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Tescarollo FC, Valdivia D, Chen S, Sun H. Unilateral optogenetic kindling of hippocampus leads to more severe impairments of the inhibitory signaling in the contralateral hippocampus. Front Mol Neurosci 2023; 16:1268311. [PMID: 37942301 PMCID: PMC10627882 DOI: 10.3389/fnmol.2023.1268311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/20/2023] [Indexed: 11/10/2023] Open
Abstract
The kindling model has been used extensively by researchers to study the neurobiology of temporal lobe epilepsy (TLE) due to its capacity to induce intensification of seizures by the progressive recruitment of additional neuronal clusters into epileptogenic networks. We applied repetitive focal optogenetic activation of putative excitatory neurons in the dorsal CA1 area of the hippocampus of mice to investigate the role of inhibitory signaling during this process. This experimental protocol resulted in a kindling phenotype that was maintained for 2 weeks after the animals were fully kindled. As a result of the different phases of optogenetic kindling (OpK), key inhibitory signaling elements, such as KCC2 and NKCC1, exhibited distinct temporal and spatial dynamics of regulation. These alterations in protein expression were related to the distinct pattern of ictal activity propagation through the different hippocampal sublayers. Our results suggest the KCC2 disruption in the contralateral hippocampus of fully kindled animals progressively facilitated the creation of pathological pathways for seizure propagation through the hippocampal network. Upon completion of kindling, we observed animals that were restimulated after a rest period of 14-day showed, besides a persistent KCC2 downregulation, an NKCC1 upregulation in the bilateral dentate gyrus and hippocampus-wide loss of parvalbumin-positive interneurons. These alterations observed in the chronic phase of OpK suggest that the hippocampus of rekindled animals continued to undergo self-modifications during the rest period. The changes resulting from this period suggest the possibility of the development of a mirror focus on the hippocampus contralateral to the site of optical stimulations. Our results offer perspectives for preventing the recruitment and conversion of healthy neuronal networks into epileptogenic ones among patients with epilepsy.
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Affiliation(s)
| | | | | | - Hai Sun
- Department of Neurosurgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
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2
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Vasilieva AA, Timechko EE, Lysova KD, Paramonova AI, Yakimov AM, Kantimirova EA, Dmitrenko DV. MicroRNAs as Potential Biomarkers of Post-Traumatic Epileptogenesis: A Systematic Review. Int J Mol Sci 2023; 24:15366. [PMID: 37895044 PMCID: PMC10607802 DOI: 10.3390/ijms242015366] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Structural or post-traumatic epilepsy often develops after brain tissue damage caused by traumatic brain injury, stroke, infectious diseases of the brain, etc. Most often, between the initiating event and epilepsy, there is a period without seizures-a latent period. At this time, the process of restructuring of neural networks begins, leading to the formation of epileptiform activity, called epileptogenesis. The prediction of the development of the epileptogenic process is currently an urgent and difficult task. MicroRNAs are inexpensive and minimally invasive biomarkers of biological and pathological processes. The aim of this study is to evaluate the predictive ability of microRNAs to detect the risk of epileptogenesis. In this study, we conducted a systematic search on the MDPI, PubMed, ScienceDirect, and Web of Science platforms. We analyzed publications that studied the aberrant expression of circulating microRNAs in epilepsy, traumatic brain injury, and ischemic stroke in order to search for microRNAs-potential biomarkers for predicting epileptogenesis. Thus, 31 manuscripts examining biomarkers of epilepsy, 19 manuscripts examining biomarkers of traumatic brain injury, and 48 manuscripts examining biomarkers of ischemic stroke based on circulating miRNAs were analyzed. Three miRNAs were studied: miR-21, miR-181a, and miR-155. The findings showed that miR-21 and miR-155 are associated with cell proliferation and apoptosis, and miR-181a is associated with protein modifications. These miRNAs are not strictly specific, but they are involved in processes that may be indirectly associated with epileptogenesis. Also, these microRNAs may be of interest when they are studied in a cohort with each other and with other microRNAs. To further study the microRNA-based biomarkers of epileptogenesis, many factors must be taken into account: the time of sampling, the type of biological fluid, and other nuances. Currently, there is a need for more in-depth and prolonged studies of epileptogenesis.
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Affiliation(s)
| | | | | | | | | | | | - Diana V. Dmitrenko
- Department of Medical Genetics and Clinical Neurophysiology of Postgraduate Education, V.F. Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk 660022, Russia; (A.A.V.); (E.E.T.); (K.D.L.); (A.I.P.)
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3
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Xu LJ, Wang HN, Zhou H, Li SY, Li F, Miao Y, Lei B, Sun XH, Gao F, Wang Z. EphA4/ephrinA3 reverse signaling induced Müller cell gliosis and production of pro-inflammatory cytokines in experimental glaucoma. Brain Res 2023; 1801:148204. [PMID: 36529265 DOI: 10.1016/j.brainres.2022.148204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/18/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
Previous work showed that ephrinA3/EphA4 forward signaling contributed to retinal ganglion cell (RGC) damage in experimental glaucoma. Since up-regulated patterns of ephrinA3 and EphA4 were observed in Müller cells and RGCs, an EphA4/ephrinA3 reverse signaling may exist in Müller cells of chronic ocular hypertension (COH) retina. We investigated effects of EphA4/ephrinA3 reverse signaling activation on Müller cells in COH retina. Intravitreal injection of the ephrinA3 agonist EphA4-Fc increased glial fibrillary acidic protein (GFAP) levels in normal retinas, suggestive of Müller cell gliosis, which was confirmed in purified cultured Müller cells treated with EphA4-Fc. These effects were mediated by intracellular STAT3 signaling pathway as phosphorylated STAT3 (p-STAT3) levels and ratios of p-STAT3/STAT3 were significantly increased in both COH retinas and EphA4-Fc intravitreally injected retinas, as well as in EphA4-Fc treated purified cultured Müller cells. The increase of GFAP protein levels in EphA4-Fc-injected retinas and EphA4-Fc treated purified cultured Müller cells could be partially eliminated by stattic, a selective STAT3 blocker. Co-immunoprecipitation results testified to the presence of interaction between ephrinA3 and STAT3/p-STAT3. In addition, intravitreal injection of EphA4-Fc or EphA4-Fc treatment of cultured Müller cells significantly up-regulated mRNA and protein contents of pro-inflammatory cytokines. Moreover, intravitreal injection of EphA4-Fc increased the number of apoptotic RGCs, which could be reversed by the tyrosine kinase blocker PP2. Overall, EphA4/ephrinA3 reverse signaling may induce Müller cell gliosis and increases release of pro-inflammatory factors, which could contribute to RGC death in glaucoma. Inhibition of EphA4/ephrinA3 signaling may provide an effective neuroprotection in glaucoma.
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Affiliation(s)
- Lin-Jie Xu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Hong-Ning Wang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Han Zhou
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Shu-Ying Li
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Fang Li
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Yanying Miao
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
| | - Bo Lei
- Institute of Neuroscience and Third Affiliated Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Henan Eye Hospital, People's Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450003, China
| | - Xing-Huai Sun
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China.
| | - Feng Gao
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China.
| | - Zhongfeng Wang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai 200032, China.
