrocyte activation via modulating Dnajb1 and chaperone-mediated autophagy after closed head injury. Cereb Cortex 2022; 32:5191-5205. [PMID: 35106540 DOI: 10.1093/cercor/bhac007] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/04/2022] [Accepted: 01/04/2022] [Indexed: 12/27/2022] Open
Abstract
Our previous study indicates that Silent information regulator 1 (Sirt1) is involved in macroautophagy by upregulating light chain 3 (LC3) expression in astrocyte to exert a neuroprotective effect. Chaperon-mediated autophagy (CMA), another form of autophagy, is also upregulated after brain injury. However, little is known about the role of Sirt1 in regulation of the CMA. In the present study, an in vivo model of closed head injury (CHI) and an in vitro model of primary cortical astrocyte stimulated with interleukin-1β were employed to mimic the astrocyte activation induced by traumatic brain injury. Lentivirus carrying target complementary DNA (cDNA) or short hairpin RNA (shRNA) sequence was used to overexpress Sirt1 or knockdown DnaJ heat shock protein family member B1 (Dnajb1) (a molecular chaperone). We found that Sirt1 overexpression ameliorated neurological deficits, reduced tissue loss, and attenuated astrocyte activation after CHI, which was reversed by Dnajb1-shRNA administration. The upregulation of CMA activity induced by CHI in vivo and in vitro was inhibited after Dnajb1 knockdown. Sirt1 potently promoted CMA activity via upregulating Dnajb1 expression. Mechanically, Sirt1 could interact with Dnajb1 and modulate the deacetylation and ubiquitination of Dnajb1. These findings collectively suggest that Sirt1 plays a protective role against astrocyte activation, which may be associated with the regulation of the CMA activity via modulating the deacetylation and ubiquitination of Dnajb1 after CHI.
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Affiliation(s)
- Zhuo Zhang
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
| | - Xu Zhang
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
| | - Xin Wu
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
| | - Yan Zhang
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
| | - Jie Lu
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
| | - Dan Li
- Department of Human Anatomy, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang 110122, Liaoning Province, P.R. China
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10
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Activation of NLRP3 Is Required for a Functional and Beneficial Microglia Response after Brain Trauma. Pharmaceutics 2022; 14:pharmaceutics14081550. [PMID: 35893807 PMCID: PMC9332196 DOI: 10.3390/pharmaceutics14081550] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 12/04/2022] Open
Abstract
Despite the numerous research studies on traumatic brain injury (TBI), many physiopathologic mechanisms remain unknown. TBI is a complex process, in which neuroinflammation and glial cells play an important role in exerting a functional immune and damage-repair response. The activation of the NLRP3 inflammasome is one of the first steps to initiate neuroinflammation and so its regulation is essential. Using a closed-head injury model and a pharmacological (MCC950; 3 mg/kg, pre- and post-injury) and genetical approach (NLRP3 knockout (KO) mice), we defined the transcriptional and behavioral profiles 24 h after TBI. Wild-type (WT) mice showed a strong pro-inflammatory response, with increased expression of inflammasome components, microglia and astrocytes markers, and cytokines. There was no difference in the IL1β production between WT and KO, nor compensatory mechanisms of other inflammasomes. However, some microglia and astrocyte markers were overexpressed in KO mice, resulting in an exacerbated cytokine expression. Pretreatment with MCC950 replicated the behavioral and blood-brain barrier results observed in KO mice and its administration 1 h after the lesion improved the damage. These findings highlight the importance of NLRP3 time-dependent activation and its role in the fine regulation of glial response.
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11
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Eyolfson E, Carr T, Fraunberger E, Khan A, Clark I, Mychasiuk R, Lohman AW. Repeated mild traumatic brain injuries in mice cause age- and sex-specific alterations in dendritic spine density. Exp Neurol 2022; 357:114172. [PMID: 35863503 DOI: 10.1016/j.expneurol.2022.114172] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/08/2022] [Accepted: 07/14/2022] [Indexed: 11/25/2022]
Abstract
Mild traumatic brain injuries (mTBI) plague the human population and their prevalence is increasing annually. More so, repeated mTBIs (RmTBI) are known to manifest and compound neurological deficits in vulnerable populations. Age at injury and sex are two important factors influencing RmTBI pathophysiology, but we continue to know little about the specific effects of RmTBI in youth and females. In this study, we directly quantified the effects of RmTBI on adolescent and adult, male and female mice, with a closed-head lateral impact model. We report age- and sex-specific neurobehavioural deficits in motor function and working memory, microglia responses to injury, and the subsequent changes in dendritic spine density in select brain regions. Specifically, RmTBI caused increased footslips in adult male mice as assessed in a beam walk assay and significantly reduced the time spent with a novel object in adolescent male and female mice. RmTBIs caused a significant reduction in microglia density in male mice in the motor cortex, but not female mice. Finally, RmTBI significantly reduced dendritic spine density in the agranular insular cortex (a region of the prefrontal cortex in mice) and increased dendritic spine density in the adolescent male motor cortex. Together, the data provided in this study sheds new light on the heterogeneity in RmTBI-induced behavioural, glial, and neuronal architecture changes dependent on age and sex.
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Affiliation(s)
- Eric Eyolfson
- Department of Psychology, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada.
| | - Thomas Carr
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Erik Fraunberger
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Asher Khan
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Isabel Clark
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Richelle Mychasiuk
- Department of Psychology, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada; Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia.
| | - Alexander W Lohman
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
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12
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The roles of Eph receptors, neuropilin-1, P2X7, and CD147 in COVID-19-associated neurodegenerative diseases: inflammasome and JaK inhibitors as potential promising therapies. Cell Mol Biol Lett 2022; 27:10. [PMID: 35109786 PMCID: PMC8809072 DOI: 10.1186/s11658-022-00311-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 01/14/2022] [Indexed: 12/20/2022] Open
Abstract
The novel coronavirus disease 2019 (COVID-19) pandemic has spread worldwide, and finding a safe therapeutic strategy and effective vaccine is critical to overcoming severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, elucidation of pathogenesis mechanisms, especially entry routes of SARS-CoV-2 may help propose antiviral drugs and novel vaccines. Several receptors have been demonstrated for the interaction of spike (S) protein of SARS-CoV-2 with host cells, including angiotensin-converting enzyme (ACE2), ephrin ligands and Eph receptors, neuropilin 1 (NRP-1), P2X7, and CD147. The expression of these entry receptors in the central nervous system (CNS) may make the CNS prone to SARS-CoV-2 invasion, leading to neurodegenerative diseases. The present review provides potential pathological mechanisms of SARS-CoV-2 infection in the CNS, including entry receptors and cytokines involved in neuroinflammatory conditions. Moreover, it explains several neurodegenerative disorders associated with COVID-19. Finally, we suggest inflammasome and JaK inhibitors as potential therapeutic strategies for neurodegenerative diseases.
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13
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Rais M, Lovelace JW, Shuai XS, Woodard W, Bishay S, Estrada L, Sharma AR, Nguy A, Kulinich A, Pirbhoy PS, Palacios AR, Nelson DL, Razak KA, Ethell IM. Functional consequences of postnatal interventions in a mouse model of Fragile X syndrome. Neurobiol Dis 2021; 162:105577. [PMID: 34871737 DOI: 10.1016/j.nbd.2021.105577] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 10/22/2021] [Accepted: 12/02/2021] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Fragile X syndrome (FXS) is a leading genetic cause of autism and intellectual disability with cortical hyperexcitability and sensory hypersensitivity attributed to loss and hypofunction of inhibitory parvalbumin-expressing (PV) cells. Our studies provide novel insights into the role of excitatory neurons in abnormal development of PV cells during a postnatal period of inhibitory circuit refinement. METHODS To achieve Fragile X mental retardation gene (Fmr1) deletion and re-expression in excitatory neurons during the postnatal day (P)14-P21 period, we generated CreCaMKIIa/Fmr1Flox/y (cOFF) and CreCaMKIIa/Fmr1FloxNeo/y (cON) mice, respectively. Cortical phenotypes were evaluated in adult mice using biochemical, cellular, clinically relevant electroencephalogram (EEG) and behavioral tests. RESULTS We found that similar to global Fmr1 KO mice, the density of PV-expressing cells, their activation, and sound-evoked gamma synchronization were impaired in cOFF mice, but the phenotypes were improved in cON mice. cOFF mice also showed enhanced cortical gelatinase activity and baseline EEG gamma power, which were reduced in cON mice. In addition, TrkB phosphorylation and PV levels were lower in cOFF mice, which also showed increased locomotor activity and anxiety-like behaviors. Remarkably, when FMRP levels were restored in only excitatory neurons during the P14-P21 period, TrkB phosphorylation and mouse behaviors were also improved. CONCLUSIONS These results indicate that postnatal deletion or re-expression of FMRP in excitatory neurons is sufficient to elicit or ameliorate structural and functional cortical deficits, and abnormal behaviors in mice, informing future studies about appropriate treatment windows and providing fundamental insights into the cellular mechanisms of cortical circuit dysfunction in FXS.
