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Das TK, Ganesh BP, Fatima-Shad K. Common Signaling Pathways Involved in Alzheimer's Disease and Stroke: Two Faces of the Same Coin. J Alzheimers Dis Rep 2023; 7:381-398. [PMID: 37220617 PMCID: PMC10200243 DOI: 10.3233/adr-220108] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 04/03/2023] [Indexed: 05/25/2023] Open
Abstract
Alzheimer's disease (AD) and stroke are two interrelated neurodegenerative disorders which are the leading cause of death and affect the neurons in the brain and central nervous system. Although amyloid-β aggregation, tau hyperphosphorylation, and inflammation are the hallmarks of AD, the exact cause and origin of AD are still undefined. Recent enormous fundamental discoveries suggest that the amyloid hypothesis of AD has not been proven and anti-amyloid therapies that remove amyloid deposition have not yet slowed cognitive decline. However, stroke, mainly ischemic stroke (IS), is caused by an interruption in the cerebral blood flow. Significant features of both disorders are the disruption of neuronal circuitry at different levels of cellular signaling, leading to the death of neurons and glial cells in the brain. Therefore, it is necessary to find out the common molecular mechanisms of these two diseases to understand their etiological connections. Here, we summarized the most common signaling cascades including autotoxicity, ApoE4, insulin signaling, inflammation, mTOR-autophagy, notch signaling, and microbiota-gut-brain axis, present in both AD and IS. These targeted signaling pathways reveal a better understanding of AD and IS and could provide a distinguished platform to develop improved therapeutics for these diseases.
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Affiliation(s)
- Tushar Kanti Das
- Department of Neurology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Bhanu Priya Ganesh
- Department of Neurology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Kaneez Fatima-Shad
- School of Life Sciences, University of Technology Sydney, NSW, Australia
- Ingham Institute for Applied Medical Research, Liverpool, NSW, Australia
- School of Behavioral and Health Sciences, Faculty of Health Sciences, Australian Catholic University, NSW, Australia
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2
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Kim YS, Won YJ, Lim BG, Min TJ, Kim YH, Lee IO. Neuroprotective effects of magnesium L-threonate in a hypoxic zebrafish model. BMC Neurosci 2020; 21:29. [PMID: 32590943 PMCID: PMC7318545 DOI: 10.1186/s12868-020-00580-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 06/21/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Hypoxia inhibits the uptake of glutamate (a major neurotransmitter in the brain closely related to cognitive function) into brain cells, and the initial response of cells to cortical hypoxia depends on glutamate. Previous studies have suggested that magnesium may have protective effects against hypoxic injuries. In particular, magnesium L-threonate (MgT) may increase magnesium ion concentrations in the brain better than MgSO4 and improve cognitive function. METHODS We evaluated cell viability under hypoxic conditions in the MgT- and MgSO4-treated human SH-SY5Y neurons, in vivo behavior using the T-maze test following hypoxia in MgT-treated zebrafish, activity of brain mitochondrial dehydrogenase by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and protein expression of the excitatory amino acid transporter (EAAT) 4 glutamate transporter by western blotting. RESULTS Among the groups treated with hypoxia, cell viability significantly increased when pre-treated with 1 or 10 mM MgT (p = 0.009 and 0.026, respectively). Despite hypoxic insult, MgT-treated zebrafish showed preferences for the red compartment (p = 0.025 for distance and p = 0.007 for frequency of entries), suggesting memory preservation. TTC staining showed reduced cerebral infarction and preserved absorbance in the MgT-treated zebrafish brain after hypoxia (p = 0.010 compared to the hypoxia group). In addition, western blot showed upregulation of EAAT4 protein in the MgT treated group. CONCLUSIONS Pre-treatment with MgT attenuated cell death and cerebral infarction due to hypoxia and protected cognitive function in zebrafish. In addition, MgT appeared to modulate expression of the glutamate transporter, EAAT4.
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Affiliation(s)
- Young-Sung Kim
- Department of Anesthesiology and Pain Medicine, Korea University Guro Hospital, Seoul, Korea
| | - Young Ju Won
- Department of Anesthesiology and Pain Medicine, Korea University Guro Hospital, Seoul, Korea
| | - Byung Gun Lim
- Department of Anesthesiology and Pain Medicine, Korea University Guro Hospital, Seoul, Korea
| | - Too Jae Min
- Department of Anesthesiology and Pain Medicine, Korea University Ansan Hospital, Ansan, Korea
| | - Yeon-Hwa Kim
- Institute of Medical Science, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea
| | - Il Ok Lee
- Department of Anesthesiology and Pain Medicine, Korea University Guro Hospital, Seoul, Korea.
