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Boyarko B, Podvin S, Greenberg B, Momper JD, Huang Y, Gerwick WH, Bang AG, Quinti L, Griciuc A, Kim DY, Tanzi RE, Feldman HH, Hook V. Evaluation of bumetanide as a potential therapeutic agent for Alzheimer's disease. Front Pharmacol 2023; 14:1190402. [PMID: 37601062 PMCID: PMC10436590 DOI: 10.3389/fphar.2023.1190402] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/28/2023] [Indexed: 08/22/2023] Open
Abstract
Therapeutics discovery and development for Alzheimer's disease (AD) has been an area of intense research to alleviate memory loss and the underlying pathogenic processes. Recent drug discovery approaches have utilized in silico computational strategies for drug candidate selection which has opened the door to repurposing drugs for AD. Computational analysis of gene expression signatures of patients stratified by the APOE4 risk allele of AD led to the discovery of the FDA-approved drug bumetanide as a top candidate agent that reverses APOE4 transcriptomic brain signatures and improves memory deficits in APOE4 animal models of AD. Bumetanide is a loop diuretic which inhibits the kidney Na+-K+-2Cl- cotransporter isoform, NKCC2, for the treatment of hypertension and edema in cardiovascular, liver, and renal disease. Electronic health record data revealed that patients exposed to bumetanide have lower incidences of AD by 35%-70%. In the brain, bumetanide has been proposed to antagonize the NKCC1 isoform which mediates cellular uptake of chloride ions. Blocking neuronal NKCC1 leads to a decrease in intracellular chloride and thus promotes GABAergic receptor mediated hyperpolarization, which may ameliorate disease conditions associated with GABAergic-mediated depolarization. NKCC1 is expressed in neurons and in all brain cells including glia (oligodendrocytes, microglia, and astrocytes) and the vasculature. In consideration of bumetanide as a repurposed drug for AD, this review evaluates its pharmaceutical properties with respect to its estimated brain levels across doses that can improve neurologic disease deficits of animal models to distinguish between NKCC1 and non-NKCC1 mechanisms. The available data indicate that bumetanide efficacy may occur at brain drug levels that are below those required for inhibition of the NKCC1 transporter which implicates non-NKCC1 brain mechansims for improvement of brain dysfunctions and memory deficits. Alternatively, peripheral bumetanide mechanisms may involve cells outside the central nervous system (e.g., in epithelia and the immune system). Clinical bumetanide doses for improved neurological deficits are reviewed. Regardless of mechanism, the efficacy of bumetanide to improve memory deficits in the APOE4 model of AD and its potential to reduce the incidence of AD provide support for clinical investigation of bumetanide as a repurposed AD therapeutic agent.
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Affiliation(s)
- Ben Boyarko
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Sonia Podvin
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Barry Greenberg
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jeremiah D. Momper
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Yadong Huang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, United States
- Departments of Neurology and Pathology, University of California, San Francisco, San Francisco, CA, United States
| | - William H. Gerwick
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States
| | - Anne G. Bang
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys, San Diego, CA, United States
| | - Luisa Quinti
- Genetics and Aging Research Unit, McCance Center for Brain Health, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Ana Griciuc
- Genetics and Aging Research Unit, McCance Center for Brain Health, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Doo Yeon Kim
- Genetics and Aging Research Unit, McCance Center for Brain Health, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Rudolph E. Tanzi
- Genetics and Aging Research Unit, McCance Center for Brain Health, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Howard H. Feldman
- Department of Neurosciences and Department of Pharmacology, University of California, San Diego, San Diego, United States
- Alzheimer’s Disease Cooperative Study, University of California, San Diego, La Jolla, CA, United States
| | - Vivian Hook
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
- Department of Neurosciences and Department of Pharmacology, University of California, San Diego, San Diego, United States
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Kurki SN, Uvarov P, Pospelov AS, Trontti K, Hübner AK, Srinivasan R, Watanabe M, Hovatta I, Hübner CA, Kaila K, Virtanen MA. Expression patterns of NKCC1 in neurons and non-neuronal cells during cortico-hippocampal development. Cereb Cortex 2022; 33:5906-5923. [PMID: 36573432 PMCID: PMC10183754 DOI: 10.1093/cercor/bhac470] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/05/2022] [Accepted: 11/06/2022] [Indexed: 12/28/2022] Open
Abstract
Abstract
The Na-K-2Cl cotransporter NKCC1 is widely expressed in cells within and outside the brain. However, our understanding of its roles in brain functions throughout development, as well as in neuropsychiatric and neurological disorders, has been severely hindered by the lack of reliable data on its developmental and (sub)cellular expression patterns. We provide here the first properly controlled analysis of NKCC1 protein expression in various cell types of the mouse brain using custom-made antibodies and an NKCC1 knock-out validated immunohistochemical procedure, with parallel data based on advanced mRNA approaches. NKCC1 protein and mRNA are expressed at remarkably high levels in oligodendrocytes. In immature neurons, NKCC1 protein was located in the somata, whereas in adult neurons, only NKCC1 mRNA could be clearly detected. NKCC1 immunoreactivity is also seen in microglia, astrocytes, developing pericytes, and in progenitor cells of the dentate gyrus. Finally, a differential expression of NKCC1 splice variants was observed, with NKCC1a predominating in non-neuronal cells and NKCC1b in neurons. Taken together, our data provide a cellular basis for understanding NKCC1 functions in the brain and enable the identification of major limitations and promises in the development of neuron-targeting NKCC1-blockers.
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Affiliation(s)
- Samu N Kurki
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Pavel Uvarov
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Alexey S Pospelov
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Kalevi Trontti
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
- University of Helsinki SleepWell Research Program, Faculty of Medicine, , 00014 Helsinki , Finland
- University of Helsinki Department of Psychology and Logopedics, , 00014 Helsinki , Finland
| | - Antje K Hübner
- Jena University Hospital, Friedrich Schiller Universität Institute of Human Genetics, , 07747 Jena , Germany
| | - Rakenduvadhana Srinivasan
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Masahiko Watanabe
- Hokkaido University Department of Anatomy, Faculty of Medicine, , Sapporo 060–8638 , Japan
| | - Iiris Hovatta
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
- University of Helsinki SleepWell Research Program, Faculty of Medicine, , 00014 Helsinki , Finland
- University of Helsinki Department of Psychology and Logopedics, , 00014 Helsinki , Finland
| | - Christian A Hübner
- Jena University Hospital, Friedrich Schiller Universität Institute of Human Genetics, , 07747 Jena , Germany
| | - Kai Kaila
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
| | - Mari A Virtanen
- University of Helsinki Molecular and Integrative Biosciences, , 00014 Helsinki , Finland
- Helsinki Institute of Life Science, University of Helsinki Neuroscience Center, , 00014 Helsinki , Finland
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3
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Leite JA, Pôças E, Maia GS, Barbosa L, Quintas LEM, Kawamoto EM, da Silva MLC, Scavone C, de Carvalho LED. Effect of ouabain on calcium signaling in rodent brain: A systematic review of in vitro studies. Front Pharmacol 2022; 13:916312. [PMID: 36105192 PMCID: PMC9465813 DOI: 10.3389/fphar.2022.916312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 07/20/2022] [Indexed: 11/26/2022] Open
Abstract
The Na+/K+-ATPase is an integral membrane ion pump, essential to maintaining osmotic balance in cells in the presence of cardiotonic steroids; more specifically, ouabain can be an endogenous modulator of the Na+/K+-ATPase. Here, we conducted a systematic review of the in vitro effects of cardiotonic steroids on Ca2+ in the brain of rats and mice. Methods: The review was carried out using the PubMed, Virtual Health Library, and EMBASE databases (between 12 June 2020 and 30 June 2020) and followed the guidelines described in the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Results: in total, 829 references were identified in the electronic databases; however, only 20 articles were considered, on the basis of the inclusion criteria. The studies demonstrated the effects of ouabain on Ca2+ signaling in synaptosomes, brain slices, and cultures of rat and mouse cells. In addition to the well-known cytotoxic effects of high doses of ouabain, resulting from indirect stimulation of the reverse mode of the Na+/Ca2+ exchanger and increased intracellular Ca2+, other effects have been reported. Ouabain-mediated Ca2+ signaling was able to act increasing cholinergic, noradrenergic and glutamatergic neurotransmission. Furthermore, ouabain significantly increased intracellular signaling molecules such as InsPs, IP3 and cAMP. Moreover treatment with low doses of ouabain stimulated myelin basic protein synthesis. Ouabain-induced intracellular Ca2+ increase may promote the activation of important cell signaling pathways involved in cellular homeostasis and function. Thus, the study of the application of ouabain in low doses being promising for application in neurological diseases. Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020204498, identifier CRD42020204498.