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Affiliation(s)
- Maham Rais
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Jonathan W Lovelace
- Department of Psychology, University of California Riverside, Riverside, CA 92521, USA
| | - Xinghao S Shuai
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Walker Woodard
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Steven Bishay
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Leo Estrada
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Ashwin R Sharma
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Austin Nguy
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Anna Kulinich
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Patricia S Pirbhoy
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | - Arnold R Palacios
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA
| | | | - Khaleel A Razak
- Department of Psychology, University of California Riverside, Riverside, CA 92521, USA; Neuroscience Graduate Program, University of California Riverside, Riverside, CA 92521, USA
| | - Iryna M Ethell
- Division of Biomedical Sciences and Biomedical Sciences Graduate Program, School of Medicine, University of California Riverside, Riverside, CA 92521, USA; Neuroscience Graduate Program, University of California Riverside, Riverside, CA 92521, USA.
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14
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Yuan M, Wu H. Astrocytes in the Traumatic Brain Injury: the Good and the Bad. Exp Neurol 2021; 348:113943. [PMID: 34863998 DOI: 10.1016/j.expneurol.2021.113943] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 11/08/2021] [Accepted: 11/29/2021] [Indexed: 12/21/2022]
Abstract
Astrocytes control many processes of the nervous system in health and disease, and respond to injury quickly. Astrocytes produce neuroprotective factors in the injured brain to clear cellular debris and to orchestrate neurorestorative processes that are beneficial for neurological recovery after traumatic brain injury (TBI). However, astrocytes also become dysregulated and produce cytotoxic mediators that hinder CNS repair by induction of neuronal dysfunction and cell death. Hence, we discuss the potential role of astrocytes in neuropathological processes such as neuroinflammation, neurogenesis, synaptogenesis and blood-brain barrier repair after TBI. Thus, an improved understanding of the dual role of astrocytes may advance our knowledge of post-brain injury recovery, and provide opportunities for the development of novel therapeutic strategies for TBI.
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Affiliation(s)
- Mengqi Yuan
- Institute of Neuroscience, Hengyang Medical College, University of South China, Hengyang, 421001, Hunan, China
| | - Haitao Wu
- Beijing Institute of Basic Medical Sciences, 100850 Beijing, China; Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226019, Jiangsu, China; Chinese Institute for Brain Research (CIBR), 102206 Beijing, China.
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15
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Rani A, Jakhmola S, Karnati S, Parmar HS, Chandra Jha H. Potential entry receptors for human γ-herpesvirus into epithelial cells: A plausible therapeutic target for viral infections. Tumour Virus Res 2021; 12:200227. [PMID: 34800753 PMCID: PMC8628264 DOI: 10.1016/j.tvr.2021.200227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/28/2021] [Accepted: 11/15/2021] [Indexed: 12/14/2022] Open
Abstract
Herpesviruses are ubiquitous viruses, specifically the Epstein Barr virus (EBV). EBV and Kaposi's sarcoma-associated herpesvirus (KSHV) establish their latency for a long period in B-cells and their reactivation instigates dreadful diseases from cancer to neurological modalities. The envelope glycoprotein of these viruses makes an attachment with several host receptors. For instance; glycoprotein 350/220, gp42, gHgL and gB of EBV establish an attachment with CD21, HLA-DR, Ephs, and other receptor molecules to hijack the B- and epithelial cell machinery. Ephs are reported recently as potent receptors for EBV entry into epithelial cells. Eph receptors play a role in the maintenance and control of various cellular processes including morphology, adhesion, proliferation, survival and differentiation. Alterations in the structure and expression of Eph and ephrin (Eph ligands) molecules is entangled with various pathologies including tumours and neurological complications. Along with Eph, integrins, NRP, NMHC are also key players in viral infections as they are possibly involved in viral transmission, replication and persistence. Contrarily, KSHV gH is known to interact with EphA2 and -A4 molecules, whereas in the case of EBV only EphA2 receptors are being reported to date. The ELEFN region of KSHV gH was involved in the interaction with EphA2, however, the interacting region of EBV gH is elusive. Further, the gHgL of KSHV and EBV form a complex with the EphA2 ligand-binding domain (LBD). Primarily by using gL both KSHV and EBV gHgL bind to the peripheral regions of LBD. In addition to γ-herpesviruses, several other viruses like Nipah virus, Cedar virus, Hepatitis C virus and Rhesus macaque rhadinovirus (RRV) also access the host cells via Eph receptors. Therefore, we summarise the possible roles of Eph and ephrins in virus-mediated infection and these molecules could serve as potential therapeutic targets. Crucial understanding of human γ-herpesviruses entry mechanism. Eph receptors relate to changed biomolecular profile upon EBV infection. EBV association with neurological disorders. Eph receptors could be an elegant drug for human γ-herpesviruses.
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Affiliation(s)
- Annu Rani
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India
| | - Shweta Jakhmola
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India
| | - Srikanth Karnati
- Department of Medical Cell Biology, Julius Maximilians University, Wuerzburg, Germany
| | - Hamendra Singh Parmar
- School of Biotechnology, Devi Ahilya University, Takshashila Campus, Khandwa Road, Indore, 452001, MP, India
| | - Hem Chandra Jha
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India.
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16
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Michinaga S, Koyama Y. Pathophysiological Responses and Roles of Astrocytes in Traumatic Brain Injury. Int J Mol Sci 2021; 22:ijms22126418. [PMID: 34203960 PMCID: PMC8232783 DOI: 10.3390/ijms22126418] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 12/14/2022] Open
Abstract
Traumatic brain injury (TBI) is immediate damage caused by a blow to the head resulting from traffic accidents, falls, and sporting activity, which causes death or serious disabilities in survivors. TBI induces multiple secondary injuries, including neuroinflammation, disruption of the blood–brain barrier (BBB), and brain edema. Despite these emergent conditions, current therapies for TBI are limited or insufficient in some cases. Although several candidate drugs exerted beneficial effects in TBI animal models, most of them failed to show significant effects in clinical trials. Multiple studies have suggested that astrocytes play a key role in the pathogenesis of TBI. Increased reactive astrocytes and astrocyte-derived factors are commonly observed in both TBI patients and experimental animal models. Astrocytes have beneficial and detrimental effects on TBI, including promotion and restriction of neurogenesis and synaptogenesis, acceleration and suppression of neuroinflammation, and disruption and repair of the BBB via multiple bioactive factors. Additionally, astrocytic aquaporin-4 is involved in the formation of cytotoxic edema. Thus, astrocytes are attractive targets for novel therapeutic drugs for TBI, although astrocyte-targeting drugs have not yet been developed. This article reviews recent observations of the roles of astrocytes and expected astrocyte-targeting drugs in TBI.
