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Tang Y, Wu X, Li J, Li Y, Xu X, Li G, Zhang P, Qin C, Wu LJ, Tang Z, Tian DS. The Emerging Role of Microglial Hv1 as a Target for Immunomodulation in Myelin Repair. Aging Dis 2024; 15:1176-1203. [PMID: 38029392 PMCID: PMC11081154 DOI: 10.14336/ad.2023.1107] [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: 08/17/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023] Open
Abstract
In the central nervous system (CNS), the myelin sheath ensures efficient interconnection between neurons and contributes to the regulation of the proper function of neuronal networks. The maintenance of myelin and the well-organized subtle process of myelin plasticity requires cooperation among myelin-forming cells, glial cells, and neural networks. The process of cooperation is fragile, and the balance is highly susceptible to disruption by microenvironment influences. Reactive microglia play a critical and complicated role in the demyelination and remyelination process. Recent studies have shown that the voltage-gated proton channel Hv1 is selectively expressed in microglia in CNS, which regulates intracellular pH and is involved in the production of reactive oxygen species, underlying multifaceted roles in maintaining microglia function. This paper begins by examining the molecular mechanisms of demyelination and emphasizes the crucial role of the microenvironment in demyelination. It focuses specifically on the role of Hv1 in myelin repair and its therapeutic potential in CNS demyelinating diseases.
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Affiliation(s)
- Yingxin Tang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Xuan Wu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Jiarui Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Yuanwei Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Xiaoxiao Xu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Gaigai Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Ping Zhang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Chuan Qin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Zhouping Tang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Dai-Shi Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Ames S, Adams K, Geisen ME, Stirling DP. Ca 2+-induced myelin pathology precedes axonal spheroid formation and is mediated in part by store-operated Ca 2+ entry after spinal cord injury. Neural Regen Res 2023; 18:2720-2726. [PMID: 37449636 DOI: 10.4103/1673-5374.373656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
The formation of axonal spheroid is a common feature following spinal cord injury. To further understand the source of Ca2+ that mediates axonal spheroid formation, we used our previously characterized ex vivo mouse spinal cord model that allows precise perturbation of extracellular Ca2+. We performed two-photon excitation imaging of spinal cords isolated from Thy1YFP+ transgenic mice and applied the lipophilic dye, Nile red, to record dynamic changes in dorsal column axons and their myelin sheaths respectively. We selectively released Ca2+ from internal stores using the Ca2+ ionophore ionomycin in the presence or absence of external Ca2+. We reported that ionomycin dose-dependently induces pathological changes in myelin and pronounced axonal spheroid formation in the presence of normal 2 mM Ca2+ artificial cerebrospinal fluid. In contrast, removal of external Ca2+ significantly decreased ionomycin-induced myelin and axonal spheroid formation at 2 hours but not at 1 hour after treatment. Using mice that express a neuron-specific Ca2+ indicator in spinal cord axons, we confirmed that ionomycin induced significant increases in intra-axonal Ca2+, but not in the absence of external Ca2+. Periaxonal swelling and the resultant disruption in the axo-myelinic interface often precedes and is negatively correlated with axonal spheroid formation. Pretreatment with YM58483 (500 nM), a well-established blocker of store-operated Ca2+ entry, significantly decreased myelin injury and axonal spheroid formation. Collectively, these data reveal that ionomycin-induced depletion of internal Ca2+ stores and subsequent external Ca2+ entry through store-operated Ca2+ entry contributes to pathological changes in myelin and axonal spheroid formation, providing new targets to protect central myelinated fibers.
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Affiliation(s)
- Spencer Ames
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - Kia Adams
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - Mariah E Geisen
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center; Department of Neurological Surgery; Anatomical Sciences and Neurobiology; Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY, USA
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Khananshvili D. Neuronal and astrocyte NCX isoform/splice variants: How do they participate in Na + and Ca 2+ signalling? Cell Calcium 2023; 116:102818. [PMID: 37918135 DOI: 10.1016/j.ceca.2023.102818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 10/20/2023] [Accepted: 10/22/2023] [Indexed: 11/04/2023]
Abstract
NCX1, NCX2, and NCX3 gene isoforms and their splice variants are characteristically expressed in different regions of the brain. The tissue-specific splice variants of NCX1-3 isoforms show specific expression profiles in neurons and astrocytes, whereas the relevant NCX isoform/splice variants exhibit diverse allosteric modes of Na+- and Ca2+-dependent regulation. In general, overexpression of NCX1-3 genes leads to neuroprotective effects, whereas their ablation gains the opposite results. At this end, the partial contributions of NCX isoform/splice variants to neuroprotective effects remain unresolved. The glutamate-dependent Na+ entry generates Na+ transients (in response to neuronal cell activities), whereas the Na+-driven Ca2+ entry (through the reverse NCX mode) raises Ca2+ transients. This special mode of signal coupling translates Na+ transients into the Ca2+ signals while being a part of synaptic neurotransmission. This mechanism is of general interest since disease-related conditions (ischemia, metabolic stress, and stroke among many others) trigger Na+ and Ca2+ overload with deadly outcomes of downstream apoptosis and excitotoxicity. The recently discovered mechanisms of NCX allosteric regulation indicate that some NCX variants might play a critical role in the dynamic coupling of Na+-driven Ca2+ entry. In contrast, the others are less important or even could be dangerous under altered conditions (e.g., metabolic stress). This working hypothesis can be tested by applying advanced experimental approaches and highly focused computational simulations. This may allow the development of structure-based blockers/activators that can selectively modulate predefined NCX variants to lessen the life-threatening outcomes of excitotoxicity, ischemia, apoptosis, metabolic deprivation, brain injury, and stroke.
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Affiliation(s)
- Daniel Khananshvili
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel.
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Li C, Lu P, Zhang L, He Y, Zhang L, Yang L, Zhang F, Kong X, Tao Q, Zhou J, Wu J, Peng T, Xie B, Jiang Y, Peng J. Apolipoprotein E Polymorphism Impacts White Matter Injury Through Microglial Phagocytosis After Experimental Subarachnoid Hemorrhage. Neuroscience 2023; 524:220-232. [PMID: 37290684 DOI: 10.1016/j.neuroscience.2023.05.020] [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: 01/26/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 06/10/2023]
Abstract
Apolipoprotein E (apoE, protein; APOE, gene), divided into three alleles of E2, E3 and E4 in humans, is associated with the progression of white matter lesion load. However, mechanism evidence has not been reported regarding the APOE genotype in early white matter injury (WMI) under subarachnoid hemorrhage (SAH) conditions. In the present study, we investigated the effects of APOE gene polymorphisms, by constructing microglial APOE3 and APOE4-specific overexpression, on WMI and underlying mechanisms of microglia phagocytosis in a mice model of SAH. A total of 167 male C57BL/6J mice (weight 22-26 g) were used. SAH and bleeding environment were induced by endovascular perforation in vivo and oxyHb in vitro, respectively. Multi-technology approaches, including immunohistochemistry, high throughput sequencing, gene editing for adeno-associated viruses, and several molecular biotechnologies were used to validate the effects of APOE polymorphisms on microglial phagocytosis and WMI after SAH. Our results revealed that APOE4 significantly aggravated the WMI and decreased neurobehavioral function by impairing microglial phagocytosis after SAH. Indicators negatively associated with microglial phagocytosis increased like CD16, CD86 and the ratio of CD16/CD206, while the indicators positively associated with microglial phagocytosis decreased like Arg-1 and CD206. The increased ROS and aggravating mitochondrial damage demonstrated that the damaging effects of APOE4 in SAH may be associated with microglial oxidative stress-dependent mitochondrial damage. Inhibiting mitochondrial oxidative stress by Mitoquinone (mitoQ) can enhance the phagocytic function of microglia. In conclusion, anti-oxidative stress and phagocytosis protection may serve as promising treatments in the management of SAH.
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Affiliation(s)
- Chaojie Li
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Peng Lu
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Lihan Zhang
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Yijing He
- Institute of Epigenetics and Brain Science, Southwest Medical University, Luzhou 646000, China
| | - Lifang Zhang
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Sichuan Clinical Research Center for Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Lei Yang
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Fan Zhang
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Xi Kong
- Institute of Epigenetics and Brain Science, Southwest Medical University, Luzhou 646000, China
| | - Qianke Tao
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Jian Zhou
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Sichuan Clinical Research Center for Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Jinpeng Wu
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Tangming Peng
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China
| | - Bingqing Xie
- Institute of Epigenetics and Brain Science, Southwest Medical University, Luzhou 646000, China
| | - Yong Jiang
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Laboratory of Neurological Diseases and Brain Function, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Institute of Epigenetics and Brain Science, Southwest Medical University, Luzhou 646000, China.
| | - Jianhua Peng
- Department of Neurosurgery, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Laboratory of Neurological Diseases and Brain Function, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China; Institute of Epigenetics and Brain Science, Southwest Medical University, Luzhou 646000, China; Academician (Expert) Workstation of Sichuan Province, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, China.
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Bai X, Zhao N, Koupourtidou C, Fang LP, Schwarz V, Caudal LC, Zhao R, Hirrlinger J, Walz W, Bian S, Huang W, Ninkovic J, Kirchhoff F, Scheller A. In the mouse cortex, oligodendrocytes regain a plastic capacity, transforming into astrocytes after acute injury. Dev Cell 2023:S1534-5807(23)00192-2. [PMID: 37220747 DOI: 10.1016/j.devcel.2023.04.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/16/2023] [Accepted: 04/25/2023] [Indexed: 05/25/2023]
Abstract
Acute brain injuries evoke various response cascades directing the formation of the glial scar. Here, we report that acute lesions associated with hemorrhagic injuries trigger a re-programming of oligodendrocytes. Single-cell RNA sequencing highlighted a subpopulation of oligodendrocytes activating astroglial genes after acute brain injuries. By using PLP-DsRed1/GFAP-EGFP and PLP-EGFPmem/GFAP-mRFP1 transgenic mice, we visualized this population of oligodendrocytes that we termed AO cells based on their concomitant activity of astro- and oligodendroglial genes. By fate mapping using PLP- and GFAP-split Cre complementation and repeated chronic in vivo imaging with two-photon laser-scanning microscopy, we observed the conversion of oligodendrocytes into astrocytes via the AO cell stage. Such conversion was promoted by local injection of IL-6 and was diminished by IL-6 receptor-neutralizing antibody as well as by inhibiting microglial activation with minocycline. In summary, our findings highlight the plastic potential of oligodendrocytes in acute brain trauma due to microglia-derived IL-6.
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Affiliation(s)
- Xianshu Bai
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany.
| | - Na Zhao
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany
| | - Christina Koupourtidou
- Department of Cell Biology and Anatomy, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany; Institute of Stem Cell Research, Helmholtz Zentrum Munich, 85764 Neuherberg-Munich, Germany
| | - Li-Pao Fang
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany
| | - Veronika Schwarz
- Department of Cell Biology and Anatomy, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany; Institute of Stem Cell Research, Helmholtz Zentrum Munich, 85764 Neuherberg-Munich, Germany
| | - Laura C Caudal
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany
| | - Renping Zhao
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany
| | - Johannes Hirrlinger
- Carl-Ludwig-Institute for Physiology, Leipzig University, 04103 Leipzig, Germany; Department of Neurogenetics, Max-Planck-Institute for Multidisciplinary Sciences, 37075 Göttingen, Germany
| | - Wolfgang Walz
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany; Department of Psychiatry, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada
| | - Shan Bian
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, 200092 Shanghai, China; Frontier Science Center for Stem Cell Research, Tongji University, 200092 Shanghai, China
| | - Wenhui Huang
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany
| | - Jovica Ninkovic
- Department of Cell Biology and Anatomy, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany; Institute of Stem Cell Research, Helmholtz Zentrum Munich, 85764 Neuherberg-Munich, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany; Experimental Research Center for Normal and Pathological Aging, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine, University of Saarland, 66421 Homburg, Germany.
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Ferreira RS, Ribeiro PR, Silva JHCE, Hoppe JB, de Almeida MMA, de Lima Ferreira BC, Andrade GB, de Souza SB, Ferdandez LG, de Fátima Dias Costa M, Salbego CG, Rivera AD, Longoni A, de Assis AM, Pieropan F, Moreira JCF, Costa SL, Butt AM, da Silva VDA. Amburana cearensis seed extract stimulates astrocyte glutamate homeostatic mechanisms in hippocampal brain slices and protects oligodendrocytes against ischemia. BMC Complement Med Ther 2023; 23:154. [PMID: 37170258 PMCID: PMC10173544 DOI: 10.1186/s12906-023-03959-0] [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: 09/27/2022] [Accepted: 04/13/2023] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND Stroke is a leading cause of death and disability worldwide. A major factor in brain damage following ischemia is excitotoxicity caused by elevated levels of the neurotransmitter glutamate. In the brain, glutamate homeostasis is a primary function of astrocytes. Amburana cearensis has long been used in folk medicine and seed extract obtained with dichloromethane (EDAC) have previously been shown to exhibit cytoprotective activity in vitro. The aim of the present study was to analyse the activity of EDAC in hippocampal brain slices. METHODS We prepared a dichloromethane extract (EDAC) from A. cearensis seeds and characterized the chemical constituents by 1H and 13C-NMR. Hippocampal slices from P6-8 or P90 Wistar rats were used for cell viability assay or glutamate uptake test. Hippocampal slices from P10-12 transgenic mice SOX10-EGFP and GFAP-EGFP and immunofluorescence for GS, GLAST and GLT1 were used to study oligodendrocytes and astrocytes. RESULTS Astrocytes play a critical role in glutamate homeostasis and we provide immunohistochemical evidence that in excitotoxicity EDAC increased expression of glutamate transporters and glutamine synthetase, which is essential for detoxifying glutamate. Next, we directly examined astrocytes using transgenic mice in which glial fibrillary acidic protein (GFAP) drives expression of enhanced green fluorescence protein (EGFP) and show that glutamate excitotoxicity caused a decrease in GFAP-EGFP and that EDAC protected against this loss. This was examined further in the oxygen-glucose deprivation (OGD) model of ischemia, where EDAC caused an increase in astrocytic process branching, resulting in an increase in GFAP-EGFP. Using SOX10-EGFP reporter mice, we show that the acute response of oligodendrocytes to OGD in hippocampal slices is a marked loss of their processes and EDAC protected oligodendrocytes against this damage. CONCLUSION This study provides evidence that EDAC is cytoprotective against ischemia and glutamate excitotoxicity by modulating astrocyte responses and stimulating their glutamate homeostatic mechanisms.
