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Jacobson PB, Mothe A, Levy A, Krakovsky M, Hooker BA, Zhang X, Mollon J, Mordashova Y, Droescher M, Weiss S, Barghorn S, Dreher I, Awwad K, Nimmrich V, Huang L, Fung E, Buck WR, Pfleeger K, Ziemann A, Smith E, Fox GB, Tator CH, Gold M. Neutralizing RGMa with Elezanumab Promotes Cerebroprotection and Recovery in Rabbit Middle Cerebral Artery Occlusion. Transl Stroke Res 2024; 15:805-817. [PMID: 37326791 PMCID: PMC11226526 DOI: 10.1007/s12975-023-01164-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/17/2023]
Abstract
Repulsive guidance molecule A (RGMa) is an inhibitor of neuronal growth and survival which is upregulated in the damaged central nervous system following acute spinal cord injury (SCI), traumatic brain injury, acute ischemic stroke (AIS), and other neuropathological conditions. Neutralization of RGMa is neuroprotective and promotes neuroplasticity in several preclinical models of neurodegeneration and injury including multiple sclerosis, AIS, and SCI. Given the limitations of current treatments for AIS due to narrow time windows to intervention (TTI), and restrictive patient selection criteria, there is significant unmet need for therapeutic agents that enable tissue survival and repair following acute ischemic damage for a broader population of stroke patients. In this preclinical study, we evaluated whether elezanumab, a human anti-RGMa monoclonal antibody, could improve neuromotor function and modulate neuroinflammatory cell activation following AIS with delayed intervention times up to 24 h using a rabbit embolic permanent middle cerebral artery occlusion model (pMCAO). In two replicate 28-day pMCAO studies, weekly intravenous infusions of elezanumab, over a range of doses and TTIs of 6 and 24 h after stroke, significantly improved neuromotor function in both pMCAO studies when first administered 6 h after stroke. All elezanumab treatment groups, including the 24 h TTI group, had significantly less neuroinflammation as assessed by microglial and astrocyte activation. The novel mechanism of action and potential for expanding TTI in human AIS make elezanumab distinct from current acute reperfusion therapies, and support evaluation in clinical trials of acute CNS damage to determine optimal dose and TTI in humans.
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Affiliation(s)
- Peer B Jacobson
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd, North Chicago, IL, 60064, USA.
| | - Andrea Mothe
- Division of Experimental and Translational Neuroscience, Krembil Brain Institute & University Health Network, Toronto, ON, M5T 0S8, Canada
| | | | | | - Bradley A Hooker
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Xiaomeng Zhang
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Jennifer Mollon
- Data and Statistical Sciences, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, 67061, KnollstrasseLudwigshafen, Germany
| | - Yulia Mordashova
- Data and Statistical Sciences, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, 67061, KnollstrasseLudwigshafen, Germany
| | - Mathias Droescher
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Sabine Weiss
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Stefan Barghorn
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Ingeborg Dreher
- Department of Drug Metabolism, Pharmacokinetics and Bioanalysis, AbbVie Deutschland GmbH & Co. KG, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Khader Awwad
- Department of Drug Metabolism, Pharmacokinetics and Bioanalysis, AbbVie Deutschland GmbH & Co. KG, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Volker Nimmrich
- Department of Drug Metabolism, Pharmacokinetics and Bioanalysis, AbbVie Deutschland GmbH & Co. KG, 67061, Knollstrasse, Ludwigshafen, Germany
| | - Lili Huang
- AbbVie Biologics, AbbVie Bioresearch Center, 100 Research Drive, Worcester, MA, 01605, USA
| | - Emma Fung
- AbbVie Biologics, AbbVie Bioresearch Center, 100 Research Drive, Worcester, MA, 01605, USA
| | - Wayne R Buck
- Preclinical Safety, AbbVie Inc, 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Kimberly Pfleeger
- Department of Neuroscience Development, AbbVie Inc, 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Adam Ziemann
- Department of Neuroscience Development, AbbVie Inc, 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Elaine Smith
- Department of Neuroscience Development, AbbVie Inc, 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Gerard B Fox
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd, North Chicago, IL, 60064, USA
| | - Charles H Tator
- Division of Experimental and Translational Neuroscience, Krembil Brain Institute & University Health Network, Toronto, ON, M5T 0S8, Canada
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Michael Gold
- Department of Neuroscience Development, AbbVie Inc, 1 North Waukegan Rd, North Chicago, IL, 60064, USA
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Mosneag IE, Flaherty SM, Wykes RC, Allan SM. Stroke and Translational Research - Review of Experimental Models with a Focus on Awake Ischaemic Induction and Anaesthesia. Neuroscience 2024; 550:89-101. [PMID: 38065289 DOI: 10.1016/j.neuroscience.2023.11.034] [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: 09/13/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023]
Abstract
Animal models are an indispensable tool in the study of ischaemic stroke with hundreds of drugs emerging from the preclinical pipeline. However, all of these drugs have failed to translate into successful treatments in the clinic. This has brought into focus the need to enhance preclinical studies to improve translation. The confounding effects of anaesthesia on preclinical stroke modelling has been raised as an important consideration. Various volatile and injectable anaesthetics are used in preclinical models during stroke induction and for outcome measurements such as imaging or electrophysiology. However, anaesthetics modulate several pathways essential in the pathophysiology of stroke in a dose and drug dependent manner. Most notably, anaesthesia has significant modulatory effects on cerebral blood flow, metabolism, spreading depolarizations, and neurovascular coupling. To minimise anaesthetic complications and improve translational relevance, awake stroke induction has been attempted in limited models. This review outlines anaesthetic strategies employed in preclinical ischaemic rodent models and their reported cerebral effects. Stroke related complications are also addressed with a focus on infarct volume, neurological deficits, and thrombolysis efficacy. We also summarise routinely used focal ischaemic stroke rodent models and discuss the attempts to induce some of these models in awake rodents.
