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Li X, Yennawar M, Wiest A, O'Brien WT, Babrowicz B, White RS, Talos DM, Jensen FE. Cannabidiol attenuates seizure susceptibility and behavioural deficits in adult CDKL5 R59X knock-in mice. Eur J Neurosci 2024. [PMID: 38654472 DOI: 10.1111/ejn.16350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 02/15/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024]
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is caused by a loss-of-function mutation in CDKL5 gene, encoding a serine-threonine kinase highly expressed in the brain. CDD manifests with early-onset epilepsy, autism, motor impairment and severe intellectual disability. While there are no known treatments for CDD, the use of cannabidiol has recently been introduced into clinical practice for neurodevelopmental disorders. Given the increased clinical utilization of cannabidiol, we examined its efficacy in the CDKL5R59X knock-in (R59X) mice, a CDD model based on a human mutation that exhibits both lifelong seizure susceptibility and behavioural deficits. We found that cannabidiol pre-treatment rescued the increased seizure susceptibility in response to the chemoconvulsant pentylenetetrazol (PTZ), attenuated working memory and long-term memory impairments, and rescued social deficits in adult R59X mice. To elucidate a potential mechanism, we compared the developmental hippocampal and cortical expression of common endocannabinoid (eCB) targets in R59X mice and their wild-type littermates, including cannabinoid type 1 receptor (CB1R), transient receptor potential vanilloid type 1 (TRPV1) and 2 (TRPV2), G-coupled protein receptor 55 (GPR55) and adenosine receptor 1 (A1R). Many of these eCB targets were developmentally regulated in both R59X and wild-type mice. In addition, adult R59X mice demonstrated significantly decreased expression of CB1R and TRPV1 in the hippocampus, and TRPV2 in the cortex, while TRPV1 was increased in the cortex. These findings support the potential for dysregulation of eCB signalling as a plausible mechanism and therapeutic target in CDD, given the efficacy of cannabidiol to attenuate hyperexcitability and behavioural deficits in this disorder.
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Affiliation(s)
- Xiaofan Li
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Madhumita Yennawar
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Alyssa Wiest
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - William T O'Brien
- Neurobehavior Testing Core, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Bergan Babrowicz
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rachel S White
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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2
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Schneider ALC, Law CA, Gottesman RF, Krauss G, Huang J, Kucharska-Newton A, Jensen FE, Gugger JJ, Diaz-Arrastia R, Johnson EL. Posttraumatic Epilepsy and Dementia Risk. JAMA Neurol 2024:2815567. [PMID: 38407883 PMCID: PMC10897826 DOI: 10.1001/jamaneurol.2024.0010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Importance Although both head injury and epilepsy are associated with long-term dementia risk, posttraumatic epilepsy (PTE) has only been evaluated in association with short-term cognitive outcomes. Objective To investigate associations of PTE with dementia risk. Design, Setting, and Participants The Atherosclerosis Risk in Communities (ARIC) study initially enrolled participants from 1987 to 1989 and this prospective cohort study uses data through December 31, 2019, with a median follow-up of 25 years. Data were analyzed between March 14, 2023, and January 2, 2024. The study took place in 4 US communities in Minnesota, Maryland, North Carolina, and Mississippi. Of 15 792 ARIC study participants initially enrolled, 2061 were ineligible and 1173 were excluded for missing data, resulting in 12 558 included participants. Exposures Head injury was defined by self-report and International Classification of Diseases (ICD) diagnostic codes. Seizure/epilepsy was defined using ICD codes. PTE was defined as a diagnosis of seizure/epilepsy occurring more than 7 days after head injury. Head injury, seizure/epilepsy, and PTE were analyzed as time-varying exposures. Main Outcomes and Measures Dementia was defined using cognitive assessments, informant interviews, and ICD and death certificate codes. Adjusted Cox and Fine and Gray proportional hazards models were used to estimate dementia risk. Results Participants had a mean (SD) age of 54.3 (5.8) years at baseline, 57.7% were female, 28.2% were of self-reported Black race, 14.4% were ultimately categorized as having head injury, 5.1% as having seizure/epilepsy, and 1.2% as having PTE. Over a median follow-up of 25 (25th to 75th percentile, 17-30) years, 19.9% developed dementia. In fully adjusted models, compared with no head injury and no seizure/epilepsy, PTE was associated with 4.56 (95% CI, 4.49-5.95) times the risk of dementia, while seizure/epilepsy was associated with 2.61 (95% CI, 2.21-3.07) times the risk and head injury with 1.63 (95% CI, 1.47-1.80) times the risk. The risk of dementia associated with PTE was significantly higher than the risk associated with head injury alone and with nontraumatic seizure/epilepsy alone. Results were slightly attenuated in models accounting for the competing risks of mortality and stroke, but patterns of association remained similar. In secondary analyses, the increased dementia risk associated with PTE occurring after first vs second head injury and after mild vs moderate/severe injury was similar. Conclusions and Relevance In this community-based cohort, there was an increased risk of dementia associated with PTE that was significantly higher than the risk associated with head injury or seizure/epilepsy alone. These findings provide evidence that PTE is associated with long-term outcomes and supports both the prevention of head injuries via public health measures and further research into the underlying mechanisms and the risk factors for the development of PTE, so that efforts can also be focused on the prevention of PTE after a head injury.
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Affiliation(s)
- Andrea L C Schneider
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
- Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Connor A Law
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Rebecca F Gottesman
- Intramural Research Program, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland
| | - Gregory Krauss
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Juebin Huang
- Department of Neurology, University of Mississippi Medical Center, Jackson
| | - Anna Kucharska-Newton
- Department of Epidemiology, University of North Carolina Chapel Hill Gilling School of Global Public Health, Chapel Hill
| | - Frances E Jensen
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - James J Gugger
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Ramon Diaz-Arrastia
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Emily L Johnson
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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3
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Xing B, Barbour AJ, Vithayathil J, Li X, Dutko S, Fawcett-Patel J, Lancaster E, Talos DM, Jensen FE. Reversible synaptic adaptations in a subpopulation of murine hippocampal neurons following early-life seizures. J Clin Invest 2024; 134:e175167. [PMID: 38227384 PMCID: PMC10904056 DOI: 10.1172/jci175167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 01/11/2024] [Indexed: 01/17/2024] Open
Abstract
Early-life seizures (ELSs) can cause permanent cognitive deficits and network hyperexcitability, but it is unclear whether ELSs induce persistent changes in specific neuronal populations and whether these changes can be targeted to mitigate network dysfunction. We used the targeted recombination of activated populations (TRAP) approach to genetically label neurons activated by kainate-induced ELSs in immature mice. The ELS-TRAPed neurons were mainly found in hippocampal CA1, remained uniquely susceptible to reactivation by later-life seizures, and displayed sustained enhancement in α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated (AMPAR-mediated) excitatory synaptic transmission and inward rectification. ELS-TRAPed neurons, but not non-TRAPed surrounding neurons, exhibited enduring decreases in Gria2 mRNA, responsible for encoding the GluA2 subunit of the AMPARs. This was paralleled by decreased synaptic GluA2 protein expression and heightened phosphorylated GluA2 at Ser880 in dendrites, indicative of GluA2 internalization. Consistent with increased GluA2-lacking AMPARs, ELS-TRAPed neurons showed premature silent synapse depletion, impaired long-term potentiation, and impaired long-term depression. In vivo postseizure treatment with IEM-1460, an inhibitor of GluA2-lacking AMPARs, markedly mitigated ELS-induced changes in TRAPed neurons. These findings show that enduring modifications of AMPARs occur in a subpopulation of ELS-activated neurons, contributing to synaptic dysplasticity and network hyperexcitability, but are reversible with early IEM-1460 intervention.
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McArthur JC, Augustine EF, Carmichael ST, Ferriero DM, Jensen FE, Jeste SS, Jordan LC, Llinas RH, Schlaggar BL, Sun LR, Pomeroy SL. Recognizing and Responding to the Needs of Future Child and Adult Neurology Care Through the Evolution of Residency Training. Ann Neurol 2023; 94:1005-1007. [PMID: 37755722 DOI: 10.1002/ana.26809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 09/28/2023]
Abstract
Recent insights into the frequency of occurrence and the genetic and mechanistic basis of nervous system disease have demonstrated that neurologic disorders occur as a spectrum across all ages. To meet future needs of patients with neurologic disease of all ages and prepare for increasing implementaton of precision therapies, greater integration of child and adult neurology residency training is needed. ANN NEUROL 2023;94:1005-1007.
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Affiliation(s)
| | - Erika F Augustine
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Kennedy Krieger Institute, Baltimore, MD, USA
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Donna M Ferriero
- Departments of Neurology and Pediatrics, University of California, San Francisco, CA, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Shafali S Jeste
- Departments of Neurology and Pediatrics, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Lori C Jordan
- Department of Pediatrics, Division of Pediatric Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rafael H Llinas
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bradley L Schlaggar
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Kennedy Krieger Institute, Baltimore, MD, USA
| | - Lisa R Sun
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Scott L Pomeroy
- Department of Neurology, Harvard Medical School, Boston, MA, USA
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Krainc D, Martin WJ, Casey B, Jensen FE, Tishkoff S, Potter WZ, Hyman SE. Shifting the trajectory of therapeutic development for neurological and psychiatric disorders. Sci Transl Med 2023; 15:eadg4775. [PMID: 38190501 DOI: 10.1126/scitranslmed.adg4775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 10/13/2023] [Indexed: 01/10/2024]
Abstract
Clinical trials for central nervous system disorders often enroll patients with unrecognized heterogeneous diseases, leading to costly trials that have high failure rates. Here, we discuss the potential of emerging technologies and datasets to elucidate disease mechanisms and identify biomarkers to improve patient stratification and monitoring of disease progression in clinical trials for neuropsychiatric disorders. Greater efforts must be centered on rigorously standardizing data collection and sharing of methods, datasets, and analytical tools across sectors. To address health care disparities in clinical trials, diversity of genetic ancestries and environmental exposures of research participants and associated biological samples must be prioritized.
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Affiliation(s)
- Dimitri Krainc
- Davee Department of Neurology, Simpson Querrey Center for Neurogenetics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | | | - Bradford Casey
- Michael J. Fox Foundation for Parkinson's Research, New York, NY, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarah Tishkoff
- Departments of Genetics and Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Steven E Hyman
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
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6
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Fukushima K, Higashiyama H, Kazuta Y, Hashimoto K, Watanabe N, Furuya Y, Ito Y, Wu T, Kosasa T, Talos DM, Song Y, Roberts NS, Jensen FE, Hanada T, Ido K. Discovery of E2730, a novel selective uncompetitive GAT1 inhibitor, as a candidate for anti-seizure medication. Epilepsia Open 2023; 8:834-845. [PMID: 37052238 PMCID: PMC10472371 DOI: 10.1002/epi4.12741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 04/08/2023] [Indexed: 04/14/2023] Open
Abstract
OBJECTIVE As of 2022, 36 anti-seizure medications (ASMs) have been licensed for the treatment of epilepsy, however, adverse effects (AEs) are commonly reported. Therefore, ASMs with a wide margin between therapeutic effects and AEs are preferred over ASMs that are associated with a narrow margin between efficacy and risk of AEs. E2730 was discovered using in vivo phenotypic screening and characterized as an uncompetitive, yet selective, inhibitor of γ-aminobutyric acid (GABA) transporter 1 (GAT1). Here, we describe the preclinical characteristics of E2730. METHODS Anti-seizure effects of E2730 were evaluated in several animal models of epilepsy: corneal kindling, 6 Hz-44 mA psychomotor seizure, amygdala kindling, Fragile X syndrome, and Dravet syndrome models. Effects of E2730 on motor coordination were assessed in accelerating rotarod tests. The mechanism of action of E2730 was explored by [3 H]E2730 binding assay. The GAT1-selectivity over other GABA transporters was examined by GABA uptake assay of GAT1, GAT2, GAT3, or betaine/GABA transporter 1 (BGT-1) stably expressing HEK293 cells. To further investigate the mechanism for E2730-mediated inhibition of GAT1, in vivo microdialysis and in vitro GABA uptake assays were conducted under conditions of different GABA concentrations. RESULTS E2730 showed anti-seizure effects in the assessed animal models with an approximately >20-fold margin between efficacy and motor incoordination. [3 H]E2730 binding on brain synaptosomal membrane was abolished in GAT1-deficient mice, and E2730 selectively inhibited GAT1-mediated GABA uptake over other GABA transporters. In addition, results of GABA uptake assays showed that E2730-mediated inhibition of GAT1 positively correlated to the level of ambient GABA in vitro. E2730 also increased extracellular GABA concentration in hyperactivated conditions but not under basal levels in vivo. SIGNIFICANCE E2730 is a novel, selective, uncompetitive GAT1 inhibitor, which acts selectively under the condition of increasing synaptic activity, contributing to a wide margin between therapeutic effect and motor incoordination.