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Affiliation(s)
- Rafael Short Ferreira
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK
| | - Paulo Roberto Ribeiro
- Metabolomics Research Group, Department of Organic Chemistry, Chemistry Institute, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Juliana Helena Castro E Silva
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK
| | - Juliana Bender Hoppe
- Department of Biochemistry, Institute of Basic Health Sciences, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil
| | - Monique Marylin Alves de Almeida
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK
| | - Beatriz Correia de Lima Ferreira
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
| | - Gustavo Borges Andrade
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
| | - Suzana Braga de Souza
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
| | - Luzimar Gonzaga Ferdandez
- Biochemistry, Biotechnology and Bioproducts Laboratory, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Maria de Fátima Dias Costa
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil
| | - Christianne Gazzana Salbego
- Department of Biochemistry, Institute of Basic Health Sciences, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil
| | - Andrea Domenico Rivera
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK
| | - Aline Longoni
- Health Sciences Centre, Post-Graduate Program in Health and Behaviour, Catholic University of Pelotas, Pelotas, Brazil
| | - Adriano Martimbianco de Assis
- Health Sciences Centre, Post-Graduate Program in Health and Behaviour, Catholic University of Pelotas, Pelotas, Brazil
| | - Francesca Pieropan
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK
| | - José Cláudio Fonseca Moreira
- Department of Biochemistry, Institute of Basic Health Sciences, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil
| | - Silvia Lima Costa
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil.
| | - Arthur Morgan Butt
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK.
| | - Victor Diogenes Amaral da Silva
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia - UFBA, Salvador, Bahia, 40110-902, Brazil.
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK.
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Stirling DP. Potential physiological and pathological roles for axonal ryanodine receptors. Neural Regen Res 2023; 18:756-759. [PMID: 36204832 PMCID: PMC9700104 DOI: 10.4103/1673-5374.354512] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/02/2022] [Accepted: 06/23/2022] [Indexed: 11/04/2022] Open
Abstract
Clinical disability following trauma or disease to the spinal cord often involves the loss of vital white matter elements including axons and glia. Although excessive Ca2+ is an established driver of axonal degeneration, therapeutically targeting externally sourced Ca2+ to date has had limited success in both basic and clinical studies. Contributing factors that may underlie this limited success include the complexity of the many potential sources of Ca2+ entry and the discovery that axons also contain substantial amounts of stored Ca2+ that if inappropriately released could contribute to axonal demise. Axonal Ca2+ storage is largely accomplished by the axoplasmic reticulum that is part of a continuous network of the endoplasmic reticulum that provides a major sink and source of intracellular Ca2+ from the tips of dendrites to axonal terminals. This "neuron-within-a-neuron" is positioned to rapidly respond to diverse external and internal stimuli by amplifying cytosolic Ca2+ levels and generating short and long distance regenerative Ca2+ waves through Ca2+ induced Ca2+ release. This review provides a glimpse into the molecular machinery that has been implicated in regulating ryanodine receptor mediated Ca2+ release in axons and how dysregulation and/or overstimulation of these internodal axonal signaling nanocomplexes may directly contribute to Ca2+-dependent axonal demise. Neuronal ryanodine receptors expressed in dendrites, soma, and axonal terminals have been implicated in synaptic transmission and synaptic plasticity, but a physiological role for internodal localized ryanodine receptors remains largely obscure. Plausible physiological roles for internodal ryanodine receptors and such an elaborate internodal binary membrane signaling network in axons will also be discussed.
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Affiliation(s)
- David P. Stirling
- Kentucky Spinal Cord Injury Research Center and Departments of Neurological Surgery, Anatomical Sciences and Neurobiology, Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY, USA
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8
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Huang Y, Omorou M, Gao M, Mu C, Xu W, Xu H. Hydrogen sulfide and its donors for the treatment of cerebral ischaemia-reperfusion injury: A comprehensive review. Biomed Pharmacother 2023; 161:114506. [PMID: 36906977 DOI: 10.1016/j.biopha.2023.114506] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
As an endogenous gas signalling molecule, hydrogen sulfide (H2S) is frequently present in a variety of mammals and plays a significant role in the cardiovascular and nervous systems. Reactive oxygen species (ROS) are produced in large quantities as a result of cerebral ischaemia-reperfusion, which is a very serious class of cerebrovascular diseases. ROS cause oxidative stress and induce specific gene expression that results in apoptosis. H2S reduces cerebral ischaemia-reperfusion-induced secondary injury via anti-oxidative stress injury, suppression of the inflammatory response, inhibition of apoptosis, attenuation of cerebrovascular endothelial cell injury, modulation of autophagy, and antagonism of P2X7 receptors, and it plays an important biological role in other cerebral ischaemic injury events. Despite the many limitations of the hydrogen sulfide therapy delivery strategy and the difficulty in controlling the ideal concentration, relevant experimental evidence demonstrating that H2S plays an excellent neuroprotective role in cerebral ischaemia-reperfusion injury (CIRI). This paper examines the synthesis and metabolism of the gas molecule H2S in the brain as well as the molecular mechanisms of H2S donors in cerebral ischaemia-reperfusion injury and possibly other unknown biological functions. With the active development in this field, it is expected that this review will assist researchers in their search for the potential value of hydrogen sulfide and provide new ideas for preclinical trials of exogenous H2S.
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Affiliation(s)
- Yiwei Huang
- Basic Medical College, Jiamusi University, Jiamusi 154007, Heilongjiang, China; Key Laboratory of Microecology-Immune Regulatory Network and Related Diseases, Jiamusi 154007, Heilongjiang, China.
| | - Moussa Omorou
- Key Laboratory of Microecology-Immune Regulatory Network and Related Diseases, Jiamusi 154007, Heilongjiang, China; Basic Medical College, Jiamusi University, Jiamusi 154007, Heilongjiang, China.
| | - Meng Gao
- Key Laboratory of Microecology-Immune Regulatory Network and Related Diseases, Jiamusi 154007, Heilongjiang, China; Basic Medical College, Jiamusi University, Jiamusi 154007, Heilongjiang, China.
| | - Chenxi Mu
- Key Laboratory of Microecology-Immune Regulatory Network and Related Diseases, Jiamusi 154007, Heilongjiang, China; Basic Medical College, Jiamusi University, Jiamusi 154007, Heilongjiang, China.
| | - Weijing Xu
- School of Public Health, Jiamusi University, Jiamusi 154007, Heilongjiang, China.
| | - Hui Xu
- Key Laboratory of Microecology-Immune Regulatory Network and Related Diseases, Jiamusi 154007, Heilongjiang, China.
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9
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He Y, Chen X, Wu M, Hou X, Zhou Z. What type of cell death occurs in chronic cerebral hypoperfusion? A review focusing on pyroptosis and its potential therapeutic implications. Front Cell Neurosci 2023; 17:1073511. [PMID: 36937182 PMCID: PMC10017988 DOI: 10.3389/fncel.2023.1073511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/31/2023] [Indexed: 03/06/2023] Open
Abstract
Chronic cerebral hypoperfusion (CCH) is a major global disease with chronic cerebral blood flow reduction. It is also the main cause of cognitive impairment and neurodegenerative diseases. Pyroptosis, a novel form of cell death, is characterized by the rupture of the cell membrane and the release of pro-inflammatory mediators. In recent years, an increasing number of studies have identified the involvement of pyroptosis and its mediated inflammatory response in the pathological process of CCH. Therefore, preventing the activation of pyroptosis following CCH is beneficial to inhibit the inflammatory cascade and reduce brain injury. In this review, we discuss the research progress on the relationship between pyroptosis and CCH, in order to provide a reference for research in related fields.
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Affiliation(s)
- Yuxuan He
- Department of Neurology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
- Department of Neurology, School of Medicine, Chongqing University, Chongqing, China
| | - Xi Chen
- Department of Neurology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Min Wu
- Department of Neurology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xianhua Hou
- Department of Neurology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
- *Correspondence: Xianhua Hou Zhenhua Zhou
| | - Zhenhua Zhou
- Department of Neurology, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing, China
- *Correspondence: Xianhua Hou Zhenhua Zhou
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10
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Role of NAD + and FAD in Ischemic Stroke Pathophysiology: An Epigenetic Nexus and Expanding Therapeutic Repertoire. Cell Mol Neurobiol 2022:10.1007/s10571-022-01287-4. [PMID: 36180651 DOI: 10.1007/s10571-022-01287-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 09/15/2022] [Indexed: 11/03/2022]
Abstract
The redox coenzymes viz., oxidized β-nicotinamide adenine dinucleotide (NAD+) and flavin adenine dinucleotide (FAD) by way of generation of optimal reducing power and cellular energy currency (ATP), control a staggering array of metabolic reactions. The prominent cellular contenders for NAD+ utilization, inter alia, are sirtuins (SIRTs) and poly(ADP-ribose) polymerase (PARP-1), which have been significantly implicated in ischemic stroke (IS) pathogenesis. NAD+ and FAD are also two crucial epigenetic enzyme-required metabolites mediating histone deacetylation and poly(ADP-ribosyl)ation through SIRTs and PARP-1 respectively, and demethylation through FAD-mediated lysine specific demethylase activity. These enzymes and post-translational modifications impinge on the components of neurovascular unit, primarily neurons, and elicit diverse functional upshots in an ischemic brain. These could be circumstantially linked with attendant cognitive deficits and behavioral outcomes in post-stroke epoch. Parsing out the contribution of NAD+/FAD-synthesizing and utilizing enzymes towards epigenetic remodeling in IS setting, together with their cognitive and behavioral associations, combined with possible therapeutic implications will form the crux of this review.
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11
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Wang K, Wang C, Chen D, Huang Y, Li J, Wei P, Shi Z, Zhang Y, Gao Y. The role of microglial/macrophagic salt-inducible kinase 3 on normal and excessive phagocytosis after transient focal cerebral ischemia. Cell Mol Life Sci 2022; 79:439. [PMID: 35864266 PMCID: PMC9304053 DOI: 10.1007/s00018-022-04465-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 06/17/2022] [Accepted: 07/03/2022] [Indexed: 11/28/2022]
Abstract
Previous studies suggested that anti-inflammatory microglia/macrophages (Mi/MΦ) play a role in “normal phagocytosis,” which promoted the rapid clearance of necrotic substances and apoptotic cells. More recently, a few studies have found that Mi/MΦ also play a role in “pathological phagocytosis” in the form of excessive or reduced phagocytosis, thereby worsening damage induced by CNS diseases. However, the underlying mechanisms and the Mi/MΦ subtypes related to this pathological phagocytosis are still unknown. Salt-inducible kinase 3 (SIK3), a member of the 5’ adenosine monophosphate-activated protein kinase (AMPK) family, has been shown to regulate inflammation in several peripheral diseases. Whether SIK3 also regulates the inflammatory response in CNS diseases is currently unknown. Therefore, in this study, we created a transgenic tamoxifen-induced Mi/MΦ-specific SIK3 conditional knockout (SIK3-cKO) mouse to examine SIK3’s role in phagocytotic function induced by transient focal cerebral ischemia (tFCI). By single-cell RNA-seq, we found the pro-inflammatory Mi/MΦ phenotype performed an excessive phagocytotic function, but the anti-inflammatory Mi/MΦ phenotype performed a normal phagocytotic function. We found that SIK3-cKO caused Mi/MΦ heterogenization from the transitional phenotype to the anti-inflammatory phenotype after tFCI. This phenotypic shift corresponded with enhanced phagocytosis of both apoptotic and live neurons. Interestingly, SIK3-cKO enhanced normal phagocytosis of myelin debris but attenuating excessive phagocytosis of non-damaged myelin sheath, thereby protecting white matter integrity after tFCI. CD16, a pro-inflammation marker, was decreased significantly by SIK3-cKO and correlated with “excessive phagocytosis.” SIK3-cKO promoted long-term recovery of white matter function and neurological function as assessed with electrophysiological compound action potential (CAPs) and behavioral analysis. This study is the first to show a role of SIK3 in Mi/MΦ phagocytosis in CNS diseases, and reveals that promoting Mi/MΦ anti-inflammatory heterogenization inhibits “excessive phagocytosis” of live cells and facilitates “normal phagocytosis” of apoptotic cells. Therefore, inhibition of SIK3 in Mi/MΦ may be a potential therapeutic target in stroke and other CNS diseases with accompanying white matter destruction.
