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Hajipour S, Khombi Shooshtari M, Farbood Y, Ali Mard S, Sarkaki A, Moradi Chameh H, Sistani Karampour N, Ghafouri S. Fingolimod administration following hypoxia induced neonatal seizure can restore impaired long-term potentiation and memory performance in adult rats. Neuroscience 2023; 519:107-119. [PMID: 36990271 DOI: 10.1016/j.neuroscience.2023.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/18/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Neonatal seizures commonly caused by hypoxia can lead to long-term neurological outcomes. Early inflammation plays an important role in the pathology of these outcomes. Therefore, in the current study, we explored the long-term effects of Fingolimod (FTY720), an analog of sphingosine and potentsphingosine 1-phosphate(S1P) receptors modulator, as an anti-inflammatory and neuroprotective agent in attenuating anxiety, memory impairment, and possible alterations in gene expression of hippocampal inhibitory and excitatory receptors following hypoxia-induced neonatal seizure (HINS). Seizure was induced in 24 male and female pups (6 in each experimental group) at postnatal day 10 (P10) by premixed gas (5% oxygen/ 95% nitrogen) in a hypoxic chamber for 15 minutes. Sixty minutes after the onset of hypoxia, FTY720 (0.3 mg/kg) or saline (100 µl) was administered for 12 days (from P10 up to P21). Anxiety-like behavior and hippocampal memory function were assessed at P90 by elevated plus maze (EPM) and novel object recognition (NOR), respectively. Long-term potentiation (LTP) was recorded from hippocampal dentate gyrus region (DG) following stimulation of perforant pathway (PP). In addition, the hippocampal concentration of superoxide dismutase activity (SOD), malondialdehyde (MDA), and thiol as indices of oxidative stress were evaluated. Finally, the gene expression of NR2A subunit of N-Methyl-D-aspartic acid (NMDA) receptor, GluR2 subunit of (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) AMPA receptor and γ2 subunit of γ-Aminobutyric acid (GABAA) receptor were assessed at P90 by the quantitative real-time PCR. FTY720 significantly reduced later-life anxiety-like behavior, ameliorated object recognition memory and increased the amplitude and slope of the field excitatory postsynaptic potential (fEPSP) in the rats following HINS. These effects were associated with restoration of the hippocampal thiol content to the normal values and the regulatory role of FTY720 in the expression of hippocampal GABA and glutamate receptors subunits. In conclusion, FTY720 could restore the dysregulated gene expression of excitatory and inhibitory receptors. It also increased the reduced hippocampal thiol content, which was accompanied with attenuation of HINS-induced anxiety, reduced the impaired hippocampal related memory, and prevented hippocampal LTP deficits in later life following HINS.
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Pazarlar BA, Madsen CA, Oyar EÖ, Eğilmez CB, Mikkelsen JD. Temporal and Spatial Changes in Synaptic Vesicle Glycoprotein 2 A (SV2A) under Kainic Acid Induced Epileptogenesis: An Autoradiographic Study. Epilepsy Res 2022; 183:106926. [DOI: 10.1016/j.eplepsyres.2022.106926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 04/10/2022] [Accepted: 04/14/2022] [Indexed: 11/03/2022]
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Trollmann R. Neuromonitoring bei zerebralen Anfällen im Neugeborenenalter – Chancen und Herausforderungen. KLIN NEUROPHYSIOL 2021. [DOI: 10.1055/a-1438-1828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Angesichts der vielen Kinder mit neonatalen Risikofaktoren für erworbene ZNS-Läsionen und zerebrale Anfälle ist das EEG zunehmend relevant für eine optimierte Diagnostik und Therapieüberwachung 1
2. Folgender Artikel gibt einen Überblick über Besonderheiten des neonatalen EEG und über aktuelle Empfehlungen zum Stellenwert des Langzeit-EEG-Monitorings bei neonatalen Anfällen und epileptischen Enzephalopathien im Früh- und Neugeborenalter.