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Affiliation(s)
- Jacqueline Alves Leite
- Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Elisa Pôças
- Campus Realengo, Instituto Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gisele Silva Maia
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Campus Centro-Oeste Dona Lindu, São Paulo, Brazil
| | - Leandro Barbosa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Campus Centro-Oeste Dona Lindu, São Paulo, Brazil
| | - Luis Eduardo M. Quintas
- Laboratório de Farmacologia Bioquímica e Molecular, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Elisa Mitiko Kawamoto
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | | | - Cristoforo Scavone
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Luciana E. Drumond de Carvalho
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Campus Centro-Oeste Dona Lindu, São Paulo, Brazil
- *Correspondence: Luciana E. Drumond de Carvalho,
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Löscher W, Kaila K. CNS pharmacology of NKCC1 inhibitors. Neuropharmacology 2021; 205:108910. [PMID: 34883135 DOI: 10.1016/j.neuropharm.2021.108910] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 11/25/2021] [Accepted: 11/26/2021] [Indexed: 12/21/2022]
Abstract
The Na-K-2Cl cotransporter NKCC1 and the neuron-specific K-Cl cotransporter KCC2 are considered attractive CNS drug targets because altered neuronal chloride regulation and consequent effects on GABAergic signaling have been implicated in numerous CNS disorders. While KCC2 modulators are not yet clinically available, the loop diuretic bumetanide has been used off-label in attempts to treat brain disorders and as a tool for NKCC1 inhibition in preclinical models. Bumetanide is known to have anticonvulsant and neuroprotective effects under some pathophysiological conditions. However, as shown in several species from neonates to adults (mice, rats, dogs, and by extrapolation in humans), at the low clinical doses of bumetanide approved for diuresis, this drug has negligible access into the CNS, reaching levels that are much lower than what is needed to inhibit NKCC1 in cells within the brain parenchyma. Several drug discovery strategies have been initiated over the last ∼15 years to develop brain-permeant compounds that, ideally, should be selective for NKCC1 to eliminate the diuresis mediated by inhibition of renal NKCC2. The strategies employed to improve the pharmacokinetic and pharmacodynamic properties of NKCC1 blockers include evaluation of other clinically approved loop diuretics; development of lipophilic prodrugs of bumetanide; development of side-chain derivatives of bumetanide; and unbiased high-throughput screening approaches of drug discovery based on large chemical compound libraries. The main outcomes are that (1), non-acidic loop diuretics such as azosemide and torasemide may have advantages as NKCC1 inhibitors vs. bumetanide; (2), bumetanide prodrugs lead to significantly higher brain levels than the parent drug and have lower diuretic activity; (3), the novel bumetanide side-chain derivatives do not exhibit any functionally relevant improvement of CNS accessibility or NKCC1 selectivity vs. bumetanide; (4) novel compounds discovered by high-throughput screening may resolve some of the inherent problems of bumetanide, but as yet this has not been achieved. Thus, further research is needed to optimize the design of brain-permeant NKCC1 inhibitors. In parallel, a major challenge is to identify the mechanisms whereby various NKCC1-expressing cellular targets of these drugs within (e.g., neurons, oligodendrocytes or astrocytes) and outside the brain parenchyma (e.g., the blood-brain barrier, the choroid plexus, and the endocrine system), as well as molecular off-target effects, might contribute to their reported therapeutic and adverse effects.
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Affiliation(s)
- Wolfgang Löscher
- Dept. of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience Hannover, Germany.
| | - Kai Kaila
- Molecular and Integrative Biosciences and Neuroscience Center (HiLIFE), University of Helsinki, Finland
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5
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Podbielska M, O’Keeffe J, Pokryszko-Dragan A. New Insights into Multiple Sclerosis Mechanisms: Lipids on the Track to Control Inflammation and Neurodegeneration. Int J Mol Sci 2021; 22:ijms22147319. [PMID: 34298940 PMCID: PMC8303889 DOI: 10.3390/ijms22147319] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 12/19/2022] Open
Abstract
Multiple sclerosis (MS) is a central nervous system disease with complex pathogenesis, including two main processes: immune-mediated inflammatory demyelination and progressive degeneration with axonal loss. Despite recent progress in our understanding and management of MS, availability of sensitive and specific biomarkers for these both processes, as well as neuroprotective therapeutic options targeted at progressive phase of disease, are still being sought. Given their abundance in the myelin sheath, lipids are believed to play a central role in underlying immunopathogenesis in MS and seem to be a promising subject of investigation in this field. On the basis of our previous research and a review of the literature, we discuss the current understanding of lipid-related mechanisms involved in active relapse, remission, and progression of MS. These insights highlight potential usefulness of lipid markers in prediction or monitoring the course of MS, particularly in its progressive stage, still insufficiently addressed. Furthermore, they raise hope for new, effective, and stage-specific treatment options, involving lipids as targets or carriers of therapeutic agents.
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Affiliation(s)
- Maria Podbielska
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
- Laboratory of Microbiome Immunobiology, Ludwik Hirszfeld Institute of Immunology & Experimental Therapy, Polish Academy of Sciences, 53-114 Wroclaw, Poland
- Correspondence: ; Tel.: +48-71-370-9912
| | - Joan O’Keeffe
- Department of Analytical, Biopharmaceutical and Medical Sciences, School of Science & Computing, Galway-Mayo Institute of Technology, Galway, Ireland;
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GluA2 overexpression in oligodendrocyte progenitors promotes postinjury oligodendrocyte regeneration. Cell Rep 2021; 35:109147. [PMID: 34010640 PMCID: PMC8185898 DOI: 10.1016/j.celrep.2021.109147] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/28/2020] [Accepted: 04/27/2021] [Indexed: 01/18/2023] Open
Abstract
Oligodendrocyte precursor cells (OPCs) are essential for developmental myelination and oligodendrocyte regeneration after CNS injury. These progenitors express calcium-permeable AMPA receptors (AMPARs) and form direct synapses with neurons throughout the CNS, but the roles of this signaling are unclear. To enable selective alteration of the properties of AMPARs in oligodendroglia, we generate mice that allow cell-specific overexpression of EGFP-GluA2 in vivo. In healthy conditions, OPC-specific GluA2 overexpression significantly increase their proliferation in an age-dependent manner but did not alter their rate of differentiation into oligodendrocytes. In contrast, after demyelinating brain injury in neonates or adults, higher GluA2 levels promote both OPC proliferation and oligodendrocyte regeneration, but do not prevent injury-induced initial cell loss. These findings indicate that AMPAR GluA2 content regulates the proliferative and regenerative behavior of adult OPCs, serving as a putative target for better myelin repair.
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7
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Spencer SA, Suárez-Pozos E, Escalante M, Myo YP, Fuss B. Sodium-Calcium Exchangers of the SLC8 Family in Oligodendrocytes: Functional Properties in Health and Disease. Neurochem Res 2020; 45:1287-1297. [PMID: 31927687 DOI: 10.1007/s11064-019-02949-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 12/20/2019] [Accepted: 12/23/2019] [Indexed: 12/30/2022]
Abstract
The solute carrier 8 (SLC8) family of sodium-calcium exchangers (NCXs) functions as an essential regulatory system that couples opposite fluxes of sodium and calcium ions across plasmalemmal membranes. NCXs, thereby, play key roles in maintaining an ion homeostasis that preserves cellular integrity. Hence, alterations in NCX expression and regulation have been found to lead to ionic imbalances that are often associated with intracellular calcium overload and cell death. On the other hand, intracellular calcium has been identified as a key driver for a multitude of downstream signaling events that are crucial for proper functioning of biological systems, thus highlighting the need for a tightly controlled balance. In the CNS, NCXs have been primarily characterized in the context of synaptic transmission and ischemic brain damage. However, a much broader picture is emerging. NCXs are expressed by virtually all cells of the CNS including oligodendrocytes (OLGs), the cells that generate the myelin sheath. With a growing appreciation of dynamic calcium signals in OLGs, NCXs are becoming increasingly recognized for their crucial roles in shaping OLG function under both physiological and pathophysiological conditions. In order to provide a current update, this review focuses on the importance of NCXs in cells of the OLG lineage. More specifically, it provides a brief introduction into plasmalemmal NCXs and their modes of activity, and it discusses the roles of OLG expressed NCXs in regulating CNS myelination and in contributing to CNS pathologies associated with detrimental effects on OLG lineage cells.
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Affiliation(s)
- Samantha A Spencer
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA, 23298, USA
| | - Edna Suárez-Pozos
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA, 23298, USA
| | - Miguel Escalante
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA, 23298, USA.,Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Yu Par Myo
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA, 23298, USA
| | - Babette Fuss
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA, 23298, USA.
