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Revuelta M, Elicegui A, Scheuer T, Endesfelder S, Bührer C, Moreno-Cugnon L, Matheu A, Schmitz T. In vitro P38MAPK inhibition in aged astrocytes decreases reactive astrocytes, inflammation and increases nutritive capacity after oxygen-glucose deprivation. Aging (Albany NY) 2021; 13:6346-6358. [PMID: 33563843 PMCID: PMC7993689 DOI: 10.18632/aging.202651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 12/18/2020] [Indexed: 01/02/2023]
Abstract
Proper astroglial functioning is essential for the development and survival of neurons and oligodendroglia under physiologic and pathological circumstances. Indeed, malfunctioning of astrocytes represents an important factor contributing to brain injury. However, the molecular pathways of this astroglial dysfunction are poorly defined. In this work we show that aging itself can drastically perturb astrocyte viability with an increase of inflammation, cell death and astrogliosis. Moreover, we demonstrate that oxygen glucose deprivation (OGD) has a higher impact on nutritive loss in aged astrocytes compared to young ones, whereas aged astrocytes have a higher activity of the anti-oxidant systems. P38MAPK signaling has been identified to be upregulated in neurons, astrocytes and microglia after ischemic stroke. By using a pharmacological p38α specific inhibitor (PH-797804), we show that p38MAPK pathway has an important role in aged astrocytes for inflammatory and oxidative stress responses with the subsequent cell death that occurs after OGD.
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Affiliation(s)
- Miren Revuelta
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
- Cellular Oncology Group, Biodonostia Health Research Institute, Paseo Doctor Begiristain, San Sebastian 20014, Spain
| | - Amaia Elicegui
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
- Neurovascular Research Laboratory, Vall d’Hebron Institute of Research, Barcelona 08035, Spain
| | - Till Scheuer
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
| | - Stefanie Endesfelder
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
| | - Christoph Bührer
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
| | - Leire Moreno-Cugnon
- Cellular Oncology Group, Biodonostia Health Research Institute, Paseo Doctor Begiristain, San Sebastian 20014, Spain
| | - Ander Matheu
- Cellular Oncology Group, Biodonostia Health Research Institute, Paseo Doctor Begiristain, San Sebastian 20014, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao 48013, Spain
- CIBERfes, Madrid 28029, Spain
| | - Thomas Schmitz
- Department for Neonatology, Charité University Medical Center, Berlin 13353, Germany
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2
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Gerace E, Ilari A, Caffino L, Buonvicino D, Lana D, Ugolini F, Resta F, Nosi D, Grazia Giovannini M, Ciccocioppo R, Fumagalli F, Pellegrini-Giampietro DE, Masi A, Mannaioni G. Ethanol neurotoxicity is mediated by changes in expression, surface localization and functional properties of glutamate AMPA receptors. J Neurochem 2020; 157:2106-2118. [PMID: 33107046 DOI: 10.1111/jnc.15223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 10/13/2020] [Accepted: 10/19/2020] [Indexed: 11/28/2022]
Abstract
Modifications in the subunit composition of AMPA receptors (AMPARs) have been linked to the transition from physiological to pathological conditions in a number of contexts, including EtOH-induced neurotoxicity. Previous work from our laboratory showed that EtOH withdrawal causes CA1 pyramidal cell death in organotypic hippocampal slices and changes in the expression of AMPARs. Here, we investigated whether changes in expression and function of AMPARs may be causal for EtOH-induced neurotoxicity. To this aim, we examined the subunit composition, localization and function of AMPARs in hippocampal slices exposed to EtOH by using western blotting, surface expression assay, confocal microscopy and electrophysiology. We found that EtOH withdrawal specifically increases GluA1 protein signal in total homogenates, but not in the post-synaptic density-enriched fraction. This is suggestive of overall increase and redistribution of AMPARs to the extrasynaptic compartment. At functional level, AMPA-induced calcium influx was unexpectedly reduced, whereas AMPA-induced current was enhanced in CA1 pyramidal neurons following EtOH withdrawal, suggesting that increased AMPAR expression may lead to cell death because of elevated excitability, and not for a direct contribution on calcium influx. Finally, the neurotoxicity caused by EtOH withdrawal was attenuated by the non-selective AMPAR antagonist 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide disodium salt as well as by the selective antagonist of GluA2-lacking AMPARs 1-naphthyl acetyl spermine. We conclude that EtOH neurotoxicity involves changes in expression, surface localization and functional properties of AMPARs, and propose GluA2-lacking AMPARs as amenable specific targets for the development of neuroprotective drugs in EtOH-withdrawal syndrome.
