1
|
Ruggiero RN, Marques DB, Rossignoli MT, De Ross JB, Prizon T, Beraldo IJS, Bueno-Junior LS, Kandratavicius L, Peixoto-Santos JE, Lopes-Aguiar C, Leite JP. Dysfunctional hippocampal-prefrontal network underlies a multidimensional neuropsychiatric phenotype following early-life seizure. eLife 2024; 12:RP90997. [PMID: 38593008 PMCID: PMC11003745 DOI: 10.7554/elife.90997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024] Open
Abstract
Brain disturbances during development can have a lasting impact on neural function and behavior. Seizures during this critical period are linked to significant long-term consequences such as neurodevelopmental disorders, cognitive impairments, and psychiatric symptoms, resulting in a complex spectrum of multimorbidity. The hippocampus-prefrontal cortex (HPC-PFC) circuit emerges as a potential common link between such disorders. However, the mechanisms underlying these outcomes and how they relate to specific behavioral alterations are unclear. We hypothesized that specific dysfunctions of hippocampal-cortical communication due to early-life seizure would be associated with distinct behavioral alterations observed in adulthood. Here, we performed a multilevel study to investigate behavioral, electrophysiological, histopathological, and neurochemical long-term consequences of early-life Status epilepticus in male rats. We show that adult animals submitted to early-life seizure (ELS) present working memory impairments and sensorimotor disturbances, such as hyperlocomotion, poor sensorimotor gating, and sensitivity to psychostimulants despite not exhibiting neuronal loss. Surprisingly, cognitive deficits were linked to an aberrant increase in the HPC-PFC long-term potentiation (LTP) in a U-shaped manner, while sensorimotor alterations were associated with heightened neuroinflammation, as verified by glial fibrillary acidic protein (GFAP) expression, and altered dopamine neurotransmission. Furthermore, ELS rats displayed impaired HPC-PFC theta-gamma coordination and an abnormal brain state during active behavior resembling rapid eye movement (REM) sleep oscillatory dynamics. Our results point to impaired HPC-PFC functional connectivity as a possible pathophysiological mechanism by which ELS can cause cognitive deficits and psychiatric-like manifestations even without neuronal loss, bearing translational implications for understanding the spectrum of multidimensional developmental disorders linked to early-life seizures.
Collapse
Affiliation(s)
- Rafael Naime Ruggiero
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| | - Danilo Benette Marques
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| | - Matheus Teixeira Rossignoli
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| | - Jana Batista De Ross
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| | - Tamiris Prizon
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| | - Ikaro Jesus Silva Beraldo
- Department of Physiology and Biophysics Federal University of Minas GeraisBelo HorizonteBrazil
- Laboratory of Molecular and Behavioral Neuroscience (LANEC), Federal University of Minas GeraisBelo HorizonteBrazil
| | | | | | - Jose Eduardo Peixoto-Santos
- Neuroscience Discipline, Department of Neurology and Neurosurgery,Universidade Federal de São PauloSão PauloBrazil
| | - Cleiton Lopes-Aguiar
- Department of Physiology and Biophysics Federal University of Minas GeraisBelo HorizonteBrazil
- Laboratory of Molecular and Behavioral Neuroscience (LANEC), Federal University of Minas GeraisBelo HorizonteBrazil
| | - Joao Pereira Leite
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão PretoBrazil
| |
Collapse
|
2
|
Kiselev A, Kotov A, Mikhaleva M, Stovbun S, Kotov S. Ampakines — a promising approach to neuroprotection. Zh Nevrol Psikhiatr Im S S Korsakova 2022; 122:54-62. [DOI: 10.17116/jnevro202212209154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
3
|
Zaitsev АV, Amakhin DV, Dyomina AV, Zakharova MV, Ergina JL, Postnikova TY, Diespirov GP, Magazanik LG. Synaptic Dysfunction in Epilepsy. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s002209302103008x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
4
|
Kaminiów K, Kozak S, Paprocka J. Neonatal Seizures Revisited. CHILDREN-BASEL 2021; 8:children8020155. [PMID: 33670692 PMCID: PMC7922511 DOI: 10.3390/children8020155] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/02/2021] [Accepted: 02/12/2021] [Indexed: 12/29/2022]
Abstract
Seizures are the most common neurological disorder in newborns and are most prevalent in the neonatal period. They are mostly caused by severe disorders of the central nervous system (CNS). However, they can also be a sign of the immaturity of the infant’s brain, which is characterized by the presence of specific factors that increase excitation and reduce inhibition. The most common disorders which result in acute brain damage and can manifest as seizures in neonates include hypoxic-ischemic encephalopathy (HIE), ischemic stroke, intracranial hemorrhage, infections of the CNS as well as electrolyte and biochemical disturbances. The therapeutic management of neonates and the prognosis are different depending on the etiology of the disorders that cause seizures which can lead to death or disability. Therefore, establishing a prompt diagnosis and implementing appropriate treatment are significant, as they can limit adverse long-term effects and improve outcomes. In this review paper, we present the latest reports on the etiology, pathomechanism, clinical symptoms and guidelines for the management of neonates with acute symptomatic seizures.