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3
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McGuire JL, Ngwenya LB, McCullumsmith RE. Neurotransmitter changes after traumatic brain injury: an update for new treatment strategies. Mol Psychiatry 2019; 24:995-1012. [PMID: 30214042 DOI: 10.1038/s41380-018-0239-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 08/15/2018] [Accepted: 08/20/2018] [Indexed: 12/12/2022]
Abstract
Traumatic brain injury (TBI) is a pervasive problem in the United States and worldwide, as the number of diagnosed individuals is increasing yearly and there are no efficacious therapeutic interventions. A large number of patients suffer with cognitive disabilities and psychiatric conditions after TBI, especially anxiety and depression. The constellation of post-injury cognitive and behavioral symptoms suggest permanent effects of injury on neurotransmission. Guided in part by preclinical studies, clinical trials have focused on high-yield pathophysiologic mechanisms, including protein aggregation, inflammation, metabolic disruption, cell generation, physiology, and alterations in neurotransmitter signaling. Despite successful treatment of experimental TBI in animal models, clinical studies based on these findings have failed to translate to humans. The current international effort to reshape TBI research is focusing on redefining the taxonomy and characterization of TBI. In addition, as the next round of clinical trials is pending, there is a pressing need to consider what the field has learned over the past two decades of research, and how we can best capitalize on this knowledge to inform the hypotheses for future innovations. Thus, it is critically important to extend our understanding of the pathophysiology of TBI, particularly to mechanisms that are associated with recovery versus development of chronic symptoms. In this review, we focus on the pathology of neurotransmission after TBI, reflecting on what has been learned from both the preclinical and clinical studies, and we discuss new directions and opportunities for future work.
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Affiliation(s)
- Jennifer L McGuire
- Department of Neurosurgery, University of Cincinnati, Cincinnati, OH, USA.
| | - Laura B Ngwenya
- Department of Neurosurgery, University of Cincinnati, Cincinnati, OH, USA.,Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH, USA.,Neurotrauma Center, University of Cincinnati Gardner Neuroscience Institute, Cincinnati, OH, 45219, USA
| | - Robert E McCullumsmith
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA.,Department of Psychiatry, Cincinnati Veterans Administration Medical Center, Cincinnati, OH, USA
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4
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Héja L, Simon Á, Szabó Z, Kardos J. Feedback adaptation of synaptic excitability via Glu:Na + symport driven astrocytic GABA and Gln release. Neuropharmacology 2019; 161:107629. [PMID: 31103619 DOI: 10.1016/j.neuropharm.2019.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/30/2019] [Accepted: 05/07/2019] [Indexed: 02/08/2023]
Abstract
Glutamatergic transmission composed of the arriving of action potential at the axon terminal, fast vesicular Glu release, postsynaptic Glu receptor activation, astrocytic Glu clearance and Glu→Gln shuttle is an abundantly investigated phenomenon. Despite its essential role, however, much less is known about the consequences of the mechanistic connotations of Glu:Na+ symport. Due to the coupled Na+ transport, Glu uptake results in significantly elevated intracellular astrocytic [Na+] that markedly alters the driving force of other Na+-coupled astrocytic transporters. The resulting GABA and Gln release by reverse transport through the respective GAT-3 and SNAT3 transporters help to re-establish the physiological Na+ homeostasis without ATP dissipation and consequently leads to enhanced tonic inhibition and replenishment of axonal glutamate pool. Here, we place this emerging astrocytic adjustment of synaptic excitability into the centre of future perspectives. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Ágnes Simon
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Zsolt Szabó
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary.