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Affiliation(s)
- Ke Wang
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Chenran Wang
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Di Chen
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Yichen Huang
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Jiaying Li
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Pengju Wei
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Ziyu Shi
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Yue Zhang
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology, MOE Frontier Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China.
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12
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Beeraka NM, Vikram PRH, Greeshma MV, Uthaiah CA, Huria T, Liu J, Kumar P, Nikolenko VN, Bulygin KV, Sinelnikov MY, Sukocheva O, Fan R. Recent Investigations on Neurotransmitters' Role in Acute White Matter Injury of Perinatal Glia and Pharmacotherapies-Glia Dynamics in Stem Cell Therapy. Mol Neurobiol 2022; 59:2009-2026. [PMID: 35041139 DOI: 10.1007/s12035-021-02700-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 12/10/2021] [Indexed: 02/05/2023]
Abstract
Periventricular leukomalacia (PVL) and cerebral palsy are two neurological disease conditions developed from the premyelinated white matter ischemic injury (WMI). The significant pathophysiology of these diseases is accompanied by the cognitive deficits due to the loss of function of glial cells and axons. White matter makes up 50% of the brain volume consisting of myelinated and non-myelinated axons, glia, blood vessels, optic nerves, and corpus callosum. Studies over the years have delineated the susceptibility of white matter towards ischemic injury especially during pregnancy (prenatal, perinatal) or immediately after child birth (postnatal). Impairment in membrane depolarization of neurons and glial cells by ischemia-invoked excitotoxicity is mediated through the overactivation of NMDA receptors or non-NMDA receptors by excessive glutamate influx, calcium, or ROS overload and has been some of the well-studied molecular mechanisms conducive to the injury of white matter. Expression of glutamate receptors (GluR) and transporters (GLT1, EACC1, and GST) has significant influence in glial and axonal-mediated injury of premyelinated white matter during PVL and cerebral palsy. Predominantly, the central premyelinated axons express extensive levels of functional NMDA GluR receptors to confer ischemic injury to premyelinated white matter which in turn invoke defects in neural plasticity. Several underlying molecular mechanisms are yet to be unraveled to delineate the complete pathophysiology of these prenatal neurological diseases for developing the novel therapeutic modalities to mitigate pathophysiology and premature mortality of newborn babies. In this review, we have substantially discussed the above multiple pathophysiological aspects of white matter injury along with glial dynamics, and the pharmacotherapies including recent insights into the application of MSCs as therapeutic modality in treating white matter injury.
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Affiliation(s)
- Narasimha M Beeraka
- Cancer Center, Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450000, People's Republic of China
- Center of Excellence in Molecular Biology and Regenerative Medicine (CEMR), Department of Biochemistry, JSS Medical College, JSS Academy of Higher Education and Research (JSS AHER), Mysuru, Karnataka, India
- Department of Human Anatomy, I. M. Sechenov First Moscow State Medical University (Sechenov University), St. Trubetskaya, 8, bld. 2, Moscow, 119991, Russia
| | - P R Hemanth Vikram
- Department of Pharmaceutical Chemistry, JSS Pharmacy College, Mysuru, Karnataka, India
| | - M V Greeshma
- Center of Excellence in Molecular Biology and Regenerative Medicine (CEMR), Department of Biochemistry, JSS Medical College, JSS Academy of Higher Education and Research (JSS AHER), Mysuru, Karnataka, India
| | - Chinnappa A Uthaiah
- Center of Excellence in Molecular Biology and Regenerative Medicine (CEMR), Department of Biochemistry, JSS Medical College, JSS Academy of Higher Education and Research (JSS AHER), Mysuru, Karnataka, India
| | - Tahani Huria
- Faculty of Medicine, Benghazi University, Benghazi, Libya
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, LE1 7RH, UK
| | - Junqi Liu
- Cancer Center, Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450000, People's Republic of China
| | - Pramod Kumar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER-Guwahati), SilaKatamur (Halugurisuk), Changsari, Kamrup, 781101, Assam, India
| | - Vladimir N Nikolenko
- Department of Human Anatomy, I. M. Sechenov First Moscow State Medical University (Sechenov University), St. Trubetskaya, 8, bld. 2, Moscow, 119991, Russia
- Department of Normal and Topographic Anatomy, Faculty of Fundamental Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Kirill V Bulygin
- Department of Human Anatomy, I. M. Sechenov First Moscow State Medical University (Sechenov University), St. Trubetskaya, 8, bld. 2, Moscow, 119991, Russia
| | - Mikhail Y Sinelnikov
- Department of Human Anatomy, I. M. Sechenov First Moscow State Medical University (Sechenov University), St. Trubetskaya, 8, bld. 2, Moscow, 119991, Russia
- Research Institute of Human Morphology, 3 Tsyurupy Street, Moscow, 117418, Russian Federation
| | - Olga Sukocheva
- Discipline of Health Sciences, College of Nursing and Health Sciences, Flinders University, Bedford Park, South Australia, 5042, Australia
| | - Ruitai Fan
- Cancer Center, Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450000, People's Republic of China.
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13
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Peng K, Koduri S, Ye F, Yang J, Keep RF, Xi G, Hua Y. A timeline of oligodendrocyte death and proliferation following experimental subarachnoid hemorrhage. CNS Neurosci Ther 2022; 28:842-850. [PMID: 35150055 PMCID: PMC9062564 DOI: 10.1111/cns.13812] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 12/15/2022] Open
Abstract
AIMS White matter (WM) injury is a critical factor associated with worse outcomes following subarachnoid hemorrhage (SAH). However, the detailed pathological changes are not completely understood. This study investigates temporal changes in the corpus callosum (CC), including WM edema and oligodendrocyte death after SAH, and the role of lipocalin-2 (LCN2) in those changes. METHODS Subarachnoid hemorrhage was induced in adult wild-type or LCN2 knockout mice via endovascular perforation. Magnetic resonance imaging was performed 4 hours, 1 day, and 8 days after SAH, and T2 hyperintensity changes within the CC were quantified to represent WM edema. Immunofluorescence staining was performed to evaluate oligodendrocyte death and proliferation. RESULTS Subarachnoid hemorrhage induced significant CC T2 hyperintensity at 4 hours and 1 day that diminished significantly by 8 days post-procedure. Comparing changes between the 4 hours and 1 day, each individual mouse had an increase in CC T2 hyperintensity volume. Oligodendrocyte death was observed at 4 hours, 1 day, and 8 days after SAH induction, and there was progressive loss of mature oligodendrocytes, while immature oligodendrocytes/oligodendrocyte precursor cells (OPCs) proliferated back to baseline by Day 8 after SAH. Moreover, LCN2 knockout attenuated WM edema and oligodendrocyte death at 24 hours after SAH. CONCLUSIONS Subarachnoid hemorrhage leads to T2 hyperintensity change within the CC, which indicates WM edema. Oligodendrocyte death was observed in the CC within 1 day of SAH, with a partial recovery by Day 8. SAH-induced WM injury was alleviated in an LCN2 knockout mouse model.
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Affiliation(s)
- Kang Peng
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA,Department of NeurosurgeryXiangya HospitalCentral South UniversityChangshaChina
| | - Sravanthi Koduri
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Fenghui Ye
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Jinting Yang
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Richard F. Keep
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Guohua Xi
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
| | - Ya Hua
- Department of NeurosurgeryUniversity of MichiganAnn ArborMichiganUSA
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14
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Xu Y, Tian Y, Wang Y, Xu L, Song G, Wu Q, Wang W, Xie M. Exosomes derived from astrocytes after oxygen-glucose deprivation promote differentiation and migration of oligodendrocyte precursor cells in vitro. Mol Biol Rep 2021; 48:5473-5484. [PMID: 34312743 DOI: 10.1007/s11033-021-06557-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 07/09/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Excessive release of glutamate, oxidative stress, inflammation after ischemic brain injury can lead to demyelination. Astrocytes participate in the maturation and differentiation of oligodendrocyte precursor cells (OPCs), and play multiple roles in the process of demyelination and remyelination. Here, we studied the role of Astrocyte-derived exosomes (AS-Exo) under ischemic conditions in proliferation, differentiation and migration of OPCs in vitro. METHODS AND RESULTS Exosomes were collected from astrocytes supernatant by differential centrifugation from control astrocytes (CTexo), mild hypoxia astrocytes (O2R24exo) which were applied oxygen-glucose deprivation for 2 h and reperfusion for 24 h (OGD2hR24h) and severe hypoxia astrocytes (O4R24exo) which were applied oxygen-glucose deprivation for 4 h and reperfusion for 24 h (OGD4hR24h). Exosomes (20 µg/ml) were co-cultured with OPCs for 24 h and their proliferation, differentiation and migration were detected. The results showed that AS-Exo under severe hypoxia (O4R24exo) inhibit the proliferation of OPCs. Meanwhile, all exosomes from three groups can promote OPCs differentiation and migration. Compared to control, the expressions of MAG and MBP, markers of mature oligodendrocytes, were significantly increased in AS-Exo treatment groups. AS-Exo treatment significantly increased chemotaxis for OPCs. CONCLUSIONS AS-Exo improve OPCs' differentiation and migration, whereas AS-Exo with severe hypoxic precondition suppress OPCs' proliferation. AS-Exo may be a potential therapeutic target for myelin regeneration and repair in white matter injury or other demyelination related diseases.
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Affiliation(s)
- Yaping Xu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China.,Department of Neurology, Xiangyang No. 1 People's Hospital, Hubei University of Medicine, Xiangyang, 441000, People's Republic of China
| | - Yeye Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China
| | - Yao Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China
| | - Li Xu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China
| | - Guini Song
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China
| | - Qiao Wu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China.,Key Laboratory of Neurological Diseases of Chinese Ministry of Education, The School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Minjie Xie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1095 Jiefang Avenue, Wuhan, 430030, People's Republic of China. .,Key Laboratory of Neurological Diseases of Chinese Ministry of Education, The School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
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15
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van Putten MJ, Fahlke C, Kafitz KW, Hofmeijer J, Rose CR. Dysregulation of Astrocyte Ion Homeostasis and Its Relevance for Stroke-Induced Brain Damage. Int J Mol Sci 2021; 22:5679. [PMID: 34073593 PMCID: PMC8198632 DOI: 10.3390/ijms22115679] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/21/2021] [Accepted: 05/22/2021] [Indexed: 12/14/2022] Open
Abstract
Ischemic stroke is a leading cause of mortality and chronic disability. Either recovery or progression towards irreversible failure of neurons and astrocytes occurs within minutes to days, depending on remaining perfusion levels. Initial damage arises from energy depletion resulting in a failure to maintain homeostasis and ion gradients between extra- and intracellular spaces. Astrocytes play a key role in these processes and are thus central players in the dynamics towards recovery or progression of stroke-induced brain damage. Here, we present a synopsis of the pivotal functions of astrocytes at the tripartite synapse, which form the basis of physiological brain functioning. We summarize the evidence of astrocytic failure and its consequences under ischemic conditions. Special emphasis is put on the homeostasis and stroke-induced dysregulation of the major monovalent ions, namely Na+, K+, H+, and Cl-, and their involvement in maintenance of cellular volume and generation of cerebral edema.
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Affiliation(s)
- Michel J.A.M. van Putten
- Department of Clinical Neurophysiology, University of Twente, 7522 NB Enschede, The Netherlands; (M.J.A.M.v.P.); (J.H.)
| | - Christoph Fahlke
- Institut für Biologische Informationsprozesse, Molekular-und Zellphysiologie (IBI-1), Forschungszentrum Jülich, 52425 Jülich, Germany;
| | - Karl W. Kafitz
- Institute of Neurobiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Jeannette Hofmeijer
- Department of Clinical Neurophysiology, University of Twente, 7522 NB Enschede, The Netherlands; (M.J.A.M.v.P.); (J.H.)
| | - Christine R. Rose
- Institute of Neurobiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
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16
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Rivera AD, Chacon-De-La-Rocha I, Pieropan F, Papanikolau M, Azim K, Butt AM. Keeping the ageing brain wired: a role for purine signalling in regulating cellular metabolism in oligodendrocyte progenitors. Pflugers Arch 2021; 473:775-783. [PMID: 33712969 PMCID: PMC8076121 DOI: 10.1007/s00424-021-02544-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/04/2021] [Accepted: 02/19/2021] [Indexed: 02/07/2023]
Abstract
White matter (WM) is a highly prominent feature in the human cerebrum and is comprised of bundles of myelinated axons that form the connectome of the brain. Myelin is formed by oligodendrocytes and is essential for rapid neuronal electrical communication that underlies the massive computing power of the human brain. Oligodendrocytes are generated throughout life by oligodendrocyte precursor cells (OPCs), which are identified by expression of the chondroitin sulphate proteoglycan NG2 (Cspg4), and are often termed NG2-glia. Adult NG2+ OPCs are slowly proliferating cells that have the stem cell-like property of self-renewal and differentiation into a pool of 'late OPCs' or 'differentiation committed' OPCs(COPs) identified by specific expression of the G-protein-coupled receptor GPR17, which are capable of differentiation into myelinating oligodendrocytes. In the adult brain, these reservoirs of OPCs and COPs ensure rapid myelination of new neuronal connections formed in response to neuronal signalling, which underpins learning and cognitive function. However, there is an age-related decline in myelination that is associated with a loss of neuronal function and cognitive decline. The underlying causes of myelin loss in ageing are manifold, but a key factor is the decay in OPC 'stemness' and a decline in their replenishment of COPs, which results in the ultimate failure of myelin regeneration. These changes in ageing OPCs are underpinned by dysregulation of neuronal signalling and OPC metabolic function. Here, we highlight the role of purine signalling in regulating OPC self-renewal and the potential importance of GPR17 and the P2X7 receptor subtype in age-related changes in OPC metabolism. Moreover, age is the main factor in the failure of myelination in chronic multiple sclerosis and myelin loss in Alzheimer's disease, hence understanding the importance of purine signalling in OPC regeneration and myelination is critical for developing new strategies for promoting repair in age-dependent neuropathology.