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4
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Robb JL, Morrissey NA, Weightman Potter PG, Smithers HE, Beall C, Ellacott KLJ. Immunometabolic Changes in Glia - A Potential Role in the Pathophysiology of Obesity and Diabetes. Neuroscience 2020; 447:167-181. [PMID: 31765625 PMCID: PMC7567742 DOI: 10.1016/j.neuroscience.2019.10.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 12/15/2022]
Abstract
Chronic low-grade inflammation is a feature of the pathophysiology of obesity and diabetes in the CNS as well as peripheral tissues. Glial cells are critical mediators of the response to inflammation in the brain. Key features of glia include their metabolic flexibility, sensitivity to changes in the CNS microenvironment, and ability to rapidly adapt their function accordingly. They are specialised cells which cooperate to promote and preserve neuronal health, playing important roles in regulating the activity of neuronal networks across the brain during different life stages. Increasing evidence points to a role of glia, most notably astrocytes and microglia, in the systemic regulation of energy and glucose homeostasis in the course of normal physiological control and during disease. Inflammation is an energetically expensive process that requires adaptive changes in cellular metabolism and, in turn, metabolic intermediates can also have immunomodulatory actions. Such "immunometabolic" changes in peripheral immune cells have been implicated in contributing to disease pathology in obesity and diabetes. This review will discuss the evidence for a role of immunometabolic changes in glial cells in the systemic regulation of energy and glucose homeostasis, and how this changes in the context of obesity and diabetes.
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Affiliation(s)
- Josephine L Robb
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Nicole A Morrissey
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Paul G Weightman Potter
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Hannah E Smithers
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Craig Beall
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Kate L J Ellacott
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK.
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5
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Das S, Li Z, Noori A, Hyman BT, Serrano-Pozo A. Meta-analysis of mouse transcriptomic studies supports a context-dependent astrocyte reaction in acute CNS injury versus neurodegeneration. J Neuroinflammation 2020; 17:227. [PMID: 32736565 PMCID: PMC7393869 DOI: 10.1186/s12974-020-01898-y] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 07/15/2020] [Indexed: 12/11/2022] Open
Abstract
Background Neuronal damage in acute CNS injuries and chronic neurodegenerative diseases is invariably accompanied by an astrocyte reaction in both mice and humans. However, whether and how the nature of the CNS insult—acute versus chronic—influences the astrocyte response, and whether astrocyte transcriptomic changes in these mouse models faithfully recapitulate the astrocyte reaction in human diseases remains to be elucidated. We hypothesized that astrocytes set off different transcriptomic programs in response to acute versus chronic insults, besides a shared “pan-injury” signature common to both types of conditions, and investigated the presence of these mouse astrocyte signatures in transcriptomic studies from human neurodegenerative diseases. Methods We performed a meta-analysis of 15 published astrocyte transcriptomic datasets from mouse models of acute injury (n = 6) and chronic neurodegeneration (n = 9) and identified pan-injury, acute, and chronic signatures, with both upregulated (UP) and downregulated (DOWN) genes. Next, we investigated these signatures in 7 transcriptomic datasets from various human neurodegenerative diseases. Results In mouse models, the number of UP/DOWN genes per signature was 64/21 for pan-injury and 109/79 for acute injury, whereas only 13/27 for chronic neurodegeneration. The pan-injury-UP signature was represented by the classic cytoskeletal hallmarks of astrocyte reaction (Gfap and Vim), plus extracellular matrix (i.e., Cd44, Lgals1, Lgals3, Timp1), and immune response (i.e., C3, Serping1, Fas, Stat1, Stat2, Stat3). The acute injury-UP signature was enriched in protein synthesis and degradation (both ubiquitin-proteasome and autophagy systems), intracellular trafficking, and anti-oxidant defense genes, whereas the acute injury-DOWN signature included genes that regulate chromatin structure and transcriptional activity, many of which are transcriptional repressors. The chronic neurodegeneration-UP signature was further enriched in astrocyte-secreted extracellular matrix proteins (Lama4, Cyr61, Thbs4), while the DOWN signature included relevant genes such as Agl (glycogenolysis), S1pr1 (immune modulation), and Sod2 (anti-oxidant). Only the pan-injury-UP mouse signature was clearly present in some human neurodegenerative transcriptomic datasets. Conclusions Acute and chronic CNS injuries lead to distinct astrocyte gene expression programs beyond their common astrocyte reaction signature. However, caution should be taken when extrapolating astrocyte transcriptomic findings from mouse models to human diseases.
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Affiliation(s)
- Sudeshna Das
- MGH BioMedical Informatics Core (BMIC), Cambridge, MA, 02139, USA.,Department of Neurology, Massachusetts General Hospital, Boston, MA, 02114, USA.,Massachusetts Alzheimer's Disease Research Center, 114 16th street, Suite 2012, Charlestown, MA, 02129, USA.,Harvard Medical School, Boston, MA, 02116, USA
| | - Zhaozhi Li
- MGH BioMedical Informatics Core (BMIC), Cambridge, MA, 02139, USA.,Department of Neurology, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Ayush Noori
- MGH BioMedical Informatics Core (BMIC), Cambridge, MA, 02139, USA.,Department of Neurology, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Boston, MA, 02114, USA.,Massachusetts Alzheimer's Disease Research Center, 114 16th street, Suite 2012, Charlestown, MA, 02129, USA.,Harvard Medical School, Boston, MA, 02116, USA
| | - Alberto Serrano-Pozo
- Department of Neurology, Massachusetts General Hospital, Boston, MA, 02114, USA. .,Massachusetts Alzheimer's Disease Research Center, 114 16th street, Suite 2012, Charlestown, MA, 02129, USA. .,Harvard Medical School, Boston, MA, 02116, USA.
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6
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Zhang W, Wang X, Yu M, Li JA, Meng H. The c-Jun N-terminal kinase signaling pathway in epilepsy: activation, regulation, and therapeutics. J Recept Signal Transduct Res 2019; 38:492-498. [PMID: 31038026 DOI: 10.1080/10799893.2019.1590410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Epilepsy affects approximately 50-70 million people worldwide and 30-40% of patients do not benefit from medication. Therefore, it is necessary to identify novel targets for epileptic treatments. c-Jun N-terminal kinase (JNK) is a member of the mitogen-activated protein kinase (MAPK) family that activates diverse substrates, such as transcriptional factors, adaptor proteins, and signaling proteins, and has a wide variety of functions in both physiological and pathological conditions. The excessive activation of JNK is found not only in the acute phase of epilepsy, but also in the chronic phase, which potentiates it as a promising target in epilepsy control. In this review, we discuss the activation of the JNK pathway in epilepsy and its role in neuronal death, astrocyte activation, and mossy fiber sprouting (MFS) based on recent updates. Finally, we briefly introduce the current agents that target JNK signaling to control epilepsy.
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Affiliation(s)
- Wuqiong Zhang
- a Department of Neurology and Neuroscience center , The First Hospital of Jilin University , Changchun , P. R. China
| | - Xue Wang
- a Department of Neurology and Neuroscience center , The First Hospital of Jilin University , Changchun , P. R. China
| | - Miaomiao Yu
- a Department of Neurology and Neuroscience center , The First Hospital of Jilin University , Changchun , P. R. China
| | - Jia-Ai Li
- a Department of Neurology and Neuroscience center , The First Hospital of Jilin University , Changchun , P. R. China
| | - Hongmei Meng
- a Department of Neurology and Neuroscience center , The First Hospital of Jilin University , Changchun , P. R. China
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7
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Brenner M, Messing A, Olsen ML. AP-1 and the injury response of the GFAP gene. J Neurosci Res 2018; 97:149-161. [PMID: 30345544 DOI: 10.1002/jnr.24338] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 01/04/2023]
Abstract
Increased GFAP gene expression is a common feature of CNS injury, resulting in its use as a reporter to investigate mechanisms producing gliosis. AP-1 transcription factors are among those proposed to participate in mediating the reactive response. Prior studies found a consensus AP-1 binding site in the GFAP promoter to be essential for activity of reporter constructs transfected into cultured cells, but to have little to no effect on basal transgene expression in mice. Since cultured astrocytes display some properties of reactive astrocytes, these findings suggested that AP-1 transcription factors are critical for the upregulation of GFAP in injury, but not for its resting level of expression. We have examined this possibility by comparing the injury response in mice of lacZ transgenes driven by human GFAP promoters that contain the wild-type AP-1 binding site to those in which the site is mutated. An intact AP-1 site was found critical for a GFAP promoter response to the three different injury models used: physical trauma produced by cryoinjury, seizures produced by kainic acid, and chronic gliosis produced in an Alexander disease model. An unexpected additional finding was that the responses of the lacZ transgenes driven by the wild-type promoters were substantially less than that of the endogenous mouse GFAP gene. This suggests that the GFAP gene has previously unrecognized injury-responsive elements that reside further upstream of the transcription start site than the 2.2 kb present in the GFAP promoter segments used here.