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Affiliation(s)
| | | | - Yuji Kazuta
- Deep Human Biology LearningEisai Co., Ltd.TsukubaIbarakiJapan
| | | | - Naoto Watanabe
- Deep Human Biology LearningEisai Co., Ltd.TsukubaIbarakiJapan
| | - Yoshiaki Furuya
- Deep Human Biology LearningEisai Co., Ltd.TsukubaIbarakiJapan
| | - Yoshimasa Ito
- Neurology Business GroupEisai Co., Ltd.TsukubaIbarakiJapan
| | - Ting Wu
- Alzheimer's Disease and Brain HealthEisai Co., Ltd.TsukubaIbarakiJapan
| | - Takashi Kosasa
- Neurology Business GroupEisai Co., Ltd.TsukubaIbarakiJapan
| | - Delia M. Talos
- Department of Neurology, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Yeri Song
- Department of Neurology, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Nicholas S. Roberts
- Department of Neurology, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Frances E. Jensen
- Department of Neurology, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Takahisa Hanada
- Deep Human Biology LearningEisai Co., Ltd.TsukubaIbarakiJapan
| | - Katsutoshi Ido
- Neurology Business GroupEisai Co., Ltd.TsukubaIbarakiJapan
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Roberts NS, Handy MJ, Ito Y, Hashimoto K, Jensen FE, Talos DM. Anti-seizure efficacy of perampanel in two established rodent models of early-life epilepsy. Epilepsy Behav 2023; 143:109194. [PMID: 37119576 DOI: 10.1016/j.yebeh.2023.109194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/10/2023] [Accepted: 03/23/2023] [Indexed: 05/01/2023]
Abstract
Early-life seizures can be refractory to conventional antiseizure medications (ASMs) and can also result in chronic epilepsy and long-term behavioral and cognitive deficits. Treatments targeting age-specific mechanisms contributing to epilepsy would be of clinical benefit. One such target is the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subtype of excitatory glutamate receptor, which is upregulated in the developing brain. Perampanel is a non-competitive, selective AMPAR antagonist that is FDA-approved for focal onset seizures (FOS) or primary generalized tonic-clonic seizures (PGTC) in children and adults. However, the efficacy of perampanel treatment in epilepsy patients younger than 4 years has been less documented. We thus tested the efficacy of perampanel in two early-life seizure models: (1) a rat model of hypoxia-induced neonatal seizures and (2) a mouse model of Dravet syndrome with hyperthermia-induced seizures. Pretreatment with perampanel conferred dose-dependent protection against early-life seizures in both experimental models. These findings suggest that AMPAR-mediated hyperexcitability could be involved in the pathophysiology of early-life seizures, which may be amenable to treatment with perampanel.
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Affiliation(s)
- Nicholas S Roberts
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marcus J Handy
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yoshimasa Ito
- Formerly: Neurology Business Group, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Keisuke Hashimoto
- Deep Human Biology Learning, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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Brown MJ, Jensen FE, Hurtig H. In Memoriam: Arthur Knight Asbury, MD (1928-2022). Ann Neurol 2023; 93:13-14. [PMID: 36385421 DOI: 10.1002/ana.26553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 11/15/2022] [Indexed: 11/18/2022]
Affiliation(s)
- Mark J Brown
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Howard Hurtig
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Xu HN, Gourmaud S, Podsednik A, Li X, Zhao H, Jensen FE, Talos DM, Li LZ. Optical Redox Imaging of Ex Vivo Hippocampal Tissue Reveals Age-Dependent Alterations in the 5XFAD Mouse Model of Alzheimer’s Disease. Metabolites 2022; 12:metabo12090786. [PMID: 36144191 PMCID: PMC9504813 DOI: 10.3390/metabo12090786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/17/2022] [Accepted: 08/23/2022] [Indexed: 11/24/2022] Open
Abstract
A substantial decline in nicotinamide adenine dinucleotide (NAD) has been reported in brain tissue homogenates or neurons isolated from Alzheimer’s disease (AD) models. NAD, together with flavin adenine dinucleotide (FAD), critically supports energy metabolism and maintains mitochondrial redox homeostasis. Optical redox imaging (ORI) of the intrinsic fluorescence of reduced NAD (NADH) and oxidized FAD yields cellular redox and metabolic information and provides biomarkers for a variety of pathological conditions. However, its utility in AD has not been characterized at the tissue level. We performed ex vivo ORI of freshly dissected hippocampi from a well-characterized AD mouse model with five familial Alzheimer’s disease mutations (5XFAD) and wild type (WT) control littermates at various ages. We found (1) a significant increase in the redox ratio with age in the hippocampi of both the WT control and the 5XFAD model, with a more prominent redox shift in the AD hippocampi; (2) a higher NADH in the 5XFAD versus WT hippocampi at the pre-symptomatic age of 2 months; and (3) a negative correlation between NADH and Aβ42 level, a positive correlation between Fp and Aβ42 level, and a positive correlation between redox ratio and Aβ42 level in the AD hippocampi. These findings suggest that the ORI can be further optimized to conveniently study the metabolism of freshly dissected brain tissues in animal models and identify early AD biomarkers.
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Affiliation(s)
- He N. Xu
- Britton Chance Laboratory of Redox Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence: (H.N.X.); (D.M.T.); (L.Z.L.)
| | - Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Allison Podsednik
- Britton Chance Laboratory of Redox Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaofan Li
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Huaqing Zhao
- Center for Biostatistics and Epidemiology, Department of Biomedical Education and Data Science, Temple University Lewis Katz School of Medicine, Philadelphia, PA 19140, USA
| | - Frances E. Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Delia M. Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence: (H.N.X.); (D.M.T.); (L.Z.L.)
| | - Lin Z. Li
- Britton Chance Laboratory of Redox Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Correspondence: (H.N.X.); (D.M.T.); (L.Z.L.)
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10
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Gourmaud S, Stewart DA, Irwin DJ, Roberts N, Barbour AJ, Eberwine G, O’Brien WT, Vassar R, Talos DM, Jensen FE. The role of mTORC1 activation in seizure-induced exacerbation of Alzheimer's disease. Brain 2022; 145:324-339. [PMID: 34264340 PMCID: PMC9126019 DOI: 10.1093/brain/awab268] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/04/2021] [Accepted: 06/21/2021] [Indexed: 11/13/2022] Open
Abstract
The risk of seizures is 10-fold higher in patients with Alzheimer's disease than the general population, yet the mechanisms underlying this susceptibility and the effects of these seizures are poorly understood. To elucidate the proposed bidirectional relationship between Alzheimer's disease and seizures, we studied human brain samples (n = 34) from patients with Alzheimer's disease and found that those with a history of seizures (n = 14) had increased amyloid-β and tau pathology, with upregulation of the mechanistic target of rapamycin (mTOR) pathway, compared with patients without a known history of seizures (n = 20). To establish whether seizures accelerate the progression of Alzheimer's disease, we induced chronic hyperexcitability in the five times familial Alzheimer's disease mouse model by kindling with the chemoconvulsant pentylenetetrazol and observed that the mouse model exhibited more severe seizures than the wild-type. Furthermore, kindled seizures exacerbated later cognitive impairment, Alzheimer's disease neuropathology and mTOR complex 1 activation. Finally, we demonstrated that the administration of the mTOR inhibitor rapamycin following kindled seizures rescued enhanced remote and long-term memory deficits associated with earlier kindling and prevented seizure-induced increases in Alzheimer's disease neuropathology. These data demonstrated an important link between chronic hyperexcitability and progressive Alzheimer's disease pathology and suggest a mechanism whereby rapamycin may serve as an adjunct therapy to attenuate progression of the disease.
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Affiliation(s)
- Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David A Stewart
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Duke University School of Medicine, Durham, NC 27708, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nicholas Roberts
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aaron J Barbour
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Grace Eberwine
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - William T O’Brien
- Neurobehavior Testing Core, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert Vassar
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Song YJ, Xing B, Barbour AJ, Zhou C, Jensen FE. Dysregulation of GABAA Receptor-Mediated Neurotransmission during the Auditory Cortex Critical Period in the Fragile X Syndrome Mouse Model. Cereb Cortex 2021; 32:197-215. [PMID: 34223875 DOI: 10.1093/cercor/bhab203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 06/05/2021] [Accepted: 06/07/2021] [Indexed: 11/12/2022] Open
Abstract
Fragile X syndrome (FXS) is the leading monogenic form of intellectual disability and autism, with patients exhibiting numerous auditory-related phenotypes during their developmental period, including communication, language development, and auditory processing deficits. Despite FXS studies describing excitatory-inhibitory (E-I) imbalance in the auditory circuit and an impaired auditory critical period, evaluation of E-I circuitry maturation in the auditory cortex of FXS models remains limited. Here, we examined GABAA receptor (GABAAR)-mediated inhibitory synaptic transmission within the auditory cortex, characterizing normal intracortical circuit development patterns in wild-type (WT) mice and examining their dysregulation in developing Fmr1 knock-out (KO) mice. Electrophysiological recordings revealed gradual developmental shifts in WT L4-L2/3 connectivity, where circuit excitability significantly increased after critical period onset. KO mice exhibited accelerated developmental shifts related to aberrant GABAergic signaling. Specifically, Fmr1 KO L2/3 pyramidal neurons have enhanced developmental sensitivity to pharmacological GABAAR modulators, altered maturation of GABAAR voltage-dependent conductance, with additional presynaptic GABA release alterations. These differences are further accompanied by alterations in developmental long-term potentiation. Together, our results suggest that altered GABAergic signaling within developing Fmr1 KOs impairs the normal patterning of E-I circuit and synaptic plasticity maturation to contribute to the impaired auditory cortex critical period and functional auditory deficits in FXS.
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Affiliation(s)
- Yeri J Song
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Bo Xing
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aaron J Barbour
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Chengwen Zhou
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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12
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Lippman-Bell JJ, Handy M, Nieder CG, Getzfread M, Jensen FE. Altered hippocampal dendritic spine maturation after hypoxia-induced seizures in neonatal rats. Mol Cell Neurosci 2021; 113:103629. [PMID: 34015497 DOI: 10.1016/j.mcn.2021.103629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 05/10/2021] [Accepted: 05/12/2021] [Indexed: 12/01/2022] Open
Abstract
Cognitive comorbidities often follow early-life seizures (ELS), especially in the setting of autism and other neurodevelopmental syndromes. However, there is an incomplete understanding of whether neuronal and synaptic development are concomitantly dysregulated. We have previously shown that hypoxia-induced seizures (HS) in postnatal day (P)10 rats increase acute and later-life hippocampal glutamatergic neurotransmission and spontaneous recurrent seizures, and impair cognition and behavior. As dendritic spines critically regulate synaptic function, we hypothesized that ELS can induce developmentally specific changes in dendritic spine maturation. At intervals during one month following HS in P10 rats, we assessed dendritic spine development on pyramidal neurons in the stratum radiatum of hippocampal area CA1. Compared to control rats in which spine density significantly decreased from P10 to early adulthood (P38), post-seizure rats failed to show a developmental decrease in spine density, and spines from P38 post-seizure rats appeared more immature-shaped (long, thin). In addition, compared to P38 control rats, post-seizure P38 rats expressed significantly more synaptic PSD-95, a marker of mature synapses. These changes were preceded by a transient increase in hippocampal expression of cofilin phosphorylated at Ser3, representing a decrease in cofilin activity. These results suggest that early-life seizures may impair normal dendritic spine maturation and pruning in CA1 during development, resulting in an excess of less efficient synapses, via activity-dependent modification of actin-regulating proteins such as cofilin. Given that multiple neurodevelopmental disorders show similar failures in developmental spine pruning, the current findings may represent a deficit in structural plasticity that could be a component of a mechanism leading to later-life cognitive consequences associated with early-life seizures.
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Affiliation(s)
- Jocelyn J Lippman-Bell
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States of America; Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America.
| | - Marcus Handy
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Cassidy G Nieder
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States of America
| | - Mollie Getzfread
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States of America
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America.
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13
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Smith SE, Gannotti M, Hurvitz EA, Jensen FE, Krach LE, Kruer MC, Msall ME, Noritz G, Rajan DS, Aravamuthan BR. Adults with Cerebral Palsy Require Ongoing Neurologic Care: A Systematic Review. Ann Neurol 2021; 89:860-871. [PMID: 33550625 DOI: 10.1002/ana.26040] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/04/2021] [Accepted: 01/24/2021] [Indexed: 12/19/2022]
Abstract
Cerebral palsy (CP) neurologic care and research efforts typically focus on children. However, most people with CP are adults. Adults with CP are at increased risk of new neurologic conditions, such as stroke and myelopathy, that require ongoing neurologic surveillance to distinguish them from baseline motor impairments. Neurologic factors could also contribute to the motor function decline, chronic pain, and chronic fatigue that are commonly experienced by adults with CP. Based on a systematic literature review, we suggest (1) guidelines for neurologic surveillance and neurologist referral and (2) clinical research questions regarding the evolving neurologic risks for adults with CP. ANN NEUROL 2021;89:860-871.