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Affiliation(s)
- Elisabetta Gerace
- Department of Neuroscience, Psychology, Drug Research and Child Health (NeuroFarBa), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Alice Ilari
- Department of Neuroscience, Psychology, Drug Research and Child Health (NeuroFarBa), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy.,School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, Italy
| | - Lucia Caffino
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Daniela Buonvicino
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Daniele Lana
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Filippo Ugolini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Francesco Resta
- European Laboratory for Non-Linear Spectroscopy, Sesto Fiorentino, Italy.,Department of Physics and Astronomy, University of Florence, Florence, Italy
| | - Daniele Nosi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Maria Grazia Giovannini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - Roberto Ciccocioppo
- School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, Italy
| | - Fabio Fumagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | | | - Alessio Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NeuroFarBa), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Guido Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health (NeuroFarBa), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
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3
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Nagy EE, Frigy A, Szász JA, Horváth E. Neuroinflammation and microglia/macrophage phenotype modulate the molecular background of post-stroke depression: A literature review. Exp Ther Med 2020; 20:2510-2523. [PMID: 32765743 PMCID: PMC7401670 DOI: 10.3892/etm.2020.8933] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/05/2020] [Indexed: 12/16/2022] Open
Abstract
Increasing evidence hints to the central role of neuroinflammation in the development of post-stroke depression. Danger signals released in the acute phase of ischemia trigger microglial activation, along with the infiltration of neutrophils and macrophages. The increased secretion of proinflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor α (TNFα) provokes neuronal degeneration and apoptosis, whereas IL-6, interferon γ (IFNγ), and TNFα induce aberrant tryptophane degradation with the accumulation of the end-product quinolinic acid in resident glial cells. This promotes glutamate excitotoxicity via hyperexcitation of N-methyl-D-aspartate receptors and antagonizes 5-hydroxy-tryptamine, reducing synaptic plasticity and neuronal survival, thus favoring depression. In the post-stroke period, CX3CL1 and the CD200-CD200R interaction mediates the activation of glial cells, whereas CCL-2 attracts infiltrating macrophages. CD206 positive cells grant the removal of excessive danger signals; the high number of regulatory T cells, IL-4, IL-10, transforming growth factor β (TGFβ), and intracellular signaling via cAMP response element-binding protein (CREB) support the M2 type differentiation. In favorable conditions, these cells may exert efficient clearance, mediate tissue repair, and might be essential players in the downregulation of molecular pathways that promote post-stroke depression.
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Affiliation(s)
- Előd Ernő Nagy
- Department of Biochemistry and Environmental Chemistry, 'George Emil Palade' University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540139 Targu Mures, Romania
| | - Attila Frigy
- Department of Internal Medicine IV, 'George Emil Palade' University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540103 Targu Mures, Romania
| | - József Attila Szász
- Neurology Clinic II, 'George Emil Palade' University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540136 Targu Mures, Romania
| | - Emőke Horváth
- Department of Pathology, 'George Emil Palade' University of Medicine, Pharmacy, Science and Technology of Targu Mures, 540139 Targu Mures, Romania
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Cavallo D, Landucci E, Gerace E, Lana D, Ugolini F, Henley JM, Giovannini MG, Pellegrini-Giampietro DE. Neuroprotective effects of mGluR5 activation through the PI3K/Akt pathway and the molecular switch of AMPA receptors. Neuropharmacology 2020; 162:107810. [PMID: 31600563 DOI: 10.1016/j.neuropharm.2019.107810] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/23/2019] [Accepted: 10/03/2019] [Indexed: 12/19/2022]
Abstract
Previous studies have demonstrated that antagonists of mGluR1, but not mGluR5, are neuroprotective in models of cerebral ischemia. To investigate the individual roles of mGlu1 and mGlu5 receptors in in vitro model of cerebral ischemia we used low doses of the non-selective group I agonist DHPG and mGlu1 and mGlu5 selective positive allosteric modulators (PAMs). In hippocampal slices subjected to 30 min oxygen-glucose deprivation (OGD), DHPG (1 μM) and the mGluR5 PAM (VU0092273) significantly reduced OGD-induced CA1 injury monitored by propidium iodide staining of the slices and quantitative analysis of CA1 neurons. In contrast, the mGluR1 PAM (VU0483605) showed no neuroprotection. These protective effects of DHPG and VU0092273 were prevented by inhibition of PI3K/Akt pathway by LY294002. The mGluR5 PAM (VU0092273) also prevented GluA2 down-regulation triggered by ischemic injury, via PI3K/Akt pathway, revealing a further contribution to its neuroprotective effects by reducing the excitotoxic effects of increased Ca2+ influx through GluA2-lacking AMPA receptors. Furthermore, immunohistochemical assays confirmed the neuroprotective effect of VU0092273 and revealed activation of glia, indicating the involvement reactive astrogliosis in the mechanisms of neuroprotection. Our data suggest that selective activation/potentiation of mGluR5 signalling represents a promising strategy for the development of new interventions to reduce or prevent ischemia-induced neuronal death.