Collapse
Affiliation(s)
- Konrad Kaminiów
- Students’ Scientific Society, Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland; (K.K.); (S.K.)
| | - Sylwia Kozak
- Students’ Scientific Society, Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland; (K.K.); (S.K.)
| | - Justyna Paprocka
- Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
- Correspondence:
| |
Collapse
|
5
|
Luo X, Yu X, Liang J, Sun R, Li C, Jiang J. Involvement of GluA1-AMPAR-mediated LTP in time-dependent decline of cognitive function in rats with temporal lobe epilepsy. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-020-00036-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Cognitive impairment is one of the common comorbidities in patients with temporal lobe epilepsy (TLE), but the underlying mechanisms remain largely unknown. Previous studies have found significant decay of hippocampal long-term potentiation (LTP) in TLE rats with cognitive impairment. As the activation of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) is responsible for LTP formation and learning and memory, we investigated whether AMPARs are involved in the LTP inhibition and the TLE-associated cognitive impairments.
Methods
TLE rat model was established by intraperitoneal injection of lithium chloride-pilocarpine on postnatal day 21 (P21). Learning and memory performance, hippocampal expression of membrane GluA1-AMPARs, and hippocampal LTP were tested by behavioral tests, western blotting, and field potential recording, respectively, at 1, 5 and 13 weeks after induction of status epilepticu (SE). Finally, the effects of (S)-AMPA, an agonist of AMPARs, on LTP and cognitive function were tested.
Results
Results of behavioral tests revealed an time-dependent decline in the learning and memory of TLE rats when compared to the age-matched controls at week 5 and 13, rather than at week 1 after the induction of SE. Western blotting showed that the hippocampal expression of membrane GluA1 was significantly decreased in a time-dependent manner in the TLE rats when compared to the age-matched controls at weeks 5 and 13, rather than at week 1 after the induction of SE. Similarly, the hippocampal LTP was inhibited in a time-dependent manner in TLE rats at weeks 5 and 13, rather than at week 1 after the induction of SE. Moreover, intra-hippocampal injection of (S)-AMPA ameliorated the deficits in learning as well as spatial and emotional memory in a dose-dependent manner, and partially reversed the inhibition of CA1 LTP in the TLE rats at week 13 after the induction of SE.
Conclusions
The reduced expression of hippocampal membrane GluA1 may be involved in LTP decay in CA1 and cognition impairment in TLE rats.
Collapse
|
6
|
Pisani F, Fusco C, Spagnoli C. Linking acute symptomatic neonatal seizures, brain injury and outcome in preterm infants. Epilepsy Behav 2020; 112:107406. [PMID: 32889509 DOI: 10.1016/j.yebeh.2020.107406] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/06/2020] [Accepted: 08/09/2020] [Indexed: 11/29/2022]
Abstract
Neonatal seizures (NS) are the most frequent sign of neurological dysfunction in newborn infants. With increased survival of preterm neonates, the current clinical focus has shifted from preventing death to improving long-term neurological outcome. In the context of acute symptomatic NS, the main negative prognostic factors include etiology, and severity of brain injury, but also prolonged seizures and especially status epilepticus. However, the reasons for the detrimental contribution of seizures to outcome are still unclear, and evidence has been collected both in favor of seizures being an epiphenomenon of brain injury and of independently contributing to further damage. In this narrative focused review, we will discuss both hypotheses, with special emphasis on data relating to preterm infants. We will also identify present controversies and possible future lines of research.