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Affiliation(s)
- Sarah E Smith
- Washington University School of Medicine, St Louis, MO, USA
| | - Mary Gannotti
- Shriners Hospitals for Children, Cerebral Palsy Network, University of Hartford, West Hartford, CT, USA
| | - Edward A Hurvitz
- Department of Physical Medicine and Rehabilitation, Michigan Medicine/University of Michigan, Ann Arbor, MI, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Linda E Krach
- Gillette Children's Specialty Healthcare, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Michael C Kruer
- Cerebral Palsy & Pediatric Movement Disorders Program, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA.,Departments of Child Health, Neurology, and Cellular & Molecular Medicine and Program in Genetics, University of Arizona College of Medicine-Phoenix Children's Hospital, Tucson, AZ, USA
| | - Michael E Msall
- University of Chicago Kennedy Research Center on Neurodevelopmental Disabilities, Chicago, IL, USA
| | - Garey Noritz
- Department of Pediatrics, Nationwide Children's Hospital and the Ohio State University, Columbus, OH, USA
| | - Deepa S Rajan
- Department of Pediatrics, Division of Child Neurology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bhooma R Aravamuthan
- Department of Neurology, Division of Pediatric Neurology, Washington University School of Medicine, St Louis, MO, USA
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14
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Soul JS, Bergin AM, Stopp C, Hayes B, Singh A, Fortuno CR, O'Reilly D, Krishnamoorthy K, Jensen FE, Rofeberg V, Dong M, Vinks AA, Wypij D, Staley KJ. A Pilot Randomized, Controlled, Double-Blind Trial of Bumetanide to Treat Neonatal Seizures. Ann Neurol 2021; 89:327-340. [PMID: 33201535 PMCID: PMC8122513 DOI: 10.1002/ana.25959] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 01/19/2023]
Abstract
OBJECTIVE In the absence of controlled trials, treatment of neonatal seizures has changed minimally despite poor drug efficacy. We tested bumetanide added to phenobarbital to treat neonatal seizures in the first trial to include a standard-therapy control group. METHODS A randomized, double-blind, dose-escalation design was employed. Neonates with postmenstrual age 33 to 44 weeks at risk of or with seizures were eligible. Subjects with electroencephalography (EEG)-confirmed seizures after ≥20 and <40mg/kg phenobarbital were randomized to receive additional phenobarbital with either placebo (control) or 0.1, 0.2, or 0.3mg/kg bumetanide (treatment). Continuous EEG monitoring data from ≥2 hours before to ≥48 hours after study drug administration (SDA) were analyzed for seizures. RESULTS Subjects were randomized to treatment (n = 27) and control (n = 16) groups. Pharmacokinetics were highly variable among subjects and altered by hypothermia. The only statistically significant adverse event was diuresis in treated subjects (48% vs 13%, p = 0.02). One treated (4%) and 3 control subjects died (19%, p = 0.14). Among survivors, 2 of 26 treated subjects (8%) and 0 of 13 control subjects had hearing impairment, as did 1 nonrandomized subject. Total seizure burden varied widely, with much higher seizure burden in treatment versus control groups (median = 3.1 vs 1.2 min/h, p = 0.006). There was significantly greater reduction in seizure burden 0 to 4 hours and 2 to 4 hours post-SDA (both p < 0.01) compared with 2-hour baseline in treatment versus control groups with adjustment for seizure burden. INTERPRETATION Although definitive proof of efficacy awaits an appropriately powered phase 3 trial, this randomized, controlled, multicenter trial demonstrated an additional reduction in seizure burden attributable to bumetanide over phenobarbital without increased serious adverse effects. Future trials of bumetanide and other drugs should include a control group and balance seizure severity. ANN NEUROL 2021;89:327-340.
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Affiliation(s)
- Janet S Soul
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ann M Bergin
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Christian Stopp
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Breda Hayes
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Avantika Singh
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Carmen R Fortuno
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Deirdre O'Reilly
- Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kalpathy Krishnamoorthy
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Frances E Jensen
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Valerie Rofeberg
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Min Dong
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Alexander A Vinks
- Division of Clinical Pharmacology, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - David Wypij
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kevin J Staley
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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15
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Feng G, Jensen FE, Greely HT, Okano H, Treue S, Roberts AC, Fox JG, Caddick S, Poo MM, Newsome WT, Morrison JH. Opportunities and limitations of genetically modified nonhuman primate models for neuroscience research. Proc Natl Acad Sci U S A 2020; 117:24022-24031. [PMID: 32817435 PMCID: PMC7533691 DOI: 10.1073/pnas.2006515117] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The recently developed new genome-editing technologies, such as the CRISPR/Cas system, have opened the door for generating genetically modified nonhuman primate (NHP) models for basic neuroscience and brain disorders research. The complex circuit formation and experience-dependent refinement of the human brain are very difficult to model in vitro, and thus require use of in vivo whole-animal models. For many neurodevelopmental and psychiatric disorders, abnormal circuit formation and refinement might be at the center of their pathophysiology. Importantly, many of the critical circuits and regional cell populations implicated in higher human cognitive function and in many psychiatric disorders are not present in lower mammalian brains, while these analogous areas are replicated in NHP brains. Indeed, neuropsychiatric disorders represent a tremendous health and economic burden globally. The emerging field of genetically modified NHP models has the potential to transform our study of higher brain function and dramatically facilitate the development of effective treatment for human brain disorders. In this paper, we discuss the importance of developing such models, the infrastructure and training needed to maximize the impact of such models, and ethical standards required for using these models.
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Affiliation(s)
- Guoping Feng
- Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139;
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104;
| | - Henry T Greely
- Center for Law and the Biosciences, Stanford University, Stanford, CA 94305
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Shinjukuku, 160-8592 Tokyo, Japan
- Laboratory for Marmoset Neural Architecture, RIKEN Center for Brain Science, 351-0106 Saitama, Wakoshi, Japan
| | - Stefan Treue
- Cognitive Neuroscience Laboratory, German Primate Center-Leibniz Institute for Primate Research, 37077 Goettingen, Germany
- Faculty of Biology and Psychology, University of Goettingen, 37073 Goettingen, Germany
| | - Angela C Roberts
- Department of Physiology, Development, and Neuroscience, University of Cambridge, CB2 3DY Cambridge, United Kingdom
| | - James G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Sarah Caddick
- The Gatsby Charitable Foundation, SW1V 1AP London, United Kingdom
| | - Mu-Ming Poo
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 200031 Shanghai, China
| | - William T Newsome
- Wu Tsai Neurosciences Institute, Stanford University School of Medicine, Stanford, CA 94305;
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305
| | - John H Morrison
- California National Primate Research Center, University of California, Davis, CA 95616;
- Department of Neurology, School of Medicine, University of California, Davis, CA 95616
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16
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Gourmaud S, Shou H, Irwin DJ, Sansalone K, Jacobs LM, Lucas TH, Marsh ED, Davis KA, Jensen FE, Talos DM. Alzheimer-like amyloid and tau alterations associated with cognitive deficit in temporal lobe epilepsy. Brain 2020; 143:191-209. [PMID: 31834353 DOI: 10.1093/brain/awz381] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 10/08/2019] [Accepted: 10/17/2019] [Indexed: 01/27/2023] Open
Abstract
Temporal lobe epilepsy represents a major cause of drug-resistant epilepsy. Cognitive impairment is a frequent comorbidity, but the mechanisms are not fully elucidated. We hypothesized that the cognitive impairment in drug-resistant temporal lobe epilepsy could be due to perturbations of amyloid and tau signalling pathways related to activation of stress kinases, similar to those observed in Alzheimer's disease. We examined these pathways, as well as amyloid-β and tau pathologies in the hippocampus and temporal lobe cortex of drug-resistant temporal lobe epilepsy patients who underwent temporal lobe resection (n = 19), in comparison with age- and region-matched samples from neurologically normal autopsy cases (n = 22). Post-mortem temporal cortex samples from Alzheimer's disease patients (n = 9) were used as positive controls to validate many of the neurodegeneration-related antibodies. Western blot and immunohistochemical analysis of tissue from temporal lobe epilepsy cases revealed increased phosphorylation of full-length amyloid precursor protein and its associated neurotoxic cleavage product amyloid-β*56. Pathological phosphorylation of two distinct tau species was also increased in both regions, but increases in amyloid-β1-42 peptide, the main component of amyloid plaques, were restricted to the hippocampus. Furthermore, several major stress kinases involved in the development of Alzheimer's disease pathology were significantly activated in temporal lobe epilepsy brain samples, including the c-Jun N-terminal kinase and the protein kinase R-like endoplasmic reticulum kinase. In temporal lobe epilepsy cases, hippocampal levels of phosphorylated amyloid precursor protein, its pro-amyloidogenic processing enzyme beta-site amyloid precursor protein cleaving enzyme 1, and both total and hyperphosphorylated tau expression, correlated with impaired preoperative executive function. Our study suggests that neurodegenerative and stress-related processes common to those observed in Alzheimer's disease may contribute to cognitive impairment in drug-resistant temporal lobe epilepsy. In particular, we identified several stress pathways that may represent potential novel therapeutic targets.
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Affiliation(s)
- Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Haochang Shou
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Kimberly Sansalone
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Leah M Jacobs
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Timothy H Lucas
- Department of Neurosurgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Eric D Marsh
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kathryn A Davis
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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17
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Sun H, Takesian AE, Wang TT, Lippman-Bell JJ, Hensch TK, Jensen FE. Early Seizures Prematurely Unsilence Auditory Synapses to Disrupt Thalamocortical Critical Period Plasticity. Cell Rep 2019; 23:2533-2540. [PMID: 29847785 PMCID: PMC6446922 DOI: 10.1016/j.celrep.2018.04.108] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 01/02/2018] [Accepted: 04/25/2018] [Indexed: 12/31/2022] Open
Abstract
Heightened neural excitability in infancy and childhood results in increased susceptibility to seizures. Such early-life seizures are associated with language deficits and autism that can result from aberrant development of the auditory cortex. Here, we show that early-life seizures disrupt a critical period (CP) for tonotopic map plasticity in primary auditory cortex (A1). We show that this CP is characterized by a prevalence of “silent,” NMDA-receptor (NMDAR)-only, glutamate receptor synapses in auditory cortex that become “unsilenced” due to activity-dependent AMPA receptor (AMPAR) insertion. Induction of seizures prior to this CP occludes tonotopic map plasticity by prematurely unsilencing NMDAR-only synapses. Further, brief treatment with the AMPAR antagonist NBQX following seizures, prior to the CP, prevents synapse unsilencing and permits subsequent A1 plasticity. These findings reveal that early-life seizures modify CP regulators and suggest that therapeutic targets for early post-seizure treatment can rescue CP plasticity.
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Affiliation(s)
- Hongyu Sun
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Anne E Takesian
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA 02115, USA
| | - Ting Ting Wang
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Jocelyn J Lippman-Bell
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Takao K Hensch
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA 02115, USA; Center for Brain Science, Department of Molecular & Cellular Biology, Harvard University, 52 Oxford St., Cambridge, MA 02138, USA.
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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18
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Affiliation(s)
- Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia
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19
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Yennawar M, White RS, Jensen FE. AMPA Receptor Dysregulation and Therapeutic Interventions in a Mouse Model of CDKL5 Deficiency Disorder. J Neurosci 2019; 39:4814-4828. [PMID: 30952813 PMCID: PMC6561688 DOI: 10.1523/jneurosci.2041-18.2019] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 03/13/2019] [Accepted: 03/27/2019] [Indexed: 01/28/2023] Open
Abstract
Pathogenic mutations in cyclin-dependent kinase-like 5 (CDKL5) result in CDKL5 deficiency disorder (CDD), a rare disease marked by early-life seizures, autistic behaviors, and intellectual disability. Although mouse models of CDD exhibit dendritic instability and alterations in synaptic scaffolding proteins, studies of glutamate receptor levels and function are limited. Here we used a novel mouse model of CDD, the Cdkl5R59X knock-in mouse (R59X), to investigate changes in synaptic glutamate receptor subunits and functional consequences. Male mice were used for all experiments to avoid the confounding effects of X-inactivation that would be present in female heterozygous mice. We showed that adult male R59X mice recapitulated the behavioral outcomes observed in other mouse models of CDD, including social deficits and memory and learning impairments, and exhibited decreased latency to seizure upon pentylenetetrazol administration. Furthermore, we observed a specific increase in GluA2-lacking α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)-type glutamate receptors (AMPARs) in the adult R59X hippocampus, which is accompanied electrophysiologically by increased rectification ratio of AMPAR EPSCs and elevated early-phase long term potentiation (LTP). Finally, we showed that acute treatment with the GluA2-lacking AMPAR blocker IEM-1460 decreased AMPAR currents, and rescued social deficits, working memory impairments, and seizure behavior latency in R59X mice.SIGNIFICANCE STATEMENT CDKL5 deficiency disorder (CDD) is a rare disease marked by autistic-like behaviors, intellectual disability, and seizures. While synaptic dysfunction has been observed in mouse models of CDD, there is limited information on how synaptic alterations contribute to behavioral and functional changes in CDD. Here we reveal elevated hippocampal GluA2-lacking AMPAR expression in a novel mouse model of CDD that is accompanied by changes in synaptic AMPAR function and plasticity. We also show, for the first time, that acutely targeting GluA2-lacking AMPAR dysregulation rescues core synaptic and neurobehavioral deficits in CDD.