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Affiliation(s)
- Andrea D Rivera
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK
- Department of Neuroscience, Institute of Human Anatomy, University of Padua, Padua, Italy
| | | | - Francesca Pieropan
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK
| | - Maria Papanikolau
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK
| | - Kasum Azim
- Department of Neurology, Neuroregeneration, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Arthur M Butt
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK.
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17
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O'Carroll SJ, Cook WH, Young D. AAV Targeting of Glial Cell Types in the Central and Peripheral Nervous System and Relevance to Human Gene Therapy. Front Mol Neurosci 2021; 13:618020. [PMID: 33505247 PMCID: PMC7829478 DOI: 10.3389/fnmol.2020.618020] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/11/2020] [Indexed: 12/12/2022] Open
Abstract
Different glial cell types are found throughout the central (CNS) and peripheral nervous system (PNS), where they have important functions. These cell types are also involved in nervous system pathology, playing roles in neurodegenerative disease and following trauma in the brain and spinal cord (astrocytes, microglia, oligodendrocytes), nerve degeneration and development of pain in peripheral nerves (Schwann cells, satellite cells), retinal diseases (Müller glia) and gut dysbiosis (enteric glia). These cell type have all been proposed as potential targets for treating these conditions. One approach to target these cell types is the use of gene therapy to modify gene expression. Adeno-associated virus (AAV) vectors have been shown to be safe and effective in targeting cells in the nervous system and have been used in a number of clinical trials. To date, a number of studies have tested the use of different AAV serotypes and cell-specific promoters to increase glial cell tropism and expression. However, true glial-cell specific targeting for a particular glial cell type remains elusive. This review provides an overview of research into developing glial specific gene therapy and discusses some of the issues that still need to be addressed to make glial cell gene therapy a clinical reality.
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Affiliation(s)
- Simon J O'Carroll
- Spinal Cord Injury Research Group, Department of Anatomy and Medical Imaging, School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - William H Cook
- Molecular Neurotherapeutics Group, Department of Pharmacology and Clinical Pharmacology, School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - Deborah Young
- Molecular Neurotherapeutics Group, Department of Pharmacology and Clinical Pharmacology, School of Medical Sciences, University of Auckland, Auckland, New Zealand
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18
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Zhao C, Zhao S, Guan M, Cheng X, Wang H, Liu C, Zhong S, Zhou Z, Liang Y. Forced forelimb use following stroke enhances oligodendrogenesis and functional recovery in the rat. Brain Res 2020; 1746:147016. [PMID: 32679116 DOI: 10.1016/j.brainres.2020.147016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/23/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022]
Abstract
Forced limb use, which forces the use of the impaired arm following stroke, improves functional recovery. The study was designed to investigate the mechanisms of recovery underlying forced impaired limbuse. Furthermore, forced unimpaired arm use was also performed in order to explore its effect on functional behavior. We hypothesized that forced forelimb use could improve functional recovery in rats that have had an experimentally induced ischemic stroke, through promoting the recruitment and differentiation of the oligodendrocyte progenitor cells (OPCs). Indeed the proliferation of Olig2 and NG2 positive cells, as well as the expression of myelin basic protein (MBP)were increased in the perilesional striatum, whereas quantitative changes of Olig2+ and NG2+ oligodendrocyte progenitor cells was not observed in the subventricular zone. Through comparing rats forced to rely on affected or unaffected forelimb, the results demonstrated that forced impaired limb use boosted functional recovery. At the same time forced unimpaired limb use deteriorated limb movement of injured side. In addition, the expression of NogoA is reduced, when the injured limb was used more, suggesting that it played a role in the repair of white matter.
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Affiliation(s)
- Chuansheng Zhao
- The First Hospital of China Medical University, Shenyang, China.
| | - Shanshan Zhao
- The First Hospital of China Medical University, Shenyang, China.
| | - Meiting Guan
- The First Hospital of China Medical University, Shenyang, China.
| | - Xi Cheng
- The First Hospital of China Medical University, Shenyang, China.
| | - Huibin Wang
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Chang Liu
- The First Hospital of China Medical University, Shenyang, China.
| | - Shanshan Zhong
- The First Hospital of China Medical University, Shenyang, China.
| | - Zhike Zhou
- The First Hospital of China Medical University, Shenyang, China.
| | - Yifan Liang
- The First Hospital of China Medical University, Shenyang, China.
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19
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Orem BC, Rajaee A, Stirling DP. IP 3R-mediated intra-axonal Ca 2+ release contributes to secondary axonal degeneration following contusive spinal cord injury. Neurobiol Dis 2020; 146:105123. [PMID: 33011333 DOI: 10.1016/j.nbd.2020.105123] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/15/2020] [Accepted: 09/28/2020] [Indexed: 01/11/2023] Open
Abstract
Secondary axonal loss contributes to the persistent functional disability following trauma. Consequently, preserving axons following spinal cord injury (SCI) is a major therapeutic goal to improve neurological outcome; however, the complex molecular mechanisms that mediate secondary axonal degeneration remain unclear. We previously showed that IP3R-mediated Ca2+ release contributes to axonal dieback and axonal loss following an ex vivo laser-induced SCI. Nevertheless, targeting IP3R in a clinically relevant in vivo model of SCI and determining its contribution to secondary axonal degeneration has yet to be explored. Here we used intravital two-photon excitation microscopy to assess the role of IP3R in secondary axonal degeneration in real-time after a contusive-SCI in vivo. To visualize Ca2+ changes specifically in spinal axons over time, adult 6-8 week-old triple transgenic Avil-Cre:Ai9:Ai95 (sensory neuron-specific expression of tdTomato and the genetic calcium indicator GCaMP6f) mice were subjected to a mild (30 kdyn) T12 contusive-SCI and received delayed treatment with the IP3R blocker 2-APB (100 μM, intrathecal delivery at 3, and 24 h following injury) or vehicle control. To determine the IP3R subtype involved, we knocked-down IP3R3 using capped phosphodiester oligonucleotides. Delayed treatment with 2-APB significantly reduced axonal spheroids, increased axonal survival, and reduced intra-axonal Ca2+ accumulation within dorsal column axons at 24 h following SCI in vivo. Additionally, knockdown of IP3R3 yielded increased axon survival 24 h post-SCI. These results suggest that IP3R-mediated Ca2+ release contributes to secondary axonal degeneration in vivo following SCI.
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Affiliation(s)
- Ben C Orem
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - Arezoo Rajaee
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Departments of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA
| | - David P Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Departments of Neurological Surgery, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, KY 40202, USA; Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY 40202, USA.
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20
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Cell Death Pathways in Ischemic Stroke and Targeted Pharmacotherapy. Transl Stroke Res 2020; 11:1185-1202. [PMID: 32219729 DOI: 10.1007/s12975-020-00806-z] [Citation(s) in RCA: 177] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 03/04/2020] [Accepted: 03/10/2020] [Indexed: 02/07/2023]
Abstract
Ischemic stroke is one of the significant causes of morbidity and mortality, affecting millions of people across the globe. Cell injury in the infarct region is an inevitable consequence of focal cerebral ischemia. Subsequent reperfusion exacerbates the harmful effect and increases the infarct volume. These cellular injuries follow either a regulated pathway involving tightly structured signaling cascades and molecularly defined effector mechanisms or a non-regulated pathway, also known as accidental cell death, where the process is biologically uncontrolled. Classical cell death pathways are long established and well reported in several articles that majorly define apoptotic cell death. A recent focus on cell death study also considers investigation on non-classical pathways that are tightly regulated, may or may not involve caspases, but non-apoptotic. Pathological cell death is a cardinal feature of different neurodegenerative diseases. Although ischemia cannot be classified as a neurodegenerative disease, it is a cerebrovascular event where the infarct region exhibits aberrant cell death. Over the past few decades, several therapeutic options have been implicated for ischemic stroke. However, their use has been hampered owing to the number of limitations that they possess. Ischemic penumbral neurons undergo apoptosis and become dysfunctional; however, they are salvageable. Thus, understanding the role of different cell death pathways is crucial to aid in the modern treatment of protecting apoptotic neurons.
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21
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Altamentova S, Rumajogee P, Hong J, Beldick SR, Park SJ, Yee A, Fehlings MG. Methylprednisolone Reduces Persistent Post-ischemic Inflammation in a Rat Hypoxia-Ischemia Model of Perinatal Stroke. Transl Stroke Res 2020; 11:1117-1136. [PMID: 32140998 DOI: 10.1007/s12975-020-00792-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/12/2020] [Accepted: 02/19/2020] [Indexed: 12/21/2022]
Abstract
In perinatal stroke, the initial injury results in a chronic inflammatory response caused by the release of proinflammatory cytokines, gliosis and microglia activation. This chronic and ongoing inflammatory response exacerbates the brain injury, often resulting in encephalopathy and cerebral palsy (CP). Using a neonatal rat model of hypoxia-ischemia (HI) at postnatal day (P)7, we demonstrated that chronic inflammation is persistent and continues into the tertiary phase of perinatal stroke and can be attenuated by the administration of methylprednisolone sodium-succinate (MPSS, 30 mg/kg), a US Food and Drug Administration (FDA) approved anti-inflammatory agent. The inflammatory response was assessed by real-time quantitative PCR and ELISA for markers of inflammation (CCL3, CCL5, IL18 and TNFα). Structural changes were evaluated by histology (LFB/H&E), while cellular changes were assessed by Iba-1, ED1, GFAP, NeuN, Olig2 and CC1 immunostaining. Functional deficits were assessed with the Cylinder test and Ladder Rung Walking test. MPSS was injected 14 days after HI insult to attenuate chronic inflammation. In neonatal conditions such as CP, P21 is a clinically relevant time-point in rodents, corresponding developmentally to a 2-year-old human. Administration of MPSS resulted in reduced structural damage (corpus callosum, cortex, hippocampus, striatum), gliosis and reactive microglia and partial restoration of the oligodendrocyte population. Furthermore, significant behavioural recovery was observed. In conclusion, we demonstrated that administration of MPSS during the tertiary phase of perinatal stroke results in attenuation of the chronic inflammatory response, leading to pathophysiological and functional recovery. This work validates the high clinical impact of MPSS to treat neonatal conditions linked to chronic inflammation.
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Affiliation(s)
- Svetlana Altamentova
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Prakasham Rumajogee
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - James Hong
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Stephanie R Beldick
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Sei Joon Park
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Albert Yee
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Michael G Fehlings
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada. .,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada. .,Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada. .,Division of Neurosurgery, Toronto Western Hospital, University Health Network, 399 Bathurst St. Suite 4WW-449, Toronto, Ontario, M5T 2S8, Canada.
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22
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Papanikolaou M, Butt AM, Lewis A. A critical role for the inward rectifying potassium channel Kir7.1 in oligodendrocytes of the mouse optic nerve. Brain Struct Funct 2020; 225:925-934. [PMID: 32086565 PMCID: PMC7166203 DOI: 10.1007/s00429-020-02043-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 02/06/2020] [Indexed: 01/27/2023]
Abstract
Inward rectifying potassium channels (Kir) are a large family of ion channels that play key roles in ion homeostasis in oligodendrocytes, the myelinating cells of the central nervous system (CNS). Prominent expression of Kir4.1 has been indicated in oligodendrocytes, but the extent of expression of other Kir subtypes is unclear. Here, we used qRT-PCR to determine expression of Kir channel transcripts in the mouse optic nerve, a white matter tract comprising myelinated axons and the glia that support them. A novel finding was the high relative expression of Kir7.1, comparable to that of Kir4.1, the main glial Kir channel. Significantly, Kir7.1 immunofluorescence labelling in optic nerve sections and in isolated cells was localised to oligodendrocyte somata. Kir7.1 are known as a K+ transporting channels and, using patch clamp electrophysiology and the Kir7.1 blocker VU590, we demonstrated Kir7.1 channels carry a significant proportion of the whole cell potassium conductance in oligodendrocytes isolated from mouse optic nerves. Notably, oligodendrocytes are highly susceptible to ischemia/hypoxia and this is due at least in part to disruption of ion homeostasis. A key finding of this study is that blockade of Kir7.1 with VU590 compromised oligodendrocyte cell integrity and compounds oligodendroglial loss in ischemia/hypoxia in the oxygen-glucose deprivation (OGD) model in isolated intact optic nerves. These data reveal Kir7.1 channels are molecularly and functionally expressed in oligodendrocytes and play an important role in determining oligodendrocyte survival and myelin integrity.