Collapse
Affiliation(s)
- Francesco Pisani
- Child Neuropsychiatric Unit, Medicine & Surgery Department, Neuroscience Section, University of Parma, Italy.
| | - Carlo Fusco
- Department of Pediatrics, Child Neurology Unit, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy.
| | - Carlotta Spagnoli
- Department of Pediatrics, Child Neurology Unit, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy.
| |
Collapse
|
7
|
Postnikova TY, Amakhin DV, Trofimova AM, Zaitsev AV. Calcium-permeable AMPA receptors are essential to the synaptic plasticity induced by epileptiform activity in rat hippocampal slices. Biochem Biophys Res Commun 2020; 529:1145-1150. [PMID: 32819578 DOI: 10.1016/j.bbrc.2020.06.121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 06/24/2020] [Indexed: 10/23/2022]
Abstract
Abnormal neuronal activity during epileptic seizures alters the properties of synaptic plasticity, and, consequently, leads to cognitive impairment. The molecular mechanism of these alterations in synaptic plasticity is still unclear. In the present study, using a 4-aminopyridine (4-AP) in vitro model, we demonstrated that epileptiform activity in rat hippocampal slices initially causes substantial enhancement of field excitatory postsynaptic potential amplitude. However, the potentiation of CA3-CA1 synapses was temporary and switched to long-term depression (LTD) within an hour. Previous studies showed that transient incorporation of calcium-permeable AMPA receptors (CP-AMPARs) is crucial for the consolidation of long-term potentiation (LTP). We confirmed that, in normal conditions, the blockage of CP-AMPARs prevented the consolidation of LTP induced by theta-burst stimulation (TBS). In contrast, the blockage of CP-AMPARs preserved synaptic potentiation induced by epileptiform activity. One hour after a period of epileptiform activity in the hippocampal slices, synaptic plasticity was substantially altered, and the TBS protocol was unable to produce LTP. Moreover, if CP-AMPARs were blocked, the TBS protocol induced LTD. Our results indicate that CP-AMPARs play an essential role in the molecular mechanism of the disturbances of synaptic plasticity caused by epileptiform activity.
Collapse
Affiliation(s)
- Tatyana Y Postnikova
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS, 44, Toreza Prospekt, Saint Petersburg, 194223, Russia
| | - Dmitry V Amakhin
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS, 44, Toreza Prospekt, Saint Petersburg, 194223, Russia
| | - Alina M Trofimova
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS, 44, Toreza Prospekt, Saint Petersburg, 194223, Russia
| | - Aleksey V Zaitsev
- Sechenov Institute of Evolutionary Physiology and Biochemistry of RAS, 44, Toreza Prospekt, Saint Petersburg, 194223, Russia.
| |
Collapse
|
8
|
Synaptic GluN2A-Containing NMDA Receptors: From Physiology to Pathological Synaptic Plasticity. Int J Mol Sci 2020; 21:ijms21041538. [PMID: 32102377 PMCID: PMC7073220 DOI: 10.3390/ijms21041538] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 12/16/2022] Open
Abstract
N-Methyl-d-Aspartate Receptors (NMDARs) are ionotropic glutamate-gated receptors. NMDARs are tetramers composed by several homologous subunits of GluN1-, GluN2-, or GluN3-type, leading to the existence in the central nervous system of a high variety of receptor subtypes with different pharmacological and signaling properties. NMDAR subunit composition is strictly regulated during development and by activity-dependent synaptic plasticity. Given the differences between GluN2 regulatory subunits of NMDAR in several functions, here we will focus on the synaptic pool of NMDARs containing the GluN2A subunit, addressing its role in both physiology and pathological synaptic plasticity as well as the contribution in these events of different types of GluN2A-interacting proteins.