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MESH Headings
- Adult
- Animals
- Behavior, Animal
- Child, Preschool
- Disease Models, Animal
- Epileptic Syndromes/drug therapy
- Epileptic Syndromes/genetics
- Epileptic Syndromes/psychology
- Excitatory Postsynaptic Potentials/genetics
- Female
- Gene Knock-In Techniques
- Humans
- Learning Disabilities/genetics
- Learning Disabilities/psychology
- Male
- Memory Disorders/genetics
- Memory Disorders/psychology
- Mice
- Mice, Inbred C57BL
- Mice, Neurologic Mutants
- Mutation/genetics
- Protein Serine-Threonine Kinases/deficiency
- Protein Serine-Threonine Kinases/genetics
- Psychomotor Performance
- Receptors, AMPA/deficiency
- Receptors, AMPA/drug effects
- Receptors, AMPA/genetics
- Seizures/chemically induced
- Seizures/physiopathology
- Social Behavior
- Spasms, Infantile/drug therapy
- Spasms, Infantile/genetics
- Spasms, Infantile/psychology
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Affiliation(s)
| | - Rachel S White
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
| | - Frances E Jensen
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
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20
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Abstract
Seizures represent a manifestation of neurological disease in the neonatal period. Historically, neonatal seizures were identified by direct clinical observation. However, since most seizures are electroencephalographic (EEG)-only (subclinical, non-convulsive) and clinical manifestations may be subtle, many clinicians place increasing importance on EEG data including conventional EEG or amplitude-integrated EEG to identify seizures in neonates. Beyond seizure identification, the EEG is a robust source of information about brain function that can be useful for neurobehavioral prognostication in some neonates. This review summarizes the available data regarding EEG for neonatal seizure diagnosis and brain function assessment.
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Affiliation(s)
- Shavonne L Massey
- Department of Neurology and Pediatrics, Children's Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA.
| | - Frances E Jensen
- Department of Neurology and Pediatrics, Children's Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
| | - Nicholas S Abend
- Department of Neurology and Pediatrics, Children's Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
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21
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Rosenberg EC, Lippman-Bell JJ, Handy M, Soldan SS, Rakhade S, Hilario-Gomez C, Folweiler K, Jacobs L, Jensen FE. Regulation of seizure-induced MeCP2 Ser421 phosphorylation in the developing brain. Neurobiol Dis 2018; 116:120-130. [PMID: 29738885 DOI: 10.1016/j.nbd.2018.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 03/23/2018] [Accepted: 05/03/2018] [Indexed: 12/16/2022] Open
Abstract
Neonatal seizures disrupt normal synaptic maturation and often lead to later-life epilepsy and cognitive deficits. During early life, the brain exhibits heightened synaptic plasticity, in part due to a developmental overabundance of CaV1.2 L-type voltage gated calcium (Ca2+) channels (LT-VGCCs) and Ca2+-permeable AMPARs (CP-AMPARs) lacking GluA2 subunits. We hypothesized that early-life seizures overactivate these channels, in turn dysregulating Ca2+-dependent signaling pathways including that of methyl CPG binding protein 2 (MeCP2), a transcription factor implicated in the autism spectrum disorder (ASD) Rett Syndrome. Here, we show that in vivo hypoxia-induced seizures (HS) in postnatal day (P)10 rats acutely induced phosphorylation of the neuronal-specific target of activity-dependent MeCP2 phosphorylation, S421, as well as its upstream activator CaMKII T286. We next identified mechanisms by which activity-dependent Ca2+ influx induced MeCP2 phosphorylation using in vitro cortical and hippocampal neuronal cultures at embryonic day (E)18 + 10 days in vitro (DIV). In contrast to the prevalent role of NMDARs in the adult brain, we found that both CP-AMPARs and LT-VGCCs mediated MeCP2 S421 and CaMKII T286 phosphorylation induced by kainic acid (KA) or high potassium chloride (KCl) stimulation. Furthermore, in vivo post-seizure treatment with the broad-spectrum AMPAR antagonist NBQX, the CP-AMPAR blocker IEM-1460, or the LT-VGCC antagonist nimodipine blocked seizure-induced MeCP2 phosphorylation. Collectively, these results demonstrate that early-life seizures dysregulate critical activity-dependent developmental signaling pathways, in part via CP-AMPAR and LT-VGCC activation, providing novel age-specific therapeutic targets for convergent pathways underlying epilepsy and ASDs.
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Affiliation(s)
- Evan C Rosenberg
- Boston Children's Hospital, Department of Neurology, Boston, MA 02115, United States; New York University Langone Medical Center, New York, NY 10016, United States
| | - Jocelyn J Lippman-Bell
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States; Boston Children's Hospital, Department of Neurology, Boston, MA 02115, United States; Philadelphia College of Osteopathic Medicine, Department of Biomedical Sciences, Philadelphia, PA 19131, United States
| | - Marcus Handy
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States
| | - Samantha S Soldan
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States
| | - Sanjay Rakhade
- Boston Children's Hospital, Department of Neurology, Boston, MA 02115, United States
| | | | - Kaitlyn Folweiler
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States
| | - Leah Jacobs
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States
| | - Frances E Jensen
- Perelman School of Medicine, University of Pennsylvania, Department of Neurology, Philadelphia, PA 19104, United States; Boston Children's Hospital, Department of Neurology, Boston, MA 02115, United States.
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22
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Talos DM, Jacobs LM, Gourmaud S, Coto CA, Sun H, Lim KC, Lucas TH, Davis KA, Martinez-Lage M, Jensen FE. Mechanistic target of rapamycin complex 1 and 2 in human temporal lobe epilepsy. Ann Neurol 2018; 83:311-327. [PMID: 29331082 DOI: 10.1002/ana.25149] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 01/09/2018] [Accepted: 01/10/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Temporal lobe epilepsy (TLE) is a chronic epilepsy syndrome defined by seizures and progressive neurological disabilities, including cognitive impairments, anxiety, and depression. Here, human TLE specimens were investigated focusing on the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) and complex 2 (mTORC2) activities in the brain, given that both pathways may represent unique targets for treatment. METHODS Surgically resected hippocampal and temporal lobe samples from therapy-resistant TLE patients were analyzed by western blotting to quantify the expression of established mTORC1 and mTORC2 activity markers and upstream or downstream signaling pathways involving the two complexes. Histological and immunohistochemical techniques were used to assess hippocampal and neocortical structural abnormalities and cell-specific expression of individual biomarkers. Samples from patients with focal cortical dysplasia (FCD) type II served as positive controls. RESULTS We found significantly increased expression of phospho-mTOR (Ser2448), phospho-S6 (Ser235/236), phospho-S6 (Ser240/244), and phospho-Akt (Ser473) in TLE samples compared to controls, consistent with activation of both mTORC1 and mTORC2. Our work identified the phosphoinositide 3-kinase and Ras/extracellular signal-regulated kinase signaling pathways as potential mTORC1 and mTORC2 upstream activators. In addition, we found that overactive mTORC2 signaling was accompanied by induction of two protein kinase B-dependent prosurvival pathways, as evidenced by increased inhibitory phosphorylation of forkhead box class O3a (Ser253) and glycogen synthase kinase 3 beta (Ser9). INTERPRETATION Our data demonstrate that mTOR signaling is significantly dysregulated in human TLE, offering new targets for pharmacological interventions. Specifically, clinically available drugs that suppress mTORC1 without compromising mTOR2 signaling, such as rapamycin and its analogs, may represent a new group of antiepileptogenic agents in TLE patients. Ann Neurol 2018;83:311-327.
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Affiliation(s)
- Delia M Talos
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Leah M Jacobs
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Sarah Gourmaud
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Carlos A Coto
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Hongyu Sun
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA.,Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Kuei-Cheng Lim
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Timothy H Lucas
- Department of Neurosurgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Kathryn A Davis
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Maria Martinez-Lage
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| | - Frances E Jensen
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
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23
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Lechpammer M, Tran YP, Wintermark P, Martínez-Cerdeño V, Krishnan VV, Ahmed W, Berman RF, Jensen FE, Nudler E, Zagzag D. Upregulation of cystathionine β-synthase and p70S6K/S6 in neonatal hypoxic ischemic brain injury. Brain Pathol 2016; 27:449-458. [PMID: 27465493 DOI: 10.1111/bpa.12421] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/12/2016] [Indexed: 12/20/2022] Open
Abstract
Encephalopathy of prematurity (EOP) is a complex form of cerebral injury that occurs in the setting of hypoxia-ischemia (HI) in premature infants. Using a rat model of EOP, we investigated whether neonatal HI of the brain may alter the expression of cystathionine β-synthase (CBS) and the components of the mammalian target of rapamycin (mTOR) signaling. We performed unilateral carotid ligation and induced HI (UCL/HI) in Long-Evans rats at P6 and found increased CBS expression in white matter (i.e. corpus callosum, cingulum bundle and external capsule) as early as 24 h (P7) postprocedure. CBS remained elevated through P21, and, to a lesser extent, at P40. The mTOR downstream target 70 kDa ribosomal protein S6 kinase (p70S6K and phospho-p70S6K) and 40S ribosomal protein S6 (S6 and phospho-S6) were also overexpressed at the same time points in the UCL/HI rats compared to healthy controls. Overexpression of mTOR components was not observed in rats treated with the mTOR inhibitor everolimus. Behavioral assays performed on young rats (postnatal day 35-37) following UCL/HI at P6 indicated impaired preference for social novelty, a behavior relevant to autism spectrum disorder, and hyperactivity. Everolimus restored behavioral patterns to those observed in healthy controls. A gait analysis has shown that motor deficits in the hind paws of UCL/HI rats were also significantly reduced by everolimus. Our results suggest that neonatal HI brain injury may inflict long-term damage by upregulation of CBS and mTOR signaling. We propose this cascade as a possible new molecular target for EOP-a still untreatable cause of autism, hyperactivity and cerebral palsy.
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Affiliation(s)
- Mirna Lechpammer
- Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, CA
| | - Yen P Tran
- Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, CA
| | - Pia Wintermark
- Department of Pediatrics, Division of Newborn Medicine, Montréal Children's Hospital, McGill University, Montréal, QC, Canada
| | - Veronica Martínez-Cerdeño
- Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, CA.,MIND Institute, University of California Davis, Sacramento, CA.,Institute for Pediatric Regenerative Medicine and Shriners Hospital for Children of Northern California, Sacramento, CA
| | - Viswanathan V Krishnan
- Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, CA
| | - Waseem Ahmed
- Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, CA
| | - Robert F Berman
- MIND Institute, University of California Davis, Sacramento, CA.,Department of Neurological Surgery, University of California Davis, Sacramento, CA
| | - Frances E Jensen
- Department of Neurology, University of Pennsylvania, Philadelphia, PA
| | - Evgeny Nudler
- Howard Hughes Medical Institute and Department of Biochemistry, New York University School of Medicine, New York, NY
| | - David Zagzag
- Departments of Pathology and Neurosurgery, Division of Neuropathology, Microvascular and Molecular Neuro-Oncology Laboratory, Perlmutter Cancer Center, New York University Langone Medical Center, New York, NY
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24
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Lippman-Bell JJ, Zhou C, Sun H, Feske JS, Jensen FE. Early-life seizures alter synaptic calcium-permeable AMPA receptor function and plasticity. Mol Cell Neurosci 2016; 76:11-20. [PMID: 27521497 DOI: 10.1016/j.mcn.2016.08.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/15/2016] [Accepted: 08/09/2016] [Indexed: 12/31/2022] Open
Abstract
Calcium (Ca2+)-mediated4 signaling pathways are critical to synaptic plasticity. In adults, the NMDA glutamate receptor (NMDAR) represents a major route for activity-dependent synaptic Ca2+ entry. However, during neonatal development, when synaptic plasticity is particularly high, many AMPA glutamate receptors (AMPARs) are also permeable to Ca2+ (CP-AMPAR) due to low GluA2 subunit expression, providing an additional route for activity- and glutamate-dependent Ca2+ influx and subsequent signaling. Therefore, altered hippocampal Ca2+ signaling may represent an age-specific pathogenic mechanism. We thus aimed to assess Ca2+ responses 48h after hypoxia-induced neonatal seizures (HS) in postnatal day (P)10 rats, a post-seizure time point at which we previously reported LTP attenuation. We found that Ca2+ responses were higher in brain slices from post-HS rats than in controls and that this increase was CP-AMPAR-dependent. To determine whether synaptic CP-AMPAR expression was also altered post-HS, we assessed the expression of GluA2 at hippocampal synapses and the expression of long-term depression (LTD), which has been linked to the presence of synaptic GluA2. Here we report a decrease 48h after HS in synaptic GluA2 expression at synapses and LTD in hippocampal CA1. Given the potentially critical role of AMPAR trafficking in disease progression, we aimed to establish whether post-seizure in vivo AMPAR antagonist treatment prevented the enhanced Ca2+ responses, changes in GluA2 synaptic expression, and diminished LTD. We found that NBQX treatment prevents all three of these post-seizure consequences, further supporting a critical role for AMPARs as an age-specific therapeutic target.