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Affiliation(s)
- Shotaro Michinaga
- Department of Pharmacodynamics, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan;
| | - Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558, Japan
- Correspondence: ; Tel.: +81-78-441-7572
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17
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Rosa JM, Farré-Alins V, Ortega MC, Navarrete M, Lopez-Rodriguez AB, Palomino-Antolín A, Fernández-López E, Vila-Del Sol V, Decouty C, Narros-Fernández P, Clemente D, Egea J. TLR4 pathway impairs synaptic number and cerebrovascular functions through astrocyte activation following traumatic brain injury. Br J Pharmacol 2021; 178:3395-3413. [PMID: 33830504 PMCID: PMC8453872 DOI: 10.1111/bph.15488] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 03/20/2021] [Accepted: 03/26/2021] [Indexed: 12/30/2022] Open
Abstract
Background and Purpose Activation of astrocytes contributes to synaptic remodelling, tissue repair and neuronal survival following traumatic brain injury (TBI). The mechanisms by which these cells interact to resident/infiltrated inflammatory cells to rewire neuronal networks and repair brain functions remain poorly understood. Here, we explored how TLR4‐induced astrocyte activation modified synapses and cerebrovascular integrity following TBI. Experimental Approach To determine how functional astrocyte alterations induced by activation of TLR4 pathway in inflammatory cells regulate synapses and neurovascular integrity after TBI, we used pharmacology, genetic approaches, live calcium imaging, immunofluorescence, flow cytometry, blood–brain barrier (BBB) integrity assessment and molecular and behavioural methods. Key Results Shortly after a TBI, there is a recruitment of excitable and reactive astrocytes mediated by TLR4 pathway activation with detrimental effects on post‐synaptic density‐95 (PSD‐95)/vesicular glutamate transporter 1 (VGLUT1) synaptic puncta, BBB integrity and neurological outcome. Pharmacological blockage of the TLR4 pathway with resatorvid (TAK‐242) partially reversed many of the observed effects. Synapses and BBB recovery after resatorvid administration were not observed in IP3R2−/− mice, indicating that effects of TLR4 inhibition depend on the subsequent astrocyte activation. In addition, TBI increased the astrocytic‐protein thrombospondin‐1 necessary to induce a synaptic recovery in a sub‐acute phase. Conclusions and Implications Our data demonstrate that TLR4‐mediated signalling, most probably through microglia and/or infiltrated monocyte–astrocyte communication, plays a crucial role in the TBI pathophysiology and that its inhibition prevents synaptic loss and BBB damage accelerating tissue recovery/repair, which might represent a therapeutic potential in CNS injuries and disorders.
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Affiliation(s)
- Juliana M Rosa
- Experimental Neurophysiology and Neuronal Circuits Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha, SESCAM, Toledo, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - Víctor Farré-Alins
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - María Cristina Ortega
- Neuroinmune-Repair Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha, SESCAM, Toledo, Spain
| | - Marta Navarrete
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Ana Belen Lopez-Rodriguez
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - Alejandra Palomino-Antolín
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - Elena Fernández-López
- Experimental Neurophysiology and Neuronal Circuits Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha, SESCAM, Toledo, Spain
| | - Virginia Vila-Del Sol
- Flow Cytometry Service, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha, SESCAM, Toledo, Spain
| | - Céline Decouty
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - Paloma Narros-Fernández
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
| | - Diego Clemente
- Neuroinmune-Repair Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha, SESCAM, Toledo, Spain
| | - Javier Egea
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.,Research Unit, Hospital Santa Cristina, Instituto de Investigación Sanitaria Princesa (IIS-IP), Hospital Universitario de la Princesa, Madrid, Spain
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18
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Tan CX, Eroglu C. Cell adhesion molecules regulating astrocyte-neuron interactions. Curr Opin Neurobiol 2021; 69:170-177. [PMID: 33957433 DOI: 10.1016/j.conb.2021.03.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/23/2021] [Accepted: 03/24/2021] [Indexed: 12/15/2022]
Abstract
A tripartite synapse comprises a neuronal presynaptic axon and a postsynaptic dendrite, which are closely ensheathed by a perisynaptic astrocyte process. Through their structural and functional association with thousands of neuronal synapses, astrocytes regulate synapse formation and function. Recent work revealed a diverse range of cell adhesion-based mechanisms that mediate astrocyte-synapse interactions at tripartite synapses. Here, we will review some of these findings unveiling a highly dynamic bidirectional signaling between astrocytes and synapses, which orchestrates astrocyte morphological maturation and synapse development. Moreover, we will discuss the roles of these newly discovered molecular pathways in brain physiology and function both in health and disease.
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Affiliation(s)
- Christabel X Tan
- Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Cagla Eroglu
- Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA; Department of Neurobiology, Duke University Medical Center, Durham, NC, 27710, USA; Duke Institute for Brain Sciences, Durham, NC, 27710, USA; Regeneration Next Initiative, Duke University, Durham, NC, 27710, USA.
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19
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Jamjoom AAB, Rhodes J, Andrews PJD, Grant SGN. The synapse in traumatic brain injury. Brain 2021; 144:18-31. [PMID: 33186462 PMCID: PMC7880663 DOI: 10.1093/brain/awaa321] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
Traumatic brain injury (TBI) is a leading cause of death and disability worldwide and is a risk factor for dementia later in life. Research into the pathophysiology of TBI has focused on the impact of injury on the neuron. However, recent advances have shown that TBI has a major impact on synapse structure and function through a combination of the immediate mechanical insult and the ensuing secondary injury processes, leading to synapse loss. In this review, we highlight the role of the synapse in TBI pathophysiology with a focus on the confluence of multiple secondary injury processes including excitotoxicity, inflammation and oxidative stress. The primary insult triggers a cascade of events in each of these secondary processes and we discuss the complex interplay that occurs at the synapse. We also examine how the synapse is impacted by traumatic axonal injury and the role it may play in the spread of tau after TBI. We propose that astrocytes play a crucial role by mediating both synapse loss and recovery. Finally, we highlight recent developments in the field including synapse molecular imaging, fluid biomarkers and therapeutics. In particular, we discuss advances in our understanding of synapse diversity and suggest that the new technology of synaptome mapping may prove useful in identifying synapses that are vulnerable or resistant to TBI.
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Affiliation(s)
- Aimun A B Jamjoom
- Centre for Clinical Brain Sciences, Chancellor's Building, Edinburgh BioQuarter, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Jonathan Rhodes
- Anaesthesia, Critical Care and Pain Medicine, University of Edinburgh, Edinburgh EH16 4SA, UK
| | - Peter J D Andrews
- Anaesthesia, Critical Care and Pain Medicine, University of Edinburgh, Edinburgh EH16 4SA, UK
| | - Seth G N Grant
- Centre for Clinical Brain Sciences, Chancellor's Building, Edinburgh BioQuarter, University of Edinburgh, Edinburgh EH16 4SB, UK
- Simons Initiative for the Developing Brain (SIDB), Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
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20
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Koyama Y, Tsuboi S, Mizogui F. Endothelin-1 decreases the expression of Ephrin-A and B subtypes in cultured rat astrocytes through ET B receptors. Neurosci Lett 2021; 741:135393. [PMID: 33279571 DOI: 10.1016/j.neulet.2020.135393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/08/2020] [Accepted: 09/14/2020] [Indexed: 11/24/2022]
Abstract
Ephrin family proteins are cell surface molecules that regulate several cellular functions through cell-cell interactions. During nervous tissue repair after injury, the expression of ephrin subtypes in astrocytes is altered, affecting the axonal elongation and migration of neuronal precursors. However, the mechanism regulating the expression of ephrin subtypes in astrocytes has not been investigated. Herein, we studied the effects of endothelin-1 (ET-1) on the expression of ephrin subtypes in cultured rat astrocytes. Our results showed that ET-1 (100 nM) treatment for 1-24 h reduced the expression of ephrin-A2, -A4, -B2, and -B3 mRNA and protein in astrocytes, whereas the expression of ephrin-A1, -A3, -A5, and -B1 mRNA were not affected. Sarafotoxin S6c, a selective ETB receptor agonist, decreased the expression of ephrin-A2, -A4, -B2, and -B3 in cultured astrocytes. The decrease in ephrin-A2, -A4, -B2, and -B3 expression by ET-1 treatment was reduced in the presence of BQ788, an ETB receptor antagonist, while FR139317, an ETA receptor antagonist, had no effects. These results suggest that ET-1 is a signaling molecule that downregulates ephrin-A2, -A4, -B2, and -B3 expression in astrocytes.