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8
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Song S, Luo L, Sun B, Sun D. Roles of glial ion transporters in brain diseases. Glia 2019; 68:472-494. [PMID: 31418931 DOI: 10.1002/glia.23699] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/22/2019] [Accepted: 07/26/2019] [Indexed: 12/21/2022]
Abstract
Glial ion transporters are important in regulation of ionic homeostasis, cell volume, and cellular signal transduction under physiological conditions of the central nervous system (CNS). In response to acute or chronic brain injuries, these ion transporters can be activated and differentially regulate glial functions, which has subsequent impact on brain injury or tissue repair and functional recovery. In this review, we summarized the current knowledge about major glial ion transporters, including Na+ /H+ exchangers (NHE), Na+ /Ca2+ exchangers (NCX), Na+ -K+ -Cl- cotransporters (NKCC), and Na+ -HCO3 - cotransporters (NBC). In acute neurological diseases, such as ischemic stroke and traumatic brain injury (TBI), these ion transporters are rapidly activated and play significant roles in regulation of the intra- and extracellular pH, Na+ , K+ , and Ca2+ homeostasis, synaptic plasticity, and myelin formation. However, overstimulation of these ion transporters can contribute to glial apoptosis, demyelination, inflammation, and excitotoxicity. In chronic brain diseases, such as glioma, Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS), glial ion transporters are involved in the glioma Warburg effect, glial activation, neuroinflammation, and neuronal damages. These findings suggest that glial ion transporters are involved in tissue structural and functional restoration, or brain injury and neurological disease development and progression. A better understanding of these ion transporters in acute and chronic neurological diseases will provide insights for their potential as therapeutic targets.
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Affiliation(s)
- Shanshan Song
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Lanxin Luo
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania.,School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China.,School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, China
| | - Baoshan Sun
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, China.,Pólo Dois Portos, Instituto National de Investigação Agrária e Veterinária, Dois Portos, Portugal
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania.,Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, Pennsylvania
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Zhang M, Liu Y, Wu S, Zhao X. Ca 2+ Signaling in Oligodendrocyte Development. Cell Mol Neurobiol 2019; 39:1071-1080. [PMID: 31222426 DOI: 10.1007/s10571-019-00705-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/11/2019] [Indexed: 12/31/2022]
Abstract
Calcium signaling has essential roles in the development of the nervous system, from neural induction to the proliferation, migration, and differentiation of both neuronal and glia cells. The temporal and spatial dynamics of Ca2+ signals control the highly diverse yet specific transcriptional programs that establish the complex structures of the nervous system. Ca2+-signaling pathways are shaped by interactions among metabotropic signaling cascades, ion channels, intracellular Ca2+ stores, and a multitude of downstream effector proteins that activate specific genetic programs. Progress in the last decade has led to significant advances in our understanding of the functional architecture of Ca2+ signaling networks involved in oligodendrocyte development. In this review, we summarize the molecular and functional organizations of Ca2+-signaling networks during the differentiation of oligodendrocyte, especially its impact on myelin gene expression, proliferation, migration, and myelination. Importantly, the existence of multiple routes of Ca2+ influx opens the possibility that the activity of calcium channels can be manipulated pharmacologically to encourage oligodendrocyte maturation and remyelination after demyelinating episodes in the brain.
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Affiliation(s)
- Ming Zhang
- Department of Neurobiology, Collaborative Innovation Center for Brain Science and Shaanxi Key Laboratory of Brain Disorders, Fourth Military Medical University, Xi'an, 710032, China
| | - Yuming Liu
- Department of Neurobiology, Collaborative Innovation Center for Brain Science and Shaanxi Key Laboratory of Brain Disorders, Fourth Military Medical University, Xi'an, 710032, China
| | - Shengxi Wu
- Department of Neurobiology, Collaborative Innovation Center for Brain Science and Shaanxi Key Laboratory of Brain Disorders, Fourth Military Medical University, Xi'an, 710032, China.
| | - Xianghui Zhao
- Department of Neurobiology, Collaborative Innovation Center for Brain Science and Shaanxi Key Laboratory of Brain Disorders, Fourth Military Medical University, Xi'an, 710032, China.
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10
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Hammann J, Bassetti D, White R, Luhmann HJ, Kirischuk S. α2 isoform of Na +,K +-ATPase via Na +,Ca 2+ exchanger modulates myelin basic protein synthesis in oligodendrocyte lineage cells in vitro. Cell Calcium 2018; 73:1-10. [PMID: 29880193 DOI: 10.1016/j.ceca.2018.03.003] [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: 01/31/2018] [Revised: 03/05/2018] [Accepted: 03/25/2018] [Indexed: 11/26/2022]
Abstract
Oligodendrocytes in the CNS myelinate neuronal axons, facilitating rapid propagation of action potentials. Myelin basic protein (MBP) is an essential component of myelin and its absence results in severe hypomyelination. In oligodendrocyte lineage cell (OLC) monocultures MBP synthesis starts at DIV4. Ouabain (10 nM), a Na+,K+-ATPase (NKA) blocker, stimulates MBP synthesis. As OLCs express the α2 isoform of NKA (α2-NKA) that has a high affinity for ouabain, we hypothesized that α2-NKA mediates this effect. Knockdown of α2-NKA with small interfering (si)RNA (α2-siRNA) significantly potentiated MBP synthesis at DIV4 and 5. This effect was completely blocked by KB-R7943 (1 μM), a Na+,Ca2+ exchanger (NCX) antagonist. α2-NKA ablation increased the frequency of NCX-mediated spontaneous Ca2+ transients ([Ca2+]t) at DIV4, whereas in control OLC cultures comparable frequency of [Ca2+]t was observed at DIV5. At DIV6 almost no [Ca2+]t were observed either in control or in α2-siRNA-treated cultures. Immunocytochemical analyses showed that α2-NKA co-localizes with MBP in proximal processes of immature OLCs but is only weakly present in MBP-enriched membrane sheets. Knockdown of α2-NKA in cortical slice cultures did not change MBP levels but reduced co-localization of neurofilament- and MBP-positive compartments. We conclude that α2-NKA activity in OLCs affects NCX-mediated [Ca2+]t and the onset of MBP synthesis. We suggest therefore that neuronal activity, presumably in form of local extracellular [K+] changes, might locally influence NCX-mediated [Ca2+]t in OLC processes thus triggering local MBP synthesis in the vicinity of an active axon.
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Affiliation(s)
- Jens Hammann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Davide Bassetti
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Robin White
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany
| | - Sergei Kirischuk
- Institute of Physiology, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, D-55128 Mainz, Germany.
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11
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Chaban YHG, Chen Y, Hertz E, Hertz L. Severe Convulsions and Dysmyelination in Both Jimpy and Cx32/47 -/- Mice may Associate Astrocytic L-Channel Function with Myelination and Oligodendrocytic Connexins with Internodal K v Channels. Neurochem Res 2017; 42:1747-1766. [PMID: 28214987 DOI: 10.1007/s11064-017-2194-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 12/12/2022]
Abstract
The Jimpy mouse illustrates the importance of interactions between astrocytes and oligodendrocytes. It has a mutation in Plp coding for proteolipid protein and DM20. Its behavior is normal at birth but from the age of ~2 weeks it shows severe convulsions associated with oligodendrocyte/myelination deficits and early death. A normally occurring increase in oxygen consumption by highly elevated K+ concentrations is absent in Jimpy brain slices and cultured astrocytes, reflecting that Plp at early embryonic stages affects common precursors as also shown by the ability of conditioned medium from normal astrocytes to counteract histological abnormalities. This metabolic response is now known to reflect opening of L-channels for Ca2+. The resulting deficiency in Ca2+ entry has many consequences, including lack of K+-stimulated glycogenolysis and release of gliotransmitter ATP. Lack of purinergic stimulation compromises oligodendrocyte survival and myelination and affects connexins and K+ channels. Mice lacking the oligodendrocytic connexins Cx32 and 47 show similar neurological dysfunction as Jimpy. This possibly reflects that K+ released by intermodal axonal Kv channels is transported underneath a loosened myelin sheath instead of reaching the extracellular space via connexin-mediated transport to oligodendrocytes, followed by release and astrocytic Na+,K+-ATPase-driven uptake with subsequent Kir4.1-facilitated release and neuronal uptake.
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Affiliation(s)
| | - Ye Chen
- Henry M. Jackson Foundation, Bethesda, MD, 20817, USA
| | - Elna Hertz
- Laboratory of Metabolic Brain Diseases, Institute of Metabolic Disease Research and Drug Development, China Medical University, Shenyang, People's Republic of China
| | - Leif Hertz
- Laboratory of Metabolic Brain Diseases, Institute of Metabolic Disease Research and Drug Development, China Medical University, Shenyang, People's Republic of China.