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Affiliation(s)
- Ioana-Emilia Mosneag
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom.
| | - Samuel M Flaherty
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom
| | - Robert C Wykes
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom; Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Stuart M Allan
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom
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3
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Lee HJ, Jung DH, Kim NK, Shin HK, Choi BT. Effects of electroacupuncture on the functionality of NG2-expressing cells in perilesional brain tissue of mice following ischemic stroke. Neural Regen Res 2021; 17:1556-1565. [PMID: 34916441 PMCID: PMC8771106 DOI: 10.4103/1673-5374.330611] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Neural/glial antigen 2 (NG2)-expressing cells has multipotent stem cell activity under cerebral ischemia. Our study examined the effects of electroacupuncture (EA) therapy (2 Hz, 1 or 3 mA, 20 minutes) at the Sishencong acupoint on motor function after ischemic insult in the brain by investigating the rehabilitative potential of NG2-derived cells in a mouse model of ischemic stroke. EA stimulation alleviated motor deficits caused by ischemic stroke, and 1 mA EA stimulation was more efficacious than 3 mA EA stimulation or positive control treatment with edaravone, a free radical scavenger. The properties of NG2-expressing cells were altered with 1 mA EA stimulation, enhancing their survival in perilesional brain tissue via reduction of tumor necrosis factor alpha expression. EA stimulation robustly activated signaling pathways related to proliferation and survival of NG2-expressing cells and increased the expression of neurotrophic factors such as brain-derived neurotrophic factor, tumor growth factor beta, and neurotrophin 3. In the perilesional striatum, EA stimulation greatly increased the number of NG2-expressing cells double-positive for oligodendrocyte, endothelial cell, and microglia/macrophage markers (CC1, CD31, and CD68). EA therapy also greatly activated brain-derived neurotrophic factor/tropomyosin receptor kinase B and glycogen synthase kinase 3 beta signaling. Our results indicate that EA therapy may prevent functional loss at the perilesional site by enhancing survival and differentiation of NG2-expressing cells via the activation of brain-derived neurotrophic factor -induced signaling, subsequently ameliorating motor dysfunction. The animal experiments were approved by the Animal Ethics Committee of Pusan National University (approval Nos. PNU2019-2199 and PNU2019-2884) on April 8, 2019 and June 19, 2019.