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Affiliation(s)
- Damiana Cavallo
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy; School of Biochemistry, Centre for Synaptic Plasticity, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK.
| | - Elisa Landucci
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Elisabetta Gerace
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Daniele Lana
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Filippo Ugolini
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Jeremy M Henley
- School of Biochemistry, Centre for Synaptic Plasticity, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Maria Grazia Giovannini
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
| | - Domenico E Pellegrini-Giampietro
- Department of Health Sciences, Unit of Clinical Pharmacology and Oncology, University of Florence, Viale G. Pieraccini 6, 50139, Florence, Italy
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Malik AR, Willnow TE. Excitatory Amino Acid Transporters in Physiology and Disorders of the Central Nervous System. Int J Mol Sci 2019; 20:ijms20225671. [PMID: 31726793 PMCID: PMC6888459 DOI: 10.3390/ijms20225671] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/07/2019] [Accepted: 11/11/2019] [Indexed: 12/12/2022] Open
Abstract
Excitatory amino acid transporters (EAATs) encompass a class of five transporters with distinct expression in neurons and glia of the central nervous system (CNS). EAATs are mainly recognized for their role in uptake of the amino acid glutamate, the major excitatory neurotransmitter. EAATs-mediated clearance of glutamate released by neurons is vital to maintain proper glutamatergic signalling and to prevent toxic accumulation of this amino acid in the extracellular space. In addition, some EAATs also act as chloride channels or mediate the uptake of cysteine, required to produce the reactive oxygen speciesscavenger glutathione. Given their central role in glutamate homeostasis in the brain, as well as their additional activities, it comes as no surprise that EAAT dysfunctions have been implicated in numerous acute or chronic diseases of the CNS, including ischemic stroke and epilepsy, cerebellar ataxias, amyotrophic lateral sclerosis, Alzheimer’s disease and Huntington’s disease. Here we review the studies in cellular and animal models, as well as in humans that highlight the roles of EAATs in the pathogenesis of these devastating disorders. We also discuss the mechanisms regulating EAATs expression and intracellular trafficking and new exciting possibilities to modulate EAATs and to provide neuroprotection in course of pathologies affecting the CNS.
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Affiliation(s)
- Anna R. Malik
- Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
- Correspondence:
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6
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Landucci E, Llorente IL, Anuncibay-Soto B, Pellegrini-Giampietro DE, Fernández-López A. Using organotypic hippocampal slice cultures to gain insight into mechanisms responsible for the neuroprotective effects of meloxicam: a role for gamma aminobutyric and endoplasmic reticulum stress. Neural Regen Res 2018; 14:65-66. [PMID: 30531073 PMCID: PMC6263004 DOI: 10.4103/1673-5374.243704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Elisa Landucci
- Sezione di Farmacologia Clinica e Oncologia, Dipartimento di Scienze della Salute, Università di Firenze, Firenze, Italy
| | - Irene L Llorente
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Berta Anuncibay-Soto
- Área de Biología Celular, Instituto de Biomedicina, Universidad de León; Neural Therapies SL, Edificio Institutos de Investigación, León, Spain
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7
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Landucci E, Llorente IL, Anuncibay-Soto B, Pellegrini-Giampietro DE, Fernández-López A. Bicuculline Reverts the Neuroprotective Effects of Meloxicam in an Oxygen and Glucose Deprivation (OGD) Model of Organotypic Hippocampal Slice Cultures. Neuroscience 2018; 386:68-78. [PMID: 29949743 DOI: 10.1016/j.neuroscience.2018.06.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 05/25/2018] [Accepted: 06/18/2018] [Indexed: 01/17/2023]
Abstract
We previously demonstrated that the non-steroidal anti-inflammatory agent meloxicam has neuroprotective effects in an oxygen and glucose deprivation model (OGD) of rat organotypic hippocampal slice cultures. We wondered if GABAergic transmission changed the neuroprotective effects of meloxicam and if meloxicam was able to modulate endoplasmic reticulum stress (ER stress) in this model. Mortality was measured using propidium iodide. Western blot assays were performed to measure levels of cleaved and non-cleaved caspase-3 to quantify apoptosis, while levels of GRP78, GRP94 and phosphorylated eIF2α were used to detect unfolded protein response (UPR). Transcript levels of GRP78, GRP94 and GABAergic receptor α, β, and γ subunits were measured by real-time quantitative polymerase chain reaction (qPCR). In the present study, we show that the presence of meloxicam in a 30 min OGD assay, followed by 24 h of normoxic conditions, presented an antiapoptotic effect. The simultaneous presence of the GABAA receptor antagonist, bicuculline, in combination with meloxicam blocked the neuroprotective effect provided by the latter. However, in light of its effects on caspase 3 and PARP, bicuculline did not seem to promote the apoptotic pathway. Our results also showed that meloxicam modified the unfolded protein response (UPR), as well as the transcriptional response of different genes, including the GABAA receptor, alpha1, beta3 and gamma2 subunits. We concluded that meloxicam has a neuroprotective anti-apoptotic action, is able to enhance the UPR independently of the systemic anti-inflammatory response and its neuroprotective effect can be inhibited by blocking GABAA receptors.