Collapse
|
9
|
O'Leary H, Vanderlinden L, Southard L, Castano A, Saba LM, Benke TA. Transcriptome analysis of rat dorsal hippocampal CA1 after an early life seizure induced by kainic acid. Epilepsy Res 2020; 161:106283. [PMID: 32062370 DOI: 10.1016/j.eplepsyres.2020.106283] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/17/2020] [Accepted: 01/29/2020] [Indexed: 12/13/2022]
Abstract
Seizures that occur during early development are associated with adverse neurodevelopmental outcomes. Causation and mechanisms are currently under investigation. Induction of an early life seizure by kainic acid (KA) in immature rats on post-natal day (P) 7 results in behavioral changes in the adult rat that reflect social and intellectual deficits without overt cellular damage. Our previous work also demonstrated increased expression of CA1 hippocampal long-term potentiation (LTP) and reduced desensitization of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type ionotropic glutamate receptors (AMPA-R) one week following a kainic acid induced seizure (KA-ELS). Here we used RNA sequencing (RNAseq) of mRNA from dorsal hippocampal CA1 to probe changes in mRNA levels one week following KA-ELS as a means to investigate the mechanisms for these functional changes. Ingenuity pathway analysis (IPA) confirmed our previous results by predicting an up-regulation of the synaptic LTP pathway. Differential gene expression results revealed significant differences in 7 gene isoforms. Additional assessments included AMPA-R splice variants and adenosine deaminase acting on RNA 2 (ADAR2) editing sites as a means to determine the mechanism for reduced AMPA-R desensitization. Splice variant analysis demonstrated that KA-ELS result in a small, but significant decrease in the "flop" isoform of Gria3, and editing site analysis revealed significant changes in the editing of a kainate receptor subunit, Grik2, and a serotonin receptor, Htr2c. While these specific changes may not account for altered AMPA-R desensitization, the differences indicate that KA-ELS alters gene expression in the hippocampal CA1 one week after the insult.
Collapse
Affiliation(s)
- Heather O'Leary
- Department of Pediatrics, University of Colorado, School of Medicine, 80045, United States.
| | - Lauren Vanderlinden
- Department of Biostatistics and Informatics, Colorado School of Public Health, 80045, United States.
| | - Lara Southard
- Department of Psychology, Colorado State University, Fort Collins, 80523, United States.
| | - Anna Castano
- Department of Pediatrics, University of Colorado, School of Medicine, 80045, United States.
| | - Laura M Saba
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, 80045, United States.
| | - Tim A Benke
- Department of Pediatrics, University of Colorado, School of Medicine, 80045, United States; Department of Neurology, University of Colorado, School of Medicine, 80045, United States; Department of Pharmacology, University of Colorado, School of Medicine, 80045, United States; Department of Otolaryngology, University of Colorado, School of Medicine, 80045, United States; Neuroscience Graduate Program, University of Colorado, School of Medicine, 80045, United States.
| |
Collapse
|
10
|
Lamani M, Malamas MS, Farah SI, Shukla VG, Almeida MF, Weerts CM, Anderson J, Wood JT, Farizatto KLG, Bahr BA, Makriyannis A. Piperidine and piperazine inhibitors of fatty acid amide hydrolase targeting excitotoxic pathology. Bioorg Med Chem 2019; 27:115096. [PMID: 31629610 DOI: 10.1016/j.bmc.2019.115096] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/07/2019] [Accepted: 09/08/2019] [Indexed: 11/30/2022]
Abstract
FAAH inhibitors offer safety advantages by augmenting the anandamide levels "on demand" to promote neuroprotective mechanisms without the adverse psychotropic effects usually seen with direct and chronic activation of the CB1 receptor. FAAH is an enzyme implicated in the hydrolysis of the endocannabinoid N-arachidonoylethanolamine (AEA), which is a partial agonist of the CB1 receptor. Herein, we report the discovery of a new series of highly potent and selective carbamate FAAH inhibitors and their evaluation for neuroprotection. The new inhibitors showed potent nanomolar inhibitory activity against human recombinant and purified rat FAAH, were selective (>1000-fold) against serine hydrolases MGL and ABHD6 and lacked any affinity for the cannabinoid receptors CB1 and CB2. Evaluation of FAAH inhibitors 9 and 31 using the in vitro competitive activity-based protein profiling (ABPP) assay confirmed that both inhibitors were highly selective for FAAH in the brain, since none of the other FP-reactive serine hydrolases in this tissue were inhibited by these agents. Our design strategy followed a traditional SAR approach and was supported by molecular modeling studies based on known FAAH cocrystal structures. To rationally design new molecules that are irreversibly bound to FAAH, we have constructed "precovalent" FAAH-ligand complexes to identify good binding geometries of the ligands within the binding pocket of FAAH and then calculated covalent docking poses to select compounds for synthesis. FAAH inhibitors 9 and 31 were evaluated for neuroprotection in rat hippocampal slice cultures. In the brain tissue, both inhibitors displayed protection against synaptic deterioration produced by kainic acid-induced excitotoxicity. Thus, the resultant compounds produced through rational design are providing early leads for developing therapeutics against seizure-related damage associated with a variety of disorders.