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Affiliation(s)
- Jocelyn J Lippman-Bell
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States; Boston Children's Hospital, Boston, MA 02114, United States; Philadelphia College of Osteopathic Medicine, Philadelphia, PA 19131, United States
| | - Chengwen Zhou
- Boston Children's Hospital, Boston, MA 02114, United States
| | - Hongyu Sun
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States; Boston Children's Hospital, Boston, MA 02114, United States
| | - Joel S Feske
- Boston Children's Hospital, Boston, MA 02114, United States
| | - Frances E Jensen
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States; Boston Children's Hospital, Boston, MA 02114, United States.
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25
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Yu KJ, Kuzum D, Hwang SW, Kim BH, Juul H, Kim NH, Won SM, Chiang K, Trumpis M, Richardson AG, Cheng H, Fang H, Thomson M, Bink H, Talos D, Seo KJ, Lee HN, Kang SK, Kim JH, Lee JY, Huang Y, Jensen FE, Dichter MA, Lucas TH, Viventi J, Litt B, Rogers JA. Bioresorbable silicon electronics for transient spatiotemporal mapping of electrical activity from the cerebral cortex. Nat Mater 2016; 15:782-791. [PMID: 27088236 PMCID: PMC4919903 DOI: 10.1038/nmat4624] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/14/2016] [Indexed: 05/18/2023]
Abstract
Bioresorbable silicon electronics technology offers unprecedented opportunities to deploy advanced implantable monitoring systems that eliminate risks, cost and discomfort associated with surgical extraction. Applications include postoperative monitoring and transient physiologic recording after percutaneous or minimally invasive placement of vascular, cardiac, orthopaedic, neural or other devices. We present an embodiment of these materials in both passive and actively addressed arrays of bioresorbable silicon electrodes with multiplexing capabilities, which record in vivo electrophysiological signals from the cortical surface and the subgaleal space. The devices detect normal physiologic and epileptiform activity, both in acute and chronic recordings. Comparative studies show sensor performance comparable to standard clinical systems and reduced tissue reactivity relative to conventional clinical electrocorticography (ECoG) electrodes. This technology offers general applicability in neural interfaces, with additional potential utility in treatment of disorders where transient monitoring and modulation of physiologic function, implant integrity and tissue recovery or regeneration are required.
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Affiliation(s)
- Ki Jun Yu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Duygu Kuzum
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Electrical and Computer Engineering, University of California, San Diego, San Diego, CA 92093
| | - Suk-Won Hwang
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701, Republic of Korea
| | - Bong Hoon Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Halvor Juul
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nam Heon Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Sang Min Won
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ken Chiang
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Michael Trumpis
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Andrew G. Richardson
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Huanyu Cheng
- Department of Engineering Science and Mechanics, Penn State University, University Park, PA 16802, USA
| | - Hui Fang
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Marissa Thomson
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Chemical and Biomolecular Engineering University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Hank Bink
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Delia Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kyung Jin Seo
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hee Nam Lee
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana- Champaign, Urbana, IL 61801, USA
| | - Seung-Kyun Kang
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jae-Hwan Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jung Yup Lee
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana- Champaign, Urbana, IL 61801, USA
| | - Younggang Huang
- Department of Mechanical Engineering and Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Frances E. Jensen
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marc A. Dichter
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Timothy H. Lucas
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jonathan Viventi
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Brian Litt
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- To whom correspondence should be addressed. or
| | - John A. Rogers
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- To whom correspondence should be addressed. or
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26
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Lechpammer M, Wintermark P, Merry KM, Jackson MC, Jantzie LL, Jensen FE. Dysregulation of FMRP/mTOR Signaling Cascade in Hypoxic-Ischemic Injury of Premature Human Brain. J Child Neurol 2016; 31:426-32. [PMID: 26239490 PMCID: PMC4740274 DOI: 10.1177/0883073815596617] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 06/26/2015] [Indexed: 12/25/2022]
Abstract
In this study the authors investigated whether dysregulation of the fragile X mental retardation protein and mammalian target of rapamycin signaling cascade can have a role in the pathogenesis of encephalopathy of prematurity following perinatal hypoxia-ischemia. The authors examined the brain tissue of newborns with encephalopathy and compared it to age-matched controls with normal brain development and adults. In normal controls, the fragile X mental retardation protein expression in cortical gray matter spiked 4-fold during 36-39 gestational weeks compared to the adult, with a concomitant suppression of p70S6K and S6. In encephalopathy cases, the developmental spike of fragile X mental retardation protein was not observed, and fragile X mental retardation protein levels remained significantly lower than in normal controls. Importantly, this fragile X mental retardation protein downregulation was followed by a significant overexpression of p70S6K and S6. These novel findings thus suggest that premature hypoxic-ischemic brain injury can affect the fragile X mental retardation protein/mammalian target of rapamycin pathway, as otherwise observed in inherited syndromes of cognitive disability and autism spectrum disorders.
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Affiliation(s)
- Mirna Lechpammer
- Department of Pathology and Laboratory Medicine, University of California, Davis, Sacramento, CA, USA Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA Department of Pathology, Division of Neuropathology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Pia Wintermark
- Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA Department of Pediatrics, Division of Newborn Medicine, Montreal Children's Hospital, McGill University, Montréal, QC, Canada
| | - Katherine M Merry
- Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michele C Jackson
- Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lauren L Jantzie
- Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA Department of Pediatrics, Office of Pediatric Research, University of New Mexico, Albuquerque, NM, USA
| | - Frances E Jensen
- Department of Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
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27
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Abstract
Despite greater understanding and improved management, seizures continue to be a major problem in childhood. Neonatal seizures are often refractory to conventional antiepileptic drugs, and can result in later life epilepsy and cognitive deficits, conditions for which there are no specific treatments. Hypoxic and/or ischemic encephalopathy (HIE) is the most common cause for neonatal seizures, and accounts for more than two-thirds of neonatal seizure cases. A better understanding of the cellular and molecular mechanisms is essential for identifying new therapeutic strategies that control the neonatal seizures and its cognitive consequences. This heavily relies on animal models that play a critical role in discovering novel mechanisms underlying both epileptogenesis and associated cognitive impairments. To date, a number of animal models have provided a tremendous amount of information regarding the pathophysiology of HIE-induced neonatal seizures. This review provides an overview on the most important features of the main animal models of HIE-induced seizures. In particular, we focus on the methodology of seizure induction and the characterizations of post-HIE injury consequences. These aspects of HIE-induced seizure models are discussed in the light of the suitability of these models in studying human HIE-induced seizures.
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Affiliation(s)
- Hongyu Sun
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Halvor M Juul
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
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28
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Wintermark P, Lechpammer M, Kosaras B, Jensen FE, Warfield SK. Brain Perfusion Is Increased at Term in the White Matter of Very Preterm Newborns and Newborns with Congenital Heart Disease: Does this Reflect Activated Angiogenesis? Neuropediatrics 2015; 46:344-51. [PMID: 26340765 DOI: 10.1055/s-0035-1563533] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE This study aims to evaluate brain perfusion at term in very preterm newborns and newborns with congenital heart disease before their corrective surgery, and to search for histopathological indicators of whether the brain perfusion abnormalities of these newborns may be related to an activated angiogenesis. MATERIALS AND METHODS Using magnetic resonance imaging and arterial spin labeling, regional cerebral blood flow was measured at a term-equivalent age for three very preterm newborns (born at < 32 weeks), one newborn with congenital heart disease before his corrective surgery and three healthy newborns. In addition, a histopathological analysis was performed on a newborn with congenital heart disease. RESULTS The very preterm newborns and the newborn with congenital heart disease included in this study all displayed an increased signal in their white matter on T2-weighted imaging. The cerebral blood flow of these newborns was increased in their white matter, compared with the healthy term newborns. The vascular endothelial growth factor was overexpressed in the injured white matter of the newborn with congenital heart disease. CONCLUSION Brain perfusion may be increased at term in the white matter, in very preterm newborns, and newborns with congenital heart disease, and it correlates with white matter abnormalities on conventional imaging.
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Affiliation(s)
- Pia Wintermark
- Department of Pediatrics, McGill University, Montreal, Canada
| | - Mirna Lechpammer
- Department of Pathology, University of California Davis Medical Center, Sacramento, United States
| | - Bela Kosaras
- Department of Neurology, Boston Children's Hospital, Boston, United States
| | - Frances E Jensen
- Department of Neurology, Boston Children's Hospital, Boston, United States
| | - Simon K Warfield
- Department of Radiology, Boston Children's Hospital, Boston, United States
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29
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Zhou C, Sun H, Klein PM, Jensen FE. Neonatal seizures alter NMDA glutamate receptor GluN2A and 3A subunit expression and function in hippocampal CA1 neurons. Front Cell Neurosci 2015; 9:362. [PMID: 26441533 PMCID: PMC4585040 DOI: 10.3389/fncel.2015.00362] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/31/2015] [Indexed: 12/02/2022] Open
Abstract
Neonatal seizures are commonly caused by hypoxic and/or ischemic injury during birth and can lead to long-term epilepsy and cognitive deficits. In a rodent hypoxic seizure (HS) model, we have previously demonstrated a critical role for seizure-induced enhancement of the AMPA subtype of glutamate receptor (GluA) in epileptogenesis and cognitive consequences, in part due to GluA maturational upregulation of expression. Similarly, as the expression and function of the N-Methyl-D-aspartate (NMDA) subtype of glutamate receptor (GluN) is also developmentally controlled, we examined how early life seizures during the critical period of synaptogenesis could modify GluN development and function. In a postnatal day (P)10 rat model of neonatal seizures, we found that seizures could alter GluN2/3 subunit composition of GluNs and physiological function of synaptic GluNs. In hippocampal slices removed from rats within 48–96 h following seizures, the amplitudes of synaptic GluN-mediated evoked excitatory postsynaptic currents (eEPSCs) were elevated in CA1 pyramidal neurons. Moreover, GluN eEPSCs showed a decreased sensitivity to GluN2B selective antagonists and decreased Mg2+ sensitivity at negative holding potentials, indicating a higher proportion of GluN2A and GluN3A subunit function, respectively. These physiological findings were accompanied by a concurrent increase in GluN2A phosphorylation and GluN3A protein. These results suggest that altered GluN function and expression could potentially contribute to future epileptogenesis following neonatal seizures, and may represent potential therapeutic targets for the blockade of future epileptogenesis in the developing brain.
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Affiliation(s)
- Chengwen Zhou
- Department of Neurology, Division of Neuroscience, Boston Children's Hospital Boston, MA, USA ; Program in Neurobiology, Harvard Medical School Boston, MA, USA
| | - Hongyu Sun
- Department of Neurology, Division of Neuroscience, Boston Children's Hospital Boston, MA, USA ; Program in Neurobiology, Harvard Medical School Boston, MA, USA ; Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - Peter M Klein
- Department of Neurology, Division of Neuroscience, Boston Children's Hospital Boston, MA, USA
| | - Frances E Jensen
- Department of Neurology, Division of Neuroscience, Boston Children's Hospital Boston, MA, USA ; Program in Neurobiology, Harvard Medical School Boston, MA, USA ; Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
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30
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Abstract
Neonatal seizures are inherently different from seizures in the child and the adult. The phenotype, often exhibiting electroclinical dissociation, is unique: neonatal seizures can be refractory to antiepileptic drugs otherwise effect for older patients. Recent experimental and human-based research reveals that the mechanism of neonatal seizures, as well as their long-term sequelae on later brain development, appears to involve a large number of age-specific factors. These observations help explain the resistance of neonatal seizures to conventional therapy as well as identify potential areas of risk for later neurocognitive development. Emerging targets from this research may suggest new therapies for this unique population of patients.