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Affiliation(s)
- Michael Brenner
- Department of Neurobiology and the Civitan International Research Center, Center for Glial Biology in Medicine, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama
| | - Albee Messing
- Department of Comparative Biosciences, Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - Michelle L Olsen
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
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8
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Salazar K, Martínez F, Pérez-Martín M, Cifuentes M, Trigueros L, Ferrada L, Espinoza F, Saldivia N, Bertinat R, Forman K, Oviedo MJ, López-Gambero AJ, Bonansco C, Bongarzone ER, Nualart F. SVCT2 Expression and Function in Reactive Astrocytes Is a Common Event in Different Brain Pathologies. Mol Neurobiol 2017; 55:5439-5452. [PMID: 28942474 DOI: 10.1007/s12035-017-0762-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 08/31/2017] [Indexed: 11/28/2022]
Abstract
Ascorbic acid (AA), the reduced form of vitamin C, acts as a neuroprotector by eliminating free radicals in the brain. Sodium/vitamin C co-transporter isoform 2 (SVCT2) mediates uptake of AA by neurons. It has been reported that SVCT2 mRNA is induced in astrocytes under ischemic damage, suggesting that its expression is enhanced in pathological conditions. However, it remains to be established if SVCT expression is altered in the presence of reactive astrogliosis generated by different brain pathologies. In the present work, we demonstrate that SVCT2 expression is increased in astrocytes present at sites of neuroinflammation induced by intracerebroventricular injection of a GFP-adenovirus or the microbial enzyme, neuraminidase. A similar result was observed at 5 and 10 days after damage in a model of traumatic injury and in the hippocampus and cerebral cortex in the in vivo kindling model of epilepsy. Furthermore, we defined that cortical astrocytes maintained in culture for long periods acquire markers of reactive gliosis and express SVCT2, in a similar way as previously observed in situ. Finally, by means of second harmonic generation and 2-photon fluorescence imaging, we analyzed brain necropsied material from patients with Alzheimer's disease (AD), which presented with an accumulation of amyloid plaques. Strikingly, although AD is characterized by focalized astrogliosis surrounding amyloid plaques, SVCT2 expression at the astroglial level was not detected. We conclude that SVCT2 is heterogeneously induced in reactive astrogliosis generated in different pathologies affecting the central nervous system (CNS).
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Affiliation(s)
- Katterine Salazar
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile.,Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepcion, Chile
| | - Fernando Martínez
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile.,Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepcion, Chile
| | - Margarita Pérez-Martín
- Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, (CIBER-BBN), Malaga, Spain
| | - Manuel Cifuentes
- Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, (CIBER-BBN), Malaga, Spain
| | - Laura Trigueros
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile.,Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, (CIBER-BBN), Malaga, Spain
| | - Luciano Ferrada
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Francisca Espinoza
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Natalia Saldivia
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Romina Bertinat
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Katherine Forman
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - María José Oviedo
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile
| | - Antonio J López-Gambero
- Department of Cell Biology, Genetics and Physiology, University of Malaga, IBIMA, BIONAND, Andalusian Center for Nanomedicine and Biotechnology and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, (CIBER-BBN), Malaga, Spain
| | - Christian Bonansco
- Centro de Neurobiología y Plasticidad Cerebral (CNPC), Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaña Avenida 1111, 2360102, Valparaíso, Chile
| | - Ernesto R Bongarzone
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois Chicago, Chicago, IL, USA.,Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Francisco Nualart
- Laboratory of Neurobiology and Stem Cells NeuroCellT, Department of Cellular Biology, Center for Advanced Microscopy CMA BIO BIO, Faculty of Biological Sciences, University of Concepcion, Concepcion, Chile. .,Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepcion, Chile.
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9
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Tai TY, Warner LN, Jones TD, Jung S, Concepcion FA, Skyrud DW, Fender J, Liu Y, Williams AD, Neumaier JF, D'Ambrosio R, Poolos NP. Antiepileptic action of c-Jun N-terminal kinase (JNK) inhibition in an animal model of temporal lobe epilepsy. Neuroscience 2017; 349:35-47. [PMID: 28237815 DOI: 10.1016/j.neuroscience.2017.02.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 02/10/2017] [Accepted: 02/13/2017] [Indexed: 10/20/2022]
Abstract
Several phosphorylation signaling pathways have been implicated in the pathogenesis of epilepsy arising from both genetic causes and acquired insults to the brain. Identification of dysfunctional signaling pathways in epilepsy may provide novel targets for antiepileptic therapies. We previously described a deficit in phosphorylation signaling mediated by p38 mitogen-activated protein kinase (p38 MAPK) that occurs in an animal model of temporal lobe epilepsy, and that produces neuronal hyperexcitability measured in vitro. We asked whether in vivo pharmacological manipulation of p38 MAPK activity would influence seizure frequency in chronically epileptic animals. Administration of a p38 MAPK inhibitor, SB203580, markedly worsened spontaneous seizure frequency, consistent with prior in vitro results. However, anisomycin, a non-specific p38 MAPK activator, significantly increased seizure frequency. We hypothesized that this unexpected result was due to activation of a related MAPK, c-Jun N-terminal kinase (JNK). Administration of JNK inhibitor SP600125 significantly decreased seizure frequency in a dose-dependent manner without causing overt behavioral abnormalities. Biochemical analysis showed increased JNK expression and activity in untreated epileptic animals. These results show for the first time that JNK is hyperactivated in an animal model of epilepsy, and that phosphorylation signaling mediated by JNK may represent a novel antiepileptic target.
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Affiliation(s)
- Tina Y Tai
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, WA, United States
| | - Lindsay N Warner
- Neurobiology Program, University of Washington, Seattle, WA, United States
| | - Terrance D Jones
- Department of Neurology, University of Washington, Seattle, WA, United States
| | - Sangwook Jung
- Department of Neurology, University of Washington, Seattle, WA, United States
| | | | - David W Skyrud
- Department of Chemistry, Seattle University, Seattle, WA, United States
| | - Jason Fender
- Department of Neurosurgery, University of Washington, Seattle, WA, United States
| | - Yusha Liu
- Departments of Psychiatry and Pharmacology, University of Washington, Seattle, WA, United States
| | - Aaron D Williams
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - John F Neumaier
- Departments of Psychiatry and Pharmacology, University of Washington, Seattle, WA, United States
| | - Raimondo D'Ambrosio
- Department of Neurosurgery, University of Washington, Seattle, WA, United States; Regional Epilepsy Center, University of Washington, Seattle, WA, United States
| | - Nicholas P Poolos
- Department of Neurology, University of Washington, Seattle, WA, United States; Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States; Regional Epilepsy Center, University of Washington, Seattle, WA, United States.