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5
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O'Neil DA, Nicholas MA, Lajud N, Kline AE, Bondi CO. Preclinical Models of Traumatic Brain Injury: Emerging Role of Glutamate in the Pathophysiology of Depression. Front Pharmacol 2018; 9:579. [PMID: 29910733 PMCID: PMC5992468 DOI: 10.3389/fphar.2018.00579] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/15/2018] [Indexed: 12/19/2022] Open
Abstract
More than 10 million people worldwide incur a traumatic brain injury (TBI) each year, with two million cases occurring in the United States. TBI survivors exhibit long-lasting cognitive and affective sequelae that are associated with reduced quality of life and work productivity, as well as mental and emotional disturbances. While TBI-related disabilities often manifest physically and conspicuously, TBI has been linked with a "silent epidemic" of psychological disorders, including major depressive disorder (MDD). The prevalence of MDD post-insult is approximately 50% within the 1st year. Furthermore, given they are often under-reported when mild, TBIs could be a significant overall cause of MDD in the United States. The emergence of MDD post-TBI may be rooted in widespread disturbances in the modulatory role of glutamate, such that glutamatergic signaling becomes excessive and deleterious to neuronal integrity, as reported in both clinical and preclinical studies. Following this acute glutamatergic storm, regulators of glutamatergic function undergo various manipulations, which include, but are not limited to, alterations in glutamatergic subunit composition, release, and reuptake. This review will characterize the glutamatergic functional and signaling changes that emerge and persist following experimental TBI, utilizing evidence from clinical, molecular, and rodent behavioral investigations. Special care will be taken to speculate on how these manipulations may correlate with the development of MDD following injury in the clinic, as well as pharmacotherapies to date. Indisputably, TBI is a significant healthcare issue that warrants discovery and subsequent refinement of therapeutic strategies to improve neurobehavioral recovery and mental health.
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Affiliation(s)
- Darik A O'Neil
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, United States
| | - Melissa A Nicholas
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, United States
| | - Naima Lajud
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, United States.,División de Neurociencias, Centro de Investigación Biomédica de Michoacán - Instituto Mexicano del Seguro Social, Morelia, Mexico
| | - Anthony E Kline
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States.,Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Psychology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Corina O Bondi
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, United States.,Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States
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6
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Garcia IJP, Kinoshita PF, Braga I, Parreira GM, Mignaco JA, Scavone C, Barbosa LA, Santos H. Ouabain attenuates the oxidative stress induced by lipopolysaccharides in the cerebellum of rats. J Cell Biochem 2017; 119:2156-2167. [DOI: 10.1002/jcb.26377] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 08/24/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Israel José Pereira Garcia
- Laboratório de Bioquímica Celular, Universidade Federal de São João del ReiCampus Centro‐Oeste Dona LinduDivinópolisMGBrazil
| | - Paula Fernanda Kinoshita
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical ScienceUniversity of São PauloSão PauloBrazil
| | - Italo Braga
- Laboratório de Bioquímica Celular, Universidade Federal de São João del ReiCampus Centro‐Oeste Dona LinduDivinópolisMGBrazil
| | - Gabriela Machado Parreira
- Laboratório de Bioquímica Celular, Universidade Federal de São João del ReiCampus Centro‐Oeste Dona LinduDivinópolisMGBrazil
| | - Julio Alberto Mignaco
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da SaúdeUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
| | - Cristoforo Scavone
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical ScienceUniversity of São PauloSão PauloBrazil
| | - Leandro Augusto Barbosa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del ReiCampus Centro‐Oeste Dona LinduDivinópolisMGBrazil
| | - Hérica Santos
- Laboratório de Bioquímica Celular, Universidade Federal de São João del ReiCampus Centro‐Oeste Dona LinduDivinópolisMGBrazil
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7
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Dorsett CR, McGuire JL, DePasquale EAK, Gardner AE, Floyd CL, McCullumsmith RE. Glutamate Neurotransmission in Rodent Models of Traumatic Brain Injury. J Neurotrauma 2016; 34:263-272. [PMID: 27256113 DOI: 10.1089/neu.2015.4373] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Traumatic brain injury (TBI) is a leading cause of death and disability in people younger than 45 and is a significant public health concern. In addition to primary mechanical damage to cells and tissue, TBI involves additional molecular mechanisms of injury, termed secondary injury, that continue to evolve over hours, days, weeks, and beyond. The trajectory of recovery after TBI is highly unpredictable and in many cases results in chronic cognitive and behavioral changes. Acutely after TBI, there is an unregulated release of glutamate that cannot be buffered or cleared effectively, resulting in damaging levels of glutamate in the extracellular space. This initial loss of glutamate homeostasis may initiate additional changes in glutamate regulation. The excitatory amino acid transporters (EAATs) are expressed on both neurons and glia and are the principal mechanism for maintaining extracellular glutamate levels. Diffusion of glutamate outside the synapse due to impaired uptake may lead to increased extrasynaptic glutamate signaling, secondary injury through activation of cell death pathways, and loss of fidelity and specificity of synaptic transmission. Coordination of glutamate release and uptake is critical to regulating synaptic strength, long-term potentiation and depression, and cognitive processes. In this review, we will discuss dysregulation of extracellular glutamate and glutamate uptake in the acute stage of TBI and how failure to resolve acute disruptions in glutamate homeostatic mechanisms may play a causal role in chronic cognitive symptoms after TBI.