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Affiliation(s)
- Maria Papanikolaou
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - Arthur M Butt
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK.
| | - Anthony Lewis
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
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23
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White Matter and Neuroprotection in Alzheimer's Dementia. Molecules 2020; 25:molecules25030503. [PMID: 31979414 PMCID: PMC7038211 DOI: 10.3390/molecules25030503] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/12/2022] Open
Abstract
Myelin is the main component of the white matter of the central nervous system (CNS), allowing the proper electrical function of the neurons by ensheathing and insulating the axons. The extensive use of magnetic resonance imaging has highlighted the white matter alterations in Alzheimer’s dementia (AD) and other neurodegenerative diseases, alterations which are early, extended, and regionally selective. Given that the white matter turnover is considerable in the adulthood, and that myelin repair is currently recognized as being the only true reparative capability of the mature CNS, oligodendrocyte precursor cells (OPCs), the cells that differentiate in oligodendrocyte, responsible for myelin formation and repair, are regarded as a potential target for neuroprotection. In this review, several aspects of the OPC biology are reviewed. The histology and functional role of OPCs in the neurovascular-neuroglial unit as described in preclinical and clinical studies on AD is discussed, such as the OPC vulnerability to hypoxia-ischemia, neuroinflammation, and amyloid deposition. Finally, the position of OPCs in drug discovery strategies for dementia is discussed.
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24
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Yu Y, Luo X, Li C, Ding F, Wang M, Xie M, Yu Z, Ransom BR, Wang W. Microglial Hv1 proton channels promote white matter injuries after chronic hypoperfusion in mice. J Neurochem 2019; 152:350-367. [PMID: 31769505 DOI: 10.1111/jnc.14925] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 11/16/2019] [Accepted: 11/19/2019] [Indexed: 12/30/2022]
Abstract
Microglia are critical in damage/repair processes during ischemic white matter injury (WMI). Voltage-gated proton channel (Hv1) is expressed in microglia and contributes to nicotinamide adenine dinucleotide phosphate oxidase complex-dependent production of reactive oxygen species (ROS). Recent findings have shown that Hv1 is involved in regulating luminal pH of M1-polarized microglial phagosomes and inhibits endocytosis in microglia. We previously reported that Hv1 facilitated production of ROS and pro-inflammatory cytokines in microglia and enhanced damage to oligodendrocyte progenitor cells from oxygen and glucose deprivation. To investigate the role of Hv1 in hypoperfusion-induced WMI, we employed mice that were genetically devoid of Hv1 (Hv1-/- ), as well as a model of subcortical vascular dementia via bilateral common carotid artery stenosis. Integrity of myelin was assessed using immunofluorescent staining and transmission electron microscopy, while cognitive impairment was assessed using an eight-arm radial maze test. Hv1 deficiency was found to attenuate bilateral common carotid artery stenosis-induced disruption of white matter integrity and impairment of working memory. Immunofluorescent staining and western blotting were used to assay changes in oligodendrocytes, OPCs, and microglial polarization. Compared with that in wild-type (WT) mice, Hv1-/- mice exhibited reduced ROS generation, decreased pro-inflammatory cytokines production, and an M2-dominant rather than M1-dominant microglial polarization. Furthermore, Hv1-/- mice exhibited enhanced OPC proliferation and differentiation into oligodendrocytes. Results of mouse-derived microglia-OPC co-cultures suggested that PI3K/Akt signaling was involved in Hv1-deficiency-induced M2-type microglial polarization and concomitant OPC differentiation. These results suggest that microglial Hv1 is a promising therapeutic target for reducing ischemic WMI and cognitive impairment.
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Affiliation(s)
- Ying Yu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiang Luo
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chunyu Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fengfei Ding
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Minghuan Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Minjie Xie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhiyuan Yu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bruce R Ransom
- Department of Neurology, University of Washington School of Medicine HMC, Seattle, WA, USA
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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25
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Bastian C, Day J, Politano S, Quinn J, Brunet S, Baltan S. Preserving Mitochondrial Structure and Motility Promotes Recovery of White Matter After Ischemia. Neuromolecular Med 2019; 21:484-492. [PMID: 31152363 PMCID: PMC6884671 DOI: 10.1007/s12017-019-08550-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 05/20/2019] [Indexed: 12/23/2022]
Abstract
Stroke significantly affects white matter in the brain by impairing axon function, which results in clinical deficits. Axonal mitochondria are highly dynamic and are transported via microtubules in the anterograde or retrograde direction, depending upon axonal energy demands. Recently, we reported that mitochondrial division inhibitor 1 (Mdivi-1) promotes axon function recovery by preventing mitochondrial fission only when applied during ischemia. Application of Mdivi-1 after injury failed to protect axon function. Interestingly, L-NIO, which is a NOS3 inhibitor, confers post-ischemic protection to axon function by attenuating mitochondrial fission and preserving mitochondrial motility via conserving levels of the microtubular adaptor protein Miro-2. We propose that preventing mitochondrial fission protects axon function during injury, but that restoration of mitochondrial motility is more important to promote axon function recovery after injury. Thus, Miro-2 may be a therapeutic molecular target for recovery following a stroke.
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Affiliation(s)
- Chinthasagar Bastian
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Jerica Day
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Stephen Politano
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - John Quinn
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Sylvain Brunet
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Selva Baltan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA.
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26
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Baldassarro VA, Marchesini A, Giardino L, Calzà L. Differential effects of glucose deprivation on the survival of fetal versus adult neural stem cells-derived oligodendrocyte precursor cells. Glia 2019; 68:898-917. [PMID: 31755592 DOI: 10.1002/glia.23750] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 12/27/2022]
Abstract
Impaired myelination is a key feature in neonatal hypoxia/ischemia (HI), the most common perinatal/neonatal cause of death and permanent disabilities, which is triggered by the establishment of an inflammatory and hypoxic environment during the most critical period of myelin development. This process is dependent on oligodendrocyte precursor cells (OPCs) and their capability to differentiate into mature oligodendrocytes. In this study, we investigated the vulnerability of fetal and adult OPCs derived from neural stem cells (NSCs) to inflammatory and HI insults. The resulting OPCs/astrocytes cultures were exposed to cytokines to mimic inflammation, or to oxygen-glucose deprivation (OGD) to mimic an HI condition. The differentiation of both fetal and adult OPCs is completely abolished following exposure to inflammatory cytokines, while only fetal-derived OPCs degenerate when exposed to OGD. We then investigated possible mechanisms involved in OGD-mediated toxicity: (a) T3-mediated maturation induction; (b) glutamate excitotoxicity; (c) glucose metabolism. We found that while no substantial differences were observed in T3 intracellular content regulation and glutamate-mediated toxicity, glucose deprivation lead to selective OPC cell death and impaired differentiation in fetal cultures only. These results indicate that the biological response of OPCs to inflammation and demyelination is different in fetal and adult cells, and that the glucose metabolism perturbation in fetal central nervous system (CNS) may significantly contribute to neonatal pathologies. An understanding of the underlying molecular mechanism will contribute greatly to differentiating myelination enhancing and neuroprotective therapies for neonatal and adult CNS white matter lesions.
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Affiliation(s)
- Vito Antonio Baldassarro
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | | | - Luciana Giardino
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy.,Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Laura Calzà
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy
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27
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Gerkau NJ, Rakers C, Durry S, Petzold GC, Rose CR. Reverse NCX Attenuates Cellular Sodium Loading in Metabolically Compromised Cortex. Cereb Cortex 2019; 28:4264-4280. [PMID: 29136153 DOI: 10.1093/cercor/bhx280] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 10/04/2017] [Indexed: 01/05/2023] Open
Abstract
In core regions of ischemic stroke, disruption of blood flow causes breakdown of ionic gradients and, ultimately, calcium overload and cell death. In the surrounding penumbra, cells may recover upon reperfusion, but recovery is hampered by additional metabolic demands imposed by peri-infarct depolarizations (PIDs). There is evidence that sodium influx drives PIDs, but no data exist on PID-related sodium accumulations in vivo. Here, we found that PIDs in mouse neocortex are associated with propagating sodium elevations in neurons and astrocytes. Similar transient sodium elevations were induced in acute tissue slices by brief chemical ischemia. Blocking NMDA-receptors dampened sodium and accompanying calcium loads of neurons in tissue slices, while inhibiting glutamate transport diminished sodium influx into astrocytes, but amplified neuronal sodium loads. In both cell types, inhibition of sodium/calcium exchange (NCX) increased sodium transients. Blocking NCX also significantly reduced calcium transients, a result confirmed in vivo. Our study provides the first quantitative data on sodium elevations in peri-infarct regions in vivo. They suggest that sodium influx drives reversal of NCX, triggering a massive secondary calcium elevation while promoting export of sodium. Reported neuroprotective effects of NCX activity in stroke models might thus be related to its dampening of ischemia-induced sodium loading.
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Affiliation(s)
- Niklas J Gerkau
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, Duesseldorf, Germany
| | - Cordula Rakers
- German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, Bonn, Germany
| | - Simone Durry
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, Duesseldorf, Germany
| | - Gabor C Petzold
- German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, Bonn, Germany.,Department of Neurology, University Hospital Bonn, Sigmund-Freud-Str. 25, Bonn, Germany
| | - Christine R Rose
- Institute of Neurobiology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, Duesseldorf, Germany
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28
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Emmons-Bell M, Durant F, Tung A, Pietak A, Miller K, Kane A, Martyniuk CJ, Davidian D, Morokuma J, Levin M. Regenerative Adaptation to Electrochemical Perturbation in Planaria: A Molecular Analysis of Physiological Plasticity. iScience 2019; 22:147-165. [PMID: 31765995 PMCID: PMC6881696 DOI: 10.1016/j.isci.2019.11.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 10/01/2019] [Accepted: 11/05/2019] [Indexed: 12/29/2022] Open
Abstract
Anatomical homeostasis results from dynamic interactions between gene expression, physiology, and the external environment. Owing to its complexity, this cellular and organism-level phenotypic plasticity is still poorly understood. We establish planarian regeneration as a model for acquired tolerance to environments that alter endogenous physiology. Exposure to barium chloride (BaCl2) results in a rapid degeneration of anterior tissue in Dugesia japonica. Remarkably, continued exposure to fresh solution of BaCl2 results in regeneration of heads that are insensitive to BaCl2. RNA-seq revealed transcriptional changes in BaCl2-adapted heads that suggests a model of adaptation to excitotoxicity. Loss-of-function experiments confirmed several predictions: blockage of chloride and calcium channels allowed heads to survive initial BaCl2 exposure, inducing adaptation without prior exposure, whereas blockade of TRPM channels reversed adaptation. Such highly adaptive plasticity may represent an attractive target for biomedical strategies in a wide range of applications beyond its immediate relevance to excitotoxicity preconditioning. Exposure to BaCl2 causes the heads of Dugesia japonica to degenerate Prolonged exposure to BaCl2 results in regeneration of a BaCl2-insensitive head Ion channel expression is altered in the head to compensate for excitotoxic stress TRPMa is upregulated in BaCl2-treated animals; blocking TRPM prevents adaptation
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Affiliation(s)
- Maya Emmons-Bell
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Fallon Durant
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Angela Tung
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Alexis Pietak
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA
| | - Kelsie Miller
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA
| | - Anna Kane
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA
| | - Christopher J Martyniuk
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, USA
| | - Devon Davidian
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Junji Morokuma
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Michael Levin
- Allen Discovery Center at Tufts University, Medford, MA 02155, USA; Department of Biology, Tufts University, Medford, MA 02155, USA.
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29
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Ceprian M, Fulton D. Glial Cell AMPA Receptors in Nervous System Health, Injury and Disease. Int J Mol Sci 2019; 20:E2450. [PMID: 31108947 PMCID: PMC6566241 DOI: 10.3390/ijms20102450] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/11/2019] [Accepted: 04/22/2019] [Indexed: 12/16/2022] Open
Abstract
Glia form a central component of the nervous system whose varied activities sustain an environment that is optimised for healthy development and neuronal function. Alpha-amino-3-hydroxy-5-methyl-4-isoxazole (AMPA)-type glutamate receptors (AMPAR) are a central mediator of glutamatergic excitatory synaptic transmission, yet they are also expressed in a wide range of glial cells where they influence a variety of important cellular functions. AMPAR enable glial cells to sense the activity of neighbouring axons and synapses, and as such many aspects of glial cell development and function are influenced by the activity of neural circuits. However, these AMPAR also render glia sensitive to elevations of the extracellular concentration of glutamate, which are associated with a broad range of pathological conditions. Excessive activation of AMPAR under these conditions may induce excitotoxic injury in glial cells, and trigger pathophysiological responses threatening other neural cells and amplifying ongoing disease processes. The aim of this review is to gather information on AMPAR function from across the broad diversity of glial cells, identify their contribution to pathophysiological processes, and highlight new areas of research whose progress may increase our understanding of nervous system dysfunction and disease.
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Affiliation(s)
- Maria Ceprian
- Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040 Madrid, Spain.