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10
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Repetto IE, Monti R, Tropiano M, Tomasi S, Arbini A, Andrade-Moraes CH, Lent R, Vercelli A. The Isotropic Fractionator as a Tool for Quantitative Analysis in Central Nervous System Diseases. Front Cell Neurosci 2016; 10:190. [PMID: 27547177 PMCID: PMC4974250 DOI: 10.3389/fncel.2016.00190] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 07/19/2016] [Indexed: 01/07/2023] Open
Abstract
One major aim in quantitative and translational neuroscience is to achieve a precise and fast neuronal counting method to work on high throughput scale to obtain reliable results. Here, we tested the isotropic fractionator (IF) method for evaluating neuronal and non-neuronal cell loss in different models of central nervous system (CNS) pathologies. Sprague-Dawley rats underwent: (i) ischemic brain damage; (ii) intraperitoneal injection with kainic acid (KA) to induce epileptic seizures; and (iii) monolateral striatal injection with quinolinic acid (QA) mimicking human Huntington's disease. All specimens were processed for IF method and cell loss assessed. Hippocampus from KA-treated rats and striatum from QA-treated rats were carefully dissected using a dissection microscope and a rat brain matrix. Ischemic rat brains slices were first processed for TTC staining and then for IF. In the ischemic group the cell loss corresponded to the neuronal loss suggesting that hypoxia primarily affects neurons. Combining IF with TTC staining we could correlate the volume of lesion to the neuronal loss; by IF, we could assess that neuronal loss also occurs contralaterally to the ischemic side. In the epileptic group we observed a reduction of neuronal cells in treated rats, but also evaluated the changes in the number of non-neuronal cells in response to the hippocampal damage. In the QA model, there was a robust reduction of neuronal cells on ipsilateral striatum. This neuronal cell loss was not related to a drastic change in the total number of cells, being overcome by the increase in non-neuronal cells, thus suggesting that excitotoxic damage in the striatum strongly activates inflammation and glial proliferation. We concluded that the IF method could represent a simple and reliable quantitative technique to evaluate the effects of experimental lesions mimicking human diseases, and to consider the neuroprotective/anti-inflammatory effects of different treatments in the whole brain and also in discrete regions of interest, with the potential to investigate non-neuronal alterations. Moreover, IF could be used in addition or in substitution to classical stereological techniques or TTC staining used so far, since it is fast, precise and easily combined with complex molecular analysis.
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Affiliation(s)
- Ivan E. Repetto
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of TurinTurin, Italy
| | - Riccardo Monti
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of TurinTurin, Italy
| | - Marta Tropiano
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of TurinTurin, Italy
| | - Simone Tomasi
- Child Study Center, Yale School of Medicine, New HavenCT, USA
| | - Alessia Arbini
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of TurinTurin, Italy
| | | | - Roberto Lent
- Institute of Biomedical Sciences, Federal University of Rio de JaneiroRio de Janeiro, Brazil
| | - Alessandro Vercelli
- Neuroscience Institute Cavalieri Ottolenghi, Department of Neuroscience, University of TurinTurin, Italy
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Zhuo ZH, Sun YZ, Jin PN, Li FY, Zhang YL, Wang HL. Selective targeting of MAPK family kinases JNK over p38 by rationally designed peptides as potential therapeutics for neurological disorders and epilepsy. MOLECULAR BIOSYSTEMS 2016; 12:2532-40. [PMID: 27263470 DOI: 10.1039/c6mb00297h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A systematic strategy is described to optimize peptide selectivity between the MAPK family kinases JNK and p38 for epilepsy therapy.
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Affiliation(s)
- Zhi-Hong Zhuo
- Department of Pediatrics
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Yi-Zhen Sun
- Department of Pediatrics
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Pei-Na Jin
- Department of Pediatrics
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Feng-Yan Li
- Department of Pediatrics
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Yi-Le Zhang
- Reproductive Medical Center
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Huai-Li Wang
- Department of Pediatrics
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
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12
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Lucke-Wold BP, Nguyen L, Turner RC, Logsdon AF, Chen YW, Smith KE, Huber JD, Matsumoto R, Rosen CL, Tucker ES, Richter E. Traumatic brain injury and epilepsy: Underlying mechanisms leading to seizure. Seizure 2015; 33:13-23. [PMID: 26519659 DOI: 10.1016/j.seizure.2015.10.002] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 10/06/2015] [Accepted: 10/08/2015] [Indexed: 02/08/2023] Open
Abstract
Post-traumatic epilepsy continues to be a major concern for those experiencing traumatic brain injury. Post-traumatic epilepsy accounts for 10-20% of epilepsy cases in the general population. While seizure prophylaxis can prevent early onset seizures, no available treatments effectively prevent late-onset seizure. Little is known about the progression of neural injury over time and how this injury progression contributes to late onset seizure development. In this comprehensive review, we discuss the epidemiology and risk factors for post-traumatic epilepsy and the current pharmacologic agents used for treatment. We highlight limitations with the current approach and offer suggestions for remedying the knowledge gap. Critical to this pursuit is the design of pre-clinical models to investigate important mechanistic factors responsible for post-traumatic epilepsy development. We discuss what the current models have provided in terms of understanding acute injury and what is needed to advance understanding regarding late onset seizure. New model designs will be used to investigate novel pathways linking acute injury to chronic changes within the brain. Important components of this transition are likely mediated by toll-like receptors, neuroinflammation, and tauopathy. In the final section, we highlight current experimental therapies that may prove promising in preventing and treating post-traumatic epilepsy. By increasing understanding about post-traumatic epilepsy and injury expansion over time, it will be possible to design better treatments with specific molecular targets to prevent late-onset seizure occurrence following traumatic brain injury.
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Affiliation(s)
- Brandon P Lucke-Wold
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV 26506, USA; The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Linda Nguyen
- Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, WV 26506, USA
| | - Ryan C Turner
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV 26506, USA; The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Aric F Logsdon
- The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA; Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, WV 26506, USA
| | - Yi-Wen Chen
- The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Kelly E Smith
- Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, WV 26506, USA
| | - Jason D Huber
- The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA; Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, WV 26506, USA
| | - Rae Matsumoto
- Department of Basic Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, WV 26506, USA; College of Pharmacy, Touro University California, 1310 Club Drive, Vallejo, CA 94592, USA
| | - Charles L Rosen
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV 26506, USA; The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Eric S Tucker
- The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - Erich Richter
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV 26506, USA; The Center for Neuroscience, West Virginia University School of Medicine, Morgantown, WV 26506, USA.
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13
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Semaan S, Wu J, Gan Y, Jin Y, Li GH, Kerrigan JF, Chang YC, Huang Y. Hyperactivation of BDNF-TrkB signaling cascades in human hypothalamic hamartoma (HH): a potential mechanism contributing to epileptogenesis. CNS Neurosci Ther 2015; 21:164-72. [PMID: 25307426 PMCID: PMC6495156 DOI: 10.1111/cns.12331] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/20/2014] [Accepted: 09/04/2014] [Indexed: 01/26/2023] Open
Abstract
AIMS Although compelling evidence suggests that human hypothalamic hamartoma (HH) is intrinsically epileptogenic for gelastic seizures, the molecular mechanisms responsible for epileptogenesis within HH remain to be elucidated. The aim of this study was to test the hypothesis that hyperactivation of BDNF-TrkB signaling pathways in surgically resected HH tissue is a possible mechanism for downregulation of KCC2 expression, which in turn underlies GABA-mediated excitation within HH. METHODS Activation of three major BDNF-TrkB signaling pathways including MAPKs, Akt, and PLCγ1 were evaluated in surgically resected HH tissue (n = 14) versus human hypothalamic control tissue (n = 8) using combined methodologies of biochemistry, molecular biology, cell biology, and electrophysiology. RESULTS Our data show that compared with hypothalamic control tissue, in HH tissue, (i) activation of TrkB and expression of mature BDNF are elevated; (ii) MAPKs (including ERK1/2, p38, and JNK), Akt, and PLCγ1 are highly activated; (iii) KCC2 expression is downregulated; and (iv) pharmacological manipulation of TrkB signaling alters HH neuronal firing rate. CONCLUSION Our findings suggest that multiple BDNF-TrkB signaling pathways are activated in HH. They act independently or collaboratively to downregulate KCC2 expression, which is the key component for GABA-mediated excitation associated with gelastic seizures.