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Trollmann R. Neuromonitoring in Neonatal-Onset Epileptic Encephalopathies. Front Neurol 2021; 12:623625. [PMID: 33603712 PMCID: PMC7884638 DOI: 10.3389/fneur.2021.623625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/12/2021] [Indexed: 12/31/2022] Open
Abstract
Considering the wide spectrum of etiologies of neonatal-onset epileptic encephalopathies (EE) and their unfavorable consequences for neurodevelopmental prognoses, neuromonitoring at-risk neonates is increasingly important. EEG is highly sensitive for early identification of electrographic seizures and abnormal background activity. Amplitude-integrated EEG (aEEG) is recommended as a useful bedside monitoring method but as a complementary tool because of methodical limitations. It is of special significance in monitoring neonates with acute symptomatic as well as structural, metabolic and genetic neonatal-onset EE, being at high risk of electrographic-only and prolonged seizures. EEG/aEEG monitoring is established as an adjunctive tool to confirm perinatal hypoxic-ischemic encephalopathy (HIE). In neonates with HIE undergoing therapeutic hypothermia, burst suppression pattern is associated with good outcomes in about 40% of the patients. The prognostic specificity of EEG/aEEG is lower compared to cMRI. As infants with HIE may develop seizures after cessation of hypothermia, recording for at least 24 h after the last seizure is recommended. Progress in the identification of genetic etiology of neonatal EE constantly increases. However, presently, no specific EEG changes indicative of a genetic variant have been characterized, except for individual variants associated with typical EEG patterns (e.g., KCNQ2, KCNT1). Long-term monitoring studies are necessary to define and classify electro-clinical patterns of neonatal-onset EE.
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Affiliation(s)
- Regina Trollmann
- Department of Pediatrics and Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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5
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Menéndez Méndez A, Smith J, Engel T. Neonatal Seizures and Purinergic Signalling. Int J Mol Sci 2020; 21:ijms21217832. [PMID: 33105750 PMCID: PMC7660091 DOI: 10.3390/ijms21217832] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 02/07/2023] Open
Abstract
Neonatal seizures are one of the most common comorbidities of neonatal encephalopathy, with seizures aggravating acute injury and clinical outcomes. Current treatment can control early life seizures; however, a high level of pharmacoresistance remains among infants, with increasing evidence suggesting current anti-seizure medication potentiating brain damage. This emphasises the need to develop safer therapeutic strategies with a different mechanism of action. The purinergic system, characterised by the use of adenosine triphosphate and its metabolites as signalling molecules, consists of the membrane-bound P1 and P2 purinoreceptors and proteins to modulate extracellular purine nucleotides and nucleoside levels. Targeting this system is proving successful at treating many disorders and diseases of the central nervous system, including epilepsy. Mounting evidence demonstrates that drugs targeting the purinergic system provide both convulsive and anticonvulsive effects. With components of the purinergic signalling system being widely expressed during brain development, emerging evidence suggests that purinergic signalling contributes to neonatal seizures. In this review, we first provide an overview on neonatal seizure pathology and purinergic signalling during brain development. We then describe in detail recent evidence demonstrating a role for purinergic signalling during neonatal seizures and discuss possible purine-based avenues for seizure suppression in neonates.
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Affiliation(s)
- Aida Menéndez Méndez
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; (A.M.M.); (J.S.)
| | - Jonathon Smith
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; (A.M.M.); (J.S.)
- FutureNeuro, Science Foundation Ireland Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
| | - Tobias Engel
- Department of Physiology and Medical Physics, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; (A.M.M.); (J.S.)