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Affiliation(s)
- Elisa Landucci
- Sezione di Farmacologia Clinica e Oncologia, Dipartimento di Scienze della Salute, Università di Firenze, Viale Pieraccini 6, 50139 Firenze, Italy.
| | - Irene L Llorente
- Neurology Department, David Geffen School of Medicine, University of California, Los Angeles, USA.
| | - Berta Anuncibay-Soto
- Área de Biología Celular, Instituto de Biomedicina, Universidad de León, 24071 León, Spain; Neural Therapies SL, Edificio Institutos de Investigación, Local B14, Universidad de León, 24071 León, Spain.
| | - Domenico E Pellegrini-Giampietro
- Sezione di Farmacologia Clinica e Oncologia, Dipartimento di Scienze della Salute, Università di Firenze, Viale Pieraccini 6, 50139 Firenze, Italy.
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8
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Anuncibay-Soto B, Pérez-Rodriguez D, Santos-Galdiano M, Font-Belmonte E, Ugidos IF, Gonzalez-Rodriguez P, Regueiro-Purriños M, Fernández-López A. Salubrinal and robenacoxib treatment after global cerebral ischemia. Exploring the interactions between ER stress and inflammation. Biochem Pharmacol 2018; 151:26-37. [PMID: 29499167 DOI: 10.1016/j.bcp.2018.02.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/23/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND Blood reperfusion of the ischemic tissue after stroke promotes increases in the inflammatory response as well as accumulation of unfolded/misfolded proteins in the cell, leading to endoplasmic reticulum (ER) stress. Both Inflammation and ER stress are critical processes in the delayed death of the cells damaged after ischemia. The aim of this study is to check the putative synergic neuroprotective effect by combining anti-inflammatory and anti-ER stress agents after ischemia. METHODS The study was performed on a two-vessel occlusion global cerebral ischemia model. Animals were treated with salubrinal one hour after ischemia and with robenacoxib at 8 h and 32 h after ischemia. Parameters related to the integrity of the blood-brain barrier (BBB), such as matrix metalloproteinase 9 and different cell adhesion molecules (CAMs), were analyzed by qPCR at 24 h and 48 h after ischemia. Microglia and cell components of the neurovascular unit, including neurons, endothelial cells and astrocytes, were analyzed by immunofluorescence after 48 h and seven days of reperfusion. RESULTS Pharmacologic control of ER stress by salubrinal treatment after ischemia, revealed a neuroprotective effect over neurons that reduces the transcription of molecules involved in the impairment of the BBB. Robenacoxib treatment stepped neuronal demise forward, revealing a detrimental effect of this anti-inflammatory agent. Combined treatment with robenacoxib and salubrinal after ischemia prevented neuronal loss and changes in components of the neurovascular unit and microglia observed when animals were treated only with robenacoxib. CONCLUSION Combined treatment with anti-ER stress and anti-inflammatory agents is able to provide enhanced neuroprotective effects reducing glial activation, which opens new avenues in therapies against stroke.