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Affiliation(s)
- Suzan Semaan
- St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
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14
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Ben J, de Oliveira PA, Gonçalves FM, Peres TV, Matheus FC, Hoeller AA, Leal RB, Walz R, Prediger RD. Effects of Pentylenetetrazole Kindling on Mitogen-Activated Protein Kinases Levels in Neocortex and Hippocampus of Mice. Neurochem Res 2014; 39:2492-500. [DOI: 10.1007/s11064-014-1453-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/07/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
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Analysis of morphological changes as a key method in studying psychiatric animal models. Cell Tissue Res 2013; 354:41-50. [PMID: 23334194 PMCID: PMC3785701 DOI: 10.1007/s00441-012-1547-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 12/05/2012] [Indexed: 12/26/2022]
Abstract
A major interest in the analysis of animal models of psychiatric diseases is their underlying cellular pathology and to gain information regarding whether pharmacological treatments, genetic differences or an altered environment exert an impact upon the brain morphology or on the morphology or activity of single neurones. In this review, several key methods will be introduced that allow the analysis of morphological changes that are frequently observed in psychiatric animal models. An overview of the techniques that enable dendritic arborisation, alterations in dendritic spines and changes in fibre densities to be analysed are described. Moreover, methods for the analysis of adult neurogenesis and neurodegeneration and for the analysis of neuronal activity in fixed brain tissue are described. An important step during the analysis of morphological changes is the estimation of the number of stained cells. Since conventional cell counting methods have several limitations, two different approaches that permit an estimate of the number of stained cells within three-dimensional tissue are also discussed.
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16
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Zhang R, Yang G, Wang Q, Guo F, Wang H. Acylated ghrelin protects hippocampal neurons in pilocarpine-induced seizures of immature rats by inhibiting cell apoptosis. Mol Biol Rep 2012; 40:51-8. [DOI: 10.1007/s11033-012-1993-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 10/01/2012] [Indexed: 01/26/2023]
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17
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Kang WH, Simon MJ, Gao S, Banta S, Morrison B. Attenuation of astrocyte activation by TAT-mediated delivery of a peptide JNK inhibitor. J Neurotrauma 2012; 28:1219-28. [PMID: 21510821 DOI: 10.1089/neu.2011.1879] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Astrocyte activation contributes to the brain's response to disease and injury. Activated astrocytes generate harmful radicals that exacerbate brain damage including nitric oxide, peroxides and superoxides. Furthermore, reactive astrocytes hinder regeneration of damaged neural circuits by secreting neuro-developmental inhibitors and glycosaminoglycans (GAGs), which physically block growth cone extension. Therefore, targeted therapeutic strategies to limit astrocyte activation may enhance recovery from many neurodegenerative states. Previously, we demonstrated that the HIV-1 TAT cell-penetrating peptide, a short non-toxic peptide from the full-length TAT protein, delivered a protein cargo to astrocytes in a process dependent on cell-surface GAG. Since activated astrocytes produce GAG, in this study we tested whether TAT could transduce activated astrocytes, deliver a biologically active cargo, and produce a physiological effect. Astrocyte activation was induced by IL-1β, lipopolysaccharide (LPS), or mechanical stretch injury, and quantified by increased GAG and nitrite content. TAT-mediated delivery of a mock therapeutic protein, GFP, increased significantly after activation. Nitrite production, GAG expression, and GFP-TAT transduction were significantly attenuated by inhibitors of JNK, p38, or ERK. TAT fused to a peptide JNK inhibitor delivered the peptide inhibitor to activated astrocytes and significantly reduced activation. Our study is the first to report significant and direct modulation of astrocyte activation with a peptide JNK inhibitor. Our promising in vitro results warrant in vivo follow-up, as TAT-mediated protein delivery may have broad therapeutic potential for preventing astrocyte activation with the possibility of limiting off-target, negative side effects.
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Affiliation(s)
- Woo Hyeun Kang
- Department of Biomedical, Columbia University, 1210 Amsterdam Avenue, New York, NY 10027, USA.
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18
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Sfondouris JL, Quebedeaux TM, Holdgraf C, Musto AE. Combined process automation for large-scale EEG analysis. Comput Biol Med 2011; 42:129-34. [PMID: 22136696 DOI: 10.1016/j.compbiomed.2011.10.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 10/19/2011] [Accepted: 10/28/2011] [Indexed: 10/15/2022]
Abstract
Epileptogenesis is a dynamic process producing increased seizure susceptibility. Electroencephalography (EEG) data provides information critical in understanding the evolution of epileptiform changes throughout epileptic foci. We designed an algorithm to facilitate efficient large-scale EEG analysis via linked automation of multiple data processing steps. Using EEG recordings obtained from electrical stimulation studies, the following steps of EEG analysis were automated: (1) alignment and isolation of pre- and post-stimulation intervals, (2) generation of user-defined band frequency waveforms, (3) spike-sorting, (4) quantification of spike and burst data and (5) power spectral density analysis. This algorithm allows for quicker, more efficient EEG analysis.
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Affiliation(s)
- John L Sfondouris
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, 2020 Gravier Street, New Orleans, LA 70112, USA
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19
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Bazan NG, Musto AE, Knott EJ. Endogenous signaling by omega-3 docosahexaenoic acid-derived mediators sustains homeostatic synaptic and circuitry integrity. Mol Neurobiol 2011; 44:216-22. [PMID: 21918832 PMCID: PMC3180614 DOI: 10.1007/s12035-011-8200-6] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 08/22/2011] [Indexed: 01/22/2023]
Abstract
The harmony and function of the complex brain circuits and synapses are sustained mainly by excitatory and inhibitory neurotransmission, neurotrophins, gene regulation, and factors, many of which are incompletely understood. A common feature of brain circuit components, such as dendrites, synaptic membranes, and other membranes of the nervous system, is that they are richly endowed in docosahexaenoic acid (DHA), the main member of the omega-3 essential fatty acid family. DHA is avidly retained and concentrated in the nervous system and known to play a role in neuroprotection, memory, and vision. Only recently has it become apparent why the surprisingly rapid increases in free (unesterified) DHA pool size take place at the onset of seizures or brain injury. This phenomenon began to be clarified by the discovery of neuroprotectin D1 (NPD1), the first-uncovered bioactive docosanoid formed from free DHA through 15-lipoxygenase-1 (15-LOX-1). NPD1 synthesis includes, as agonists, oxidative stress and neurotrophins. The evolving concept is that DHA-derived docosanoids set in motion endogenous signaling to sustain homeostatic synaptic and circuit integrity. NPD1 is anti-inflammatory, displays inflammatory resolving activities, and induces cell survival, which is in contrast to the pro-inflammatory actions of the many of omega-6 fatty acid family members. We highlight here studies relevant to the ability of DHA to sustain neuronal function and protect synapses and circuits in the context of DHA signalolipidomics. DHA signalolipidomics comprises the integration of the cellular/tissue mechanism of DHA uptake, its distribution among cellular compartments, the organization and function of membrane domains containing DHA phospholipids, and the precise cellular and molecular events revealed by the uncovering of signaling pathways regulated by docosanoids endowed with prohomeostatic and cell survival bioactivity. Therefore, this approach offers emerging targets for prevention, pharmaceutical intervention, and clinical translation involving DHA-mediated signaling.