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Affiliation(s)
- Yutaka Koyama
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan.
| | - Sayaka Tsuboi
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan
| | - Fuka Mizogui
- Laboratory of Pharmacology, Kobe Pharmaceutical University, 4-19-1 Motoyama-Kita Higashinada, Kobe 668-8558 Japan
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21
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Wu J, Li H, He J, Tian X, Luo S, Li J, Li W, Zhong J, Zhang H, Huang Z, Sun X, Jiang T. Downregulation of microRNA-9-5p promotes synaptic remodeling in the chronic phase after traumatic brain injury. Cell Death Dis 2021; 12:9. [PMID: 33414448 PMCID: PMC7790831 DOI: 10.1038/s41419-020-03329-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 01/29/2023]
Abstract
The level of microRNA-9-5p (miRNA-9-5p) in brain tissues is significantly changed in the chronic phase after traumatic brain injury (TBI). However, the effect of miRNA-9-5p on brain function after TBI has not been elucidated. In this study, we used a controlled cortical impact (CCI) model to induce TBI in Sprague-Dawley rats. Brain microvascular endothelial cells (BMECs), astrocytes, and neurons were extracted from immature Sprague-Dawley rats and cocultured to reconstruct the neurovascular unit (NVU) in vitro. The results showed that downregulation of miRNA-9-5p in the chronic phase contributed to neurological function recovery by promoting astrocyte proliferation and increasing the release of astrocyte-derived neurotrophic factors around injured brain tissues after TBI. A dual-luciferase reporter assay validated that miRNA-9-5p was a post-transcriptional modulator of thrombospondin 2 (Thbs-2), and downregulation of miRNA-9-5p promoted Thbs-2 expression in astrocytes. Furthermore, we verified that Thbs-2 can promote Notch pathway activation by directly binding to Jagged and Notch. Through in vitro experiments, we found that the expression of synaptic proteins and the number of synaptic bodies were increased in neurons in the NVU, which was constructed using astrocytes pretreated with miRNA-9-5p inhibitor. Moreover, we also found that downregulation of miRNA-9-5p promoted Thbs-2 expression in astrocytes, which activated the Notch/cylindromatosis/transforming growth factor-β-activated kinase 1 pathway in neurons and promoted the expression of synaptic proteins, including post-synaptic density protein 95 and synaptotagmin. Based on these results, miRNA-9-5p may be a new promising prognostic marker and treatment target for TBI.
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Affiliation(s)
- Jingchuan Wu
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China ,Department of Neurosurgery, General Hospital of The YangTze River Shipping, Wuhan Brain Hospital, Wuhan, Hubei 430014 China
| | - Hui Li
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Junchi He
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Xiaocui Tian
- grid.203458.80000 0000 8653 0555College of Pharmacy, Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing Medical University, Chongqing, Yuzhong 400016 China
| | - Shuilian Luo
- grid.413247.7Department of Ultrasound, Zhongnan Hospital of WuHan University, Wuhan, 430071 China
| | - Jiankang Li
- grid.35030.350000 0004 1792 6846Dept of Computer Science, City University of Hong Kong, 83 Tat Chee Ave, Kowloon Hong Kong, China
| | - Wei Li
- grid.410726.60000 0004 1797 8419BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083 China
| | - Jianjun Zhong
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Hongrong Zhang
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Zhijian Huang
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Xiaochuan Sun
- grid.452206.7Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016 China
| | - Tao Jiang
- grid.24696.3f0000 0004 0369 153XDepartment of Neurosurgery, Beijing TianTan Hospital, Capital Medical University, Beijing, 100050 China ,grid.24696.3f0000 0004 0369 153XBeijing Neurosurgical Institute, Capital Medical University, Beijing, 100050 China ,grid.411617.40000 0004 0642 1244China National Clinical Research Center for Neurological diseases, Beijing, China
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22
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Sakai K, Takata F, Yamanaka G, Yasunaga M, Hashiguchi K, Tominaga K, Itoh K, Kataoka Y, Yamauchi A, Dohgu S. Reactive pericytes in early phase are involved in glial activation and late-onset hypersusceptibility to pilocarpine-induced seizures in traumatic brain injury model mice. J Pharmacol Sci 2021; 145:155-165. [PMID: 33357774 DOI: 10.1016/j.jphs.2020.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/27/2020] [Accepted: 11/20/2020] [Indexed: 02/07/2023] Open
Abstract
In this study, among neurovascular unit (NVU) cells, we focused on pericyte reactivity in mice subjected to controlled cortical impact (CCI) to understand how traumatic brain injury (TBI) causes uncoordinated crosstalk in the NVU and alters neuronal activity. Histological analyses of brain pericytes, microglia and astrocytes were performed for up to 28 days after CCI in the injured ipsilateral hippocampus. To evaluate altered neuronal activity caused by CCI, we measured seizure susceptibility to a sub-threshold dose of pilocarpine on postoperative day 7, 14, 21 and 28. Platelet-derived growth factor receptor (PDGFR) β immunoreactivity in pericytes significantly increased from 1 h to 4 days after CCI. The expression of Iba1 and GFAP, as markers of microglia and astrocytes, respectively, increased from 4 to 28 days after CCI. The severity of seizure induced by pilocarpine gradually increased, becoming significant at 28 days after CCI. Then, we treated CCI mice with an inhibitor of PDGFR signaling, imatinib, during the postoperative day 0-4 period. Imatinib lowered seizure susceptibility to pilocarpine and suppressed microglial activation in the injured hippocampus at postoperative day 28. These findings indicate that brain pericytes with rapidly increased PDGFRβ expression may drive TBI-induced dysregulation of NVU function and brain hyperexcitability.
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Affiliation(s)
- Kenta Sakai
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Fuyuko Takata
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan.
| | - Gaku Yamanaka
- Department of Pediatrics and Adolescent Medicine, Tokyo Medical University, Tokyo, 160-0023, Japan
| | - Miho Yasunaga
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Kana Hashiguchi
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Kazuki Tominaga
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Kouichi Itoh
- Laboratory for Pharmacotherapy and Experimental Neurology, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Kagawa, 769-2193, Japan
| | - Yasufumi Kataoka
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Atsushi Yamauchi
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
| | - Shinya Dohgu
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180, Japan
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Fossati G, Matteoli M, Menna E. Astrocytic Factors Controlling Synaptogenesis: A Team Play. Cells 2020; 9:E2173. [PMID: 32993090 PMCID: PMC7600026 DOI: 10.3390/cells9102173] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 12/14/2022] Open
Abstract
Astrocytes are essential players in brain circuit development and homeostasis, controlling many aspects of synapse formation, function, plasticity and elimination both during development and adulthood. Accordingly, alterations in astrocyte morphogenesis and physiology may severely affect proper brain development, causing neurological or neuropsychiatric conditions. Recent findings revealed a huge astrocyte heterogeneity among different brain areas, which is likely at the foundation of the different synaptogenic potential of these cells in selected brain regions. This review highlights recent findings on novel mechanisms that regulate astrocyte-mediated synaptogenesis during development, and the control of synapse number in the critical period or upon synaptic plasticity.
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Affiliation(s)
- Giuliana Fossati
- Humanitas Clinical and Research Center—IRCCS—NeuroCenter, via Manzoni 56, 20089 Rozzano, Milan, Italy; (G.F.); (M.M.)
| | - Michela Matteoli
- Humanitas Clinical and Research Center—IRCCS—NeuroCenter, via Manzoni 56, 20089 Rozzano, Milan, Italy; (G.F.); (M.M.)
- CNR, Department of Biomedical Sciences, Institute of Neuroscience—URT Humanitas, via Manzoni 56, 20089 Rozzano, Italy
| | - Elisabetta Menna
- Humanitas Clinical and Research Center—IRCCS—NeuroCenter, via Manzoni 56, 20089 Rozzano, Milan, Italy; (G.F.); (M.M.)