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Affiliation(s)
- Hong Ju Lee
- Department of Korean Medical Science, School of Korean Medicine; Graduate Training Program of Korean Medicine for Healthy Aging, Pusan National University, Yangsan, Republic of Korea
| | - Da Hee Jung
- Department of Korean Medical Science, School of Korean Medicine; Graduate Training Program of Korean Medicine for Healthy Aging, Pusan National University, Yangsan, Republic of Korea
| | - Nam Kwen Kim
- Department of Korean Ophthalmology, Otolaryngology and Dermatology, School of Korean Medicine, Pusan National University, Yangsan, Republic of Korea
| | - Hwa Kyoung Shin
- Department of Korean Medical Science, School of Korean Medicine; Graduate Training Program of Korean Medicine for Healthy Aging, Pusan National University, Yangsan, Republic of Korea
| | - Byung Tae Choi
- Department of Korean Medical Science, School of Korean Medicine; Graduate Training Program of Korean Medicine for Healthy Aging, Pusan National University, Yangsan, Republic of Korea
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Takeda H, Yamaguchi T, Yano H, Tanaka J. Microglial metabolic disturbances and neuroinflammation in cerebral infarction. J Pharmacol Sci 2020; 145:130-139. [PMID: 33357771 DOI: 10.1016/j.jphs.2020.11.007] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/09/2020] [Accepted: 11/19/2020] [Indexed: 12/12/2022] Open
Abstract
Cerebral ischemia/reperfusion injury activates microglia, resident immune cells in the brain, and allows the infiltration of circulating immune cells into the ischemic lesions. Microglia play both exacerbating and protective roles in pathological processes and are thus often referred to as "double-edged swords." In ischemic brains, blood-borne macrophages play a role that is distinct from that of resident activated microglia. Recently, the metabolic alteration of immune cells in the pathogenesis of inflammatory disorders including cerebral infarction has become a critical target for investigation. We begin this review by describing the multifaceted functions of microglia in cerebral infarction. Next, we focus on the metabolic alterations that occur in microglia during pathological processes. We also discuss morphological changes that take place in the mitochondria, leading to functional disturbances, accompanied by alterations in microglial function. Moreover, we describe the involvement of the reactive oxygen species that are produced during aberrant metabolic activity. Finally, we discuss therapeutic strategies to ameliorate aggravative changes in metabolism.
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Affiliation(s)
- Haruna Takeda
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Teruaki Yamaguchi
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Hajime Yano
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan.
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5
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Zhu X, Fréchou M, Schumacher M, Guennoun R. Cerebroprotection by progesterone following ischemic stroke: Multiple effects and role of the neural progesterone receptors. J Steroid Biochem Mol Biol 2019; 185:90-102. [PMID: 30031789 DOI: 10.1016/j.jsbmb.2018.07.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 12/21/2022]
Abstract
Treatment with progesterone limits brain damage after stroke. However, the cellular bases of the cerebroprotective effects of progesterone are not well documented. The aims of this study were to determine neural cells and functions that are affected by progesterone treatment and the role of neural progesterone receptors (PR) after stroke. Adult male PRNesCre mice, selectively lacking PR in the central nervous system, and their control PRloxP/loxP littermates were subjected to transient ischemia by middle cerebral artery occlusion (MCAO) for 30 min. Mice received either progesterone (8 mg/kg) or vehicle at 1-, 6- and 24- hrs post-MCAO and outcomes were analyzed at 48 h post-MCAO. In PRloxP/loxP mice, progesterone exerted multiple effects on different neural cell types, improved motor functional outcomes and reduced total infarct volumes. In the peri-infarct, progesterone increased the density of neurons (NeuN+ cells), of cells of the oligodendroglial lineage (Olig2+ cells) and of oligodendrocyte progenitors (OP, NG2+ cells). Progesterone decreased the density of activated astrocytes (GFAP+ cells) and reactive microglia (Iba1+ cells) coexpressing the mannose receptor type 1 CD206 marker. Progesterone also reduced the expression of aquaporin 4 (AQP4), the water channel involved in both edema formation and resorption. The beneficial effects of progesterone were not observed in PRNesCre mice. Our findings show that progesterone treatment exerts beneficial effects on neurons, oligodendroglial cells and neuroinflammatory responses via PR. These findings demonstrate that progesterone is a pleiotropic cerebroprotective agent and that neural PR represent a therapeutic target for stroke cerebroprotection.
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Affiliation(s)
- Xiaoyan Zhu
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Magalie Fréchou
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Michael Schumacher
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Rachida Guennoun
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
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Morphological characterization of NG2 glia and their association with neuroglial cells in the 3-nitropropionic acid-lesioned striatum of rat. Sci Rep 2018; 8:5942. [PMID: 29654253 PMCID: PMC5899159 DOI: 10.1038/s41598-018-24385-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 04/03/2018] [Indexed: 01/18/2023] Open
Abstract
Our aim was to examine the spatiotemporal profiles and phenotypic characteristics of neuron-glia antigen 2 (NG2) glia and their associations with neuroglial cells in striatal lesions due to the mitochondrial toxin 3-nitropropionic acid (3-NP). In control striatum, weak NG2 immunoreactivity was restricted to resting NG2 glia with thin processes, but prominent NG2 expression was noted on activated microglia/macrophages, and reactive NG2 glia in the lesion core after 3-NP injection. Activation of NG2 glia, including enhanced proliferation and morphological changes, had a close spatiotemporal relationship with infiltration of activated microglia into the lesion core. Thick and highly branched processes of reactive NG2 glia formed a cellular network in the astrocyte-free lesion core and primarily surrounded developing cavities 2–4 weeks post-lesion. NG2 glia became associated with astrocytes in the lesion core and the border of cavities over the chronic interval of 4–8 weeks. Immunoelectron microscopy indicated that reactive NG2 glia had large euchromatic nuclei with prominent nucleoli and thick and branched processes that ramified distally. Thus, our data provide detailed information regarding the morphologies of NG2 glia in the lesion core, and support the link between transformation of NG2 glia to the reactive form and microglial activation/recruitment in response to brain insults.