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Affiliation(s)
- Nicolas G Bazan
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite D, New Orleans, LA, 70112, USA,
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20
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Musto AE, Gjorstrup P, Bazan NG. The omega-3 fatty acid-derived neuroprotectin D1 limits hippocampal hyperexcitability and seizure susceptibility in kindling epileptogenesis. Epilepsia 2011; 52:1601-8. [PMID: 21569016 DOI: 10.1111/j.1528-1167.2011.03081.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Temporal lobe epilepsy, one of the most common epilepsy syndromes, is characterized by hippocampal hyperexcitability and progressive seizure susceptibility. Omega-3 fatty acids are involved in neuronal excitability and have anticonvulsant properties. We studied the effect of docosahexaenoic acid (DHA) or its derived lipid mediator, neuroprotectin D1 (NPD1, 10R,17S-dihydroxy-docosa-4Z,7Z,11E,13E,15Z,19Z-hexaenoic acid), in evoked seizures using a rapid kindling model of temporal lobe epilepsy. METHODS DHA or NPD1 was administered in rodents with or without kindling acquisition. Locomotor seizures and evoked epileptiform hippocampal activity immediately after hippocampal stimulations were analyzed. KEY FINDINGS DHA or NPD1 limits hippocampal electrically induced hyperexcitability. Seizures induced by kindling triggered NPD1 synthesis in the hippocampus. Supplying its precursor, DHA, or direct injection of NPD1 into the third ventricle resulted in attenuation of kindling progression and hippocampal hyperexcitability. SIGNIFICANCE The significance of NPD1 in temporal lobe epilepsy could open new pathways for understanding the initiation and propagation of seizures and the role this lipid mediator plays in the neuronal network.
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Affiliation(s)
- Alberto E Musto
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
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21
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Takemiya T, Matsumura K, Sugiura H, Yasuda S, Uematsu S, Akira S, Yamagata K. Endothelial microsomal prostaglandin E synthase-1 facilitates neurotoxicity by elevating astrocytic Ca2+ levels. Neurochem Int 2011; 58:489-96. [PMID: 21219953 DOI: 10.1016/j.neuint.2011.01.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Revised: 01/04/2011] [Accepted: 01/04/2011] [Indexed: 11/29/2022]
Abstract
Recurrent seizures may cause neuronal damage in the hippocampus. As neurons form intimate interactions with astrocytes via glutamate, this neuron-glia circuit may play a pivotal role in neuronal excitotoxicity following such seizures. On the other hand, astrocytes contact vascular endothelia with their endfeet. Recently, we found kainic acid (KA) administration induced microsomal prostaglandin E synthase-1 (mPGES-1) and prostaglandin E(2) (PGE(2)) receptor EP3 in venous endothelia and on astrocytes, respectively. In addition, mice deficient in mPGES-1 exhibited an improvement in KA-induced neuronal loss, suggesting that endothelial PGE(2) might modulate neuronal damage via astrocytes. In this study, we therefore investigated whether the functional associations between endothelia and astrocytes via endothelial mPGES-1 lead to neuronal injury using primary cultures of hippocampal slices. We first confirmed the delayed induction of endothelial mPGES-1 in the wild-type (WT) slices after KA-treatment. Next, we examined the effects of endothelial mPGES-1 on Ca(2+) levels in astrocytes, subsequent glutamate release and neuronal injury using cultured slices prepared from WT and mPGES-1 knockout mice. Moreover, we investigated which EP receptor on astrocytes was activated by PGE(2). We found that endothelial mPGES-1 produced PGE(2) that enhanced astrocytic Ca(2+) levels via EP3 receptors and increased Ca(2+)-dependent glutamate release, aggravating neuronal injury. This novel endothelium-astrocyte-neuron signaling pathway may be crucial for neuronal damage after repetitive seizures, and hence could be a new target for drug development.
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Affiliation(s)
- Takako Takemiya
- Medical Research Institute, Tokyo Women's Medical University, Shinjuku, Tokyo, Japan.
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22
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Musto AE, Samii M. Platelet-activating factor receptor antagonism targets neuroinflammation in experimental epilepsy. Epilepsia 2011; 52:551-61. [PMID: 21204830 DOI: 10.1111/j.1528-1167.2010.02920.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE Temporal lobe epilepsy is associated with the inflammatory process related to the basic mechanisms that lead to seizure susceptibility and brain damage. Platelet-activating factor (PAF), a potent, short-lived phospholipid mediator of inflammation, participates in physiologic signaling in the brain. However, after seizures, PAF accumulates in the brain and activates intracellular signaling related with inflammation-mediated excitotoxicity and hippocampal hyperexcitability. The objective of this study is to evaluate the effect of PAF antagonism on hippocampal hyperexcitability, seizure susceptibility, and neuroprotection using the kindling paradigm and pilocarpine-induced seizure damage models. METHODS The PAF antagonist, LAU-0901 (60 mg/kg, i.p.), or vehicle, was administrated each day of kindling or daily during the 4 weeks after status epilepticus (SE). We analyzed seizure severity, electrical activity, cellular damage, and inflammation in the hippocampi of both treated groups. KEY FINDINGS LAU-0901 limits the progression of kindling and attenuates seizure susceptibility 1 week after the kindling procedure. In addition, under the seizure-damage conditions studied here, we observed that LAU-0901 induces hippocampal neuroprotection and limits somatostatin interneuronal cell loss and inflammation. SIGNIFICANCE Our results indicate that modulation of PAF overactivity attenuates seizure susceptibility, hippocampal hyperexcitability, and neuroinflammation.
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Affiliation(s)
- Alberto E Musto
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, School of Medicine, New Orleans, Louisiana 70112, USA.
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Hippocampal c-Jun-N-terminal kinases serve as negative regulators of associative learning. J Neurosci 2010; 30:13348-61. [PMID: 20926661 DOI: 10.1523/jneurosci.3492-10.2010] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
In the adult mouse, signaling through c-Jun N-terminal kinases (JNKs) links exposure to acute stress to various physiological responses. Inflammatory cytokines, brain injury and ischemic insult, or exposure to psychological acute stressors induce activation of hippocampal JNKs. Here we report that exposure to acute stress caused activation of JNKs in the hippocampal CA1 and CA3 subfields, and impaired contextual fear conditioning. Conversely, intrahippocampal injection of JNKs inhibitors sp600125 (30 μm) or D-JNKI1 (8 μm) reduced activity of hippocampal JNKs and rescued stress-induced deficits in contextual fear. In addition, intrahippocampal administration of anisomycin (100 μg/μl), a potent JNKs activator, mimicked memory-impairing effects of stress on contextual fear. This anisomycin-induced amnesia was abolished after cotreatment with JNKs selective inhibitor sp600125 without affecting anisomycin's ability to effectively inhibit protein synthesis as measured by c-Fos immunoreactivity. We also demonstrated milder and transient activation of the JNKs pathway in the CA1 subfield of the hippocampus during contextual fear conditioning and an enhancement of contextual fear after pharmacological inhibition of JNKs under baseline conditions. Finally, using combined biochemical and transgenic approaches with mutant mice lacking different members of the JNK family (Jnk1, Jnk2, and Jnk3), we provided evidence that JNK2 and JNK3 are critically involved in stress-induced deficit of contextual fear, while JNK1 mainly regulates baseline learning in this behavioral task. Together, these results support the possibility that hippocampal JNKs serve as a critical molecular regulator in the formation of contextual fear.