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Affiliation(s)
- Christopher R Dorsett
- 1 Biological and Biomedical Sciences Doctoral Program, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Jennifer L McGuire
- 2 Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati , Cincinnati, Ohio
| | - Erica A K DePasquale
- 2 Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati , Cincinnati, Ohio
| | - Amanda E Gardner
- 2 Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati , Cincinnati, Ohio
| | - Candace L Floyd
- 3 Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham , Birmingham, Alabama
| | - Robert E McCullumsmith
- 2 Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati , Cincinnati, Ohio
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8
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Ritter AC, Kammerer CM, Brooks MM, Conley YP, Wagner AK. Genetic variation in neuronal glutamate transport genes and associations with posttraumatic seizure. Epilepsia 2016; 57:984-93. [PMID: 27153812 PMCID: PMC4903934 DOI: 10.1111/epi.13397] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2016] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Posttraumatic seizures (PTS) commonly occur following severe traumatic brain injury (sTBI). Risk factors for PTS have been identified, but variability in who develops PTS remains. Excitotoxicity may influence epileptogenesis following sTBI. Glutamate transporters manage glutamate levels and excitatory neurotransmission, and they have been associated with both epilepsy and TBI. Therefore, we aimed to determine if genetic variation in neuronal glutamate transporter genes is associated with accelerated epileptogenesis and increased PTS risk after sTBI. METHODS Individuals (N = 253) 18-75 years of age with sTBI were assessed for genetic relationships with PTS. Single nucleotide polymorphisms (SNPs) within SLC1A1 and SLC1A6 were assayed. Kaplan-Meier estimates and log-rank statistics were used to compare seizure rates from injury to 3 years postinjury for SNPs by genotype. Hazard ratios (HRs) were estimated using Cox proportional hazards regression for SNPs significant in Kaplan-Meier analyses adjusting for known PTS risk factors. RESULTS Thirty-two tagging SNPs were examined (SLC1A1: n = 28, SLC1A6: n = 4). Forty-nine subjects (19.37%) had PTS. Of these, 18 (36.7%) seized within 7 days, and 31 (63.3%) seized between 8 days and 3 years post-TBI. With correction for multiple comparisons, genotypes at SNP rs10974620 (SLC1A1) were significantly associated with time to first seizure across the full 3-year follow-up (seizure rates: 77.1% minor allele homozygotes, 24.8% heterozygotes, 16.6% major allele homozygotes; p = 0.001). When seizure follow-up began day 2 postinjury, genotypes at SNP rs7858819 (SLC1A1) were significantly associated with PTS risk (seizure rates: 52.7% minor allele homozygotes, 11.8% heterozygotes, 21.1% major allele homozygotes; p = 0.002). After adjusting for covariates, we found that rs10974620 remained significant (p = 0.017, minor allele versus major allele homozygotes HR 3.4, 95% confidence interval [CI] 1.3-9.3). rs7858819 also remained significant in adjusted models (p = 0.023, minor allele versus major allele homozygotes HR 3.4, 95%CI 1.1-10.5). SIGNIFICANCE Variations within SLC1A1 are associated with risk of epileptogenesis following sTBI. Future studies need to confirm findings, but variation within neuronal glutamate transporter genes may represent a possible pharmaceutical target for PTS prevention and treatment.