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Michalski D, Keck AL, Grosche J, Martens H, Härtig W. Immunosignals of Oligodendrocyte Markers and Myelin-Associated Proteins Are Critically Affected after Experimental Stroke in Wild-Type and Alzheimer Modeling Mice of Different Ages. Front Cell Neurosci 2018; 12:23. [PMID: 29467621 PMCID: PMC5807905 DOI: 10.3389/fncel.2018.00023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/15/2018] [Indexed: 12/31/2022] Open
Abstract
Because stroke therapies are still limited and patients are often concerned by long-term sequelae with significant impairment of daily living, elaborated neuroprotective strategies are needed. During the last decades, research substantially improved the knowledge on cellular pathologies responsible for stroke-related tissue damage. In this context, the neurovascular unit (NVU) concept has been established, summarizing the affections of neurons, associated astrocytes and the vasculature. Although oligodendrocytes were already identified to play a major role in other brain pathologies, their role during stroke evolution and long-lasting tissue damage is poorly understood. This study aims to explore oligodendrocyte structures, i.e., oligodendrocytes and their myelin-associated proteins, after experimental focal cerebral ischemia. For translational issues, different ages and genotypes including an Alzheimer-like background were considered to mimic potential co-morbidities. Three- and 12-month-old wild-type and triple-transgenic mice were subjected to unilateral middle cerebral artery occlusion. Immunofluorescence labeling was performed on forebrain tissues affected by 24 h of ischemia to visualize the oligodendrocyte-specific protein (OSP), the myelin basic protein (MBP), and the neuron-glia antigen 2 (NG2) with reference to the ischemic lesion. Subsequent analyses concomitantly detected the vasculature and the 2′, 3′-cyclic nucleotide-3′-phosphodiesterase (CNPase) to consider the NVU concept and to explore the functional relevance of histochemical data on applied oligodendrocyte markers. While the immunosignal of NG2 was found to be nearly absent 24 h after ischemia onset, enhanced immunoreactivities for OSP and especially MBP were observed in close regional association to the vasculature. Added quantitative analyses based on inter-hemispheric differences of MBP-immunoreactivity revealed a shell-like pattern with a significant increase directly in the ischemic core, followed by a gradual decline toward the striatum, the ischemic border zone and the lateral neocortex. This observation was consistent in subsequent analyses on the potential impact of age and genetic background. Furthermore, immunoreactivities for CNPase, MBP, and OSP were found to be simultaneously enhanced. In conclusion, this study provides evidence for a critical role of oligodendrocyte structures in the early phase after experimental stroke, strengthening their involvement in the ischemia-affected NVU. Consequently, oligodendrocytes and their myelin-associated proteins may qualify as potential targets for neuroprotective and regenerative approaches in stroke.
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Affiliation(s)
| | - Anna L Keck
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | | | | | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
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Islam A, Choudhury ME, Kigami Y, Utsunomiya R, Matsumoto S, Watanabe H, Kumon Y, Kunieda T, Yano H, Tanaka J. Sustained anti-inflammatory effects of TGF-β1 on microglia/macrophages. Biochim Biophys Acta Mol Basis Dis 2017; 1864:721-734. [PMID: 29269050 DOI: 10.1016/j.bbadis.2017.12.022] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 12/07/2017] [Accepted: 12/13/2017] [Indexed: 12/26/2022]
Abstract
Ischemic brain injuries caused release of damage-associated molecular patterns (DAMPs) that activate microglia/macrophages (MG/MPs) by binding to Toll-like receptors. Using middle cerebral artery transiently occluded rats, we confirmed that MG/MPs expressed inducible nitric oxide synthase (iNOS) on 3days after reperfusion (dpr) in ischemic rat brain. iNOS expression almost disappeared on 7dpr when transforming growth factor-β1 (TGF-β1) expression was robustly increased. After transient incubation with TGF-β1 for 24h, rat primary microglial cells were incubated with lipopolysaccharide (LPS) and released NO level was measured. The NO release was persistently suppressed even 72h after removal of TGF-β1. The sustained TGF-β1 effects were not attributable to microglia-derived endogenous TGF-β1, as revealed by TGF-β1 knockdown and in vitro quantification studies. Then, boiled supernatants prepared from ischemic brain tissues showed the similar sustained inhibitory effects on LPS-treated microglial cells that were prevented by the TGF-β1 receptor-selective blocker SB525334. After incubation with TGF-β1 for 24h and its subsequent removal, LPS-induced phosphorylation of IκB kinases (IKKs), IκB degradation, and NFκB nuclear translocation were inhibited in a sustained manner. SB525334 abolished all these effects of TGF-β1. In consistent with the in vitro results, phosphorylated IKK-immunoreactivity was abundant in MG/MPs in ischemic brain lesion on 3dpr, whereas it was almost disappeared on 7dpr. The findings suggest that abundantly produced TGF-β1 in ischemic brain displays sustained anti-inflammatory effects on microglial cells by persistently inhibiting endogenous Toll-like receptor ligand-induced IκB degradation.