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12
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Astrocyte Sodium Signalling and Panglial Spread of Sodium Signals in Brain White Matter. Neurochem Res 2017; 42:2505-2518. [PMID: 28214986 DOI: 10.1007/s11064-017-2197-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/19/2017] [Accepted: 01/28/2017] [Indexed: 10/20/2022]
Abstract
In brain grey matter, excitatory synaptic transmission activates glutamate uptake into astrocytes, inducing sodium signals which propagate into neighboring astrocytes through gap junctions. These sodium signals have been suggested to serve an important role in neuro-metabolic coupling. So far, it is unknown if astrocytes in white matter-that is in brain regions devoid of synapses-are also able to undergo such intra- and intercellular sodium signalling. In the present study, we have addressed this question by performing quantitative sodium imaging in acute tissue slices of mouse corpus callosum. Focal application of glutamate induced sodium transients in SR101-positive astrocytes. These were largely unaltered in the presence of ionotropic glutamate receptors blockers, but strongly dampened upon pharmacological inhibition of glutamate uptake. Sodium signals induced in individual astrocytes readily spread into neighboring SR101-positive cells with peak amplitudes decaying monoexponentially with distance from the stimulated cell. In addition, spread of sodium was largely unaltered during pharmacological inhibition of purinergic and glutamate receptors, indicating gap junction-mediated, passive diffusion of sodium between astrocytes. Using cell-type-specific, transgenic reporter mice, we found that sodium signals also propagated, albeit less effectively, from astrocytes to neighboring oligodendrocytes and NG2 cells. Again, panglial spread was unaltered with purinergic and glutamate receptors blocked. Taken together, our results demonstrate that activation of sodium-dependent glutamate transporters induces sodium signals in white matter astrocytes, which spread within the astrocyte syncytium. In addition, we found a panglial passage of sodium signals from astrocytes to NG2 cells and oligodendrocytes, indicating functional coupling between these macroglial cells in white matter.
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13
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Zhao H, Nepomuceno R, Gao X, Foley LM, Wang S, Begum G, Zhu W, Pigott VM, Falgoust LM, Kahle KT, Yang SS, Lin SH, Alper SL, Hitchens TK, Hu S, Zhang Z, Sun D. Deletion of the WNK3-SPAK kinase complex in mice improves radiographic and clinical outcomes in malignant cerebral edema after ischemic stroke. J Cereb Blood Flow Metab 2017; 37:550-563. [PMID: 26861815 PMCID: PMC5381450 DOI: 10.1177/0271678x16631561] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The WNK-SPAK kinase signaling pathway controls renal NaCl reabsorption and systemic blood pressure by regulating ion transporters and channels. A WNK3-SPAK complex is highly expressed in brain, but its function in this organ remains unclear. Here, we investigated the role of this kinase complex in brain edema and white matter injury after ischemic stroke. Wild-type, WNK3 knockout, and SPAK heterozygous or knockout mice underwent transient middle cerebral artery occlusion. One cohort of mice underwent magnetic resonance imaging. Ex-vivo brains three days post-ischemia were imaged by slice-selective spin-echo diffusion tensor imaging magnetic resonance imaging, after which the same brain tissues were subjected to immunofluorescence staining. A second cohort of mice underwent neurological deficit analysis up to 14 days post-transient middle cerebral artery occlusion. Relative to wild-type mice, WNK3 knockout, SPAK heterozygous, and SPAK knockout mice each exhibited a >50% reduction in infarct size and associated cerebral edema, significantly less demyelination, and improved neurological outcomes. We conclude that WNK3-SPAK signaling regulates brain swelling, gray matter injury, and demyelination after ischemic stroke, and that WNK3-SPAK inhibition has therapeutic potential for treating malignant cerebral edema in the setting of middle cerebral artery stroke.
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Affiliation(s)
- Hanshu Zhao
- 1 Department of Neurology, the First Affiliated Hospital of the Harbin Medical University, Harbin, China.,2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Rachel Nepomuceno
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Xin Gao
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA.,3 Department of Neurological Surgery, the Second Affiliated Hospital of the Harbin Medical University, Harbin, China
| | - Lesley M Foley
- 4 Animal Imaging Center, University of Pittsburgh, Pittsburgh, USA
| | - Shaoxia Wang
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Gulnaz Begum
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Wen Zhu
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Victoria M Pigott
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | | | - Kristopher T Kahle
- 6 Department of Neurosurgery, Yale School of Medicine, New Haven, USA.,7 Department of Pediatrics, Yale School of Medicine, New Haven, USA.,8 Yale Program on Neurogenetics, Yale School of Medicine, New Haven, USA
| | - Sung-Sen Yang
- 9 Division of Nephrology, Department of Medicine, Tri-Service General Hospital, Taipei, Taiwan.,10 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Shih-Hua Lin
- 9 Division of Nephrology, Department of Medicine, Tri-Service General Hospital, Taipei, Taiwan.,10 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Seth L Alper
- 11 Division of Nephrology, Beth Israel Deaconess Medical Center, Boston, USA.,12 Department of Medicine, Harvard Medical School, Boston, USA
| | - T Kevin Hitchens
- 4 Animal Imaging Center, University of Pittsburgh, Pittsburgh, USA.,5 Department of Neurobiology, University of Pittsburgh, Pittsburgh, USA
| | - Shaoshan Hu
- 3 Department of Neurological Surgery, the Second Affiliated Hospital of the Harbin Medical University, Harbin, China
| | - Zhongling Zhang
- 1 Department of Neurology, the First Affiliated Hospital of the Harbin Medical University, Harbin, China
| | - Dandan Sun
- 2 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
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14
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Hertz L, Chen Y. Importance of astrocytes for potassium ion (K+) homeostasis in brain and glial effects of K+ and its transporters on learning. Neurosci Biobehav Rev 2016; 71:484-505. [DOI: 10.1016/j.neubiorev.2016.09.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/12/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
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15
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The pathophysiological role of astrocytic endothelin-1. Prog Neurobiol 2016; 144:88-102. [DOI: 10.1016/j.pneurobio.2016.04.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/23/2016] [Accepted: 04/25/2016] [Indexed: 12/13/2022]
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16
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Boscia F, Begum G, Pignataro G, Sirabella R, Cuomo O, Casamassa A, Sun D, Annunziato L. Glial Na(+) -dependent ion transporters in pathophysiological conditions. Glia 2016; 64:1677-97. [PMID: 27458821 DOI: 10.1002/glia.23030] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/22/2016] [Accepted: 06/29/2016] [Indexed: 12/12/2022]
Abstract
Sodium dynamics are essential for regulating functional processes in glial cells. Indeed, glial Na(+) signaling influences and regulates important glial activities, and plays a role in neuron-glia interaction under physiological conditions or in response to injury of the central nervous system (CNS). Emerging studies indicate that Na(+) pumps and Na(+) -dependent ion transporters in astrocytes, microglia, and oligodendrocytes regulate Na(+) homeostasis and play a fundamental role in modulating glial activities in neurological diseases. In this review, we first briefly introduced the emerging roles of each glial cell type in the pathophysiology of cerebral ischemia, Alzheimer's disease, epilepsy, Parkinson's disease, Amyotrophic Lateral Sclerosis, and myelin diseases. Then, we discussed the current knowledge on the main roles played by the different glial Na(+) -dependent ion transporters, including Na(+) /K(+) ATPase, Na(+) /Ca(2+) exchangers, Na(+) /H(+) exchangers, Na(+) -K(+) -Cl(-) cotransporters, and Na(+) - HCO3- cotransporter in the pathophysiology of the diverse CNS diseases. We highlighted their contributions in cell survival, synaptic pathology, gliotransmission, pH homeostasis, and their role in glial activation, migration, gliosis, inflammation, and tissue repair processes. Therefore, this review summarizes the foundation work for targeting Na(+) -dependent ion transporters in glia as a novel strategy to control important glial activities associated with Na(+) dynamics in different neurological disorders. GLIA 2016;64:1677-1697.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Gulnaz Begum
- Department of Neurology, University of Pittsburgh Medical School
| | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Rossana Sirabella
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Antonella Casamassa
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh Medical School.,Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, Pennsylvania, 15213
| | - Lucio Annunziato
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
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17
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Intracellular ion signaling influences myelin basic protein synthesis in oligodendrocyte precursor cells. Cell Calcium 2016; 60:322-330. [PMID: 27417499 DOI: 10.1016/j.ceca.2016.06.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 06/28/2016] [Accepted: 06/28/2016] [Indexed: 11/20/2022]
Abstract
Myelination in the central nervous system depends on axon-oligodendrocyte precursor cell (OPC) interaction. We suggest that myelin synthesis may be influenced by [Na+]i and [Ca2+]i signaling in OPCs. Experiments were performed in mouse cultured OPCs at day in vitro (DIV) 2-6 or acute slices of the corpus callosum at postnatal days (P) 10-30. Synthesis of Myelin Basic Protein (MBP), an "executive molecule of myelin", was used as readout of myelination. Immunohistological data revealed that MBP synthesis in cultured OPCs starts around DIV4. Transient elevations of resting [Ca2+]i and [Na+]i levels were observed in the same temporal window (DIV4-5). At DIV4, but not at DIV2, both extracellular [K+] ([K+]e) elevation (+5mM) and partial Na+,K+-ATPase (NKA) inhibition elicited [Na+]i and [Ca2+]i transients. These responses were blocked with KB-R7943 (1μM), a blocker of Na+-Ca2+ exchanger (NCX), indicating an involvement of NCX which operates in reverse mode. Treatment of OPCs with culture medium containing elevated [K+] (+5mM, 24h) or ouabain (500nM, 24h) increased resting [Ca2+]i and facilitated MBP synthesis. Blockade of NCX with KB-R7943 (1μM, 12h) reduced resting [Ca2+]i and decreased MBP synthesis. Similar to the results obtained in OPC cultures, OPCs in acute callosal slices demonstrated an increase in resting [Ca2+]i and [Na+]i levels during development. NCX blockade induced [Ca2+]i and [Na+]i responses in OPCs at P20-30 but not at P10. We conclude that local [Na+]i and/or membrane potential changes can modulate Ca2+ influx through NCX and in turn MBP synthesis. Thus neuronal activity-induced changes in [K+]e may via NCX and NKA modulate myelination.