Collapse
Affiliation(s)
- Manjunath Lamani
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - Michael S Malamas
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA.
| | - Shrouq I Farah
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - Vidyanand G Shukla
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - Michael F Almeida
- Biotechnology Research and Training Center, University of North Carolina-Pembroke, Pembroke, NC 28372, USA
| | - Catherine M Weerts
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - Joseph Anderson
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - JodiAnne T Wood
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| | - Karen L G Farizatto
- Biotechnology Research and Training Center, University of North Carolina-Pembroke, Pembroke, NC 28372, USA
| | - Ben A Bahr
- Biotechnology Research and Training Center, University of North Carolina-Pembroke, Pembroke, NC 28372, USA
| | - Alexandros Makriyannis
- Center for Drug Discovery and Department of Chemistry and Chemical Biology and Pharmaceutical Sciences, Northeastern University, Boston, MA 02155, USA
| |
Collapse
|
11
|
Carrasco M, Stafstrom CE. How Early Can a Seizure Happen? Pathophysiological Considerations of Extremely Premature Infant Brain Development. Dev Neurosci 2019; 40:417-436. [PMID: 30947192 DOI: 10.1159/000497471] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 02/04/2019] [Indexed: 11/19/2022] Open
Abstract
Seizures in neonates represent a neurologic emergency requiring prompt recognition, determination of etiology, and treatment. Yet, the definition and identification of neonatal seizures remain challenging and controversial, in part due to the unique physiology of brain development at this life stage. These issues are compounded when considering seizures in premature infants, in whom the complexities of brain development may engender different clinical and electrographic seizure features at different points in neuronal maturation. In extremely premature infants (< 28 weeks gestational age), seizure pathophysiology has not been explored in detail. This review discusses the physiological and structural development of the brain in this developmental window, focusing on factors that may lead to seizures and their consequences at this early time point. We hypothesize that the clinical and electrographic phenomenology of seizures in extremely preterm infants reflects the specific pathophysiology of brain development in that age window.
Collapse
Affiliation(s)
- Melisa Carrasco
- Division of Pediatric Neurology, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA,
| |
Collapse
|
12
|
Histone deacetylase inhibitors restore normal hippocampal synaptic plasticity and seizure threshold in a mouse model of Tuberous Sclerosis Complex. Sci Rep 2019; 9:5266. [PMID: 30918308 PMCID: PMC6437206 DOI: 10.1038/s41598-019-41744-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 03/15/2019] [Indexed: 01/02/2023] Open
Abstract
Abnormal synaptic plasticity has been implicated in several neurological disorders including epilepsy, dementia and Autism Spectrum Disorder (ASD). Tuberous Sclerosis Complex (TSC) is an autosomal dominant genetic disorder that manifests with seizures, autism, and cognitive deficits. The abnormal intracellular signaling underlying TSC has been the focus of many studies. However, nothing is known about the role of histone modifications in contributing to the neurological manifestations in TSC. Dynamic regulation of chromatin structure via post translational modification of histone tails has been implicated in learning, memory and synaptic plasticity. Histone acetylation and associated gene activation plays a key role in plasticity and so we asked whether histone acetylation might be dysregulated in TSC. In this study, we report a general reduction in hippocampal histone H3 acetylation levels in a mouse model of TSC2. Pharmacological inhibition of Histone Deacetylase (HDAC) activity restores histone H3 acetylation levels and ameliorates the aberrant plasticity in TSC2+/− mice. We describe a novel seizure phenotype in TSC2+/− mice that is also normalized with HDAC inhibitors (HDACis). The results from this study suggest an unanticipated role for chromatin modification in TSC and may inform novel therapeutic strategies for TSC patients.