- FutureNeuro, Science Foundation Ireland Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, Dublin D02 YN77, Ireland
- Correspondence: ; Tel.: +35-314-025-199
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6
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Sadeghian A, Salari Z, Azizi H, Raoufy MR, Shojaei A, Kosarmadar N, Zare M, Rezaei M, Barkley V, Javan M, Fathollahi Y, Mirnajafi-Zadeh J. The role of dopamine D 2-like receptors in a "depotentiation-like effect" of deep brain stimulation in kindled rats. Brain Res 2020; 1738:146820. [PMID: 32251663 DOI: 10.1016/j.brainres.2020.146820] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/31/2020] [Accepted: 04/02/2020] [Indexed: 01/12/2023]
Abstract
The mechanisms involved in the anti-seizure effects of low-frequency stimulation (LFS) have not been completely determined. However, Gi-protein-coupled receptors, including D2-like receptors, may have a role in mediating these effects. In the present study, the role of D2-like receptors in LFS' anti-seizure action was investigated. Rats were kindled with semi-rapid (6 stimulations per day), electrical stimulation of the hippocampal CA1 area. In LFS-treated groups, subjects received four trials of LFS at 5 min, 6 h, 24 h, and 30 h following the last kindling stimulation. Each LFS set occurred at 5 min intervals, and consisted of 4 trains. Each train contained 200, 0/1 ms long, monophasic square wave pulses at 1 Hz. Haloperidol (D2-like receptors antagonist, 2 µm) and/or bromocriptine (D2-like receptors agonist 2 µg/µlit) were microinjected into the lateral ventricle immediately after the last kindling, before applying LFS. Obtained results showed that applying LFS in fully-kindled subjects led to a depotentiation-like decrease in kindling-induced potentiation and reduced the amplitude and rise slope of excitatory and inhibitory post-synaptic currents in whole-cell recordings from CA1 pyramidal neurons. In addition, LFS restored the kindling-induced, spatial learning and memory impairments in the Barnes maze test. A D2-like receptor antagonist inhibited these effects of LFS, while a D2-like receptor agonist mimicked these effects. In conclusion, a depotentiation-like mechanism may be involved in restoring LFS' effects on learning and memory, and synaptic plasticity. These effects depend on D2-like receptors activity.
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Affiliation(s)
- Azam Sadeghian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Zahra Salari
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hossein Azizi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Reza Raoufy
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Amir Shojaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Nastaran Kosarmadar
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Meysam Zare
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mahmoud Rezaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Victoria Barkley
- Krembil Research Institute, University Health Network, Toronto, Canada
| | - Mohammad Javan
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Institute for Brain Sciences and Cognition, Tarbiat Modares University, Tehran, Iran.
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7
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Jung S, Ballheimer YE, Brackmann F, Zoglauer D, Geppert CI, Hartmann A, Trollmann R. Seizure-induced neuronal apoptosis is related to dysregulation of the RNA-edited GluR2 subunit in the developing mouse brain. Brain Res 2020; 1735:146760. [PMID: 32142720 DOI: 10.1016/j.brainres.2020.146760] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 02/27/2020] [Accepted: 03/02/2020] [Indexed: 12/28/2022]
Abstract
Ca2+-permeable AMPA receptors (AMPAR) which crucially modify maturational programs of the developing brain are involved in seizure-induced glutamate excitotoxicity and apoptosis. Regulatory effects on AMPAR subunit composition and RNA-editing in the developing brain and their significance as therapeutic targets are not well understood. Here, we analyzed acute effects of recurrent pilocarpine-induced neonatal seizures on age- and region-specific expression of AMPAR subunits and adenosine deaminases (ADAR) in the developing mouse brain (P10). After recurrent seizure activity and regeneration periods of 6-72 h cerebral mRNA levels of GluR (glutamate receptor subunit) 1, GluR2, GluR3, and GluR4 were unaffected compared to controls. However, ratio of GluR2 and GluR4 to pooled GluR1-4 mRNA concentration significantly decreased in seizure-exposed brains in comparison to controls. After a regeneration period of 24-72 h ADAR1 and ADAR2 mRNA expression was significantly lower in seizure-exposed brains than in those of controls. This was confirmed at the protein level in the hippocampal CA3 region. We observed a regionally increased apoptosis (TUNEL+ and CC3+ cells) in the hippocampus, parietal cortex and subventricular zone of seizure-exposed brains in comparison to controls. Together, present in vivo data demonstrate the maturational age-specific, functional role of RNA-edited GluR2 in seizure-induced excitotoxicity in the developing mouse brain. In response to recurrent seizure activity, we observed reduced expression of GluR2 and the GluR2 mRNA-editing enzymes ADAR1 and ADAR2 accompanied by increased apoptosis in a region-specific manner. Thus, AMPA receptor subtype-specific mRNA editing is assessed as a promising target of novel neuroprotective treatment strategies in consideration of age-related developmental mechanisms.