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18
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Parpura V, Sekler I, Fern R. Plasmalemmal and mitochondrial Na+-Ca2+exchange in neuroglia. Glia 2016; 64:1646-54. [DOI: 10.1002/glia.22975] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 01/07/2016] [Accepted: 01/25/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Vladimir Parpura
- Department of Neurobiology; Center for Glial Biology in Medicine, Civitan International Research Center, Atomic Force Microscopy & Nanotechnology Laboratories, and Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham; Birmingham Alabama
| | - Israel Sekler
- Department of Physiology, Faculty of Health Science; Ben-Gurion University; Ben-Guion Av 84105 POB 653
| | - Robert Fern
- Peninsular School of Medicine and Dentistry; University of Plymouth; Plymouth PL6 8BU United Kingdom
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19
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Tang BL. (WNK)ing at death: With-no-lysine (Wnk) kinases in neuropathies and neuronal survival. Brain Res Bull 2016; 125:92-8. [PMID: 27131446 DOI: 10.1016/j.brainresbull.2016.04.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 04/11/2016] [Accepted: 04/24/2016] [Indexed: 12/22/2022]
Abstract
Members of With-no-lysine (WNK) family of serine-threonine kinase are key regulators of chloride ion transport in diverse cell types, controlling the activity and the surface expression of cation-chloride (Na(+)/K(+)-Cl(-)) co-transporters. Mutations in WNK1 and WNK4 are linked to a hereditary form of hypertension, and WNKs have been extensively investigated pertaining to their roles in renal epithelial ion homeostasis. However, some members of the WNK family and their splice isoforms are also expressed in the mammalian brain, and have been implicated in aspects of hereditary neuropathy as well as neuronal and glial survival. WNK2, which is exclusively enriched in neurons, is well known as an anti-proliferative tumor suppressor. WNK3, on the other hand, appears to promote cell survival as its inhibition enhances neuronal apoptosis. However, loss of WNK3 has been recently shown to reduce ischemia-associated brain damage. In this review, I surveyed the potentially context-dependent roles of WNKs in neurological disorders and neuronal survival.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore.
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20
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Hui H, Rao W, Zhang L, Xie Z, Peng C, Su N, Wang K, Wang L, Luo P, Hao YL, Zhang S, Fei Z. Inhibition of Na(+)-K(+)-2Cl(-) Cotransporter-1 attenuates traumatic brain injury-induced neuronal apoptosis via regulation of Erk signaling. Neurochem Int 2016; 94:23-31. [PMID: 26854573 DOI: 10.1016/j.neuint.2016.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/26/2016] [Accepted: 02/03/2016] [Indexed: 11/28/2022]
Abstract
Traumatic brain injury (TBI) is the leading cause of mortality and morbidity worldwide and is characterized by immediate brain damage and secondary injuries, such as brain edema and ischemia. However, the exact pathological mechanisms that comprise these associated secondary injuries have not been fully elucidated. This study aimed to investigate the role of the Na(+)-K(+)-2Cl(-) cotransporter-1 (NKCC1) in the disruption of ion homeostasis and neuronal apoptosis in TBI. Using a traumatic neuron injury (TNI) model in vitro and a controlled cortex injury (CCI) model in vivo, the present study investigated changes in the expression and effects of NKCC1 in TBI using western blot, RNA interference, a lactate dehydrogenase (LDH) release assay, TdT-mediated dUTP Nick end-labeling (TUNEL) analysis, sodium imaging, brain water content, and neurological severity scoring. TBI induced the expression of NKCC1 to be significantly upregulated in the cortex, both in vitro and in vivo. Pharmacological inhibitor bumetanide (Bume) or NKCC1 RNA interference significantly attenuated TBI-induced intracellular Na(+) increase, inhibited neuronal apoptosis, and improved brain edema and neurological function. Furthermore, NKCC1 inhibition also significantly inhibited TBI-induced extracellular signal-regulated kinase (Erk) activation. Erk inhibition significantly protected neurons from TBI injury; however, Erk inhibition had no effect on NKCC1 expression or the neuroprotective effect of NKCC1 inhibition against TBI. This study demonstrates the role of NKCC1 in TBI-induced brain cortex injury, establishing that NKCC1 may play a neurotoxic role in TBI and that the inhibition of NKCC1 may protect neurons from TBI via the regulation of Erk signaling.
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Affiliation(s)
- Hao Hui
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Wei Rao
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Lei Zhang
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Zhen Xie
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Cheng Peng
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Ning Su
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Kai Wang
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Li Wang
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Peng Luo
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Ye-lu Hao
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China
| | - Sai Zhang
- Department of Neurosurgery, Affiliated Hospital of Logistics, University of Chinese Armed Police Forces, Chenglin Road, Tianjin 300162, PR China.
| | - Zhou Fei
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, PR China.
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21
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Sharma V, O'Halloran DM. Nematode Sodium Calcium Exchangers: A Surprising Lack of Transport. Bioinform Biol Insights 2016; 10:1-4. [PMID: 26848260 PMCID: PMC4737524 DOI: 10.4137/bbi.s37130] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/28/2015] [Accepted: 01/02/2016] [Indexed: 12/14/2022] Open
Abstract
Na+/Ca2+ exchangers are low-affinity, high-capacity transporters that rapidly transport calcium against a gradient of Na+ ions. Na+/Ca2+ exchangers are divided into three groups based upon substrate specificity: Na+/Ca2+ exchangers (NCX), Na+/Ca2+/K+ exchangers (NCKX), and Ca2+/cation exchangers (NCLX). In mammals, there are three NCX genes, five NCKX genes, and a single NCLX gene. The genome of the nematode Caenorhabditis elegans contains 10 Na+/Ca2+ exchanger genes: three NCX, five NCLX, and two NCKX genes. In a previous study, we characterized the structural and taxonomic specializations within the family of Na+/Ca2+ exchangers across the phylum Nematoda and observed a complex picture of Na+/Ca2+ exchanger evolution across diverse nematode species. We noted multiple cases of putative gene gain and loss and, most surprisingly, did not detect members of the NCLX type of exchangers within subsets of nematode species. In this commentary, we discuss these findings and speculate on the functional outcomes and physiology of these observations. Our data highlight the importance of studying diverse systems in order to get a deeper understanding of the evolution and regulation of Ca2+ signaling critical for animal function.