Collapse
|
13
|
Wu XQ, Zhao YN, Ding J, Si Z, Cheng DF, Shi HC, Wang X. Decreased vesicular acetylcholine transporter related to memory deficits in epilepsy: A [ 18 F] VAT positron emission tomography brain imaging study. Epilepsia 2018; 59:1655-1666. [PMID: 30126014 DOI: 10.1111/epi.14533] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 07/18/2018] [Accepted: 07/18/2018] [Indexed: 01/22/2023]
Abstract
OBJECTIVE Vesicular acetylcholine transporter (VAChT) is a rate-limiting factor for synaptic acetylcholine transport. Our study focused on whether [18 F] VAT, a novel positron emission tomography (PET) tracer, could be used in detecting cognitive deficits in epilepsy. METHODS Morris water maze test was used to evaluate learning and memory deficits in pilocarpine-induced chronic epilepsy rats 12 weeks after status epilepticus. Interictal [18 F] VAT PET was performed 13 weeks after status epilepticus to evaluate the level of VAChT in cholinergic pathways compared with [18 F] fluorodeoxyglucose PET. The association between VAChT levels and memory measures was analyzed. Neuropathological tests were performed. RESULTS Epileptic rats exhibited significant memory deficits in Morris water maze test. [18 F] VAT uptake decreased in septum, hippocampus, thalamus, and basal forebrain, and correlated to memory function. Of note, the level of VAChT in basal forebrain significantly decreased, yet no glucose hypometabolism was detected. Immunofluorescence and Western blot demonstrated decreased expression of VAChT in hippocampus and basal forebrain in the epilepsy group, but no change of expression of acetyltransferase or activity of acetylcholinesterase was detected. SIGNIFICANCE [18 F] VAT PET is a promising method to test the level of VAChT as a valuable biomarker for memory deficits in pilocarpine-induced chronic epileptic rats.
Collapse
Affiliation(s)
- Xu-Qing Wu
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Ya-Nan Zhao
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jing Ding
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Zhan Si
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Deng-Feng Cheng
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hong-Cheng Shi
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xin Wang
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, Institute of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, China
| |
Collapse
|
14
|
Analysis of the CaMKIIα and β splice-variant distribution among brain regions reveals isoform-specific differences in holoenzyme formation. Sci Rep 2018; 8:5448. [PMID: 29615706 PMCID: PMC5882894 DOI: 10.1038/s41598-018-23779-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/20/2018] [Indexed: 12/21/2022] Open
Abstract
Four CaMKII isoforms are encoded by distinct genes, and alternative splicing within the variable linker-region generates additional diversity. The α and β isoforms are largely brain-specific, where they mediate synaptic functions underlying learning, memory and cognition. Here, we determined the α and β splice-variant distribution among different mouse brain regions. Surprisingly, the nuclear variant αB was detected in all regions, and even dominated in hypothalamus and brain stem. For CaMKIIβ, the full-length variant dominated in most regions (with higher amounts of minor variants again seen in hypothalamus and brain stem). The mammalian but not fish CaMKIIβ gene lacks exon v3N that encodes the nuclear localization signal in αB, but contains three exons not found in the CaMKIIα gene (exons v1, v4, v5). While skipping of exons v1 and/or v5 generated the minor splice-variants β’, βe and βe’, essentially all transcripts contained exon v4. However, we instead detected another minor splice-variant (now termed βH), which lacks part of the hub domain that mediates formation of CaMKII holoenzymes. Surprisingly, in an optogenetic cellular assay of protein interactions, CaMKIIβH was impaired for binding to the β hub domain, but still bound CaMKIIα. This provides the first indication for isoform-specific differences in holoenzyme formation.
Collapse
|
15
|
Postnikova TY, Zubareva OE, Kovalenko AA, Kim KK, Magazanik LG, Zaitsev AV. Status epilepticus impairs synaptic plasticity in rat hippocampus and is followed by changes in expression of NMDA receptors. BIOCHEMISTRY (MOSCOW) 2017; 82:282-290. [DOI: 10.1134/s0006297917030063] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|