- Departamento de Bioquímica y Biología Molecular, CIBERNED, IRICYS. Facultad de Medicina, Universidad Complutense de Madrid, 28040 Madrid, Spain.
| | - Daniel Fulton
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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30
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Heterogeneity of Activity-Induced Sodium Transients between Astrocytes of the Mouse Hippocampus and Neocortex: Mechanisms and Consequences. J Neurosci 2019; 39:2620-2634. [PMID: 30737311 DOI: 10.1523/jneurosci.2029-18.2019] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/07/2019] [Accepted: 01/23/2019] [Indexed: 01/09/2023] Open
Abstract
Activity-related sodium transients induced by glutamate uptake represent a special form of astrocyte excitability. Astrocytes of the neocortex, as opposed to the hippocampus proper, also express ionotropic glutamate receptors, which might provide additional sodium influx. We compared glutamate-related sodium transients in astrocytes and neurons in slices of the neocortex and hippocampus of juvenile mice of both sexes, using widefield and multiphoton imaging. Stimulation of glutamatergic afferents or glutamate application induced sodium transients that were twice as large in neocortical as in hippocampal astrocytes, despite similar neuronal responses. Astrocyte sodium transients were reduced by ∼50% upon blocking NMDA receptors in the neocortex, but not hippocampus. Neocortical, but not hippocampal, astrocytes exhibited marked sodium increases in response to NMDA. These key differences in sodium signaling were also observed in neonates and in adults. NMDA application evoked local calcium transients in processes of neocortical astrocytes, which were dampened upon blocking sodium/calcium exchange (NCX) with KB-R7943 or SEA0400. Mathematical computation based on our data predict that NMDA-induced sodium increases drive the NCX into reverse mode, resulting in calcium influx. Together, our study reveals a considerable regional heterogeneity in astrocyte sodium transients, which persists throughout postnatal development. Neocortical astrocytes respond with much larger sodium elevations to glutamatergic activity than hippocampal astrocytes. Moreover, neocortical astrocytes experience NMDA-receptor-mediated sodium influx, which hippocampal astrocytes lack, and which drives calcium import through reverse NCX. This pathway thereby links sodium to calcium signaling and represents a new mechanism for the generation of local calcium influx in neocortical astrocytes.SIGNIFICANCE STATEMENT Astrocyte calcium signals play a central role in neuron-glia interaction. Moreover, activity-related sodium transients may represent a new form of astrocyte excitability. Here we show that activation of NMDA receptors results in prominent sodium transients in neocortical, but not hippocampal, astrocytes in the mouse brain. NMDA receptor activation is accompanied by local calcium signaling in processes of neocortical astrocytes, which is augmented by sodium-driven reversal of the sodium/calcium exchanger. Our data demonstrate a significant regional heterogeneity in the magnitude and mechanisms of astrocyte sodium transients. They also suggest a close interrelation between NMDA-receptor-mediated sodium influx and calcium signaling through the reversal of sodium/calcium exchanger, thereby establishing a new pathway for the generation of local calcium signaling in astrocyte processes.
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Peng J, Pang J, Huang L, Enkhjargal B, Zhang T, Mo J, Wu P, Xu W, Zuo Y, Peng J, Zuo G, Chen L, Tang J, Zhang JH, Jiang Y. LRP1 activation attenuates white matter injury by modulating microglial polarization through Shc1/PI3K/Akt pathway after subarachnoid hemorrhage in rats. Redox Biol 2019; 21:101121. [PMID: 30703614 PMCID: PMC6351270 DOI: 10.1016/j.redox.2019.101121] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/18/2019] [Accepted: 01/22/2019] [Indexed: 12/21/2022] Open
Abstract
White matter injury (WMI) is associated with motor deficits and cognitive dysfunctions in subarachnoid hemorrhage (SAH) patients. Therapeutic strategy targeting WMI would likely improve the neurological outcomes after SAH. Low-density lipoprotein receptor-related protein-1 (LRP1), a scavenger receptor of apolipoprotein E (apoE), is able to modulate microglia polarization towards anti-inflammatory M2 phenotypes during inflammatory and oxidative insult. In the present study, we investigated the effects of LRP1 activation on WMI and underlying mechanisms of M2 microglial polarization in a rat model of SAH. Two hundred and seventeen male Sprague Dawley rats (weight 280-330 g) were used. SAH was induced by endovascular perforation. LPR1 ligand, apoE-mimic peptide COG1410 was administered intraperitoneally. Microglial depletion kit liposomal clodronate (CLP), LPR1 siRNA or PI3K inhibitor were administered intracerebroventricularly. Post-SAH assessments included neurobehavioral tests, brain water content, immunohistochemistry, Golgi staining, western blot and co-immunoprecipitation. SAH induced WMI shown as the accumulation of amyloid precursor protein and neurofilament heavy polypeptide as well as myelin loss. Microglial depletion by CLP significantly suppressed WMI after SAH. COG1410 reduced brain water content, increased the anti-inflammatory M2 microglial phenotypes, attenuated WMI and improved neurological function after SAH. LRP1 was bound with endogenous apoE and intracellular adaptor protein Shc1. The benefits of COG1410 were reversed by LPR1 siRNA or PI3K inhibitor. LRP1 activation attenuated WMI and improved neurological function by modulating M2 microglial polarization at least in part through Shc1/PI3K/Akt signaling in a rat model of SAH. The apoE-mimic peptide COG1410 may serve as a promising treatment in the management of SAH patients.
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Affiliation(s)
- Jianhua Peng
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China; Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Jinwei Pang
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China; Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Lei Huang
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Budbazar Enkhjargal
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Tongyu Zhang
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Jun Mo
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Pei Wu
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Weilin Xu
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Yuchun Zuo
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Jun Peng
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Gang Zuo
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - Ligang Chen
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Jiping Tang
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA
| | - John H Zhang
- Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92350, USA; Department of Anesthesiology, Loma Linda University, Loma Linda, CA 92350, USA; Department of Neurosurgery, Loma Linda University, Loma Linda, CA 92350, USA.
| | - Yong Jiang
- Department of Neurosurgery, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China; Neurosurgery Clinical Medical Research Center of Sichuan Province, Luzhou, Sichuan 646000, China; Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Luzhou, Sichuan 646000, China.
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Butt AM, De La Rocha IC, Rivera A. Oligodendroglial Cells in Alzheimer's Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1175:325-333. [PMID: 31583593 DOI: 10.1007/978-981-13-9913-8_12] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Oligodendrocytes form the myelin that ensheaths CNS axons, which is essential for rapid neuronal signalling and underpins the massive computing power of the human brain. Oligodendrocytes and myelin also provide metabolic and trophic support for axons and their disruption results in axonal demise and neurodegeneration, which are key features of Alzheimer's disease (AD). Notably, the brain has a remarkable capacity for regenerating oligodendrocytes, which is the function of adult oligodendrocyte progenitor cells (OPCs) or NG2-glia. White matter loss is often among the earliest brain changes in AD, preceding the tangles and plaques that characterize neuronal deficits. The underlying causes of myelin loss include oxidative stress, neuroinflammation and excitotoxicity, associated with accumulation of Aβ and tau hyperphosphorylation, pathological hallmarks of AD. Moreover, there is evidence that NG2-glia are disrupted in AD, which may be associated with disruption of synaptic signalling. This has led to the hypothesis that a vicious cycle of myelin loss and failure of regeneration from NG2-glia plays a key role in AD. Therapies that target NG2-glia are likely to have positive effects on myelination and neuroprotection in AD.
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Affiliation(s)
- Arthur M Butt
- School of Pharmacy and Biomedical Science, University of Portsmouth, St. Michael's Building, White Sawn Road, Portsmouth, PO1 2DT, UK.
| | - Irene Chacon De La Rocha
- School of Pharmacy and Biomedical Science, University of Portsmouth, St. Michael's Building, White Sawn Road, Portsmouth, PO1 2DT, UK
| | - Andrea Rivera
- School of Pharmacy and Biomedical Science, University of Portsmouth, St. Michael's Building, White Sawn Road, Portsmouth, PO1 2DT, UK
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Spampinato SF, Copani A, Nicoletti F, Sortino MA, Caraci F. Metabotropic Glutamate Receptors in Glial Cells: A New Potential Target for Neuroprotection? Front Mol Neurosci 2018; 11:414. [PMID: 30483053 PMCID: PMC6243036 DOI: 10.3389/fnmol.2018.00414] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 10/25/2018] [Indexed: 12/14/2022] Open
Abstract
Neurodegenerative disorders are characterized by excitotoxicity and neuroinflammation that finally lead to slow neuronal degeneration and death. Although neurons are the principal target, glial cells are important players as they contribute by either exacerbating or dampening the events that lead to neuroinflammation and neuronal damage. A dysfunction of the glutamatergic system is a common event in the pathophysiology of these diseases. Metabotropic glutamate (mGlu) receptors belong to a large family of G protein-coupled receptors largely expressed in neurons as well as in glial cells. They often appear overexpressed in areas involved in neurodegeneration, where they can modulate glutamatergic transmission. Of note, mGlu receptor upregulation may involve microglia or, even more frequently, astrocytes, where their activation causes release of factors potentially able to influence neuronal death. The expression of mGlu receptors has been also reported on oligodendrocytes, a glial cell type specifically involved in the development of multiple sclerosis. Here we will provide a general overview on the possible involvement of mGlu receptors expressed on glial cells in the pathogenesis of different neurodegenerative disorders and the potential use of subtype-selective mGlu receptor ligands as candidate drugs for the treatment of neurodegenerative disorders. Negative allosteric modulators (NAM) of mGlu5 receptors might represent a relevant pharmacological tool to develop new neuroprotective strategies in these diseases. Recent evidence suggests that targeting astrocytes and microglia with positive allosteric modulators (PAM) of mGlu3 receptor or oligodendrocytes with mGlu4 PAMS might represent novel pharmacological approaches for the treatment of neurodegenerative disorders.
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Affiliation(s)
| | - Agata Copani
- Department of Drug Sciences, University of Catania, Catania, Italy.,Institute of Biostructure and Bioimaging, National Research Council, Catania, Italy
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,Neuromed, Istituto di Ricovero e Cura a Carattere Scientifico, Pozzilli, Italy
| | - Maria Angela Sortino
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Filippo Caraci
- Department of Drug Sciences, University of Catania, Catania, Italy.,Oasi Research Institute, Istituto di Ricovero e Cura a Carattere Scientifico, Troina, Italy
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He T, Zuo Y, Ai-Zakwani K, Luo J, Zhu H, Yan XX, Liu F. Subarachnoid hemorrhage enhances the expression of TDP-43 in the brain of experimental rats and human subjects. Exp Ther Med 2018; 16:3363-3368. [PMID: 30233682 PMCID: PMC6143865 DOI: 10.3892/etm.2018.6636] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 07/13/2018] [Indexed: 12/12/2022] Open
Abstract
The transactive response DNA-binding protein of 43 (TDP-43) may be involved in neurodegenerative disease and in the response to brain injury; however, alterations in the expression of TDP-43 following subarachnoid hemorrhage (SAH) require further investigation. The present study reported a notable elevation in the expression of TDP-43 within the cerebrospinal fluid (CSF) of patients with aneurysmal SAH and increased brain expression of TDP-43 in a rat model of SAH. The TDP-43 protein and a derivative migrated at 43 and 24 kDa, respectively, as observed via the immunoblotting of concentrated CSF samples obtained from patients with SAH; no signal was detected in the CSF from healthy controls. SAH in rats was induced by intravascular suture puncture. The expression levels of TDP-43 in rat cortical lysates following SAH were increased at 0.5 h, peaked at 48 h and remained significantly elevated at 72 h post-injury, compared with sham controls. TDP-43 immunolabeling indication localization within neurons, astrocytes and microglia in the experimental rats. Collectively, the findings of the present study indicated the early involvement of TDP-43 in the brain in response to SAH, and that expression levels of TDP-43 in the CSF may serve as a prognostic biomarker among patients with this condition.
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Affiliation(s)
- Tibiao He
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Yuchun Zuo
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Kauthar Ai-Zakwani
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Jing Luo
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Haixia Zhu
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, School of Basic Medical Science, Central South University, Changsha, Hunan 410013, P.R. China
| | - Fei Liu
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, P.R. China
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35
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Soluble epoxide hydrolase inhibition alleviated cognitive impairments via NRG1/ErbB4 signaling after chronic cerebral hypoperfusion induced by bilateral carotid artery stenosis in mice. Brain Res 2018; 1699:89-99. [PMID: 30343686 DOI: 10.1016/j.brainres.2018.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 07/01/2018] [Accepted: 07/02/2018] [Indexed: 12/19/2022]
Abstract
Cerebral ischemic stroke is associated with a high rate of incidence, prevalence and mortality globally. Carotid artery stenosis, which is mainly caused by atherosclerosis plaque, results in chronic cerebral hypoperfusion and predominantly increases the risk of ischemic stroke. In the present study, we used bilateral common carotid artery stenosis (BCAS) model by placing microcoils of 0.18 mm diameter encompassing both common carotid arteries respectively, to mimic the pathogenesis of carotid artery atherosclerosis and intensively explore the pathology. We found that BCAS injury for 1 month impaired spatial cognitive functions significantly, and inhibited synaptic plasticity, including hippocampal long-term potentiation (LTP) inhibition, dendritic spine density reduction and synaptic associative proteins disorder. BCAS-induced cerebral hypoperfused mice treated with 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl]urea (TPPU), a potent soluble epoxide hydrolase (sEH) inhibitor, exhibited amelioration of cognitive dysfunction and improved synaptic plasticity. The neural protective effects of TPPU on BCAS-induced cerebral hypoperfusion might due to activation of neuregulin-1 (NRG1)/ErbB4 signaling, and triggered PI3K-Akt pathways subsequently. Our results suggested that sEH inhibition could exert multi-target protective effects and alleviate spatial cognitive dysfunctions after chronic cerebral hypoperfusion in mice.