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Affiliation(s)
- Frances E Jensen
- Department of Neurology, Children's Hospital, and Program in Neurobiology, Harvard Medical School, Boston, MA, USA
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31
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Dhamne SC, Ekstein D, Zhuo Z, Gersner R, Zurakowski D, Loddenkemper T, Pascual-Leone A, Jensen FE, Rotenberg A. Acute seizure suppression by transcranial direct current stimulation in rats. Ann Clin Transl Neurol 2015; 2:843-56. [PMID: 26339678 PMCID: PMC4554445 DOI: 10.1002/acn3.226] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/03/2015] [Indexed: 01/12/2023] Open
Abstract
OBJECTIVE Cathodal transcranial direct current stimulation (tDCS) is a focal neuromodulation technique that suppresses cortical excitability by low-amplitude constant electrical current, and may have an antiepileptic effect. Yet, tDCS has not been tested in status epilepticus (SE). Furthermore, a combined tDCS and pharmacotherapy antiseizure approach is unexplored. We therefore examined in the rat pentylenetetrazol (PTZ) SE model whether cathodal tDCS (1) suppresses seizures, (2) augments lorazepam (LZP) efficacy, and (3) enhances GABAergic cortical inhibition. METHODS Experiment 1 aimed to identify an effective cathodal tDCS intensity. Rats received intraperitoneal PTZ followed by tDCS (sham, cathodal 1 mA, or cathodal 0.1 mA; for 20 min), and then a second PTZ challenge. In Experiment 2, two additional animal groups received a subtherapeutic LZP dose after PTZ, and then verum or sham tDCS. Clinical and electroencephalography (EEG) epileptic activity were compared between all groups. In Experiment 3, we measured GABA-mediated paired-pulse inhibition of the motor evoked potential by paired-pulse transcranial magnetic stimulation (ppTMS) in rats that received PTZ or saline, and either verum or sham tDCS. RESULTS Cathodal 1 mA tDCS (1) reduced EEG spike bursts, and suppressed clinical seizures after the second PTZ challenge, (2) in combination with LZP was more effective in seizure suppression and improved the clinical seizure outcomes compared to either tDCS or LZP alone, and (3) prevented the loss of ppTMS motor cortex inhibition that accompanied PTZ injection. INTERPRETATION These results suggest that cathodal 1 mA tDCS alone and in combination with LZP can suppress seizures by augmenting GABAergic cortical inhibition.
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Affiliation(s)
- Sameer C Dhamne
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, and the F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA
| | - Dana Ekstein
- Department of Neurology, The Agnes Ginges Center of Human Neurogenetics, Hadassah-Hebrew University Medical Center Jerusalem, Israel
| | - Zhihong Zhuo
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, and the F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA ; Department of Pediatric Neurology, The First Affiliated Hospital of Zhengzhou University Zhengzhou, China
| | - Roman Gersner
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, and the F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA
| | - David Zurakowski
- Department of Anesthesia, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA
| | - Tobias Loddenkemper
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, and the F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School Boston, Massachusetts, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania Health System Philadelphia, Pennsylvania, USA
| | - Alexander Rotenberg
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, and the F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School Boston, Massachusetts, USA ; Department of Pediatric Neurology, The First Affiliated Hospital of Zhengzhou University Zhengzhou, China ; Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School Boston, Massachusetts, USA
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Jantzie LL, Hu MY, Park HK, Jackson MC, Yu J, Maxwell JR, Jensen FE. Chloride cotransporter NKCC1 inhibitor bumetanide protects against white matter injury in a rodent model of periventricular leukomalacia. Pediatr Res 2015; 77:554-62. [PMID: 25585037 DOI: 10.1038/pr.2015.9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/25/2014] [Indexed: 01/19/2023]
Abstract
BACKGROUND Periventricular leukomalacia (PVL) is a major form of preterm brain injury. Na(+)-K(+)-Cl(-) 1 cotransporter (NKCC1) expression on neurons and astrocytes is developmentally regulated and mediates Cl(-) reversal potential. We hypothesized that NKCC1 is highly expressed on oligodendrocytes (OLs) and increases vulnerability to hypoxia-ischemia (HI) mediated white matter injury, and that the NKCC1 inhibitor bumetanide would be protective in a rodent PVL model. METHODS Immunohistochemistry in Long-Evans rats and PLP-EGFP transgenic mice was used to establish cell-specific expression of NKCC1 in the immature rodent brain. HI was induced on postnatal day 6 (P6) in rats and the protective efficacy of bumetanide (0.3 mg/kg/i.p. q12h × 60 h) established. RESULTS NKCC1 was expressed on OLs and subplate neurons through the first 2 postnatal weeks, peaking in white matter and the subplate between P3-7. Following HI, NKCC1 is expressed on OLs and neurons. Bumetanide treatment significantly attenuates myelin basic protein loss and neuronal degeneration 7 d post-HI. CONCLUSION Presence and relative overexpression of NKCC1 in rodent cerebral cortex coincides with a period of developmental vulnerability to HI white matter injury in the immature prenatal brain. The protective efficacy of bumetanide in this model of preterm brain injury suggests that Cl(-) transport is a factor in PVL and that its inhibition may have clinical application in premature human infants.
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Affiliation(s)
- Lauren L Jantzie
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Melody Y Hu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Hyun-Kyung Park
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Michele C Jackson
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jenny Yu
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jessie R Maxwell
- Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Frances E Jensen
- 1] Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts [2] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Shaikh H, Lechpammer M, Jensen FE, Warfield SK, Hansen AH, Kosaras B, Shevell M, Wintermark P. Increased Brain Perfusion Persists over the First Month of Life in Term Asphyxiated Newborns Treated with Hypothermia: Does it Reflect Activated Angiogenesis? Transl Stroke Res 2015; 6:224-33. [PMID: 25620793 DOI: 10.1007/s12975-015-0387-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 01/06/2015] [Accepted: 01/13/2015] [Indexed: 12/23/2022]
Abstract
Many asphyxiated newborns still develop brain injury despite hypothermia therapy. The development of brain injury in these newborns has been related partly to brain perfusion abnormalities. The purposes of this study were to assess brain hyperperfusion over the first month of life in term asphyxiated newborns and to search for some histopathological clues indicating whether this hyperperfusion may be related to activated angiogenesis following asphyxia. In this prospective cohort study, regional cerebral blood flow was measured in term asphyxiated newborns treated with hypothermia around day 10 of life and around 1 month of life using magnetic resonance imaging (MRI) and arterial spin labeling. A total of 32 MRI scans were obtained from 24 term newborns. Asphyxiated newborns treated with hypothermia displayed an increased cerebral blood flow in the injured brain areas around day 10 of life and up to 1 month of life. In addition, we looked at the histopathological clues in a human asphyxiated newborn and in a rat model of neonatal encephalopathy. Vascular endothelial growth factor (VEGF) was expressed in the injured brain of an asphyxiated newborn treated with hypothermia in the first days of life and of rat pups 24-48 h after the hypoxic-ischemic event, and the endothelial cell count increased in the injured cortex of the pups 7 and 11 days after hypoxia-ischemia. Our data showed that the hyperperfusion measured by imaging persisted in the injured areas up to 1 month of life and that angiogenesis was activated in the injured brain of asphyxiated newborns.
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Affiliation(s)
- Henna Shaikh
- Department of Pediatrics, McGill University, Montreal, QC, Canada
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Simonato M, Brooks-Kayal AR, Engel J, Galanopoulou AS, Jensen FE, Moshé SL, O'Brien TJ, Pitkanen A, Wilcox KS, French JA. The challenge and promise of anti-epileptic therapy development in animal models. Lancet Neurol 2014; 13:949-60. [PMID: 25127174 PMCID: PMC5003536 DOI: 10.1016/s1474-4422(14)70076-6] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Translation of successful target and compound validation studies into clinically effective therapies is a major challenge, with potential for costly clinical trial failures. This situation holds true for the epilepsies-complex diseases with different causes and symptoms. Although the availability of predictive animal models has led to the development of effective antiseizure therapies that are routinely used in clinical practice, showing that translation can be successful, several important unmet therapeutic needs still exist. Available treatments do not fully control seizures in a third of patients with epilepsy, and produce substantial side-effects. No treatment can prevent the development of epilepsy in at-risk patients or cure patients with epilepsy. And no specific treatment for epilepsy-associated comorbidities exists. To meet these demands, a redesign of translational approaches is urgently needed.
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Affiliation(s)
- Michele Simonato
- Department of Medical Sciences (Section of Pharmacology), University of Ferrara, and National Institute of Neuroscience, Ferrara, Italy
| | - Amy R Brooks-Kayal
- Departments of Pediatrics, Neurology and Pharmaceutical Sciences, University of Colorado Schools of Medicine and Pharmacy, Children's Hospital Colorado, Aurora, CO, USA
| | - Jerome Engel
- Department of Neurology, Neurobiology, and Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Aristea S Galanopoulou
- Laboratory of Developmental Epilepsy, Montefiore/Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA; Saul R Korey Department of Neurology, Department of Dominick P Purpura Department of Neuroscience, Montefiore/Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Solomon L Moshé
- Laboratory of Developmental Epilepsy, Montefiore/Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA; Saul R Korey Department of Neurology, Department of Dominick P Purpura Department of Neuroscience, Montefiore/Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA; Department of Pediatrics, Laboratory of Developmental Epilepsy, Montefiore/Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA
| | - Terence J O'Brien
- Department of Medicine and Department of Neurology, Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia
| | - Asla Pitkanen
- Department of Neurobiology, A I Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland; Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Karen S Wilcox
- Anticonvulsant Drug Development Program, Department of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT, USA
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Obeid M, Rosenberg EC, Klein PM, Jensen FE. Lestaurtinib (CEP-701) attenuates “second hit” kainic acid-induced seizures following early life hypoxic seizures. Epilepsy Res 2014; 108:806-10. [DOI: 10.1016/j.eplepsyres.2014.01.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 10/21/2013] [Accepted: 01/06/2014] [Indexed: 11/29/2022]
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Sengupta S, Weeraratne SD, Sun H, Phallen J, Rallapalli SK, Teider N, Kosaras B, Amani V, Pierre-Francois J, Tang Y, Nguyen B, Yu F, Schubert S, Balansay B, Mathios D, Lechpammer M, Archer TC, Tran P, Reimer RJ, Cook JM, Lim M, Jensen FE, Pomeroy SL, Cho YJ. α5-GABAA receptors negatively regulate MYC-amplified medulloblastoma growth. Acta Neuropathol 2014; 127:593-603. [PMID: 24196163 DOI: 10.1007/s00401-013-1205-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 10/28/2013] [Indexed: 11/25/2022]
Abstract
Neural tumors often express neurotransmitter receptors as markers of their developmental lineage. Although these receptors have been well characterized in electrophysiological, developmental and pharmacological settings, their importance in the maintenance and progression of brain tumors and, importantly, the effect of their targeting in brain cancers remains obscure. Here, we demonstrate high levels of GABRA5, which encodes the α5-subunit of the GABAA receptor complex, in aggressive MYC-driven, "Group 3" medulloblastomas. We hypothesized that modulation of α5-GABAA receptors alters medulloblastoma cell survival and monitored biological and electrophysiological responses of GABRA5-expressing medulloblastoma cells upon pharmacological targeting of the GABAA receptor. While antagonists, inverse agonists and non-specific positive allosteric modulators had limited effects on medulloblastoma cells, a highly specific and potent α5-GABAA receptor agonist, QHii066, resulted in marked membrane depolarization and a significant decrease in cell survival. This effect was GABRA5 dependent and mediated through the induction of apoptosis as well as accumulation of cells in S and G2 phases of the cell cycle. Chemical genomic profiling of QHii066-treated medulloblastoma cells confirmed inhibition of MYC-related transcriptional activity and revealed an enrichment of HOXA5 target gene expression. siRNA-mediated knockdown of HOXA5 markedly blunted the response of medulloblastoma cells to QHii066. Furthermore, QHii066 sensitized GABRA5 positive medulloblastoma cells to radiation and chemotherapy consistent with the role of HOXA5 in directly regulating p53 expression and inducing apoptosis. Thus, our results provide novel insights into the synthetic lethal nature of α5-GABAA receptor activation in MYC-driven/Group 3 medulloblastomas and propose its targeting as a novel strategy for the management of this highly aggressive tumor.
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Affiliation(s)
- Soma Sengupta
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA
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Varadkar S, Bien CG, Kruse CA, Jensen FE, Bauer J, Pardo CA, Vincent A, Mathern GW, Cross JH. Rasmussen's encephalitis: clinical features, pathobiology, and treatment advances. Lancet Neurol 2014; 13:195-205. [PMID: 24457189 DOI: 10.1016/s1474-4422(13)70260-6] [Citation(s) in RCA: 250] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Rasmussen's encephalitis is a rare chronic neurological disorder, characterised by unilateral inflammation of the cerebral cortex, drug-resistant epilepsy, and progressive neurological and cognitive deterioration. Neuropathological and immunological studies support the notion that Rasmussen's encephalitis is probably driven by a T-cell response to one or more antigenic epitopes, with potential additional contribution by autoantibodies. Careful analysis of the association between histopathology and clinical presentation suggests that initial damage to the brain is mediated by T cells and microglia, suggesting a window for treatment if Rasmussen's encephalitis can be diagnosed early. Advances in neuroimaging suggest that progression of the inflammatory process seen with MRI might be a good biomarker in Rasmussen's encephalitis. For many patients, families, and doctors, choosing the right time to move from medical management to surgery is a real therapeutic dilemma. Cerebral hemispherectomy remains the only cure for seizures, but there are inevitable functional compromises. Decisions of whether or when surgery should be undertaken are challenging in the absence of a dense neurological deficit, and vary by institutional experience. Further, the optimum time for surgery, to give the best language and cognitive outcome, is not yet well understood. Immunomodulatory treatments seem to slow rather than halt disease progression in Rasmussen's encephalitis, without changing the eventual outcome.