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Affiliation(s)
- Vishal Sharma
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - Damien M O'Halloran
- Department of Biological Sciences, The George Washington University, Washington, DC, USA.; Institute for Neuroscience, The George Washington University, Washington, DC, USA
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22
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Begum G, Yuan H, Kahle KT, Li L, Wang S, Shi Y, Shmukler BE, Yang SS, Lin SH, Alper SL, Sun D. Inhibition of WNK3 Kinase Signaling Reduces Brain Damage and Accelerates Neurological Recovery After Stroke. Stroke 2015; 46:1956-1965. [PMID: 26069258 DOI: 10.1161/strokeaha.115.008939] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 05/14/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE WNK kinases, including WNK3, and the associated downstream Ste20/SPS1-related proline-alanine-rich protein kinase (SPAK) and oxidative stress responsive 1 (OSR1) kinases, comprise an important signaling cascade that regulates the cation-chloride cotransporters. Ischemia-induced stimulation of the bumetanide-sensitive Na(+)-K(+)-Cl(-) cotransporter (NKCC1) plays an important role in the pathophysiology of experimental stroke, but the mechanism of its regulation in this context is unknown. Here, we investigated the WNK3-SPAK/OSR1 pathway as a regulator of NKCC1 stimulation and their collective role in ischemic brain damage. METHOD Wild-type WNK3 and WNK3 knockout mice were subjected to ischemic stroke via transient middle cerebral artery occlusion. Infarct volume, brain edema, blood brain barrier damage, white matter demyelination, and neurological deficits were assessed. Total and phosphorylated forms of WNK3 and SPAK/OSR1 were assayed by immunoblotting and immunostaining. In vitro ischemia studies in cultured neurons and immature oligodendrocytes were conducted using the oxygen-glucose deprivation/reoxygenation method. RESULTS WNK3 knockout mice exhibited significantly decreased infarct volume and axonal demyelination, less cerebral edema, and accelerated neurobehavioral recovery compared with WNK3 wild-type mice subjected to middle cerebral artery occlusion. The neuroprotective phenotypes conferred by WNK3 knockout were associated with a decrease in stimulatory hyperphosphorylations of the SPAK/OSR1 catalytic T-loop and of NKCC1 stimulatory sites Thr(203)/Thr(207)/Thr(212), as well as with decreased cell surface expression of NKCC1. Genetic inhibition of WNK3 or small interfering RNA knockdown of SPAK/OSR1 increased the tolerance of cultured primary neurons and oligodendrocytes to in vitro ischemia. CONCLUSIONS These data identify a novel role for the WNK3-SPAK/OSR1-NKCC1 signaling pathway in ischemic neuroglial injury and suggest the WNK3-SPAK/OSR1 kinase pathway as a therapeutic target for neuroprotection after ischemic stroke.
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Affiliation(s)
- Gulnaz Begum
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Hui Yuan
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Kristopher T Kahle
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Liaoliao Li
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Shaoxia Wang
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Yejie Shi
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Boris E Shmukler
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Sung-Sen Yang
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Shih-Hua Lin
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Seth L Alper
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, (G.B., H.Y., L.L., S.W., Y.S., D.S.); Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA (K.T.K.); Manton Center for Orphan Diseases, Harvard Medical School, MA (K.T.K.); Renal Division and Vascular Biology Center, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, MA (B.E.S., S.L.A); Division of Nephrology, Dept. of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (SS.Y., SH.L); Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA (D.S)
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Jantzie LL, Hu MY, Park HK, Jackson MC, Yu J, Maxwell JR, Jensen FE. Chloride cotransporter NKCC1 inhibitor bumetanide protects against white matter injury in a rodent model of periventricular leukomalacia. Pediatr Res 2015; 77:554-62. [PMID: 25585037 DOI: 10.1038/pr.2015.9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/25/2014] [Indexed: 01/19/2023]
Abstract
BACKGROUND Periventricular leukomalacia (PVL) is a major form of preterm brain injury. Na(+)-K(+)-Cl(-) 1 cotransporter (NKCC1) expression on neurons and astrocytes is developmentally regulated and mediates Cl(-) reversal potential. We hypothesized that NKCC1 is highly expressed on oligodendrocytes (OLs) and increases vulnerability to hypoxia-ischemia (HI) mediated white matter injury, and that the NKCC1 inhibitor bumetanide would be protective in a rodent PVL model. METHODS Immunohistochemistry in Long-Evans rats and PLP-EGFP transgenic mice was used to establish cell-specific expression of NKCC1 in the immature rodent brain. HI was induced on postnatal day 6 (P6) in rats and the protective efficacy of bumetanide (0.3 mg/kg/i.p. q12h × 60 h) established. RESULTS NKCC1 was expressed on OLs and subplate neurons through the first 2 postnatal weeks, peaking in white matter and the subplate between P3-7. Following HI, NKCC1 is expressed on OLs and neurons. Bumetanide treatment significantly attenuates myelin basic protein loss and neuronal degeneration 7 d post-HI. CONCLUSION Presence and relative overexpression of NKCC1 in rodent cerebral cortex coincides with a period of developmental vulnerability to HI white matter injury in the immature prenatal brain. The protective efficacy of bumetanide in this model of preterm brain injury suggests that Cl(-) transport is a factor in PVL and that its inhibition may have clinical application in premature human infants.
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Affiliation(s)
- Lauren L Jantzie
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Melody Y Hu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Hyun-Kyung Park
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Michele C Jackson
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jenny Yu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jessie R Maxwell
- Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Frances E Jensen
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Barateiro A, Domingues HS, Fernandes A, Relvas JB, Brites D. Rat Cerebellar Slice Cultures Exposed to Bilirubin Evidence Reactive Gliosis, Excitotoxicity and Impaired Myelinogenesis that Is Prevented by AMPA and TNF-α Inhibitors. Mol Neurobiol 2013; 49:424-39. [DOI: 10.1007/s12035-013-8530-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 08/05/2013] [Indexed: 12/11/2022]
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25
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Shi Y, Yuan H, Kim D, Chanana V, Baba A, Matsuda T, Cengiz P, Ferrazzano P, Sun D. Stimulation of Na(+)/H(+) exchanger isoform 1 promotes microglial migration. PLoS One 2013; 8:e74201. [PMID: 23991215 PMCID: PMC3749130 DOI: 10.1371/journal.pone.0074201] [Citation(s) in RCA: 19] [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: 04/27/2013] [Accepted: 07/29/2013] [Indexed: 11/18/2022] Open
Abstract
Regulation of microglial migration is not well understood. In this study, we proposed that Na(+)/H(+) exchanger isoform 1 (NHE-1) is important in microglial migration. NHE-1 protein was co-localized with cytoskeletal protein ezrin in lamellipodia of microglia and maintained its more alkaline intracellular pH (pHi). Chemoattractant bradykinin (BK) stimulated microglial migration by increasing lamellipodial area and protrusion rate, but reducing lamellipodial persistence time. Interestingly, blocking NHE-1 activity with its potent inhibitor HOE 642 not only acidified microglia, abolished the BK-triggered dynamic changes of lamellipodia, but also reduced microglial motility and microchemotaxis in response to BK. In addition, NHE-1 activation resulted in intracellular Na(+) loading as well as intracellular Ca(2+) elevation mediated by stimulating reverse mode operation of Na(+)/Ca(2+) exchange (NCXrev). Taken together, our study shows that NHE-1 protein is abundantly expressed in microglial lamellipodia and maintains alkaline pHi in response to BK stimulation. In addition, NHE-1 and NCXrev play a concerted role in BK-induced microglial migration via Na(+) and Ca(2+) signaling.
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Affiliation(s)
- Yejie Shi
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Training Program, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Hui Yuan
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Dong Kim
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Vishal Chanana
- Waisman Center, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Akemichi Baba
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Toshio Matsuda
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Pelin Cengiz
- Waisman Center, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Peter Ferrazzano
- Waisman Center, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Training Program, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
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26
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Ionic transporter activity in astrocytes, microglia, and oligodendrocytes during brain ischemia. J Cereb Blood Flow Metab 2013; 33:969-82. [PMID: 23549380 PMCID: PMC3705429 DOI: 10.1038/jcbfm.2013.44] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 01/09/2023]
Abstract
Glial cells constitute a large percentage of cells in the nervous system. During recent years, a large number of studies have critically attributed to glia a new role which no longer reflects the long-held view that glia constitute solely a silent and passive supportive scaffolding for brain cells. Indeed, it has been hypothesized that glia, partnering neurons, have a much more actively participating role in brain function. Alteration of intraglial ionic homeostasis in response to ischemic injury has a crucial role in inducing and maintaining glial responses in the ischemic brain. Therefore, glial transporters as potential candidates in stroke intervention are becoming promising targets to enhance an effective and additional therapy for brain ischemia. In this review, we will describe in detail the role played by ionic transporters in influencing astrocyte, microglia, and oligodendrocyte activity and the implications that these transporters have in the progression of ischemic lesion.