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Affiliation(s)
- Anne C Ritter
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA
| | | | - Maria M Brooks
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA
| | - Yvette P Conley
- Department of Health Promotion and Human Genetics, University of Pittsburgh, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
| | - Amy K Wagner
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA
- Center for Neuroscience at University of Pittsburgh, Pittsburgh, PA
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9
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Kraitsy K, Uecal M, Grossauer S, Bruckmann L, Pfleger F, Ropele S, Fazekas F, Gruenbacher G, Patz S, Absenger M, Porubsky C, Smolle-Juettner F, Tezer I, Molcanyi M, Fasching U, Schaefer U. Repetitive long-term hyperbaric oxygen treatment (HBOT) administered after experimental traumatic brain injury in rats induces significant remyelination and a recovery of sensorimotor function. PLoS One 2014; 9:e97750. [PMID: 24848795 PMCID: PMC4029808 DOI: 10.1371/journal.pone.0097750] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 04/24/2014] [Indexed: 12/20/2022] Open
Abstract
Cells in the central nervous system rely almost exclusively on aerobic metabolism. Oxygen deprivation, such as injury-associated ischemia, results in detrimental apoptotic and necrotic cell loss. There is evidence that repetitive hyperbaric oxygen therapy (HBOT) improves outcomes in traumatic brain-injured patients. However, there are no experimental studies investigating the mechanism of repetitive long-term HBOT treatment-associated protective effects. We have therefore analysed the effect of long-term repetitive HBOT treatment on brain trauma-associated cerebral modulations using the lateral fluid percussion model for rats. Trauma-associated neurological impairment regressed significantly in the group of HBO-treated animals within three weeks post trauma. Evaluation of somatosensory-evoked potentials indicated a possible remyelination of neurons in the injured hemisphere following HBOT. This presumption was confirmed by a pronounced increase in myelin basic protein isoforms, PLP expression as well as an increase in myelin following three weeks of repetitive HBO treatment. Our results indicate that protective long-term HBOT effects following brain injury is mediated by a pronounced remyelination in the ipsilateral injured cortex as substantiated by the associated recovery of sensorimotor function.
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Affiliation(s)
- Klaus Kraitsy
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Muammer Uecal
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Stefan Grossauer
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Lukas Bruckmann
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Florentina Pfleger
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Stefan Ropele
- Clinical Division of General Neurology, Medical University of Graz, Graz, Austria
| | - Franz Fazekas
- Clinical Division of General Neurology, Medical University of Graz, Graz, Austria
| | - Gerda Gruenbacher
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Silke Patz
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Markus Absenger
- Core Facility Microscopy, Centre for Medical Research, Medical University of Graz, Graz, Austria
| | - Christian Porubsky
- Division of Thoracic and Hyperbaric Surgery, Department of Surgery, Medical University of Graz, Graz, Austria
| | - Freyja Smolle-Juettner
- Division of Thoracic and Hyperbaric Surgery, Department of Surgery, Medical University of Graz, Graz, Austria
| | - Irem Tezer
- Division of Thoracic and Hyperbaric Surgery, Department of Surgery, Medical University of Graz, Graz, Austria
| | - Marek Molcanyi
- Department of Neurosurgery, University of Cologne, Cologne, Germany
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Ulrike Fasching
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
| | - Ute Schaefer
- Research Unit for Experimental Neurotraumatology, Medical University of Graz, Graz, Austria
- * E-mail:
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10
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de Vivo L, Melone M, Bucci G, Rothstein JD, Conti F. Quantitative analysis of EAAT4 promoter activity in neurons and astrocytes of mouse somatic sensory cortex. Neurosci Lett 2010; 474:42-5. [PMID: 20211693 DOI: 10.1016/j.neulet.2010.03.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 02/22/2010] [Accepted: 03/01/2010] [Indexed: 10/19/2022]
Abstract
EAAT4-eGFP BAC reporter transgenic adult mice were used to detect EAAT4 gene expression in individual cells of cerebral cortex, and eGFP fluorescence was measured to compare EAAT4 promoter activity in different cells. Most eGFP+ cells were neurons; only rare GFAP+ profiles were eGFP+. About 10% of NeuN+ cells was eGFP+, and the percentage of NeuN/eGFP co-localization varied from 2 to 20% of NeuN+ cells throughout cortical layers: layers I and II-III showed the highest values of co-localization, layer IV the lowest. The intensity of eGFP fluorescence did not exhibit laminar variations. Finally, we observed that EAAT4 promoter activity in cortical neurons was 10% of that measured in cerebellar Purkinje cells, i.e., the cells displaying the highest intensity in the CNS. These results extend our knowledge on EAAT4 expression in the cerebral cortex of adult mice, and suggest that the role of EAAT4 in cortical glutamatergic transmission may be more important than previously thought.
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Affiliation(s)
- Luisa de Vivo
- Dipartimento di Neuroscienze, Università Politecnica delle Marche, Ancona, Italy
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11
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Massie A, Cnops L, Smolders I, McCullumsmith R, Kooijman R, Kwak S, Arckens L, Michotte Y. High-affinity Na+/K+-dependent glutamate transporter EAAT4 is expressed throughout the rat fore- and midbrain. J Comp Neurol 2008; 511:155-72. [DOI: 10.1002/cne.21823] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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