- CNR, Department of Biomedical Sciences, Institute of Neuroscience—URT Humanitas, via Manzoni 56, 20089 Rozzano, Italy
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24
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Elibol B, Beker M, Jakubowska-Dogru E, Kilic U. Fetal alcohol and maternal stress modify the expression of proteins controlling postnatal development of the male rat hippocampus. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2020; 46:718-730. [PMID: 32915069 DOI: 10.1080/00952990.2020.1780601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background: Developing brains can partially get over prenatal alcohol exposure-related detrimental conditions by activating some mechanisms involved in survival. Objectives: This study aimed to shed light on the molecular correlates of compensatory mechanisms by examining temporal profiles in the expression of proteins controlling postnatal development in the rat hippocampus prenatally exposed to intubation stress/ethanol. Methods: Male pups were randomly assigned to age subgroups (n = 21/age) which were sacrificed on postnatal day (PD)1, PD10, PD30, and PD60. Ethanol (6 g/kg/day) were intragastrically intubated to the dams throughout 7-21 gestation days. The expression of neurogenesis and angiogenesis markers, extracellular matrix proteins, and growth-promoting ligands were examined by western blot. Results: The most rapid increase in the index of neuronal maturation was noted between PD10-PD30 (p < .05). Prenatal stress caused a decrease of neurogenesis markers at birth and an increase of their expressions at PD10 and PD30 to reach control levels (p < .001). The impact of fetal-alcohol was observed as a decrease in the expression of synaptic plasticity protein versican at birth (p < .001), an increase in the synaptic repulsion protein ephrin-B2 at PD10 (p < .001), and a decrease in the maturation of BDNF at PD30 (p < .001) with a decrease in the mature neuron markers at PD30 (p < .001) and PD60 (p = .005) which were compensated with upregulation of angiogenesis and increasing brevican expression, a neuronal maturation protein (p < .001). Conclusion: These data provide in vivo evidence for the potential therapeutic factors related to neurogenesis, angiogenesis, and neurite remodeling which may tolerate the alcohol/stress dependent teratogenicity in the developing hippocampus.
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Affiliation(s)
- Birsen Elibol
- Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University , Istanbul, Turkey
| | - Merve Beker
- Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University , Istanbul, Turkey.,Department of Medical Biology, School of Medicine, University of Health Sciences , Istanbul, Turkey
| | - Ewa Jakubowska-Dogru
- Department of Biological Sciences, Faculty of Science and Arts, Middle East Technical University , Ankara, Turkey
| | - Ulkan Kilic
- Department of Medical Biology, School of Medicine, University of Health Sciences , Istanbul, Turkey
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25
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Stevenson R, Samokhina E, Rossetti I, Morley JW, Buskila Y. Neuromodulation of Glial Function During Neurodegeneration. Front Cell Neurosci 2020; 14:278. [PMID: 32973460 PMCID: PMC7473408 DOI: 10.3389/fncel.2020.00278] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022] Open
Abstract
Glia, a non-excitable cell type once considered merely as the connective tissue between neurons, is nowadays acknowledged for its essential contribution to multiple physiological processes including learning, memory formation, excitability, synaptic plasticity, ion homeostasis, and energy metabolism. Moreover, as glia are key players in the brain immune system and provide structural and nutritional support for neurons, they are intimately involved in multiple neurological disorders. Recent advances have demonstrated that glial cells, specifically microglia and astroglia, are involved in several neurodegenerative diseases including Amyotrophic lateral sclerosis (ALS), Epilepsy, Parkinson's disease (PD), Alzheimer's disease (AD), and frontotemporal dementia (FTD). While there is compelling evidence for glial modulation of synaptic formation and regulation that affect neuronal signal processing and activity, in this manuscript we will review recent findings on neuronal activity that affect glial function, specifically during neurodegenerative disorders. We will discuss the nature of each glial malfunction, its specificity to each disorder, overall contribution to the disease progression and assess its potential as a future therapeutic target.
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Affiliation(s)
- Rebecca Stevenson
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Evgeniia Samokhina
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Ilaria Rossetti
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - John W. Morley
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Yossi Buskila
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
- International Centre for Neuromorphic Systems, The MARCS Institute for Brain, Behaviour and Development, Penrith, NSW, Australia
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26
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Hennes M, Lombaert N, Wahis J, Van den Haute C, Holt MG, Arckens L. Astrocytes shape the plastic response of adult cortical neurons to vision loss. Glia 2020; 68:2102-2118. [DOI: 10.1002/glia.23830] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 03/10/2020] [Accepted: 03/13/2020] [Indexed: 12/26/2022]
Affiliation(s)
- Maroussia Hennes
- Department of BiologyKU Leuven Leuven Belgium
- VIB KU Leuven Center for Brain & Disease Research Leuven Belgium
- Leuven Brain Institute Leuven Belgium
| | | | - Jérôme Wahis
- VIB KU Leuven Center for Brain & Disease Research Leuven Belgium
- Leuven Brain Institute Leuven Belgium
- Department of NeurosciencesKU Leuven Leuven Belgium
| | - Chris Van den Haute
- Department of Biomedical SciencesKU Leuven Leuven Belgium
- KU Leuven Viral Vector Core Leuven Belgium
| | - Matthew G. Holt
- VIB KU Leuven Center for Brain & Disease Research Leuven Belgium
- Leuven Brain Institute Leuven Belgium
- Department of NeurosciencesKU Leuven Leuven Belgium
| | - Lutgarde Arckens
- Department of BiologyKU Leuven Leuven Belgium
- Leuven Brain Institute Leuven Belgium
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27
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Nguyen AQ, Koeppen J, Woodruff S, Mina K, Figueroa Z, Ethell IM. Astrocytic Ephrin-B1 Controls Synapse Formation in the Hippocampus During Learning and Memory. Front Synaptic Neurosci 2020; 12:10. [PMID: 32256333 PMCID: PMC7092624 DOI: 10.3389/fnsyn.2020.00010] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 02/24/2020] [Indexed: 01/20/2023] Open
Abstract
Astrocytes play a fundamental role in synapse formation, pruning, and plasticity, which are associated with learning and memory. However, the role of astrocytes in learning and memory is still largely unknown. Our previous study showed that astrocyte-specific ephrin-B1 knock-out (KO) enhanced but ephrin-B1 overexpression (OE) in hippocampal astrocytes impaired contextual memory recall following fear conditioning. The goal of this study was to understand the mechanism by which astrocytic ephrin-B1 influences learning; specifically, learning-induced remodeling of synapses and dendritic spines in CA1 hippocampus using fear-conditioning paradigm. While we found a higher dendritic spine density and clustering on c-Fos-positive (+) neurons activated during contextual memory recall in both wild-type (WT) and KO mice, overall spine density and mEPSC amplitude were increased in CA1 neurons of KO compared to WT. In contrast, ephrin-B1 OE in hippocampal astrocytes impaired dendritic spine formation and clustering, specifically on c-Fos(+) neurons, coinciding with an overall decrease in vGlut1/PSD95 co-localization. Although astrocytic ephrin-B1 influenced learning-induced spine formation, the changes in astrocytic ephrin-B1 levels did not affect spine enlargement as no genotype differences in spine volume were observed between trained WT, KO, and OE groups. Our results suggest that a reduced formation of new spines rather than spine maturation in activated CA1 hippocampal neurons is most likely responsible for impaired contextual learning in OE mice due to abundantly high ephrin-B1 levels in astrocytes. The ability of astrocytic ephrin-B1 to negatively influence new spine formation during learning can potentially regulate new synapse formation at specific dendritic domains and underlie memory encoding.