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Affiliation(s)
- Afsana Islam
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | | | - Yuka Kigami
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Ryo Utsunomiya
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Shirabe Matsumoto
- Department of Neurosurgery, Graduate School of Medicine, Ehime University, Japan
| | - Hideaki Watanabe
- Department of Neurosurgery, Graduate School of Medicine, Ehime University, Japan
| | - Yoshiaki Kumon
- Department of Regeneration of Community Medicine, Graduate School of Medicine, Ehime University, Japan
| | - Takeharu Kunieda
- Department of Neurosurgery, Graduate School of Medicine, Ehime University, Japan
| | - Hajime Yano
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan.
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Osteopontin Augments M2 Microglia Response and Separates M1- and M2-Polarized Microglial Activation in Permanent Focal Cerebral Ischemia. Mediators Inflamm 2017; 2017:7189421. [PMID: 29104378 PMCID: PMC5632451 DOI: 10.1155/2017/7189421] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 07/30/2017] [Accepted: 08/29/2017] [Indexed: 01/17/2023] Open
Abstract
Background Focal cerebral ischemia induces distinct neuroinflammatory processes. We recently reported the extracellular phosphor-glyco-protein osteopontin (OPN) to directly affect primary microglia in vitro, promoting survival while shifting their inflammatory profile towards a more neutral phenotype. We here assessed the effects of OPN on microglia after stroke in vivo, with focus on infarct demarcation. Methods Animals underwent focal photothrombotic stroke and were injected intracerebroventricularly with 500 μg OPN or vehicle. Immunohistochemistry assessed neuronal damage and infarct volume, neovascularisation, glial scar formation, microglial activation, and M1 and M2 polarisation. Results After photothrombotic stroke, areas covered by M1 and M2 microglia substantially overlapped. OPN treatment reduced that overlap, with microglia appearing more spread out and additionally covering the infarct core. OPN additionally modulated the quantity of microglia subpopulations, reducing iNOS+ M1 cells while increasing M2 microglia, shifting the M1/M2 balance towards an M2 phenotype. Moreover, OPN polarized astrocytes towards the infarct. Conclusion Microglial activation and M1 and M2 polarization have distinct but overlapping spatial patterns in permanent focal ischemia. Data suggest that OPN is involved in separating M1 and M2 subpopulations, as well as in shifting microglia polarization towards the M2 phenotype modulating beneficially inflammatory responses after focal infarction.
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Jiang MQ, Zhao YY, Cao W, Wei ZZ, Gu X, Wei L, Yu SP. Long-term survival and regeneration of neuronal and vasculature cells inside the core region after ischemic stroke in adult mice. Brain Pathol 2016; 27:480-498. [PMID: 27514013 DOI: 10.1111/bpa.12425] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 07/27/2016] [Indexed: 12/20/2022] Open
Abstract
Focal cerebral ischemia results in an ischemic core surrounded by the peri-infarct region (penumbra). Most research attention has been focused on penumbra while the pattern of cell fates inside the ischemic core is poorly defined. In the present investigation, we tested the hypothesis that, inside the ischemic core, some neuronal and vascular cells could survive the initial ischemic insult while regenerative niches might exist many days after stroke in the adult brain. Adult mice were subjected to focal cerebral ischemia induced by permanent occlusion of distal branches of the middle cerebral artery (MCA) plus transient ligations of bilateral common carotid artery (CCA). The ischemic insult uniformly reduced the local cerebral blood flow (LCBF) by 90%. Massive cell death occurred due to multiple mechanisms and a significant infarction was cultivated in the ischemic cortex 24 h later. Nevertheless, normal or even higher levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) persistently remained in the core tissue, some NeuN-positive and Glut-1/College IV-positive cells with intact ultrastructural features resided in the core 7-14 days post stroke. BrdU-positive but TUNEL-negative neuronal and endothelial cells were detected in the core where extensive extracellular matrix infrastructure developed. Meanwhile, GFAP-positive astrocytes accumulated in the penumbra and Iba-1-positive microglial/macrophages invaded the core several days after stroke. The long term survival of neuronal and vascular cells inside the ischemic core was also seen after a severe ischemic stroke induced by permanent embolic occlusion of the MCA. We demonstrate that a therapeutic intervention of pharmacological hypothermia could save neurons/endothelial cells inside the core. These data suggest that the ischemic core is an actively regulated brain region with residual and newly formed viable neuronal and vascular cells acutely and chronically after at least some types of ischemic strokes.