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Affiliation(s)
- Susan Jung
- Department of Pediatrics, Division of Neuropediatrics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Yili E Ballheimer
- Department of Pediatrics, Division of Neuropediatrics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Florian Brackmann
- Department of Pediatrics, Division of Neuropediatrics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel Zoglauer
- Department of Pediatrics, Division of Neuropediatrics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Carol-Immanuel Geppert
- Institute of Pathology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Arndt Hartmann
- Institute of Pathology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Regina Trollmann
- Department of Pediatrics, Division of Neuropediatrics, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
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8
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Neonatal Neurocritical Care: Providing Brain-Focused Care for All at Risk Neonates. Semin Pediatr Neurol 2019; 32:100774. [PMID: 31813520 DOI: 10.1016/j.spen.2019.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neonatal neurocritical care is an evolving subsubspecialty whose goal is to implement neuroprotective care strategies, continuous bedside monitoring of neurologic function, and therapies in order to reduce the risk of neurologic injury and improve long-term neurodevelopmental outcomes in neonates who require intensive care. The provision of neonatal neurocritical care requires a culture change across a Neonatal Intensive Care Unit (NICU) in which equal importance is placed on the neurologic care and the cardiorespiratory care of a given patient. It is a multidisciplinary framework of care in which neonatologist and pediatric neurologist come together to address the unique needs of NICU patients whose brains are still developing and are vulnerable to injury. Advances in bedside brain monitoring techniques and the use of therapeutic hypothermia for Hupoxic-Ischemic Encephalopathy have accelerated the development of NeuroNICUs across the United States and abroad. Neonatologists, neurologists, neurophysiologists, nurses, and other ancillary members of the team work together to develop guidelines for commonly encountered neurological conditions in the NICU. The use of these guidelines helps provide standardized care across a unit and can reduce morbidity and length of hospital stay.
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9
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Cheng Y, Mai Q, Zeng X, Wang H, Xiao Y, Tang L, Li J, Zhang Y, Ding H. Propionate relieves pentylenetetrazol-induced seizures, consequent mitochondrial disruption, neuron necrosis and neurological deficits in mice. Biochem Pharmacol 2019; 169:113607. [PMID: 31491413 DOI: 10.1016/j.bcp.2019.08.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 08/13/2019] [Indexed: 12/18/2022]
Abstract
The present research was designed to evaluate the protective effects and underlying mechanisms of propionate, a bioactive food additive, on mitochondrial disruption, neuron necrosis and neurological deficits after epilepsy seizures. Epilepsy seizures was induced by repetitive injections of pentylenetetrazol at a dose of 37 mg per kg. Propionate (37.5, 50 and 75 mg/kg) as well as sodium valproate (300 mg/kg) were administrated intragastrically (i.g.) 1 h before each PTZ injection and continued for 40 days. The influence of propionate was assessed by many biochemical assays and neurobehavioral experiments. The results of gas chromatography (GC) analysis indicated that increased concentration of propionate can be explored in hippocampus area of propionate + PTZ treated animals. Propionate decreased epilepsy seizure intensity, increased latency of seizures. Meanwhile, propionate treatment reversed the structure disruption of the mitochondria, improved ATP level and lessened 8-OHdG level in the brains of animals with seizures. In addition, we find propionate pretreated can increase activities of the antioxidant enzymes (CAT, SOD, as well as GSH-Px) in mitochondria. Additionally, propionate reduced neuronal loss in hippocampus and our results suggest that HIF-1α/ERK pathway and neuron necrosis exists potential linkage during epileptogenesis. Moreover, as a result, propionate administration can significantly improve the neurological function estimated by a battery of functional tests. In conclusion, treatment with propionate attenuates mitochondrial disruption, hippocampal apoptosis and neurological deficits in a mouse model of epilepsy seizures. Therefore, propionate, currently used as a food preservative, has a potential additional advantage of ameliorating epilepsy seizures.