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Affiliation(s)
- Amanda Q. Nguyen
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States
| | - Jordan Koeppen
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Cell, Molecular, and Developmental Biology Graduate Program, University of California, Riverside, Riverside, CA, United States
| | - Simone Woodruff
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Karen Mina
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Zoe Figueroa
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
| | - Iryna M. Ethell
- Division of Biomedical Sciences, University of California Riverside School of Medicine, Riverside, CA, United States
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States
- Cell, Molecular, and Developmental Biology Graduate Program, University of California, Riverside, Riverside, CA, United States
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28
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Garcia-Diaz B, Bachelin C, Coulpier F, Gerschenfeld G, Deboux C, Zujovic V, Charnay P, Topilko P, Baron-Van Evercooren A. Blood vessels guide Schwann cell migration in the adult demyelinated CNS through Eph/ephrin signaling. Acta Neuropathol 2019; 138:457-476. [PMID: 31011859 PMCID: PMC6689289 DOI: 10.1007/s00401-019-02011-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/27/2019] [Accepted: 04/07/2019] [Indexed: 12/30/2022]
Abstract
Schwann cells (SC) enter the central nervous system (CNS) in pathophysiological conditions. However, how SC invade the CNS to remyelinate central axons remains undetermined. We studied SC migratory behavior ex vivo and in vivo after exogenous transplantation in the demyelinated spinal cord. The data highlight for the first time that SC migrate preferentially along blood vessels in perivascular extracellular matrix (ECM), avoiding CNS myelin. We demonstrate in vitro and in vivo that this migration route occurs by virtue of a dual mode of action of Eph/ephrin signaling. Indeed, EphrinB3, enriched in myelin, interacts with SC Eph receptors, to drive SC away from CNS myelin, and triggers their preferential adhesion to ECM components, such as fibronectin via integrinβ1 interactions. This complex interplay enhances SC migration along the blood vessel network and together with lesion-induced vascular remodeling facilitates their timely invasion of the lesion site. These novel findings elucidate the mechanism by which SC invade and contribute to spinal cord repair.
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29
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Teng S, Palmieri A, Maita I, Zheng C, Das G, Park J, Zhou R, Alder J, Thakker-Varia S. Inhibition of EphA/Ephrin-A signaling using genetic and pharmacologic approaches improves recovery following traumatic brain injury in mice. Brain Inj 2019; 33:1385-1401. [DOI: 10.1080/02699052.2019.1641622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Shavonne Teng
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Alicia Palmieri
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Isabella Maita
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Cynthia Zheng
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Gitanjali Das
- Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey, USA
| | - Juyeon Park
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Renping Zhou
- Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey, USA
| | - Janet Alder
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
| | - Smita Thakker-Varia
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, USA
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30
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Pericyte loss leads to circulatory failure and pleiotrophin depletion causing neuron loss. Nat Neurosci 2019; 22:1089-1098. [PMID: 31235908 PMCID: PMC6668719 DOI: 10.1038/s41593-019-0434-z] [Citation(s) in RCA: 210] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/22/2019] [Indexed: 12/11/2022]
Abstract
Pericytes are positioned between brain capillary endothelial cells, astrocytes and neurons. They degenerate in multiple neurological disorders. However, their role in the pathogenesis of these disorders remains debatable. Here we generate an inducible pericyte-specific Cre line and cross pericyte-specific Cre mice with iDTR mice carrying Cre-dependent human diphtheria toxin receptor. After pericyte ablation with diphtheria toxin, mice showed acute blood-brain barrier breakdown, severe loss of blood flow, and a rapid neuron loss that was associated with loss of pericyte-derived pleiotrophin (PTN), a neurotrophic growth factor. Intracerebroventricular PTN infusions prevented neuron loss in pericyte-ablated mice despite persistent circulatory changes. Silencing of pericyte-derived Ptn rendered neurons vulnerable to ischemic and excitotoxic injury. Our data demonstrate a rapid neurodegeneration cascade that links pericyte loss to acute circulatory collapse and loss of PTN neurotrophic support. These findings may have implications for the pathogenesis and treatment of neurological disorders that are associated with pericyte loss and/or neurovascular dysfunction.
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31
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Siebold L, Obenaus A, Goyal R. Criteria to define mild, moderate, and severe traumatic brain injury in the mouse controlled cortical impact model. Exp Neurol 2018; 310:48-57. [DOI: 10.1016/j.expneurol.2018.07.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 06/05/2018] [Accepted: 07/11/2018] [Indexed: 10/28/2022]
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32
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Mansilla A, Jordán-Álvarez S, Santana E, Jarabo P, Casas-Tintó S, Ferrús A. Molecular mechanisms that change synapse number. J Neurogenet 2018; 32:155-170. [DOI: 10.1080/01677063.2018.1506781] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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33
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Henderson NT, Dalva MB. EphBs and ephrin-Bs: Trans-synaptic organizers of synapse development and function. Mol Cell Neurosci 2018; 91:108-121. [PMID: 30031105 PMCID: PMC6159941 DOI: 10.1016/j.mcn.2018.07.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 12/31/2022] Open
Abstract
Synapses are specialized cell-cell junctions that underlie the function of neural circuits by mediating communication between neurons. Both the formation and function of synapses require tight coordination of signaling between pre- and post-synaptic neurons. Trans-synaptic organizing molecules are important mediators of such signaling. Here we discuss how the EphB and ephrin-B families of trans-synaptic organizing proteins direct synapse formation during early development and regulate synaptic function and plasticity at mature synapses. Finally, we highlight recent evidence linking the synaptic organizing role of EphBs and ephrin-Bs to diseases of maladaptive synaptic function and plasticity.
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Affiliation(s)
- Nathan T Henderson
- The Jefferson Synaptic Biology Center, Department of Neuroscience, The Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College at Thomas Jefferson University, Jefferson Hospital for Neuroscience, Suite 463, 900 Walnut St., Philadelphia, PA 19107, United States
| | - Matthew B Dalva
- The Jefferson Synaptic Biology Center, Department of Neuroscience, The Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College at Thomas Jefferson University, Jefferson Hospital for Neuroscience, Suite 463, 900 Walnut St., Philadelphia, PA 19107, United States.
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34
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Specific deletion connexin43 in astrocyte ameliorates cognitive dysfunction in APP/PS1 mice. Life Sci 2018; 208:175-191. [PMID: 30031059 DOI: 10.1016/j.lfs.2018.07.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/15/2018] [Accepted: 07/18/2018] [Indexed: 11/22/2022]
Abstract
Emerging data indicate an important role for connexin43 (Cx43) in cognitive function, but there is a lack of direct evidence of the role of astroglial Cx43 in cognitive dysfunction in Alzheimer's disease (AD). Here we evaluated the expression pattern of Cx43 in AD and found progressive upregulation of the mRNA and protein levels of Cx43. Subsequently, we generated an astroglial Cx43 knockout (KO) AD mouse model by crossbreeding Gfap (glial fibrillary acidic protein)-Cx43 KO mice with APP/PS1 mice. Then we assessed the cognitive function of 12-month-old APP (amyloid precursor protein)/PS1 (presenilin 1)/Gfap-Cx43 KO mice, which demonstrated that the deletion of astroglial Cx43 significantly ameliorated cognitive dysfunction. To further investigate the underlying mechanisms, we evaluated amyloid plaque formation, astrogliosis, and synaptic function. The number and area of amyloid plaques were not altered, but GFAP expression was significantly decreased and the number of synapses was markedly upregulated. These results suggest that deletion of astroglial Cx43 in APP/PS1 mice did not affect the formation of amyloid plaques but depressed astrogliosis and upregulated synaptic function. Moreover, levels of critical modulators of astroglial activation were also notably reduced, but those of pro- and anti-inflammatory cytokines were not altered. Furthermore, Cx43 regulation of postsynaptic elements targets mainly NMDAR (N-methyl-d-aspartate). In addition, the prevention of AD pathology was reversed by Cx43 re-expression. In sum, specific deletion of astroglial Cx43 in APP/PS1 mice improved cognitive dysfunction by decreasing astrogliosis and increasing synaptic function without affecting amyloid plaque formation or the inflammatory response.