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Affiliation(s)
- Michael Qize Jiang
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA
| | - Ying-Ying Zhao
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA.,Department of Neurology, Friendship Hospital, Capital Medical University, Beijing, China
| | - Wenyuan Cao
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA
| | - Zheng Zachory Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affair Medical Center, Decatur, GA
| | - Xiaohuan Gu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affair Medical Center, Decatur, GA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA.,Department of Neurology, Friendship Hospital, Capital Medical University, Beijing, China
| | - Shan Ping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affair Medical Center, Decatur, GA
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Wang YF, Parpura V. Central Role of Maladapted Astrocytic Plasticity in Ischemic Brain Edema Formation. Front Cell Neurosci 2016; 10:129. [PMID: 27242440 PMCID: PMC4865516 DOI: 10.3389/fncel.2016.00129] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/29/2016] [Indexed: 12/24/2022] Open
Abstract
Brain edema formation and the ensuing brain damages are the major cause of high mortality and long term disability following the occurrence of ischemic stroke. In this process, oxygen and glucose deprivation and the resulting reperfusion injury play primary roles. In response to the ischemic insult, the neurovascular unit experiences both intracellular and extracellular edemas, associated with maladapted astrocytic plasticity. The astrocytic plasticity includes both morphological and functional plasticity. The former involves a reactive gliosis and the subsequent glial retraction. It relates to the capacity of astrocytes to buffer changes in extracellular chemical levels, particularly K+ and glutamate, as well as the integrity of the blood-brain barrier (BBB). The latter involves the expression and activity of a series of ion and water transport proteins. These molecules are grouped together around glial fibrillary acidic protein (GFAP) and water channel protein aquaporin 4 (AQP4) to form functional networks, regulate hydromineral balance across cell membranes and maintain the integrity of the BBB. Intense ischemic challenges can disrupt these capacities of astrocytes and result in their maladaptation. The maladapted astrocytic plasticity in ischemic stroke cannot only disrupt the hydromineral homeostasis across astrocyte membrane and the BBB, but also leads to disorders of the whole neurovascular unit. This review focuses on how the maladapted astrocytic plasticity in ischemic stroke plays the central role in the brain edema formation.
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Affiliation(s)
- Yu-Feng Wang
- Department of Physiology, School of Basic Medical Sciences, Harbin Medical University Harbin, China
| | - Vladimir Parpura
- Department of Neurobiology, University of Alabama at Birmingham Birmingham, AL, USA
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Nishioka R, Sugimoto K, Aono H, Mise A, Choudhury ME, Miyanishi K, Islam A, Fujita T, Takeda H, Takahashi H, Yano H, Tanaka J. Treadmill exercise ameliorates ischemia-induced brain edema while suppressing Na⁺/H⁺ exchanger 1 expression. Exp Neurol 2015; 277:150-161. [PMID: 26724742 DOI: 10.1016/j.expneurol.2015.12.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/15/2015] [Accepted: 12/22/2015] [Indexed: 01/23/2023]
Abstract
Exercise may be one of the most effective and sound therapies for stroke; however, the mechanisms underlying the curative effects remain unclear. In this study, the effects of forced treadmill exercise with electric shock on ischemic brain edema were investigated. Wistar rats were subjected to transient (90 min) middle cerebral artery occlusion (tMCAO). Eighty nine rats with substantially large ischemic lesions were evaluated using magnetic resonance imaging (MRI) and were randomly assigned to exercise and non-exercise groups. The rats were forced to run at 4-6m/s for 10 min/day on days 2, 3 and 4. Brain edema was measured on day 5 by MRI, histochemical staining of brain sections and tissue water content determination (n=7, each experiment). Motor function in some rats was examined on day 30 (n=6). Exercise reduced brain edema (P<0.05-0.001, varied by the methods) and ameliorated motor function (P<0.05). The anti-glucocorticoid mifepristone or the anti-mineralocorticoid spironolactone abolished these effects, but orally administered corticosterone mimicked the ameliorating effects of exercise. Exercise prevented the ischemia-induced expression of mRNA encoding aquaporin 4 (AQP4) and Na(+)/H(+) exchangers (NHEs) (n=5 or 7, P<0.01). Microglia and NG2 glia expressed NHE1 in the peri-ischemic region of rat brains and also in mixed glial cultures. Corticosterone at ~10nM reduced NHE1 and AQP4 expression in mixed glial and pure microglial cultures. Dexamethasone and aldosterone at 10nM did not significantly alter NHE1 and AQP4 expression. Exposure to a NHE inhibitor caused shrinkage of microglial cells. These results suggest that the stressful short-period and slow-paced treadmill exercise suppressed NHE1 and AQP4 expression resulting in the amelioration of brain edema at least partly via the moderate increase in plasma corticosterone levels.