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Liu G, Guo H, Guo C, Zhao S, Gong D, Zhao Y. Involvement of IRE1α signaling in the hippocampus in patients with mesial temporal lobe epilepsy. Brain Res Bull 2010; 84:94-102. [PMID: 20965234 DOI: 10.1016/j.brainresbull.2010.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 09/17/2010] [Accepted: 10/12/2010] [Indexed: 10/18/2022]
Abstract
Cumulative evidence suggests that programmed cell death (apoptosis) may contribute to the progressive hippocampal sclerosis seen in patients with refractory mesial temporal lobe epilepsy (MTLE). The endoplasmic reticulum (ER) stress-mediated cell apoptotic pathway has recently emerged as a vital intrinsic pathway, but the molecular mechanisms underlying this process in the epileptic brain remain unclear. We investigated inositol-requiring protein 1α (IRE1α)-mediated ER stress pro-and anti-apoptotic signaling pathways in resected hippocampi from 32 patients with intractable MTLE. Immunoreactivity for the ER stress markers glucose-regulated proteins 78 and 94 was significantly higher in MTLE hippocampi than in controls. The levels of IRE1α, tumor necrosis factor receptor associated factor 2 (TRAF2), apoptosis signal-regulating kinase 1 (ASK1) and c-Jun N-terminal kinase (JNK), which together constitute the IRE1α/TRAF2/ASK1/JNK pro-apoptotic signaling pathway, were significantly upregulated in patients with MTLE. Immunoreactivity for caspase-4, a homologue of caspase-12 that is possibly activated by IRE1α via TRAF2 following ER stress, and caspase-3 which was a downstream effector of caspase-4, were both detected in MTLE tissue samples. In contrast, immunoreactivity for caspase-4 and caspase-3 were low or absent in control samples. Simultaneously, the X-box binding protein 1 (XBP1), a basic leucine zipper (bZIP) family transcription factor downstream of IRE1α which can promote cell survival by upregulation of multiple ER-targeted genes, was also overexpressed and activated in MTLE hippocampi. Our data suggest that chronic epilepsy is associated with ER stress, as well as induction of both IRE1α-mediated pro- and anti-apoptotic signaling pathways.
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Affiliation(s)
- Gonglu Liu
- Department of Neurology, Shanghai Jiaotong University Affiliated First People's Hospital, Hongkou District, PR China
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Mehan S, Meena H, Sharma D, Sankhla R. JNK: A Stress-Activated Protein Kinase Therapeutic Strategies and Involvement in Alzheimer’s and Various Neurodegenerative Abnormalities. J Mol Neurosci 2010; 43:376-90. [DOI: 10.1007/s12031-010-9454-6] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 09/16/2010] [Indexed: 01/26/2023]
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Chen X, Wu J, Hua D, Shu K, Wang JZ, Li L, Lei T. The c-Jun N-terminal kinase inhibitor SP600125 is neuroprotective in amygdala kindled rats. Brain Res 2010; 1357:104-14. [PMID: 20692238 DOI: 10.1016/j.brainres.2010.07.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Revised: 07/21/2010] [Accepted: 07/22/2010] [Indexed: 11/25/2022]
Abstract
c-Jun N-terminal kinase (JNK) is implicated in cell death in neurodegenerative disorders and has been taken as a critical point between the physiological and pathological status. JNK specific inhibitor SP600125 has been found to have a protective effect against transient brain ischemia/reperfusion-induced neuronal death in rat hippocampal CA1 region. Former studies have shown the relation between JNK phosphorylation and neuronal damage in models of brain ischemia or in chemically or acute electrically kindled animal in which the stimulus-induced JNK phosphorylation was temporary or transient. In this study, the effect of repeated activation of JNK was examined in the amygdala kindled rats, under or without intraventrical infusion of SP600125, compared with the sham control. JNK phosphorylation was detected by Western blot and immunofluorescent staining in hippocampal extracts and in slices respectively. Nissl staining was performed to detect the neuronal defect. We found that the level of JNK phosphorylation (46KD) in the hippocampus increased in the amygdala kindled rats, whereas such JNK phosphorylation could be inhibited by SP600125. Expression of total JNK in the hippocampus remained unchanged in kindled rats compared with the sham control, and was not affected by SP600125. Neuronal defect was marked in the kindling group and in the vehicle DMSO group, and was alleviated under the administration of SP600125. These findings suggest that JNK phosphorylation is involved in the process of hippocampal sclerosis in the mesial temporal lobe epilepsy (TLE). JNK signaling pathway may be a new target to interfere with the development of hippocampal sclerosis in the temporal lobe epilepsy. The JNK inhibitor SP600125 can show a protective effect on hippocampal neurons in TLE by inhibiting JNK activation.
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Affiliation(s)
- Xu Chen
- Department of Neurosurgery, Tongji Hospital, Huazhong University of Science and Technology, Jiefang Ave 1095, 430030 Wuhan, China
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Wines-Samuelson M, Schulte EC, Smith MJ, Aoki C, Liu X, Kelleher RJ, Shen J. Characterization of age-dependent and progressive cortical neuronal degeneration in presenilin conditional mutant mice. PLoS One 2010; 5:e10195. [PMID: 20419112 PMCID: PMC2855368 DOI: 10.1371/journal.pone.0010195] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Accepted: 03/15/2010] [Indexed: 11/18/2022] Open
Abstract
Presenilins are the major causative genes of familial Alzheimer's disease (AD). Our previous study has demonstrated essential roles of presenilins in memory and neuronal survival. Here, we explore further how loss of presenilins results in age-related, progressive neurodegeneration in the adult cerebral cortex, where the pathogenesis of AD occurs. To circumvent the requirement of presenilins for embryonic development, we used presenilin conditional double knockout (Psen cDKO) mice, in which presenilin inactivation is restricted temporally and spatially to excitatory neurons of the postnatal forebrain beginning at 4 weeks of age. Increases in the number of degenerating (Fluoro-Jade B+, 7.6-fold) and apoptotic (TUNEL+, 7.4-fold) neurons, which represent approximately 0.1% of all cortical neurons, were first detected at 2 months of age when there is still no significant loss of cortical neurons and volume in Psen cDKO mice. By 4 months of age, significant loss of cortical neurons (approximately 9%) and gliosis was found in Psen cDKO mice. The apoptotic cell death is associated with caspase activation, as shown by increased numbers of cells immunoreactive for active caspases 9 and 3 in the Psen cDKO cortex. The vulnerability of cortical neurons to loss of presenilins is region-specific with cortical neurons in the lateral cortex most susceptible. Compared to the neocortex, the increase in apoptotic cell death and the extent of neurodegeneration are less dramatic in the Psen cDKO hippocampus, possibly in part due to increased neurogenesis in the aging dentate gyrus. Neurodegeneration is also accompanied with mitochondrial defects, as indicated by reduced mitochondrial density and altered mitochondrial size distribution in aging Psen cortical neurons. Together, our findings show that loss of presenilins in cortical neurons causes apoptotic cell death occurring in a very small percentage of neurons, which accumulates over time and leads to substantial loss of cortical neurons in the aging brain. The low occurrence and significant delay of apoptosis among cortical neurons lacking presenilins suggest that loss of presenilins may induce apoptotic neuronal death through disruption of cellular homeostasis rather than direct activation of apoptosis pathways.