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36
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Camara-Lemarroy CR, Metz L, Smith EE, Dunn JF, Yong VW. Expanding the Potential Therapeutic Options for Remote Ischemic Preconditioning: Use in Multiple Sclerosis. Front Neurol 2018; 9:475. [PMID: 29971043 PMCID: PMC6018107 DOI: 10.3389/fneur.2018.00475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/01/2018] [Indexed: 12/11/2022] Open
Affiliation(s)
- Carlos R Camara-Lemarroy
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,UANL School of Medicine and University Hospital, Monterrey, Mexico
| | - Luanne Metz
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Eric E Smith
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jeff F Dunn
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - V Wee Yong
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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37
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Begum G, Otsu M, Ahmed U, Ahmed Z, Stevens A, Fulton D. NF-Y-dependent regulation of glutamate receptor 4 expression and cell survival in cells of the oligodendrocyte lineage. Glia 2018; 66:1896-1914. [PMID: 29704264 PMCID: PMC6220837 DOI: 10.1002/glia.23446] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 03/14/2018] [Accepted: 04/11/2018] [Indexed: 12/15/2022]
Abstract
Glutamate receptor subunit 4 (GluA4) is highly expressed by neural cells sensitive to excitotoxicity, and is the predominant subunit expressed by oligodendrocyte precursor cells (OPC) during a key period of vulnerability to hypoxic‐ischemic injury. Therefore, transcriptional networks downstream of excitotoxic GluA4 activation represent a promising area for therapeutic intervention. In this work, we identify the CCAAT binding transcription factor NF‐Yb as a novel transcriptional regulator of Gria4 (GluA4 gene), and a controller of excitotoxic death in the oligodendroglial lineage. We describe a novel regulatory region within Gria4 containing CCAAT sequences whose binding by NF‐Yb is regulated by excitotoxicity. Excitotoxicity‐induced alterations in NF‐Yb binding are associated with changes in Gria4 transcription, while knockdown of NF‐Yb alters the transcription of reporter constructs containing this regulatory region. Data from immortalized and primary OPC reveal that RNAi and pharmacological disruption of NF‐Yb alter Gria4 transcription, with the latter inducing apoptosis and influencing a set of apoptotic genes similarly regulated during excitotoxicity. These data provide the first definition of a trans‐acting mechanism regulating Gria4, and identify the NF‐Y network as a potential source of pharmacological targets for promoting OPC survival.
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Affiliation(s)
- Ghazala Begum
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Masahiro Otsu
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Usman Ahmed
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Zubair Ahmed
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Adam Stevens
- Division of Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester, Manchester Academic Health Sciences Centre, Manchester M13 9PL, United Kingdom
| | - Daniel Fulton
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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Mattugini N, Merl-Pham J, Petrozziello E, Schindler L, Bernhagen J, Hauck SM, Götz M. Influence of white matter injury on gray matter reactive gliosis upon stab wound in the adult murine cerebral cortex. Glia 2018; 66:1644-1662. [PMID: 29573353 DOI: 10.1002/glia.23329] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 02/13/2018] [Accepted: 03/02/2018] [Indexed: 01/01/2023]
Abstract
Traumatic brain injury frequently affects the cerebral cortex, yet little is known about the differential effects that occur if only the gray matter (GM) is damaged or if the injury also involves the white matter (WM). To tackle this important question and directly compare similarities and differences in reactive gliosis, we performed stab wound injury affecting GM and WM (GM+) and one restricted to the GM (GM-) in the adult murine cerebral cortex. First, we examined glial reactivity in the regions affected (WM and GM) and determined the influence of WM injury on reactive gliosis in the GM comparing the same area in the two injury paradigms. In the GM+ injury microglia proliferation is increased in the WM compared with GM, while proliferating astrocytes are more abundant in the GM than in the WM. Interestingly, WM lesion exerted a strong influence on the proliferation of the GM glial cells that was most pronounced at early stages, 3 days post lesion. While astrocyte proliferation was increased, NG2 glia proliferation was decreased in the GM+ compared with GM- lesion condition. Importantly, these differences were not observed when a lesion of the same size affected only the GM. Unbiased proteomic analyses further corroborate our findings in support of a profound difference in GM reactivity when WM is also injured and revealed MIF as a key regulator of NG2 glia proliferation.
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Affiliation(s)
- Nicola Mattugini
- Physiological Genomics, Biomedical center (BMC), Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Institute of Stem Cell Research, Helmholtz Center Munich, Biomedical Center (BMC), Department of Physiological Genomics, Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Graduate School of Systemic Neurosciences Ludwig-Maximilians University (LMU), Großhaderner Str. 2, Planegg/Martinsried, 82152, Germany
| | - Juliane Merl-Pham
- Research Unit Protein Science, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg, 85764, Germany
| | - Elisabetta Petrozziello
- Institute for Immunology, Biomedical Center (BMC), Ludwig-Maximilians-University (LMU), Großhadernerstr. 9, Planegg/Martinsried, 82152, Germany
| | - Lisa Schindler
- Vascular Biology, Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Munich, Munich, 81377, Germany
| | - Jürgen Bernhagen
- Vascular Biology, Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Munich, Munich, 81377, Germany.,SyNergy Excellence Cluster, Munich, 81377, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg, 85764, Germany
| | - Magdalena Götz
- Physiological Genomics, Biomedical center (BMC), Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Institute of Stem Cell Research, Helmholtz Center Munich, Biomedical Center (BMC), Department of Physiological Genomics, Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,SyNergy Excellence Cluster, Munich, 81377, Germany
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Doyle S, Hansen DB, Vella J, Bond P, Harper G, Zammit C, Valentino M, Fern R. Vesicular glutamate release from central axons contributes to myelin damage. Nat Commun 2018. [PMID: 29531223 PMCID: PMC5847599 DOI: 10.1038/s41467-018-03427-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The axon myelin sheath is prone to injury associated with N-methyl-d-aspartate (NMDA)-type glutamate receptor activation but the source of glutamate in this context is unknown. Myelin damage results in permanent action potential loss and severe functional deficit in the white matter of the CNS, for example in ischemic stroke. Here, we show that in rats and mice, ischemic conditions trigger activation of myelinic NMDA receptors incorporating GluN2C/D subunits following release of axonal vesicular glutamate into the peri-axonal space under the myelin sheath. Glial sources of glutamate such as reverse transport did not contribute significantly to this phenomenon. We demonstrate selective myelin uptake and retention of a GluN2C/D NMDA receptor negative allosteric modulator that shields myelin from ischemic injury. The findings potentially support a rational approach toward a low-impact prophylactic therapy to protect patients at risk of stroke and other forms of excitotoxic injury. Neuronal activity can lead to vesicular release of glutamate. Here the authors demonstrate that vesicular release of glutamate occurs in axons during ischemic conditions, and that an allosteric modulator of GluN2C/D is protective in models of ischemic injury.
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Affiliation(s)
- Sean Doyle
- University of Plymouth, Plymouth, PL6 8BY, UK
| | | | | | - Peter Bond
- University of Plymouth, Plymouth, PL6 8BY, UK
| | | | | | | | - Robert Fern
- University of Plymouth, Plymouth, PL6 8BY, UK.
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40
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Jackson J, Bianco G, Rosa AO, Cowan K, Bond P, Anichtchik O, Fern R. White matter tauopathy: Transient functional loss and novel myelin remodeling. Glia 2018; 66:813-827. [PMID: 29315804 DOI: 10.1002/glia.23286] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 12/08/2017] [Accepted: 12/11/2017] [Indexed: 01/03/2023]
Abstract
Early white matter (WM) changes are common in dementia and may contribute to functional decline. We here examine this phenomenon in an induced dementia model for the first time. We report a novel and selective form of myelin injury as the first manifestation of tauopathy in the adult central nervous system. Myelin pathology rapidly followed the induction of a P301 tau mutation associated with fronto-temporal dementia in humans (rTG4510 line). Damage involved focal disruption of the ad-axonal myelin lamella and internal oligodendrocyte tongue process, followed by myelin remodeling with features of re-myelination that included myelin thinning and internodal shortening. The evolution of the re-myelinated phenotype was complete in the molecular layer of the dentate gyrus after 1 month and in the optic nerve (ON) after 9 months of transgene induction and proceeded in the absence of actual demyelination, reactive glial changes or inflammatory response. The initial rapid myelin pathology was associated with loss of WM function and performance decline in a novel recognition test and both these effects largely reversed during the myelin re-modeling phase. The initial phase of myelin injury was accompanied by disruption of the vesicle population present in the axoplasm of hippocampal and ON axons. Axoplasmic vesicle release is significant for the regulation of myelin plasticity and disruption of this pathway may underlie the myelin damage and remodeling evoked by tauopathy. WM dysfunction early in tauopathy will disorder neural circuits, the current findings suggest this event may make a significant contribution to early clinical deficit in dementia.
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Affiliation(s)
| | | | - Angelo O Rosa
- Plymouth Electron Microscopy Centre, University of Plymouth, Plymouth, United Kingdom
| | - Katrina Cowan
- Peninsula School of Medicine and Dentistry, University of Plymouth, PUPSMD, Plymouth, United Kingdom
| | - Peter Bond
- Plymouth Electron Microscopy Centre, University of Plymouth, Plymouth, United Kingdom
| | - Oleg Anichtchik
- Peninsula School of Medicine and Dentistry, University of Plymouth, PUPSMD, Plymouth, United Kingdom
| | - Robert Fern
- Peninsula School of Medicine and Dentistry, University of Plymouth, PUPSMD, Plymouth, United Kingdom
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41
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Teske N, Liessem A, Fischbach F, Clarner T, Beyer C, Wruck C, Fragoulis A, Tauber SC, Victor M, Kipp M. Chemical hypoxia-induced integrated stress response activation in oligodendrocytes is mediated by the transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2). J Neurochem 2018; 144:285-301. [PMID: 29210072 DOI: 10.1111/jnc.14270] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 11/18/2017] [Accepted: 11/20/2017] [Indexed: 01/08/2023]
Abstract
The extent of remyelination in multiple sclerosis lesions is often incomplete. Injury to oligodendrocyte progenitor cells can be a contributing factor for such incomplete remyelination. The precise mechanisms underlying insufficient repair remain to be defined, but oxidative stress appears to be involved. Here, we used immortalized oligodendrocyte cell lines as model systems to investigate a causal relation of oxidative stress and endoplasmic reticulum stress signaling cascades. OLN93 and OliNeu cells were subjected to chemical hypoxia by blocking the respiratory chain at various levels. Mitochondrial membrane potential and oxidative stress levels were quantified by flow cytometry. Endoplasmic reticulum stress was monitored by the expression induction of activating transcription factor 3 and 4 (Atf3, Atf4), DNA damage-inducible transcript 3 protein (Ddit3), and glucose-regulated protein 94. Lentiviral silencing of nuclear factor (erythroid-derived 2)-like 2 or kelch-like ECH-associated protein 1 was applied to study the relevance of NRF2 for endoplasmic reticulum stress responses. We demonstrate that inhibition of the respiratory chain induces oxidative stress in cultured oligodendrocytes which is paralleled by the expression induction of distinct mediators of the endoplasmic reticulum stress response, namely Atf3, Atf4, and Ddit3. Atf3 and Ddit3 expression induction is potentiated in kelch-like ECH-associated protein 1-deficient cells and absent in cells lacking the oxidative stress-related transcription factor NRF2. This study provides strong evidence that oxidative stress in oligodendrocytes activates endoplasmic reticulum stress response in a NRF2-dependent manner and, in consequence, might regulate oligodendrocyte degeneration in multiple sclerosis and other neurological disorders.
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Affiliation(s)
- Nico Teske
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Annette Liessem
- Institute of Neuroanatomy and JARA-BRAIN, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Felix Fischbach
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Tim Clarner
- Institute of Neuroanatomy and JARA-BRAIN, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Cordian Beyer
- Institute of Neuroanatomy and JARA-BRAIN, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Christoph Wruck
- Department of Anatomy and Cell Biology, RWTH Aachen University, Aachen, Germany
| | | | - Simone C Tauber
- Department of Neurology, RWTH University Hospital Aachen, Aachen, Germany
| | - Marion Victor
- Institute of Anatomy II, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Markus Kipp
- Department of Anatomy II, Ludwig-Maximilians-University of Munich, Munich, Germany
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42
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Bagi Z, Brandner DD, Le P, McNeal DW, Gong X, Dou H, Fulton DJ, Beller A, Ngyuen T, Larson EB, Montine TJ, Keene CD, Back SA. Vasodilator dysfunction and oligodendrocyte dysmaturation in aging white matter. Ann Neurol 2018; 83:142-152. [PMID: 29283444 PMCID: PMC5876126 DOI: 10.1002/ana.25129] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/24/2017] [Accepted: 12/26/2017] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Microvascular brain injury (mVBI) is a common pathological correlate of vascular contributions to cognitive impairment and dementia (VCID) that leads to white matter (WM) injury (WMI). VCID appears to arise from chronic recurrent white matter ischemia that triggers oxidative stress and an increase in total oligodendrocyte lineage cells. We hypothesized that mVBI involves vasodilator dysfunction of white matter penetrating arterioles and aberrant oligodendrocyte progenitor cell (OPC) responses to WMI. METHODS We analyzed cases of mVBI with low Alzheimer's disease neuropathological change in prefrontal cortex WM from rapid autopsies in a population-based cohort where VCID frequently occurs. Arteriolar vasodilator function was quantified by videomicroscopy. OPC maturation was quantified using lineage specific markers. RESULTS Acetylcholine-mediated arteriolar dilation in mVBI was significantly reduced in WM penetrators relative to pial arterioles. Astrogliosis-defined WMI was positively associated with increased OPCs and was negatively associated with decreased mature oligodendrocytes. INTERPRETATION Selectively impaired vasodilator function of WM penetrating arterioles in mVBI occurs in association with aberrant differentiation of OPCs in WMI, which supports that myelination disturbances in VCID are related to disrupted maturation of myelinating oligodendrocytes. Ann Neurol 2018;83:142-152.