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Affiliation(s)
- Ryutaro Nishioka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Kana Sugimoto
- Department of Legal Medicine, Graduate School of Medicine/Faculty of Medicine, Osaka University, Japan
| | - Hitomi Aono
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Ayano Mise
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Mohammed E Choudhury
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Kazuya Miyanishi
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Afsana Islam
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Takahiro Fujita
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Haruna Takeda
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Hisaaki Takahashi
- Center for Advanced Research and Education, Asahikawa Medical University, Japan
| | - Hajime Yano
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan.
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Huang C, Sakry D, Menzel L, Dangel L, Sebastiani A, Krämer T, Karram K, Engelhard K, Trotter J, Schäfer MK. Lack of NG2 exacerbates neurological outcome and modulates glial responses after traumatic brain injury. Glia 2015; 64:507-23. [DOI: 10.1002/glia.22944] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 11/05/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Changsheng Huang
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Dominik Sakry
- Department of Biology, Molecular Cell Biology; Johannes Gutenberg-University Mainz; Germany
| | - Lutz Menzel
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Larissa Dangel
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Anne Sebastiani
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Tobias Krämer
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Khalad Karram
- Department of Biology, Molecular Cell Biology; Johannes Gutenberg-University Mainz; Germany
- Institute for Molecular Medicine, University Medical Center, Johannes Gutenberg-University Mainz; Germany
| | - Kristin Engelhard
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University Mainz; Germany
| | - Jacqueline Trotter
- Department of Biology, Molecular Cell Biology; Johannes Gutenberg-University Mainz; Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University Mainz; Germany
| | - Michael K.E. Schäfer
- Department of Anesthesiology; University Medical Center, Johannes Gutenberg-University Mainz; Germany
- Focus Program Translational Neurosciences (FTN) of the Johannes Gutenberg-University Mainz; Germany
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Walberer M, Rueger MA. The macrosphere model-an embolic stroke model for studying the pathophysiology of focal cerebral ischemia in a translational approach. ANNALS OF TRANSLATIONAL MEDICINE 2015. [PMID: 26207251 DOI: 10.3978/j.issn.2305-5839.2015.04.02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The main challenge of stroke research is to translate promising experimental findings from the bench to the bedside. Many suggestions have been made how to achieve this goal, identifying the need for appropriate experimental animal models as one key issue. We here discuss the macrosphere model of focal cerebral ischemia in the rat, which closely resembles the pathophysiology of human stroke both in its acute and chronic phase. Key pathophysiological processes such as brain edema, cortical spreading depolarizations (CSD), neuroinflammation, and stem cell-mediated regeneration are observed in this stroke model, following characteristic temporo-spatial patterns. Non-invasive in vivo imaging allows studying the macrosphere model from the very onset of ischemia up to late remodeling processes in an intraindividual and longitudinal fashion. Such a design of pre-clinical stroke studies provides the basis for a successful translation into the clinic.
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Affiliation(s)
- Maureen Walberer
- 1 Department of Neurology, University Hospital of Cologne, Cologne, Germany ; 2 Max-Planck-Institute for Metabolism Research, Cologne, Germany ; 3 Animal Welfare Office, University of Cologne, Germany
| | - Maria Adele Rueger
- 1 Department of Neurology, University Hospital of Cologne, Cologne, Germany ; 2 Max-Planck-Institute for Metabolism Research, Cologne, Germany ; 3 Animal Welfare Office, University of Cologne, Germany
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Hjalmarsson C, Bjerke M, Andersson B, Blennow K, Zetterberg H, Aberg ND, Olsson B, Eckerström C, Bokemark L, Wallin A. Neuronal and glia-related biomarkers in cerebrospinal fluid of patients with acute ischemic stroke. J Cent Nerv Syst Dis 2014; 6:51-8. [PMID: 24932109 PMCID: PMC4039292 DOI: 10.4137/jcnsd.s13821] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 03/09/2014] [Accepted: 03/12/2014] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Cerebral ischemia promotes morphological reactions of the neurons, astrocytes, oligodendrocytes, and microglia in experimental studies. Our aim was to examine the profile of CSF (cerebrospinal fluid) biomarkers and their relation to stroke severity and degree of white matter lesions (WML). METHODS A total of 20 patients (mean age 76 years) were included within 5–10 days after acute ischemic stroke (AIS) onset. Stroke severity was assessed using NIHSS (National Institute of Health stroke scale). The age-related white matter changes (ARWMC) scale was used to evaluate the extent of WML on CT-scans. The concentrations of specific CSF biomarkers were analyzed. RESULTS Patients with AIS had significantly higher levels of NFL (neurofilament, light), T-tau, myelin basic protein (MBP), YKL-40, and glial fibrillary acidic protein (GFAP) compared with controls; T-Tau, MBP, GFAP, and YKL-40 correlated with clinical stroke severity, whereas NFL correlated with severity of WML (tested by Mann–Whitney test). CONCLUSIONS Several CSF biomarkers increase in AIS, and they correlate to clinical stroke severity. However, only NFL was found to be a marker of degree of WML.