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Affiliation(s)
- Yahong Cheng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Qianting Mai
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Xin Zeng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Huiling Wang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Yao Xiao
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Liu Tang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Jing Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Yiyuan Zhang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Hong Ding
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei, PR China.
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10
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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] [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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11
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Zhang X, Qu H, Wang Y, Zhao S, Xiao T, Zhao C, Teng W. Aberrant plasticity in the hippocampus after neonatal seizures. Int J Neurosci 2017; 128:384-391. [PMID: 28937832 DOI: 10.1080/00207454.2017.1384380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Xiaoqian Zhang
- Department of Neurology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Huiling Qu
- Department of Neurology, The People's Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Ying Wang
- Department of Neurology, The First Hospital of Dalian Medical University, Dalian, Liaoning, PR China
| | - Shanshan Zhao
- Department of Neurology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Ting Xiao
- Department of Dermatology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
- Key Laboratory of Immunodermatology, Ministry of Health, Ministry of Education, Shenyang, Liaoning, PR China
| | - Chuansheng Zhao
- Department of Neurology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
| | - Weiyu Teng
- Department of Neurology, The First Hospital of China Medical University, Shenyang, Liaoning, PR China
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12
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Stafstrom CE, Staedtke V, Comi AM. Epilepsy Mechanisms in Neurocutaneous Disorders: Tuberous Sclerosis Complex, Neurofibromatosis Type 1, and Sturge-Weber Syndrome. Front Neurol 2017; 8:87. [PMID: 28367137 PMCID: PMC5355446 DOI: 10.3389/fneur.2017.00087] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/24/2017] [Indexed: 01/27/2023] Open
Abstract
Neurocutaneous disorders are multisystem diseases affecting skin, brain, and other organs. Epilepsy is very common in the neurocutaneous disorders, affecting up to 90% of patients with tuberous sclerosis complex (TSC) and Sturge–Weber syndrome (SWS), for example. The mechanisms underlying the increased predisposition to brain hyperexcitability differ between disorders, yet some molecular pathways overlap. For instance, the mechanistic target of rapamycin (mTOR) signaling cascade plays a central role in seizures and epileptogenesis in numerous acquired and genetic disorders, including several neurocutaneous disorders. Potential routes for target-specific treatments are emerging as the genetic and molecular pathways involved in neurocutaneous disorders become increasingly understood. This review explores the clinical features and mechanisms of epilepsy in three common neurocutaneous disorders—TSC, neurofibromatosis type 1, and SWS.
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Affiliation(s)
- Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Verena Staedtke
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Anne M Comi
- Department of Neurology, Kennedy Krieger Institute, Johns Hopkins University School of Medicine , Baltimore, MD , USA
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13
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Barry JM, Holmes GL. Why Are Children With Epileptic Encephalopathies Encephalopathic? J Child Neurol 2016; 31:1495-1504. [PMID: 27515946 PMCID: PMC5410364 DOI: 10.1177/0883073816662140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 05/24/2016] [Indexed: 12/16/2022]
Abstract
The epileptic encephalopathies are devastating conditions characterized by frequent seizures, severely abnormal electroencephalograms (EEGs), and cognitive slowing or regression. The cognitive impairment in the epileptic encephalopathies may be more concerning to the patient and parents than the epilepsy itself. There is increasing recognition that the cognitive comorbidity can be both chronic, primarily due to the underlying etiology of the epilepsy, and dynamic or evolving because of recurrent seizures, interictal spikes, and antiepileptic drugs. Much of scholars' understanding of the neurophysiological underpinnings of cognitive dysfunction in the epileptic encephalopathies comes from rodent studies. Frequent seizures and interictal EEG discharges in rats lead to considerable spatial and social-cognitive deficits. Paralleling these cognitive deficits are dyscoordination of dynamic neural activity within and between the neural networks that subserve normal cognitive processes.