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Affiliation(s)
- Sophia Varadkar
- Epilepsy Unit, Great Ormond Street Hospital for Children NHS Foundation Trust and UCL Institute of Child Health, London, UK.
| | | | - Carol A Kruse
- Department of Neurosurgery, Brain Research Institute, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - Jan Bauer
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Carlos A Pardo
- Department of Neurology and Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| | - Gary W Mathern
- Departments of Neurosurgery and Psychiatry and Biobehavioral Medicine, David Geffen School of Medicine, Mattel Children's Hospital, University of California, Los Angeles, CA, USA
| | - J Helen Cross
- Neurosciences Unit, UCL Institute of Child Health, Great Ormond Street Hospital for Children NHS Foundation Trust, London, and Young Epilepsy, Lingfield, UK
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Muller PA, Dhamne SC, Vahabzadeh-Hagh AM, Pascual-Leone A, Jensen FE, Rotenberg A. Suppression of motor cortical excitability in anesthetized rats by low frequency repetitive transcranial magnetic stimulation. PLoS One 2014; 9:e91065. [PMID: 24646791 PMCID: PMC3960125 DOI: 10.1371/journal.pone.0091065] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 02/07/2014] [Indexed: 12/24/2022] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) is a widely-used method for modulating cortical excitability in humans, by mechanisms thought to involve use-dependent synaptic plasticity. For example, when low frequency rTMS (LF rTMS) is applied over the motor cortex, in humans, it predictably leads to a suppression of the motor evoked potential (MEP), presumably reflecting long-term depression (LTD) -like mechanisms. Yet how closely such rTMS effects actually match LTD is unknown. We therefore sought to (1) reproduce cortico-spinal depression by LF rTMS in rats, (2) establish a reliable animal model for rTMS effects that may enable mechanistic studies, and (3) test whether LTD-like properties are evident in the rat LF rTMS setup. Lateralized MEPs were obtained from anesthetized Long-Evans rats. To test frequency-dependence of LF rTMS, rats underwent rTMS at one of three frequencies, 0.25, 0.5, or 1 Hz. We next tested the dependence of rTMS effects on N-methyl-D-aspartate glutamate receptor (NMDAR), by application of two NMDAR antagonists. We find that 1 Hz rTMS preferentially depresses unilateral MEP in rats, and that this LTD-like effect is blocked by NMDAR antagonists. These are the first electrophysiological data showing depression of cortical excitability following LF rTMS in rats, and the first to demonstrate dependence of this form of cortical plasticity on the NMDAR. We also note that our report is the first to show that the capacity for LTD-type cortical suppression by rTMS is present under barbiturate anesthesia, suggesting that future neuromodulatory rTMS applications under anesthesia may be considered.
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Affiliation(s)
- Paul A. Muller
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Sameer C. Dhamne
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrew M. Vahabzadeh-Hagh
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- Institut Universitari de Neurorehabilitació Guttmann, Universidad Autónoma de Barcelona, Badalona, Spain
| | - Frances E. Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania Health System, Philadelphia, Pennsylvania, United States of America
| | - Alexander Rotenberg
- Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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Brooks-Kayal AR, Bath KG, Berg AT, Galanopoulou AS, Holmes GL, Jensen FE, Kanner AM, O'Brien TJ, Whittemore VH, Winawer MR, Patel M, Scharfman HE. Authors' response to letter by A. Mazarati. Epilepsia 2013; 54:2229-30. [PMID: 24304440 DOI: 10.1111/epi.12414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amy R Brooks-Kayal
- Departments of Pediatrics, Neurology and Pharmaceutical Sciences, Children's Hospital Colorado, University of Colorado Schools of Medicine and Pharmacy, Aurora, Colorado, U.S.A.
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Wintermark P, Lechpammer M, Warfield SK, Kosaras B, Takeoka M, Poduri A, Madsen JR, Bergin AM, Whalen S, Jensen FE. Perfusion Imaging of Focal Cortical Dysplasia Using Arterial Spin Labeling: Correlation With Histopathological Vascular Density. J Child Neurol 2013; 28:1474-1482. [PMID: 23696629 PMCID: PMC5030104 DOI: 10.1177/0883073813488666] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Focal cortical dysplasia is the most common malformation of cortical development, causing intractable epilepsy. This study investigated the relationship between brain perfusion and microvessel density in 7 children with focal cortical dysplasia. The authors analyzed brain perfusion measurements obtained by magnetic resonance imaging of 2 of the children and the microvessel density of brain tissue specimens obtained by epilepsy surgery on all of the children. Brain perfusion was approximately 2 times higher in the area of focal cortical dysplasia compared to the contralateral side. The microvessel density was nearly double in the area of focal cortical dysplasia compared to the surrounding cortex that did not have morphological abnormalities. These findings suggest that hyperperfusion can be related to increased microvessel density in focal cortical dysplasia rather than only to seizures. Further investigations are needed to determine the relationship between brain perfusion, microvessel density, and seizure activity.
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Affiliation(s)
- Pia Wintermark
- Division of Newborn Medicine, Department of Pediatrics, Montreal Children’s Hospital, McGill University, Montreal, QC, Canada,Division of Newborn Medicine, Children’s Hospital Boston, Boston, MA, USA,Department of Radiology, Children’s Hospital Boston, Boston, MA, USA
| | - Mirna Lechpammer
- Department of Pathology, University of California Davis Medical Center, Sacramento, CA, USA,Department of Pathology, Children’s Hospital Boston, Boston, MA, USA,Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
| | - Simon K. Warfield
- Department of Radiology, Children’s Hospital Boston, Boston, MA, USA
| | - Bela Kosaras
- Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
| | - Masanori Takeoka
- Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
| | - Annapurna Poduri
- Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
| | - Joseph R. Madsen
- Department of Neurosurgery, Children’s Hospital Boston, Boston, MA, USA
| | - Ann M. Bergin
- Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
| | - Stephen Whalen
- Department of Radiology, Children’s Hospital Boston, Boston, MA, USA
| | - Frances E. Jensen
- Department of Neurology, Children’s Hospital Boston, Boston, MA, USA
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Pitkänen A, Nehlig A, Brooks-Kayal AR, Dudek FE, Friedman D, Galanopoulou AS, Jensen FE, Kaminski RM, Kapur J, Klitgaard H, Löscher W, Mody I, Schmidt D. Issues related to development of antiepileptogenic therapies. Epilepsia 2013; 54 Suppl 4:35-43. [PMID: 23909852 DOI: 10.1111/epi.12297] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Several preclinical proof-of-concept studies have provided evidence for positive treatment effects on epileptogenesis. However, none of these hypothetical treatments has advanced to the clinic. The experience in other fields of neurology such as stroke, Alzheimer's disease, or amyotrophic lateral sclerosis has indicated several problems in the design of preclinical studies, which likely contribute to failures in translating the positive preclinical data to the clinic. The Working Group on "Issues related to development of antiepileptogenic therapies" of the International League Against Epilepsy (ILAE) and the American Epilepsy Society (AES) has considered the possible problems that arise when moving from proof-of-concept antiepileptogenesis (AEG) studies to preclinical AEG trials, and eventually to clinical AEG trials. This article summarizes the discussions and provides recommendations on how to design a preclinical AEG monotherapy trial in adult animals. We specifically address study design, animal and model selection, number of studies needed, issues related to administration of the treatment, outcome measures, statistics, and reporting. In addition, we give recommendations for future actions to advance the preclinical AEG testing.
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Affiliation(s)
- Asla Pitkänen
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.
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Brooks-Kayal AR, Bath KG, Berg AT, Galanopoulou AS, Holmes GL, Jensen FE, Kanner AM, O'Brien TJ, Whittemore VH, Winawer MR, Patel M, Scharfman HE. Issues related to symptomatic and disease-modifying treatments affecting cognitive and neuropsychiatric comorbidities of epilepsy. Epilepsia 2013; 54 Suppl 4:44-60. [PMID: 23909853 DOI: 10.1111/epi.12298] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Many symptoms of neurologic or psychiatric illness--such as cognitive impairment, depression, anxiety, attention deficits, and migraine--occur more frequently in people with epilepsy than in the general population. These diverse comorbidities present an underappreciated problem for people with epilepsy and their caregivers because they decrease quality of life, complicate treatment, and increase mortality. In fact, it has been suggested that comorbidities can have a greater effect on quality of life in people with epilepsy than the seizures themselves. There is increasing recognition of the frequency and impact of cognitive and behavioral comorbidities of epilepsy, highlighted in the 2012 Institute of Medicine report on epilepsy. Comorbidities have also been acknowledged, as a National Institutes of Health (NIH) Benchmark area for research in epilepsy. However, relatively little progress has been made in developing new therapies directed specifically at comorbidities. On the other hand, there have been many advances in understanding underlying mechanisms. These advances have made it possible to identify novel targets for therapy and prevention. As part of the International League Against Epilepsy/American Epilepsy Society workshop on preclinical therapy development for epilepsy, our working group considered the current state of understanding related to terminology, models, and strategies for therapy development for the comorbidities of epilepsy. Herein we summarize our findings and suggest ways to accelerate development of new therapies. We also consider important issues to improve research including those related to methodology, nonpharmacologic therapies, biomarkers, and infrastructure.
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Affiliation(s)
- Amy R Brooks-Kayal
- Departments of Pediatrics, Neurology and Pharmaceutical Sciences, University of Colorado Schools of Medicine and Pharmacy, Children's Hospital Colorado, Aurora, Colorado, USA.
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Engel J, Pitkänen A, Loeb JA, Dudek FE, Bertram EH, Cole AJ, Moshé SL, Wiebe S, Jensen FE, Mody I, Nehlig A, Vezzani A. Epilepsy biomarkers. Epilepsia 2013; 54 Suppl 4:61-9. [PMID: 23909854 DOI: 10.1111/epi.12299] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A biomarker is defined as an objectively measured characteristic of a normal or pathologic biologic process. Identification and proper validation of biomarkers of epileptogenesis (the development of epilepsy) and ictogenesis (the propensity to generate spontaneous seizures) might predict the development of an epilepsy condition; identify the presence and severity of tissue capable of generating spontaneous seizures; measure progression after the condition is established; and determine pharmacoresistance. Such biomarkers could be used to create animal models for more cost-effective screening of potential antiepileptogenic and antiseizure drugs and devices, and to reduce the cost of clinical trials by enriching the trial population, and acting as surrogate markers to shorten trial duration. The objectives of the biomarker subgroup for the London Workshop were to define approaches for identifying possible biomarkers for these purposes. Research to identify reliable biomarkers may also reveal underlying mechanisms that could serve as therapeutic targets for the development of new antiepileptogenic and antiseizure compounds.
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Affiliation(s)
- Jerome Engel
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-1769, USA.
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Lippman-Bell JJ, Rakhade SN, Klein PM, Obeid M, Jackson MC, Joseph A, Jensen FE. AMPA receptor antagonist NBQX attenuates later-life epileptic seizures and autistic-like social deficits following neonatal seizures. Epilepsia 2013; 54:1922-32. [PMID: 24117347 DOI: 10.1111/epi.12378] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2013] [Indexed: 12/12/2022]
Abstract
PURPOSE To determine whether AMPA receptor (AMPAR) antagonist NBQX can prevent early mammalian target of rapamycin (mTOR) pathway activation and long-term sequelae following neonatal seizures in rats, including later-life spontaneous recurrent seizures, CA3 mossy fiber sprouting, and autistic-like social deficits. METHODS Long-Evans rats experienced hypoxia-induced neonatal seizures (HS) at postnatal day (P)10. NBQX (20 mg/kg) was administered immediately following HS (every 12 h × 4 doses). Twelve hours post-HS, we assessed mTOR activation marker phosphorylated p70-S6 kinase (p-p70S6K) in hippocampus and cortex of vehicle (HS + V) or NBQX-treated post-HS rats (HS + N) versus littermate controls (C + V). Spontaneous seizure activity was compared between groups by epidural cortical electroencephalography (EEG) at P70-100. Aberrant mossy fiber sprouting was measured using Timm staining. Finally, we assessed behavior between P30 and P38. KEY FINDINGS Postseizure NBQX treatment significantly attenuated seizure-induced increases in p-p70S6K in the hippocampus (p < 0.01) and cortex (p < 0.001). Although spontaneous recurrent seizures increased in adulthood in HS + V rats compared to controls (3.22 ± 1 seizures/h; p = 0.03), NBQX significantly attenuated later-life seizures (0.14 ± 0.1 seizures/h; p = 0.046). HS + N rats showed less aberrant mossy fiber sprouting (115 ± 8.0%) than vehicle-treated post-HS rats (174 ± 10%, p = 0.004), compared to controls (normalized to 100%). Finally, NBQX treatment prevented alterations in later-life social behavior; post-HS rats showed significantly decreased preference for a novel over a familiar rat (71.0 ± 12 s) compared to controls (99.0 ± 15.6 s; p < 0.01), whereas HS + N rats showed social novelty preference similar to controls (114.3 ± 14.1 s). SIGNIFICANCE Brief NBQX administration during the 48 h postseizure in P10 Long-Evans rats suppresses transient mTOR pathway activation and attenuates spontaneous recurrent seizures, social preference deficits, and mossy fiber sprouting observed in vehicle-treated adult rats after early life seizures. These results suggest that acute AMPAR antagonist treatment during the latent period immediately following neonatal HS can modify seizure-induced activation of mTOR, reduce the frequency of later-life seizures, and protect against CA3 mossy fiber sprouting and autistic-like social deficits.