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Functional Consequences of Synapse Remodeling Following Astrocyte-Specific Regulation of Ephrin-B1 in the Adult Hippocampus. J Neurosci 2018; 38:5710-5726. [PMID: 29793972 DOI: 10.1523/jneurosci.3618-17.2018] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 05/13/2018] [Accepted: 05/15/2018] [Indexed: 01/22/2023] Open
Abstract
Astrocyte-derived factors can control synapse formation and functions, making astrocytes an attractive target for regulating neuronal circuits and associated behaviors. Abnormal astrocyte-neuronal interactions are also implicated in neurodevelopmental disorders and neurodegenerative diseases associated with impaired learning and memory. However, little is known about astrocyte-mediated mechanisms that regulate learning and memory. Here, we propose astrocytic ephrin-B1 as a regulator of synaptogenesis in adult hippocampus and mouse learning behaviors. We found that astrocyte-specific ablation of ephrin-B1 in male mice triggers an increase in the density of immature dendritic spines and excitatory synaptic sites in the adult CA1 hippocampus. However, the prevalence of immature dendritic spines is associated with decreased evoked postsynaptic firing responses in CA1 pyramidal neurons, suggesting impaired maturation of these newly formed and potentially silent synapses or increased excitatory drive on the inhibitory neurons resulting in the overall decreased postsynaptic firing. Nevertheless, astrocyte-specific ephrin-B1 knock-out male mice exhibit normal acquisition of fear memory but enhanced contextual fear memory recall. In contrast, overexpression of astrocytic ephrin-B1 in the adult CA1 hippocampus leads to the loss of dendritic spines, reduced excitatory input, and impaired contextual memory retention. Our results suggest that astrocytic ephrin-B1 may compete with neuronal ephrin-B1 and mediate excitatory synapse elimination through its interactions with neuronal EphB receptors. Indeed, a deletion of neuronal EphB receptors impairs the ability of astrocytes expressing functional ephrin-B1 to engulf synaptosomes in vitro Our findings demonstrate that astrocytic ephrin-B1 regulates long-term contextual memory by restricting new synapse formation in the adult hippocampus.SIGNIFICANCE STATEMENT These studies address a gap in our knowledge of astrocyte-mediated regulation of learning and memory by unveiling a new role for ephrin-B1 in astrocytes and elucidating new mechanisms by which astrocytes regulate learning. Our studies explore the mechanisms underlying astrocyte regulation of hippocampal circuit remodeling during learning using new genetic tools that target ephrin-B signaling in astrocytes in vivo On a subcellular level, astrocytic ephrin-B1 may compete with neuronal ephrin-B1 and trigger astrocyte-mediated elimination of EphB receptor-containing synapses. Given the role EphB receptors play in neurodevelopmental disorders and neurodegenerative diseases, these findings establish a foundation for future studies of astrocyte-mediated synaptogenesis in clinically relevant conditions that can help to guide the development of clinical applications for a variety of neurological disorders.
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Yang JS, Wei HX, Chen PP, Wu G. Roles of Eph/ephrin bidirectional signaling in central nervous system injury and recovery. Exp Ther Med 2018. [PMID: 29456630 DOI: 10.3892/etm.2018.5702.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Multiple cellular components are involved in the complex pathological process following central nervous system (CNS) injury, including neurons, glial cells and endothelial cells. Previous studies and neurotherapeutic clinical trials have assessed the molecular mechanisms that underlie neuronal cell death following CNS injury. However, this approach has largely failed to reduce CNS damage or improve the functional recovery of patients. Erythropoietin-producing human hepatocellular (Eph) receptors and ephrin ligands have attracted considerable attention since their discovery, due to their extensive distribution and unique bidirectional signaling between astrocytes and neurons. Previous studies have investigated the roles of Eph/ephrin bidirectional signaling in the developing central nervous system. It was determined that Eph/ephrin bidirectional signaling is expressed in various CNS regions and cell types, and that it serves diverse roles in the adult CNS. In the present review, the roles of Eph/ephrin bidirectional signaling in CNS injuries are assessed.
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Affiliation(s)
- Jin-Shan Yang
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Hui-Xing Wei
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Ping-Ping Chen
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Gang Wu
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
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37
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Hillen AEJ, Burbach JPH, Hol EM. Cell adhesion and matricellular support by astrocytes of the tripartite synapse. Prog Neurobiol 2018; 165-167:66-86. [PMID: 29444459 DOI: 10.1016/j.pneurobio.2018.02.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/25/2017] [Accepted: 02/07/2018] [Indexed: 12/18/2022]
Abstract
Astrocytes contribute to the formation, function, and plasticity of synapses. Their processes enwrap the neuronal components of the tripartite synapse, and due to this close interaction they are perfectly positioned to modulate neuronal communication. The interaction between astrocytes and synapses is facilitated by cell adhesion molecules and matricellular proteins, which have been implicated in the formation and functioning of tripartite synapses. The importance of such neuron-astrocyte integration at the synapse is underscored by the emerging role of astrocyte dysfunction in synaptic pathologies such as autism and schizophrenia. Here we review astrocyte-expressed cell adhesion molecules and matricellular molecules that play a role in integration of neurons and astrocytes within the tripartite synapse.
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Affiliation(s)
- Anne E J Hillen
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands; Department of Pediatrics/Child Neurology, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - J Peter H Burbach
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands; Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, 1098 XH Amsterdam, The Netherlands; Department of Neuroimmunology, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA Amsterdam, The Netherlands.
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38
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Assis-Nascimento P, Tsenkina Y, Liebl DJ. EphB3 signaling induces cortical endothelial cell death and disrupts the blood-brain barrier after traumatic brain injury. Cell Death Dis 2018; 9:7. [PMID: 29311672 PMCID: PMC5849033 DOI: 10.1038/s41419-017-0016-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 09/20/2017] [Accepted: 10/03/2017] [Indexed: 12/14/2022]
Abstract
Damage to the cerebrovascular network is a major contributor to dysfunction in patients suffering from traumatic brain injury (TBI). Vessels are composed of lumen-forming endothelial cells that associate closely with both glial and neuronal units to establish a functional blood–brain barrier (BBB). Under normal physiological conditions, these vascular units play important roles in central nervous system (CNS) homeostasis by delivering oxygen and nutrients while filtering out molecules and cells that could be harmful; however, after TBI this system is disrupted. Here, we describe a novel role for a class of receptors, called dependence receptors, in regulating vessel stability and BBB integrity after CCI injury in mice. Specifically, we identified that EphB3 receptors function as a pro-apoptotic dependence receptor in endothelial cells (ECs) that contributes to increased BBB damage after CCI injury. In the absence of EphB3, we observed increased endothelial cell survival, reduced BBB permeability and enhanced interactions of astrocyte-EC membranes. Interestingly, the brain’s response to CCI injury is to reduce EphB3 levels and its ligand ephrinB3; however, the degree and timing of those reductions limit the protective response of the CNS. We conclude that EphB3 is a negative regulator of cell survival and BBB integrity that undermine tissue repair, and represents a protective therapeutic target for TBI patients.
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Affiliation(s)
- Poincyane Assis-Nascimento
- The Miami Project to Cure Paralysis, Department of Neurological surgery, University of Miami Miller School of Medicine, 1095 NW 14th Terrace, R-48, Miami, FL, 33136, USA
| | - Yanina Tsenkina
- The Miami Project to Cure Paralysis, Department of Neurological surgery, University of Miami Miller School of Medicine, 1095 NW 14th Terrace, R-48, Miami, FL, 33136, USA
| | - Daniel J Liebl
- The Miami Project to Cure Paralysis, Department of Neurological surgery, University of Miami Miller School of Medicine, 1095 NW 14th Terrace, R-48, Miami, FL, 33136, USA.
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39
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Yang JS, Wei HX, Chen PP, Wu G. Roles of Eph/ephrin bidirectional signaling in central nervous system injury and recovery. Exp Ther Med 2018; 15:2219-2227. [PMID: 29456630 PMCID: PMC5795627 DOI: 10.3892/etm.2018.5702] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 10/26/2017] [Indexed: 12/12/2022] Open
Abstract
Multiple cellular components are involved in the complex pathological process following central nervous system (CNS) injury, including neurons, glial cells and endothelial cells. Previous studies and neurotherapeutic clinical trials have assessed the molecular mechanisms that underlie neuronal cell death following CNS injury. However, this approach has largely failed to reduce CNS damage or improve the functional recovery of patients. Erythropoietin-producing human hepatocellular (Eph) receptors and ephrin ligands have attracted considerable attention since their discovery, due to their extensive distribution and unique bidirectional signaling between astrocytes and neurons. Previous studies have investigated the roles of Eph/ephrin bidirectional signaling in the developing central nervous system. It was determined that Eph/ephrin bidirectional signaling is expressed in various CNS regions and cell types, and that it serves diverse roles in the adult CNS. In the present review, the roles of Eph/ephrin bidirectional signaling in CNS injuries are assessed.