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Affiliation(s)
| | | | | | | | - Irene F Ugidos
- Dpt. Biología Celular, Instituto Biomedicina. Universidad de León, Spain
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Liu JJ, Ding XY, Xiang L, Zhao F, Huang SL. A novel method for oxygen glucose deprivation model in organotypic spinal cord slices. Brain Res Bull 2017; 135:163-169. [DOI: 10.1016/j.brainresbull.2017.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 12/20/2022]
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Effects of Gualou Guizhi Decoction Aqueous Extract on Axonal Regeneration in Organotypic Cortical Slice Culture after Oxygen-Glucose Deprivation. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:5170538. [PMID: 29075304 PMCID: PMC5624132 DOI: 10.1155/2017/5170538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/28/2017] [Accepted: 08/16/2017] [Indexed: 11/18/2022]
Abstract
Gualou Guizhi decoction (GLGZD) is effective for the clinical treatment of limb spasms caused by ischemic stroke, but its underlying mechanism is unclear. Propidium iodide (PI) fluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), immunohistochemistry, western blot, and real-time qPCR were used to observe the axonal regeneration and neuroprotective effects of GLGZD aqueous extract on organotypic cortical slices exposed to oxygen-glucose deprivation (OGD) and further elucidate the potential mechanisms. Compared with the OGD group, the GLGZD aqueous extract decreased the red PI fluorescence intensity; inhibited neuronal apoptosis; improved the growth of slice axons; upregulated the protein expression of tau and growth-associated protein-43; and decreased protein and mRNA expression of neurite outgrowth inhibitor protein-A (Nogo-A), Nogo receptor 1 (NgR1), ras homolog gene family A (RhoA), rho-associated coiled-coil-containing protein kinase (ROCK), and phosphorylation of collapsin response mediator protein 2 (CRMP2). Our study found that GLGZD had a strong neuroprotective effect on brain slices after OGD injury. GLGZD plays a vital role in promoting axonal remodeling and functional remodeling, which may be related to regulation of the expression of Nogo-A and its receptor NgR1, near the injured axons, inhibition of the Rho-ROCK pathway, and reduction of CRMP2 phosphorylation.
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Zelena D, Mikics É, Balázsfi D, Varga J, Klausz B, Urbán E, Sipos E, Biró L, Miskolczi C, Kovács K, Ferenczi S, Haller J. Enduring abolishment of remote but not recent expression of conditioned fear by the blockade of calcium-permeable AMPA receptors before extinction training. Psychopharmacology (Berl) 2016; 233:2065-2076. [PMID: 27020785 DOI: 10.1007/s00213-016-4255-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 02/21/2016] [Indexed: 11/29/2022]
Abstract
RATIONALE Calcium-permeable (GluA2 subunit-free) AMPA receptors (CP-AMPAR) play prominent roles in fear extinction; however, no blockers of these receptors were studied in tests relevant to extinction learning so far. METHODS The CP-AMPAR antagonist IEM-1460 was administered once before extinction trainings, which were started either 1 or 28 days after fear conditioning (FC). We used a mild extinction protocol that durably decreased but did not abolish conditioned fear. The messenger RNA (mRNA) expression of GluA1 and GluA2 subunits were investigated at both time points in the ventromedial prefrontal cortex (vmPFC) and amygdala. RESULTS IEM-1460 transiently facilitated extinction 1 day after conditioning, but learned fear spontaneously recovered 4 weeks later. When the extinction protocol was applied 28 days after training, IEM-1460 enhanced extinction memory, moreover abolished conditioned fear for at least a month. The expression of GluA1 and GluA2 mRNAs was increased at both time points in the vmPFC. In the basolateral and central amygdala, the GluA1/GluA2 mRNA ratio increased, suggesting a shift towards the preponderance of GluA1 over GluA2 expression. CONCLUSIONS AMPAR blockade lastingly enhanced the extinction of remote but not recent fear memories. Time-dependent changes in AMPA receptor subunit mRNA expression may explain the differential effects of CP-AMPAR blockade on recent and remote conditioned fear, further supporting the notion that the mechanisms maintaining learned fear change over time. Our findings suggest clinical implications for CP-AMPAR blockers, particularly for acquired anxieties (e.g., post-traumatic stress disorder) which have a slow onset and are durable.
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Affiliation(s)
- Dóra Zelena
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary.
| | - Éva Mikics
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Diána Balázsfi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - János Varga
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Barbara Klausz
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Eszter Urbán
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Eszter Sipos
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - László Biró
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Christina Miskolczi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Krisztina Kovács
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - Szilamér Ferenczi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
| | - József Haller
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1083, Budapest, Szigony 43, Hungary
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