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Affiliation(s)
- Zsolt Bagi
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912
- Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Dieter D. Brandner
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon 97239
| | - Phuong Le
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon 97239
| | - David W. McNeal
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon 97239
| | - Xi Gong
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon 97239
| | - Huijuan Dou
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - David J Fulton
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Allison Beller
- Department of Pathology, University of Washington, Seattle, Washington
| | - Thuan Ngyuen
- Department of Preventive Medicine, Oregon Health & Science University, Portland, Oregon 97239
| | | | - Thomas J. Montine
- Department of Pathology, University of Washington, Seattle, Washington
| | - C. Dirk Keene
- Department of Pathology, University of Washington, Seattle, Washington
| | - Stephen A. Back
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon 97239
- Department of Neurology, Oregon Health & Science University, Portland, Oregon 97239
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43
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Karam A, Trottier Y. Molecular Mechanisms and Therapeutic Strategies in Spinocerebellar Ataxia Type 7. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1049:197-218. [DOI: 10.1007/978-3-319-71779-1_9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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44
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Orem BC, Pelisch N, Williams J, Nally JM, Stirling DP. Intracellular calcium release through IP 3 R or RyR contributes to secondary axonal degeneration. Neurobiol Dis 2017; 106:235-243. [DOI: 10.1016/j.nbd.2017.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/28/2017] [Accepted: 07/10/2017] [Indexed: 11/27/2022] Open
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45
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Burnstock G. Purinergic Signalling: Therapeutic Developments. Front Pharmacol 2017; 8:661. [PMID: 28993732 PMCID: PMC5622197 DOI: 10.3389/fphar.2017.00661] [Citation(s) in RCA: 275] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/05/2017] [Indexed: 12/15/2022] Open
Abstract
Purinergic signalling, i.e., the role of nucleotides as extracellular signalling molecules, was proposed in 1972. However, this concept was not well accepted until the early 1990's when receptor subtypes for purines and pyrimidines were cloned and characterised, which includes four subtypes of the P1 (adenosine) receptor, seven subtypes of P2X ion channel receptors and 8 subtypes of the P2Y G protein-coupled receptor. Early studies were largely concerned with the physiology, pharmacology and biochemistry of purinergic signalling. More recently, the focus has been on the pathophysiology and therapeutic potential. There was early recognition of the use of P1 receptor agonists for the treatment of supraventricular tachycardia and A2A receptor antagonists are promising for the treatment of Parkinson's disease. Clopidogrel, a P2Y12 antagonist, is widely used for the treatment of thrombosis and stroke, blocking P2Y12 receptor-mediated platelet aggregation. Diquafosol, a long acting P2Y2 receptor agonist, is being used for the treatment of dry eye. P2X3 receptor antagonists have been developed that are orally bioavailable and stable in vivo and are currently in clinical trials for the treatment of chronic cough, bladder incontinence, visceral pain and hypertension. Antagonists to P2X7 receptors are being investigated for the treatment of inflammatory disorders, including neurodegenerative diseases. Other investigations are in progress for the use of purinergic agents for the treatment of osteoporosis, myocardial infarction, irritable bowel syndrome, epilepsy, atherosclerosis, depression, autism, diabetes, and cancer.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical SchoolLondon, United Kingdom
- Department of Pharmacology and Therapeutics, The University of Melbourne, MelbourneVIC, Australia
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46
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Shiow LR, Favrais G, Schirmer L, Schang AL, Cipriani S, Andres C, Wright JN, Nobuta H, Fleiss B, Gressens P, Rowitch DH. Reactive astrocyte COX2-PGE2 production inhibits oligodendrocyte maturation in neonatal white matter injury. Glia 2017; 65:2024-2037. [PMID: 28856805 DOI: 10.1002/glia.23212] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/12/2017] [Accepted: 08/08/2017] [Indexed: 12/19/2022]
Abstract
Inflammation is a major risk factor for neonatal white matter injury (NWMI), which is associated with later development of cerebral palsy. Although recent studies have demonstrated maturation arrest of oligodendrocyte progenitor cells (OPCs) in NWMI, the identity of inflammatory mediators with direct effects on OPCs has been unclear. Here, we investigated downstream effects of pro-inflammatory IL-1β to induce cyclooxygenase-2 (COX2) and prostaglandin E2 (PGE2) production in white matter. First, we assessed COX2 expression in human fetal brain and term neonatal brain affected by hypoxic-ischemic encephalopathy (HIE). In the developing human brain, COX2 was expressed in radial glia, microglia, and endothelial cells. In human term neonatal HIE cases with subcortical WMI, COX2 was strongly induced in reactive astrocytes with "A2" reactivity. Next, we show that OPCs express the EP1 receptor for PGE2, and PGE2 acts directly on OPCs to block maturation in vitro. Pharmacologic blockade with EP1-specific inhibitors (ONO-8711, SC-51089), or genetic deficiency of EP1 attenuated effects of PGE2. In an IL-1β-induced model of NWMI, astrocytes also exhibit "A2" reactivity and induce COX2. Furthermore, in vivo inhibition of COX2 with Nimesulide rescues hypomyelination and behavioral impairment. These findings suggest that neonatal white matter astrocytes can develop "A2" reactivity that contributes to OPC maturation arrest in NWMI through induction of COX2-PGE2 signaling, a pathway that can be targeted for neonatal neuroprotection.
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Affiliation(s)
- Lawrence R Shiow
- Department of Pediatrics and Division of Neonatology.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California
| | - Geraldine Favrais
- INSERM U930, Universite Francois Rabelais, Tours, France.,Neonatal intensive care unit, CHRU de Tours, Universite Francois Rabelais, Tours, France.,PROTECT, INSERM, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France
| | - Lucas Schirmer
- Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California.,Department of Neurology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Anne-Laure Schang
- PROTECT, INSERM, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,PremUP, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France
| | - Sara Cipriani
- PROTECT, INSERM, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,PremUP, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France
| | | | - Jaclyn N Wright
- Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California
| | - Hiroko Nobuta
- Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California
| | - Bobbi Fleiss
- PROTECT, INSERM, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,PremUP, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,Department of Perinatal Imaging and Health, Department of Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas Hospital, London, United Kingdom
| | - Pierre Gressens
- PROTECT, INSERM, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,PremUP, Universite Paris Diderot, Sorbonne Paris Cite, Paris, France.,Department of Perinatal Imaging and Health, Department of Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas Hospital, London, United Kingdom
| | - David H Rowitch
- Department of Pediatrics and Division of Neonatology.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California.,Department of Paediatrics, and Wellcome Trust-MRC Stem Cell Institute, Cambridge University, Cambridge, United Kingdom
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47
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Fontaine AK, Gibson EA, Caldwell JH, Weir RF. Optical Read-out of Neural Activity in Mammalian Peripheral Axons: Calcium Signaling at Nodes of Ranvier. Sci Rep 2017; 7:4744. [PMID: 28720792 PMCID: PMC5516017 DOI: 10.1038/s41598-017-03541-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/28/2017] [Indexed: 12/11/2022] Open
Abstract
Current neural interface technologies have serious limitations for advanced prosthetic and therapeutic applications due primarily to their lack of specificity in neural communication. An optogenetic approach has the potential to provide single cell/axon resolution in a minimally invasive manner by optical interrogation of light-sensitive reporters and actuators. Given the aim of reading neural activity in the peripheral nervous system, this work has investigated an activity-dependent signaling mechanism in the peripheral nerve. We demonstrate action potential evoked calcium signals in mammalian tibial nerve axons using an in vitro mouse model with a dextran-conjugated fluorescent calcium indicator. Spatial and temporal dynamics of the signal are presented, including characterization of frequency-modulated amplitude. Pharmacological experiments implicate T-type CaV channels and sodium-calcium exchanger (NCX) as predominant mechanisms of calcium influx. This work shows the potential of using calcium-associated optical signals for neural activity read-out in peripheral nerve axons.
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Affiliation(s)
- Arjun K Fontaine
- Department of Bioengineering, University of Colorado - Anschutz Medical Campus, Colorado, USA.
| | - Emily A Gibson
- Department of Bioengineering, University of Colorado - Anschutz Medical Campus, Colorado, USA
| | - John H Caldwell
- Department of Cell and Developmental Biology, University of Colorado - Anschutz Medical Campus, Colorado, USA
| | - Richard F Weir
- Department of Bioengineering, University of Colorado - Anschutz Medical Campus, Colorado, USA
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48
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Scheller A, Bai X, Kirchhoff F. The Role of the Oligodendrocyte Lineage in Acute Brain Trauma. Neurochem Res 2017; 42:2479-2489. [PMID: 28702713 DOI: 10.1007/s11064-017-2343-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/23/2017] [Accepted: 06/26/2017] [Indexed: 01/10/2023]
Abstract
An acute brain injury is commonly characterized by an extended cellular damage. The post-injury process of scar formation is largely determined by responses of various local glial cells and blood-derived immune cells. The role of astrocytes and microglia have been frequently reviewed in the traumatic sequelae. Here, we summarize the diverse contributions of oligodendrocytes (OLs) and their precursor cells (OPCs) in acute injuries. OLs at the lesion site are highly sensitive to a damaging insult, provoked by Ca2+ overload after hyperexcitation originating from increased levels of transmitters. At the lesion site, differentiating OPCs can replace injured oligodendrocytes to guarantee proper myelination that is instrumental for healthy brain function. In contrast to finally differentiated and non-dividing OLs, OPCs are the most proliferative cells of the brain and their proliferation rate even increases after injury. There exist even evidence that OPCs might also generate some type of astrocyte beside OLs. Thereby, OPCs can contribute to the generation and maintenance of the glial scar. In the future, detailed knowledge of the molecular cues that help to prevent injury-evoked glial cell death and that control differentiation and myelination of the oligodendroglial lineage will be pivotal in developing novel therapeutic approaches.
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Affiliation(s)
- Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421, Homburg, Germany
| | - Xianshu Bai
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421, Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, 66421, Homburg, Germany.
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49
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Fern R. The Leukocentric Theory of Neurological Disorder: A Manifesto. Neurochem Res 2017; 42:2666-2672. [DOI: 10.1007/s11064-017-2279-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/12/2017] [Accepted: 04/21/2017] [Indexed: 01/26/2023]
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50
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Butt AM, Vanzulli I, Papanikolaou M, De La Rocha IC, Hawkins VE. Metabotropic Glutamate Receptors Protect Oligodendrocytes from Acute Ischemia in the Mouse Optic Nerve. Neurochem Res 2017; 42:2468-2478. [PMID: 28365868 PMCID: PMC5603641 DOI: 10.1007/s11064-017-2220-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/13/2017] [Accepted: 02/28/2017] [Indexed: 12/01/2022]
Abstract
Studies by Bruce Ransom and colleagues have made a major contribution to show that white matter is susceptible to ischemia/hypoxia. White matter contains axons and the glia that support them, notably myelinating oligodendrocytes, which are highly vulnerable to ischemic-hypoxic damage. Previous studies have shown that metabotropic GluRs (mGluRs) are cytoprotective for oligodendrocyte precursor cells and immature oligodendrocytes, but their potential role in adult white matter was unresolved. Here, we report that group 1 mGluR1/5 and group 2 mGluR3 subunits are expressed in optic nerves from mice aged postnatal day (P)8-12 and P30-35. We demonstrate that activation of group 1 mGluR protects oligodendrocytes against oxygen-glucose deprivation (OGD) in developing and young adult optic nerves. In contrast, group 2 mGluR are shown to be protective for oligodendrocytes against OGD in postnatal but not young adult optic nerves. The cytoprotective effect of group 1 mGluR requires activation of PKC, whilst group 2 mGluR are dependent on negatively regulating adenylyl cyclase and cAMP. Our results identify a role for mGluR in limiting injury of oligodendrocytes in developing and young adult white matter, which may be useful for protecting oligodendrocytes in neuropathologies involving excitoxicity and ischemia/hypoxia.
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Affiliation(s)
- Arthur M Butt
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK.
| | - Ilaria Vanzulli
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Maria Papanikolaou
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Irene Chacon De La Rocha
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Virginia E Hawkins
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK. .,Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT, 06269, USA.
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