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Durham-Lee JC, Mokkapati VUL, Johnson KM, Nesic O. Amiloride improves locomotor recovery after spinal cord injury. J Neurotrauma 2011; 28:1319-26. [PMID: 21534729 PMCID: PMC3136742 DOI: 10.1089/neu.2011.1921] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Amiloride is a drug approved by the United States Food and Drug Administration, which has shown neuroprotective effects in different neuropathological conditions, including brain injury or brain ischemia, but has not been tested in spinal cord injury (SCI). We tested amiloride's therapeutic potential in a clinically relevant rat model of contusion SCI inflicted at the thoracic segment T10. Rats receiving daily administration of amiloride from 24 h to 35 days after SCI exhibited a significant improvement in hindlimb locomotor ability at 21, 28, and 35 days after injury, when compared to vehicle-treated SCI rats. Rats receiving amiloride treatment also exhibited a significant increase in myelin oligodendrocyte glycoprotein (MOG) levels 35 days after SCI at the site of injury (T10) when compared to vehicle-treated controls, which indicated a partial reverse in the decrease of MOG observed with injury. Our data indicate that higher levels of MOG correlate with improved locomotor recovery after SCI, and that this may explain the beneficial effects of amiloride after SCI. Given that amiloride treatment after SCI caused a significant preservation of myelin levels, and improved locomotor recovery, it should be considered as a possible therapeutic intervention after SCI.
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Affiliation(s)
- Julieann C. Durham-Lee
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Venkata Usha L. Mokkapati
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Kathia M. Johnson
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas
| | - Olivera Nesic
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
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28
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Brustovetsky T, Brittain MK, Sheets PL, Cummins TR, Pinelis V, Brustovetsky N. KB-R7943, an inhibitor of the reverse Na+ /Ca2+ exchanger, blocks N-methyl-D-aspartate receptor and inhibits mitochondrial complex I. Br J Pharmacol 2011; 162:255-70. [PMID: 20883473 DOI: 10.1111/j.1476-5381.2010.01054.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE An isothiourea derivative (2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea methane sulfonate (KB-R7943), a widely used inhibitor of the reverse Na(+) /Ca(2+) exchanger (NCX(rev)), was instrumental in establishing the role of NCX(rev) in glutamate-induced Ca(2+) deregulation in neurons. Here, the effects of KB-R7943 on N-methyl-D-aspartate (NMDA) receptors and mitochondrial complex I were tested. EXPERIMENTAL APPROACH Fluorescence microscopy, electrophysiological patch-clamp techniques and cellular respirometry with Seahorse XF24 analyzer were used with cultured hippocampal neurons; membrane potential imaging, respirometry and Ca(2+) flux measurements were made in isolated rat brain mitochondria. KEY RESULTS KB-R7943 inhibited NCX(rev) with IC(50) = 5.7 ± 2.1 µM, blocked NMDAR-mediated ion currents, and inhibited NMDA-induced increase in cytosolic Ca(2+) with IC(50) = 13.4 ± 3.6 µM but accelerated calcium deregulation and mitochondrial depolarization in glutamate-treated neurons. KB-R7943 depolarized mitochondria in a Ca(2+) -independent manner. Stimulation of NMDA receptors caused NAD(P)H oxidation that was coupled or uncoupled from ATP synthesis depending on the presence of Ca(2+) in the bath solution. KB-R7943, or rotenone, increased NAD(P)H autofluorescence under resting conditions and suppressed NAD(P)H oxidation following glutamate application. KB-R7943 inhibited 2,4-dinitrophenol-stimulated respiration of cultured neurons with IC(50) = 11.4 ± 2.4 µM. With isolated brain mitochondria, KB-R7943 inhibited respiration, depolarized organelles and suppressed Ca(2+) uptake when mitochondria oxidized complex I substrates but was ineffective when mitochondria were supplied with succinate, a complex II substrate. CONCLUSIONS AND IMPLICATIONS KB-R7943, in addition to NCX(rev) , blocked NMDA receptors in cultured hippocampal neurons and inhibited complex I in the mitochondrial respiratory chain. These findings are critical for the correct interpretation of experimental results obtained with KB-R7943 and a better understanding of its neuroprotective action.
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Affiliation(s)
- Tatiana Brustovetsky
- Department of Pharmacology and Toxicology Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA.
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Ortuño-Sahagún D, Rivera-Cervantes MC, Gudiño-Cabrera G, Junyent F, Verdaguer E, Auladell C, Pallàs M, Camins A, Beas-Zárate C. Microarray analysis of rat hippocampus exposed to excitotoxicity: reversal Na(+)/Ca(2+) exchanger NCX3 is overexpressed in glial cells. Hippocampus 2010; 22:128-40. [PMID: 20928830 DOI: 10.1002/hipo.20869] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2010] [Indexed: 02/06/2023]
Abstract
Multiple factors are involved in the glutamate-induced excitotoxicity phenomenon, such as overload of ionotropic and metabotropic receptors, excess Ca(2+) influx, nitric oxide synthase activation, oxidative damage due to increase in free radicals, and release of endogenous polyamine, among others. In order to attempt a more integrated approach to address this issue, we established, by microarray analysis, the hippocampus gene expression profiles under glutamate-induced excitotoxicity conditions. Increased gene expression is mainly related to excitotoxicity (CaMKII, glypican 2, GFAP, NCX3, IL-2, and Gmeb2) or with cell damage response (dynactin and Ecel1). Several genes that augmented their expression are related to glutamatergic system modulation, in particular with NMDA receptor modulation and calcium homeostasis (IL-2, CaMKII, acrosin, Gmeb2, hAChE, Slc83a, and SP1 factor). Conversely, among genes that diminished their expression, we found the Syngap 1, which is downregulated by CaMKII, and the MHC II, which is downregulated by glutamate. Changes observed in gene expression induced by monosodium glutamate (MSG) neonatal treatment in the hippocampus are consistent with the activation of the mechanisms that modulate NMDA receptor function as well as with the implementation of plastic response to cell damage and intracellular calcium homeostasis. Regarding this aspect, we report here that NCX3/Slc8a3, a Na(+)/Ca(2+) membrane exchanger, is highly expressed in astrocytes, both in vitro and in vivo, in response to glutamate-induced excitotoxicity. Hence, the results of this analysis present a broad view of the expression profile elicited by MSG neonatal treatment, and lead us to suggest the possible molecular pathways of action and reaction involved under this experimental model of excitotoxicity.
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Affiliation(s)
- Daniel Ortuño-Sahagún
- Laboratorio de Desarrollo y Regeneración Neural, Instituto de Neurobiología, C.U.C.B.A, Universidad de Guadalajara, Guadalajara, Jalisco, México
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Jayakumar AR, Norenberg MD. The Na-K-Cl Co-transporter in astrocyte swelling. Metab Brain Dis 2010; 25:31-8. [PMID: 20336356 DOI: 10.1007/s11011-010-9180-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Accepted: 01/28/2010] [Indexed: 10/19/2022]
Abstract
Ion channels, exchangers and transporters are known to be involved in cell volume regulation. A disturbance in one or more of these systems may result in loss of ion homeostasis and cell swelling. In particular, activation of the Na(+)-K(+)-Cl(-) cotransporters has been shown to regulate cell volume in many conditions. The Na(+)-K(+)-Cl- cotransporters (NKCC) are a class of membrane proteins that transport Na, K, and Cl ions into and out of a wide variety of epithelial and nonepithelial cells. Studies have established the role of NKCC1 in astrocyte swelling/brain edema in ischemia and trauma. Our recent studies suggest that NKCC1 activation is also involved in astrocyte swelling induced by ammonia and in the brain edema in the thioacetamide model of acute liver failure. This review will focus on mechanisms of NKCC1 activation and its contribution to astrocyte swelling/brain edema in neurological disorders, with particular emphasis on ammonia neurotoxicity and acute liver failure.
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Affiliation(s)
- Arumugam R Jayakumar
- Department of Pathology (D-33), University of Miami Miller School of Medicine, P.O. Box 016960, Miami, FL 33125, USA.
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Chao D, Xia Y. Ionic storm in hypoxic/ischemic stress: can opioid receptors subside it? Prog Neurobiol 2009; 90:439-70. [PMID: 20036308 DOI: 10.1016/j.pneurobio.2009.12.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2009] [Revised: 09/10/2009] [Accepted: 12/17/2009] [Indexed: 12/17/2022]
Abstract
Neurons in the mammalian central nervous system are extremely vulnerable to oxygen deprivation and blood supply insufficiency. Indeed, hypoxic/ischemic stress triggers multiple pathophysiological changes in the brain, forming the basis of hypoxic/ischemic encephalopathy. One of the initial and crucial events induced by hypoxia/ischemia is the disruption of ionic homeostasis characterized by enhanced K(+) efflux and Na(+)-, Ca(2+)- and Cl(-)-influx, which causes neuronal injury or even death. Recent data from our laboratory and those of others have shown that activation of opioid receptors, particularly delta-opioid receptors (DOR), is neuroprotective against hypoxic/ischemic insult. This protective mechanism may be one of the key factors that determine neuronal survival under hypoxic/ischemic condition. An important aspect of the DOR-mediated neuroprotection is its action against hypoxic/ischemic disruption of ionic homeostasis. Specially, DOR signal inhibits Na(+) influx through the membrane and reduces the increase in intracellular Ca(2+), thus decreasing the excessive leakage of intracellular K(+). Such protection is dependent on a PKC-dependent and PKA-independent signaling pathway. Furthermore, our novel exploration shows that DOR attenuates hypoxic/ischemic disruption of ionic homeostasis through the inhibitory regulation of Na(+) channels. In this review, we will first update current information regarding the process and features of hypoxic/ischemic disruption of ionic homeostasis and then discuss the opioid-mediated regulation of ionic homeostasis, especially in hypoxic/ischemic condition, and the underlying mechanisms.