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Affiliation(s)
- Jocelyn J Lippman-Bell
- Department of Neurology, Children's Hospital Boston and Harvard Medical School, Boston, Massachusetts, U.S.A; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A
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Jantzie LL, Talos DM, Jackson MC, Park HK, Graham DA, Lechpammer M, Folkerth RD, Volpe JJ, Jensen FE. Developmental expression of N-methyl-D-aspartate (NMDA) receptor subunits in human white and gray matter: potential mechanism of increased vulnerability in the immature brain. ACTA ACUST UNITED AC 2013; 25:482-95. [PMID: 24046081 DOI: 10.1093/cercor/bht246] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The pathophysiology of perinatal brain injury is multifactorial and involves hypoxia-ischemia (HI) and inflammation. N-methyl-d-aspartate receptors (NMDAR) are present on neurons and glia in immature rodents, and NMDAR antagonists are protective in HI models. To enhance clinical translation of rodent data, we examined protein expression of 6 NMDAR subunits in postmortem human brains without injury from 20 postconceptional weeks through adulthood and in cases of periventricular leukomalacia (PVL). We hypothesized that the developing brain is intrinsically vulnerable to excitotoxicity via maturation-specific NMDAR levels and subunit composition. In normal white matter, NR1 and NR2B levels were highest in the preterm period compared with adult. In gray matter, NR2A and NR3A expression were highest near term. NR2A was significantly elevated in PVL white matter, with reduced NR1 and NR3A in gray matter compared with uninjured controls. These data suggest increased NMDAR-mediated vulnerability during early brain development due to an overall upregulation of individual receptors subunits, in particular, the presence of highly calcium permeable NR2B-containing and magnesium-insensitive NR3A NMDARs. These data improve understanding of molecular diversity and heterogeneity of NMDAR subunit expression in human brain development and supports an intrinsic prenatal vulnerability to glutamate-mediated injury; validating NMDAR subunit-specific targeted therapies for PVL.
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Affiliation(s)
- Lauren L Jantzie
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA
| | - Delia M Talos
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA Current address: Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michele C Jackson
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA
| | - Hyun-Kyung Park
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA
| | - Dionne A Graham
- Harvard Medical School, Boston, MA 02115, USA Clinical Research Center
| | - Mirna Lechpammer
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA Department of Pathology (Neuropathology), Boston Children's Hospital, Boston, MA 02115, USA
| | - Rebecca D Folkerth
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA Department of Pathology (Neuropathology), Boston Children's Hospital, Boston, MA 02115, USA
| | - Joseph J Volpe
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA
| | - Frances E Jensen
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA Harvard Medical School, Boston, MA 02115, USA Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA Current address: Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Jensen FE, Paulson HL, Bar-Or A. Considering a career in neurology research? Heed these words. Ann Neurol 2013; 74:A12. [DOI: 10.1002/ana.24008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Cleary RT, Sun H, Huynh T, Manning SM, Li Y, Rotenberg A, Talos DM, Kahle KT, Jackson M, Rakhade SN, Berry G, Jensen FE. Bumetanide enhances phenobarbital efficacy in a rat model of hypoxic neonatal seizures. PLoS One 2013; 8:e57148. [PMID: 23536761 PMCID: PMC3594228 DOI: 10.1371/journal.pone.0057148] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 01/17/2013] [Indexed: 01/30/2023] Open
Abstract
Neonatal seizures can be refractory to conventional anticonvulsants, and this may in part be due to a developmental increase in expression of the neuronal Na(+)-K(+)-2 Cl(-) cotransporter, NKCC1, and consequent paradoxical excitatory actions of GABAA receptors in the perinatal period. The most common cause of neonatal seizures is hypoxic encephalopathy, and here we show in an established model of neonatal hypoxia-induced seizures that the NKCC1 inhibitor, bumetanide, in combination with phenobarbital is significantly more effective than phenobarbital alone. A sensitive mass spectrometry assay revealed that bumetanide concentrations in serum and brain were dose-dependent, and the expression of NKCC1 protein transiently increased in cortex and hippocampus after hypoxic seizures. Importantly, the low doses of phenobarbital and bumetanide used in the study did not increase constitutive apoptosis, alone or in combination. Perforated patch clamp recordings from ex vivo hippocampal slices removed following seizures revealed that phenobarbital and bumetanide largely reversed seizure-induced changes in EGABA. Taken together, these data provide preclinical support for clinical trials of bumetanide in human neonates at risk for hypoxic encephalopathy and seizures.
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Affiliation(s)
- Ryan T. Cleary
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Hongyu Sun
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Thanhthao Huynh
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Simon M. Manning
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
- Division of Newborn Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - Yijun Li
- Division of Genetics and Metabolism, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Alexander Rotenberg
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Delia M. Talos
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Kristopher T. Kahle
- Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michele Jackson
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Sanjay N. Rakhade
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Gerard Berry
- Division of Genetics and Metabolism, Children’s Hospital Boston, Boston, Massachusetts, United States of America
| | - Frances E. Jensen
- Department of Neurology, Children’s Hospital Boston, Boston, Massachusetts, United States of America
- Program in Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America
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Fernández IS, Chapman KE, Peters JM, Kothare SV, Nordli DR, Jensen FE, Berg AT, Loddenkemper T. The tower of Babel: survey on concepts and terminology in electrical status epilepticus in sleep and continuous spikes and waves during sleep in North America. Epilepsia 2012; 54:741-50. [PMID: 23163318 DOI: 10.1111/epi.12039] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The terms "electrical status epilepticus during sleep (ESES)" and "continuous spikes and waves during sleep (CSWS)" have been used interchangeably when referring to related but different concepts. In addition, the quantification of epileptiform activity has not been standardized, and different approaches to quantification have been used. The aim of this study was to evaluate the extent to which pediatric neurologists and epileptologists use a homogeneous terminology and conceptualization in CSWS and ESES and to characterize the current understanding of these conditions. METHODS A survey addressing the use of terminology in "ESES" and "CSWS" and the understanding of related concepts was distributed online to all members of the Child Neurology Society and the American Epilepsy Society mailing lists. Surveys were self-administered and collected using an online survey website (http://www.surveymonkey.com). KEY FINDINGS Two hundred nineteen surveys were completed, 137 from the Child Neurology Society mailing list and 82 from the American Epilepsy Society mailing list. ESES and CSWS were considered synonymous by 117 respondents, not synonymous by 61, 21 respondents did not know, and 20 did not respond. Most respondents (63.1%) considered CSWS as a devastating epileptic encephalopathy with severe sequelae even if treated correctly, but 25.1% of respondents indicated that it does not leave sequelae if epilepsy was treated early and another 11.8% noted that cognitive difficulties resolved with age. Cognitive and/or language regression were considered mandatory for the diagnosis of CSWS by only 27% of the respondents. The diagnosis of CSWS was based on electroencephalography (EEG) assessment alone by 31% of respondents. Respondents used different methods for calculation of the epileptiform activity, different EEG samples for calculation, and considered differently the lateralized epileptiform activity. The cut-off values for percentage of the sleep record occupied by spike-waves were variable depending on the respondent. There was no agreement on whether these cutoff values were mandatory for the diagnosis of ESES and CSWS. SIGNIFICANCE Our data show that the professionals caring for children with ESES and CSWS in North America use the terms, concepts, and defining features heterogeneously. The lack of a common language may complicate communication among clinicians and jeopardize research in this field. We anticipate that our data will fuel the development of much needed common terminology and conceptualization of ESES and CSWS.
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Affiliation(s)
- Iván Sánchez Fernández
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Talos DM, Sun H, Kosaras B, Joseph A, Folkerth RD, Poduri A, Madsen JR, Black PM, Jensen FE. Altered inhibition in tuberous sclerosis and type IIb cortical dysplasia. Ann Neurol 2012; 71:539-51. [PMID: 22447678 PMCID: PMC3334406 DOI: 10.1002/ana.22696] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Revised: 11/17/2011] [Accepted: 12/09/2011] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The most common neurological symptom of tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) is early life refractory epilepsy. As previous studies have shown enhanced excitatory glutamatergic neurotransmission in TSC and FCD brains, we hypothesized that neurons associated with these lesions may also express altered γ-aminobutyric acid (GABA)(A) receptor (GABA(A)R)-mediated inhibition. METHODS Expression of the GABA(A)R subunits α1 and α4, and the Na(+)-K(+)-2Cl(-) (NKCC1) and the K(+)-Cl(-) (KCC2) transporters, in human TSC and FCD type II specimens were analyzed by Western blot and double label immunocytochemistry. GABA(A) R responses in dysplastic neurons from a single case of TSC were measured by perforated patch recording and compared to normal-appearing cortical neurons from a non-TSC epilepsy case. RESULTS TSC and FCD type IIb lesions demonstrated decreased expression of GABA(A)R α1, and increased NKCC1 and decreased KCC2 levels. In contrast, FCD type IIa lesions showed decreased α4, and increased expression of both NKCC1 and KCC2 transporters. Patch clamp recordings from dysplastic neurons in acute slices from TSC tubers demonstrated excitatory GABA(A)R responses that were significantly attenuated by the NKCC1 inhibitor bumetanide, in contrast to hyperpolarizing GABA(A)R-mediated currents in normal neurons from non-TSC cortical slices. INTERPRETATION Expression and function of GABA(A)Rs in TSC and FCD type IIb suggest the relative benzodiazepine insensitivity and more excitatory action of GABA compared to FCD type IIa. These factors may contribute to resistance of seizure activity to anticonvulsants that increase GABAergic function, and may justify add-on trials of the NKCC1 inhibitor bumetanide for the treatment of TSC and FCD type IIb-related epilepsy.
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Affiliation(s)
- Delia M. Talos
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Hongyu Sun
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Bela Kosaras
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | | | - Rebecca D. Folkerth
- Department of Pathology (Neuropathology), Children’s Hospital Boston
- Department of Pathology, Brigham and Women’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Annapurna Poduri
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Joseph R. Madsen
- Department of Neurosurgery, Children’s Hospital Boston
- Department of Neurosurgery, Brigham and Women’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Peter M. Black
- Department of Neurosurgery, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
| | - Frances E. Jensen
- Department of Neurology, Children’s Hospital Boston
- Harvard Medical School, Boston, Massachusetts 02115
- Program in Neuroscience, Boston, Massachusetts 02115
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Kabakov AY, Muller PA, Pascual-Leone A, Jensen FE, Rotenberg A. Contribution of axonal orientation to pathway-dependent modulation of excitatory transmission by direct current stimulation in isolated rat hippocampus. J Neurophysiol 2012; 107:1881-9. [PMID: 22219028 DOI: 10.1152/jn.00715.2011] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a method for modulating cortical excitability by weak constant electrical current that is applied through scalp electrodes. Although often described in terms of anodal or cathodal stimulation, depending on which scalp electrode pole is proximal to the cortical region of interest, it is the orientation of neuronal structures relative to the direct current (DC) vector that determines the effect of tDCS. To investigate the contribution of neural pathway orientation, we studied DCS-mediated neuromodulation in an in vitro rat hippocampal slice preparation. We examined the contribution of dendritic orientation to the direct current stimulation (DCS) neuromodulatory effect by recording field excitatory postsynaptic potentials (fEPSPs) in apical and basal dendrites of CA1 neurons within a constant DC field. In addition, we assessed the contribution of axonal orientation by recording CA1 and CA3 apical fEPSPs generated by stimulation of oppositely oriented Schaffer collateral and mossy fiber axons, respectively, during DCS. Finally, nonsynaptic excitatory signal propagation was measured along antidromically stimulated CA1 axons at different DCS amplitudes and polarity. We find that modulation of both the fEPSP and population spike depends on axonal orientation relative to the electric field vector. Axonal orientation determines whether the DC field is excitatory or inhibitory and dendritic orientation affects the magnitude, but not the overall direction, of the DC effect. These data suggest that tDCS may oppositely affect neurons in a stimulated cortical volume if these neurons are excited by oppositely orientated axons in a constant electrical field.
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Affiliation(s)
- Anatoli Y Kabakov
- Department of Neurology, Children's Hospital Boston, 300 Longwood Ave., Boston, MA 02115, USA
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