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Affiliation(s)
- Mary Wines-Samuelson
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Eva C. Schulte
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Miriam J. Smith
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Chiye Aoki
- Center for Neural Science, New York University, New York, New York, United States of America
| | - Xinran Liu
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Raymond J. Kelleher
- Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jie Shen
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
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Spigolon G, Veronesi C, Bonny C, Vercelli A. c-Jun N-terminal kinase signaling pathway in excitotoxic cell death following kainic acid-induced status epilepticus. Eur J Neurosci 2010; 31:1261-72. [DOI: 10.1111/j.1460-9568.2010.07158.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Kelm RF, Wagenführer J, Schmidtmann I, Engelhard K, Werner C, Noppens RR. Transpulmonary cardiac output measurement in a rat model of cardiac arrest and CPR: Impact of vascular access. Resuscitation 2010; 81:248-54. [DOI: 10.1016/j.resuscitation.2009.10.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 10/17/2009] [Accepted: 10/25/2009] [Indexed: 01/25/2023]
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Bazan NG. Is NF-kappa B from astrocytes a decision maker of neuronal life or death? (Commentary on Dvoriantchikova et al.). Eur J Neurosci 2009; 30:173-4. [PMID: 19614977 DOI: 10.1111/j.1460-9568.2009.06853.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nicolas G Bazan
- Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, School of Medicine, New Orleans, LA, USA
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Haeusgen W, Boehm R, Zhao Y, Herdegen T, Waetzig V. Specific activities of individual c-Jun N-terminal kinases in the brain. Neuroscience 2009; 161:951-9. [DOI: 10.1016/j.neuroscience.2009.04.014] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Revised: 04/06/2009] [Accepted: 04/06/2009] [Indexed: 12/31/2022]
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Repeated hypoxic episodes induce seizures and alter hippocampal network activities in mice. Neuroscience 2009; 161:599-613. [DOI: 10.1016/j.neuroscience.2009.03.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 02/08/2009] [Accepted: 03/15/2009] [Indexed: 11/23/2022]
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Musto AE, Samii MS, Hayes JF. Different phases of afterdischarge during rapid kindling procedure in mice. Epilepsy Res 2009; 85:199-205. [PMID: 19375287 DOI: 10.1016/j.eplepsyres.2009.02.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 02/17/2009] [Accepted: 02/27/2009] [Indexed: 11/24/2022]
Abstract
The basic mechanisms of hippocampal networks in epileptogenesis are not entirely understood. To help achieve a better understanding of these mechanisms, we studied the extra-cellular electrically evoked responses in the hippocampi of mice during rapid kindling. Kindling protocol was achieved by stimulating the dorsal right hippocampus six times daily for four days using bipolar electrodes to produce sub-convulsive electrical discharges. Motor responses and analyzed electroencephalographic recordings showed progression from partial complex seizures to generalized seizures associated with different consecutive patterns within the afterdischarges. A spike-wave pattern appeared immediately after stimulation in combination with a poly-spike complex superimposed over the wave (AD1). AD1 was followed by a poly-spike complex (AD2), which was followed by a progressive modification of repetitive spikes (AD3). An ictal depression event was observed at the end of each AD3. Theta oscillations were observed at stage 1-2 of kindling, while beta/gamma oscillations appeared within AD2, associated with stage 4-5 from Racine's score. Benzodiazepine, a GABA (A) agonist (Diazepam) administered at non-sedative doses and only on days 3 and 4 of kindling, limited beta and gamma frequency bands and the progression of seizure severity, suggesting that the failure of GABA (A) agonism mediates the propagation or generalization of seizures. We conclude that different phases of afterdischarge occur during kindling and that high frequencies mediate generalization of seizures.
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Affiliation(s)
- Alberto E Musto
- Department of Neurosurgery, Louisiana State University Health Sciences Center, 2020 Gravier Street, Suite D, New Orleans, LA 70112, USA.
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A Drosophila systems model of pentylenetetrazole induced locomotor plasticity responsive to antiepileptic drugs. BMC SYSTEMS BIOLOGY 2009; 3:11. [PMID: 19154620 PMCID: PMC2657775 DOI: 10.1186/1752-0509-3-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 01/21/2009] [Indexed: 11/21/2022]
Abstract
Background Rodent kindling induced by PTZ is a widely used model of epileptogenesis and AED testing. Overlapping pathophysiological mechanisms may underlie epileptogenesis and other neuropsychiatric conditions. Besides epilepsy, AEDs are widely used in treating various neuropsychiatric disorders. Mechanisms of AEDs' long term action in these disorders are poorly understood. We describe here a Drosophila systems model of PTZ induced locomotor plasticity that is responsive to AEDs. Results We empirically determined a regime in which seven days of PTZ treatment and seven days of subsequent PTZ discontinuation respectively cause a decrease and an increase in climbing speed of Drosophila adults. Concomitant treatment with NaVP and LEV, not ETH, GBP and VGB, suppressed the development of locomotor deficit at the end of chronic PTZ phase. Concomitant LEV also ameliorated locomotor alteration that develops after PTZ withdrawal. Time series of microarray expression profiles of heads of flies treated with PTZ for 12 hrs (beginning phase), two days (latent phase) and seven days (behaviorally expressive phase) showed only down-, not up-, regulation of genes; expression of 23, 2439 and 265 genes were downregulated, in that order. GO biological process enrichment analysis showed downregulation of transcription, neuron morphogenesis during differentiation, synaptic transmission, regulation of neurotransmitter levels, neurogenesis, axonogenesis, protein modification, axon guidance, actin filament organization etc. in the latent phase and of glutamate metabolism, cell communication etc. in the expressive phase. Proteomic interactome based analysis provided further directionality to these events. Pathway overrepresentation analysis showed enrichment of Wnt signaling and other associated pathways in genes downregulated by PTZ. Mining of available transcriptomic and proteomic data pertaining to established rodent models of epilepsy and human epileptic patients showed overrepresentation of epilepsy associated genes in our PTZ regulated set. Conclusion Systems biology ultimately aims at delineating and comprehending the functioning of complex biological systems in such details that predictive models of human diseases could be developed. Due to immense complexity of higher organisms, systems biology approaches are however currently focused on simpler organisms. Amenable to modeling, our model offers a unique opportunity to further dissect epileptogenesis-like plasticity and to unravel mechanisms of long-term action of AEDs relevant in neuropsychiatric disorders.
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Endothelin-1 regulates astrocyte proliferation and reactive gliosis via a JNK/c-Jun signaling pathway. J Neurosci 2008; 28:2394-408. [PMID: 18322086 DOI: 10.1523/jneurosci.5652-07.2008] [Citation(s) in RCA: 197] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Reactive gliosis is characterized by enhanced glial fibrillary acidic protein (GFAP) expression, cellular hypertrophy, and astrocyte proliferation. The cellular and molecular mechanisms underlying this process are still largely undefined. We investigated the role of endothelin-1 (ET-1) in reactive gliosis in corpus callosum after lysolecithin (LPC)-induced focal demyelination and in cultured astrocytes. We show that ET-1 levels are upregulated in demyelinated lesions within 5 d after LPC injection, together with enhanced astrocyte proliferation, GFAP expression, and JNK phosphorylation. Infusion of the pan-ET-receptor (ET-R) antagonist Bosentan or the selective ET(B)-R antagonist BQ788 into the corpus callosum prevented postlesion astrocyte proliferation and JNK phosphorylation. In cultured astrocytes, ET-1-induced activation of ET(B)-Rs promotes a reactive phenotype by enhancing both GFAP expression and astrocyte proliferation. In the same cells, ET-1 activates both JNK and p38MAPK pathways, and induces c-Jun expression at the mRNA and protein levels. By using selective pharmacological inhibitors, we also provide evidence that ET-1 induces astrocyte proliferation and GFAP expression through activation of ERK- and JNK-dependent pathways, consistent with the previous observation of ET-1-induced activation of ERK (Schinelli et al., 2001). Finally, we show by gain and loss of function that increased c-Jun expression enhances the proliferative response of astrocytes to ET-1, whereas c-jun siRNA prevents ET-1-induced cell proliferation. Our results indicate that the effects of ET-1 on astrocyte proliferation depend on c-Jun induction and activation through ERK- and JNK-dependent pathways, and suggest that ET-R-associated pathways might represent important targets to control reactive gliosis.
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Mangiola A, Lama G, Giannitelli C, De Bonis P, Anile C, Lauriola L, La Torre G, Sabatino G, Maira G, Jhanwar-Uniyal M, Sica G. Stem Cell Marker Nestin and c-Jun NH2-Terminal Kinases in Tumor and Peritumor Areas of Glioblastoma Multiforme: Possible Prognostic Implications. Clin Cancer Res 2007; 13:6970-7. [DOI: 10.1158/1078-0432.ccr-07-1229] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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