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Affiliation(s)
- Dongman Chao
- Yale University School of Medicine, Department of Pediatrics, New Haven, CT 06520, USA
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Sivakumar V, Ling EA, Lu J, Kaur C. Role of glutamate and its receptors and insulin-like growth factors in hypoxia induced periventricular white matter injury. Glia 2009; 58:507-23. [DOI: 10.1002/glia.20940] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Bakiri Y, Attwell D, Káradóttir R. Electrical signalling properties of oligodendrocyte precursor cells. NEURON GLIA BIOLOGY 2009; 5:3-11. [PMID: 19674511 DOI: 10.1017/s1740925x09990202] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Oligodendrocyte precursor cells (OPCs) have become the focus of intense research, not only because they generate myelin-forming oligodendrocytes in the normal CNS, but because they may be suitable for transplantation to treat disorders in which myelin does not form or is damaged, and because they have stem-cell-like properties in that they can generate astrocytes and neurons as well as oligodendrocytes. In this article we review the electrical signalling properties of OPCs, including the synaptic inputs they receive and their use of voltage-gated channels to generate action potentials, and we describe experiments attempting to detect output signalling from OPCs. We discuss controversy over the existence of different classes of OPC with different electrical signalling properties, and speculate on the lineage relationship and myelination potential of these different classes of OPC. Finally, we point out that, since OPCs are the main proliferating cell type in the mature brain, the discovery that they can develop into neurons raises the question of whether more neurons are generated in the mature brain from the classical sites of neurogenesis in the subventricular zone of the lateral ventricle and the hippocampal dentate gyrus or from the far more widely distributed OPCs.
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Affiliation(s)
- Yamina Bakiri
- Department of Physiology, University College London, Gower St., London, WC1E 6BT, UK
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Liu Y, Liu XJ, Sun D. Ion transporters and ischemic mitochondrial dysfunction. Cell Adh Migr 2009; 3:94-8. [PMID: 19276659 PMCID: PMC2675155 DOI: 10.4161/cam.3.1.7516] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Accepted: 12/02/2008] [Indexed: 11/19/2022] Open
Abstract
Ischemia-induced ionic imbalance leads to the activation of numerous events including mitochondrial dysfunction and eventual cell death. Dysregulation of mitochondrial Ca(2+) (Ca(2+)(m)) plays a critical role in cell damage under pathological conditions including traumatic brain injury and stroke. High Ca(2+)(m) levels can induce the persistent opening of the mitochondrial permeability transition pore and trigger mitochondrial membrane depolarization, Ca(2+) release, cessation of oxidative phosphorylation, matrix swelling and eventually outer membrane rupture with release of cytochrome c and other apoptogenic proteins. Thus, the dysregulation of mitochondrial Ca(2+) homeostasis is now recognized to play a crucial role in triggering mitochondrial dysfunction and subsequent apoptosis. Recent studies show that some secondary active transport proteins, such as Na(+)-dependent chloride transporter and Na(+)/Ca(2+) exchanger, contribute to ischemia-induced dissipation of ion homeostasis including Ca(2+)(m).
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Affiliation(s)
- Yan Liu
- Department of Neurological Surgery; University of Wisconsin School of Medicine and Public Health; Madison, WI USA
- Department of Biological Sciences and Biotechnology; Institute of Biomedical Informatics; School of Medicine; Tsinghua University; Beijing, China
| | - Xiang-jun Liu
- Department of Biological Sciences and Biotechnology; Institute of Biomedical Informatics; School of Medicine; Tsinghua University; Beijing, China
| | - Dandan Sun
- Department of Neurological Surgery; University of Wisconsin School of Medicine and Public Health; Madison, WI USA
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35
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Hertz L. Bioenergetics of cerebral ischemia: a cellular perspective. Neuropharmacology 2008; 55:289-309. [PMID: 18639906 DOI: 10.1016/j.neuropharm.2008.05.023] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Revised: 05/14/2008] [Accepted: 05/14/2008] [Indexed: 12/27/2022]
Abstract
In cerebral ischemia survival of neurons, astrocytes, oligodendrocytes and endothelial cells is threatened during energy deprivation and/or following re-supply of oxygen and glucose. After a brief summary of characteristics of different cells types, emphasizing the dependence of all on oxidative metabolism, the bioenergetics of focal and global ischemia is discussed, distinguishing between events during energy deprivation and subsequent recovery attempt after re-circulation. Gray and white matter ischemia are described separately, and distinctions are made between mature and immature brains. Next comes a description of bioenergetics in individual cell types in culture during oxygen/glucose deprivation or exposure to metabolic inhibitors and following re-establishment of normal aerated conditions. Due to their expression of NMDA and non-NMDA receptors neurons and oligodendrocytes are exquisitely sensitive to excitotoxicity by glutamate, which reaches high extracellular concentrations in ischemic brain for several reasons, including failing astrocytic uptake. Excitotoxicity kills brain cells by energetic exhaustion (due to Na(+) extrusion after channel-mediated entry) combined with mitochondrial Ca(2+)-mediated injury and formation of reactive oxygen species. Many (but not all) astrocytes survive energy deprivation for extended periods, but after return to aerated conditions they are vulnerable to mitochondrial damage by cytoplasmic/mitochondrial Ca(2+) overload and to NAD(+) deficiency. Ca(2+) overload is established by reversal of Na(+)/Ca(2+) exchangers following Na(+) accumulation during Na(+)-K(+)-Cl(-) cotransporter stimulation or pH regulation, compensating for excessive acid production. NAD(+) deficiency inhibits glycolysis and eventually oxidative metabolism, secondary to poly(ADP-ribose)polymerase (PARP) activity following DNA damage. Hyperglycemia can be beneficial for neurons but increases astrocytic death due to enhanced acidosis.
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Affiliation(s)
- Leif Hertz
- College of Basic Medical Sciences, China Medical University, Shenyang, PR China.
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Luo J, Wang Y, Chen H, Kintner DB, Cramer SW, Gerdts JK, Chen X, Shull GE, Philipson KD, Sun D. A concerted role of Na+ -K+ -Cl- cotransporter and Na+/Ca2+ exchanger in ischemic damage. J Cereb Blood Flow Metab 2008; 28:737-46. [PMID: 17912271 DOI: 10.1038/sj.jcbfm.9600561] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Na+-K+-Cl(-) cotransporter isoform 1 (NKCC1) and Na+/Ca2+ exchanger isoform 1 (NCX1) were expressed in cortical neurons. Three hours of oxygen and glucose deprivation (OGD) significantly increased expression of full-length NCX1 protein ( approximately 116 kDa), which remained elevated during 1 to 21 h reoxygenation (REOX) and was accompanied with concurrent cleavage of NCX1. Na+/Ca2+ exchanger isoform 1 heterozygous (NCX1+/-) neurons with approximately 50% less of NCX1 protein exhibited approximately 64% reduction in NCX-mediated Ca2+ influx. Expression of NCX1 and NKCC1 proteins was reduced in double heterozygous (NCX1+/-/NKCC1+/-) neurons. NCX-mediated Ca2+ influx was nearly abolished in these neurons. Three-hour OGD and 21-h REOX caused approximately 80% mortality rate in NCX1+/+ neurons and in NCX1+/- neurons. In contrast, NKCC1+/- neurons exhibited approximately 45% less cell death. The lowest mortality rate was found in NCX1+/-/NKCC1+/- neurons ( approximately 65% less neuronal death). The increased tolerance to ischemic damage was also observed in NCX1+/-/NKCC1+/- brains after transient cerebral ischemia. NCX1+/-/NKCC1+/- mice had a significantly reduced infarct volume at 24 and 72 h reperfusion. In conclusion, these data suggest that NKCC1 in conjunction with NCX1 plays a role in reperfusion-induced brain injury after ischemia.
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Affiliation(s)
- Jing Luo
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792, USA
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