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Affiliation(s)
- Clara Hjalmarsson
- The Stroke Unit, Department of Internal Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Maria Bjerke
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
| | - Björn Andersson
- The Stroke Unit, Department of Internal Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden. ; UCL Institute of Neurology, Queen Square, London, UK
| | - N David Aberg
- The Stroke Unit, Department of Internal Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Bob Olsson
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
| | - Carl Eckerström
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
| | - Lena Bokemark
- The Stroke Unit, Department of Internal Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Anders Wallin
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, The Sahlgrenska Academy, Gothenburg, Sweden
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Sugimoto K, Nishioka R, Ikeda A, Mise A, Takahashi H, Yano H, Kumon Y, Ohnishi T, Tanaka J. Activated microglia in a rat stroke model express NG2 proteoglycan in peri-infarct tissue through the involvement of TGF-β1. Glia 2013; 62:185-98. [PMID: 24311432 DOI: 10.1002/glia.22598] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/20/2013] [Accepted: 10/22/2013] [Indexed: 12/12/2022]
Abstract
We investigated activated microglia in ischemic brain lesions from rats that had been subjected to transient middle cerebral artery occlusion. Activated microglia expressing NG2 chondroitin sulfate proteoglycan (NG2) were found only in the narrow zone (demarcation zone) that demarcated the peri-infarct tissue and ischemic core. NG2(-) activated microglia were abundantly distributed in the peri-infarct tissue outside the demarcation zone. NG2(+) microglia but not NG2(-) microglia expressed both CD68 and a triggering receptor expressed on myeloid cells 2 (TREM-2), suggesting that NG2(+) microglia eliminated apoptotic neurons. In fact, NG2(+) microglia often attached to degenerating neurons and sometimes internalized NeuN(+) or neurofilament protein(+) material. Kinetic studies using quantitative real-time RT-PCR revealed that expression of transforming growth factor-β1 (TGF-β1) was most evident in the ischemic core; with this marker produced mainly by macrophages located in this region. TGF-β receptor mRNA expression peaked at 3 days post reperfusion (dpr) in the peri-infarct tissue, including the demarcation zone. Primary cultured rat microglia also expressed the receptor mRNA. In response to TGF-β1, primary microglia enhanced the expression of NG2 protein and TREM-2 mRNA as well as migratory activity. A TGF-β1 inhibitor, SB525334, abolished these effects. The present results suggest that TGF-β1 produced in the ischemic core diffused toward the peri-infarct tissue, driving activated microglial cells to eliminate degenerating neurons. Appropriate control of NG2(+) microglia in the demarcation zone might be a novel target for the suppression of secondary neurodegeneration in the peri-infarct tissue.
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Affiliation(s)
- Kana Sugimoto
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan
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Ionic transporter activity in astrocytes, microglia, and oligodendrocytes during brain ischemia. J Cereb Blood Flow Metab 2013; 33:969-82. [PMID: 23549380 PMCID: PMC3705429 DOI: 10.1038/jcbfm.2013.44] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 01/09/2023]
Abstract
Glial cells constitute a large percentage of cells in the nervous system. During recent years, a large number of studies have critically attributed to glia a new role which no longer reflects the long-held view that glia constitute solely a silent and passive supportive scaffolding for brain cells. Indeed, it has been hypothesized that glia, partnering neurons, have a much more actively participating role in brain function. Alteration of intraglial ionic homeostasis in response to ischemic injury has a crucial role in inducing and maintaining glial responses in the ischemic brain. Therefore, glial transporters as potential candidates in stroke intervention are becoming promising targets to enhance an effective and additional therapy for brain ischemia. In this review, we will describe in detail the role played by ionic transporters in influencing astrocyte, microglia, and oligodendrocyte activity and the implications that these transporters have in the progression of ischemic lesion.
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