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Affiliation(s)
- Jin-Shan Yang
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Hui-Xing Wei
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Ping-Ping Chen
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
| | - Gang Wu
- Department of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350000, P.R. China
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40
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Tyzack GE, Hall CE, Sibley CR, Cymes T, Forostyak S, Carlino G, Meyer IF, Schiavo G, Zhang SC, Gibbons GM, Newcombe J, Patani R, Lakatos A. A neuroprotective astrocyte state is induced by neuronal signal EphB1 but fails in ALS models. Nat Commun 2017; 8:1164. [PMID: 29079839 PMCID: PMC5660125 DOI: 10.1038/s41467-017-01283-z] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 09/06/2017] [Indexed: 12/25/2022] Open
Abstract
Astrocyte responses to neuronal injury may be beneficial or detrimental to neuronal recovery, but the mechanisms that determine these different responses are poorly understood. Here we show that ephrin type-B receptor 1 (EphB1) is upregulated in injured motor neurons, which in turn can activate astrocytes through ephrin-B1-mediated stimulation of signal transducer and activator of transcription-3 (STAT3). Transcriptional analysis shows that EphB1 induces a protective and anti-inflammatory signature in astrocytes, partially linked to the STAT3 network. This is distinct from the response evoked by interleukin (IL)-6 that is known to induce both pro inflammatory and anti-inflammatory processes. Finally, we demonstrate that the EphB1-ephrin-B1 pathway is disrupted in human stem cell derived astrocyte and mouse models of amyotrophic lateral sclerosis (ALS). Our work identifies an early neuronal help-me signal that activates a neuroprotective astrocytic response, which fails in ALS, and therefore represents an attractive therapeutic target.
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Affiliation(s)
- Giulia E Tyzack
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, E.D. Adrian Building, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
- Department of Molecular Neuroscience, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Claire E Hall
- Department of Molecular Neuroscience, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Christopher R Sibley
- Division of Brain Sciences, Imperial College London, Burlington Danes Building Du Cane Road, London, W12 0NN, UK
| | - Tomasz Cymes
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, E.D. Adrian Building, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
| | - Serhiy Forostyak
- Institute of Experimental Medicine ASCR and Charles University in Prague, Department of Neuroscience, Videnská 1083, Prague 4, 142 20, Czech Republic
| | - Giulia Carlino
- Department of Molecular Neuroscience, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Ione F Meyer
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Giampietro Schiavo
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
- UK Dementia Research Institute at UCL, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Su-Chun Zhang
- Waisman Center, University of Wisconsin, 1500 Highland Avenue, Madison, WI, 53705, USA
| | - George M Gibbons
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, E.D. Adrian Building, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
| | - Jia Newcombe
- Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, WC1N 1PJ, UK
| | - Rickie Patani
- Department of Molecular Neuroscience, UCL Institute of Neurology, University College London, London, WC1N 3BG, UK.
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| | - András Lakatos
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, E.D. Adrian Building, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK.
- Addenbrooke's Hospital, Cambridge University Hospitals, Hills Road, Cambridge, CB2 0QQ, UK.
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Neuronal-Glial Interactions Maintain Chronic Neuropathic Pain after Spinal Cord Injury. Neural Plast 2017; 2017:2480689. [PMID: 28951789 PMCID: PMC5603132 DOI: 10.1155/2017/2480689] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/26/2017] [Accepted: 07/05/2017] [Indexed: 02/01/2023] Open
Abstract
The hyperactive state of sensory neurons in the spinal cord enhances pain transmission. Spinal glial cells have also been implicated in enhanced excitability of spinal dorsal horn neurons, resulting in pain amplification and distortions. Traumatic injuries of the neural system such as spinal cord injury (SCI) induce neuronal hyperactivity and glial activation, causing maladaptive synaptic plasticity in the spinal cord. Recent studies demonstrate that SCI causes persistent glial activation with concomitant neuronal hyperactivity, thus providing the substrate for central neuropathic pain. Hyperactive sensory neurons and activated glial cells increase intracellular and extracellular glutamate, neuropeptides, adenosine triphosphates, proinflammatory cytokines, and reactive oxygen species concentrations, all of which enhance pain transmission. In addition, hyperactive sensory neurons and glial cells overexpress receptors and ion channels that maintain this enhanced pain transmission. Therefore, post-SCI neuronal-glial interactions create maladaptive synaptic circuits and activate intracellular signaling events that permanently contribute to enhanced neuropathic pain. In this review, we describe how hyperactivity of sensory neurons contributes to the maintenance of chronic neuropathic pain via neuronal-glial interactions following SCI.
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42
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Zheng JY, Sun J, Ji CM, Shen L, Chen ZJ, Xie P, Sun YZ, Yu RT. Selective deletion of apolipoprotein E in astrocytes ameliorates the spatial learning and memory deficits in Alzheimer's disease (APP/PS1) mice by inhibiting TGF-β/Smad2/STAT3 signaling. Neurobiol Aging 2017; 54:112-132. [PMID: 28366226 DOI: 10.1016/j.neurobiolaging.2017.03.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 01/28/2017] [Accepted: 03/02/2017] [Indexed: 01/05/2023]
Abstract
Astrocytes and apolipoprotein E (apoE) play critical roles in cognitive function, not only under physiological conditions but also in some pathological situations, particularly in the pathological progression of Alzheimer's disease (AD). The regulatory mechanisms underlying the effect of apoE, derived from astrocytes, on cognitive deficits during AD pathology development are unclear. In this study, we generated amyloid precursor protein/apoE knockout (APP/apoEKO) and APP/glial fibrillary acidic protein (GFAP)-apoEKO mice (the AD mice model used in this study was based on the APP-familial Alzheimer disease overexpression) to investigate the role of apoE, derived from astrocytes, in AD pathology and cognitive function. To explore the mechanism, we investigated the amyloidogenic process related transforming growth factor β/mothers against decapentaplegic homolog 2/signal transducer and activator of transcription 3 (TGF-β/Smad2/STAT3) signaling pathway and further confirmed by administering TGF-β-overexpression adeno-associated virus (specific to astrocytes) to APP/GFAP-apoEKO mice and TGF-β-inhibition adeno-associated virus (specific to astrocytes) to APP/WT mice. Whole body deletion of apoE significantly ameliorated the spatial learning and memory impairment, reduced amyloid β-protein production and inhibited astrogliosis in APP/apoEKO mice, as well as specific deletion apoE in astrocytes in APP/GFAP-apoEKO mice. Moreover, amyloid β-protein accumulation was increased due to promotion of amyloidogenesis of APP, and astrogliosis was upregulated by activation of TGF-β/Smad2/STAT3 signaling. Furthermore, the overexpression of TGF-β in astrocytes in APP/GFAP-apoEKO mice abrogated the effects of apoE knockout. In contrast, repression of TGF-β in astrocytes of APP/WT mice exerted a therapeutic effect similar to apoE knockout. These data suggested that apoE derived from astrocytes contributes to the risk of AD through TGF-β/Smad2/STAT3 signaling activation. These findings enhance our understanding of the role of apoE, derived from astrocytes, in AD and suggest it to be a potential biomarker and therapeutic target for AD.
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Affiliation(s)
- Jin-Yu Zheng
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China; Department of Neurosurgery, Xuzhou Medical University, Xuzhou, Jiangsu, P. R. China
| | - Jian Sun
- Department of Anesthesiology, Huai'an Maternal and Child Health Hospital, Huai'an, Jiangsu, P. R. China
| | - Chun-Mei Ji
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China
| | - Lin Shen
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China
| | - Zhong-Jun Chen
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China
| | - Peng Xie
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China
| | - Yuan-Zhao Sun
- Department of Neurosurgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, P. R. China
| | - Ru-Tong Yu
- Department of Neurosurgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, P. R. China; Laboratory of Neurosurgery, Xuzhou Medical University, Xuzhou, Jiangsu, P. R. China.
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