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Affiliation(s)
- Jeremy M Barry
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA
| | - Gregory L Holmes
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA
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Han T, Qin Y, Mou C, Wang M, Jiang M, Liu B. Seizure induced synaptic plasticity alteration in hippocampus is mediated by IL-1β receptor through PI3K/Akt pathway. Am J Transl Res 2016; 8:4499-4509. [PMID: 27830035 PMCID: PMC5095344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 10/02/2016] [Indexed: 06/06/2023]
Abstract
Seizures, which result from synchronized aberrant firing of neuronal populations, can cause long-term sequelae, such as epilepsy, cognitive and behavioral issues, in which the synaptic plasticity alteration may play an important role. Long-term potentiation (LTP) is a persistent increase in synaptic strength and is essential for learning and memory. In the present study, we first examined the alteration of cognitive impairments and synaptic plasticity in mice with seizures, then explored the underlying mechanism involving pro-inflammatory factors and PI3K/Akt pathway. The results demonstrated that: (1) PTZ-induced seizure impairs learning and memory in mice, indicated by Morris water maze test; (2) PTZ-induced seizure decreased LTP; (3) the mRNA expression of IL-1β, IL-6 and TNF-α in the hippocampus were increased in mice with seizures; (4) LTP was increased by IL-1β receptor antagonist anakinra, but not inhibitors of IL-6 or TNF-α receptor; (5) Antagonist of IL-1β receptor rescues deficits in learning and memory of mice with seizures through PI3K/Akt pathway. It is concluded that the IL-1β induced by PTZ-induced seizures may impair the synaptic plasticity alteration in hippocampus as well as learning and memory ability by PI3K/Akt signaling pathway.
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Affiliation(s)
- Tao Han
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
| | - Yanyu Qin
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
| | - Chenzhi Mou
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
| | - Min Wang
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
| | - Meng Jiang
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
| | - Bin Liu
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University 9677 Jingshi Road, Jinan, Shandong 250021, China
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Abstract
Epilepsy is a complex disorder, which involves much more than seizures, encompassing a range of associated comorbid health conditions that can have significant health and quality-of-life implications. Of these comorbidities, cognitive impairment is one of the most common and distressing aspects of epilepsy. Clinical studies have demonstrated that refractory seizures, resistant to antiepileptic drugs, and occurring early in life have significant adverse effects on cognitive function. Much of what has been learned about the neurobiological underpinnings of cognitive impairment following early-life seizures has come from animal models. Although early-life seizures in rodents do not result in cell loss, seizures cause in changes in neurogenesis and synaptogenesis and alteration of excitatory or inhibitory balance, network connectivity and temporal coding. These morphological and physiological changes are accompanied by parallel impairment in cognitive skills. This increased understanding of the pathophysiological basis of seizure-induced cognitive deficits should allow investigators to develop novel targets for therapeutic interventions.
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Affiliation(s)
- Gregory L Holmes
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT.
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Abstract
The challenges to individuals with epilepsy extend far beyond the seizures. Co-morbidities in epilepsy are very common and are often more problematic to individuals than the seizures themselves. In this review, the pathophysiological mechanisms of cognitive impairment are discussed. While aetiology of the epilepsy has a significant influence on cognition, there is increasing evidence that prolonged or recurrent seizures can cause or exacerbate cognitive impairment. Alterations in signalling pathways and neuronal network function play a major role in both the pathophysiology of epilepsy and the epilepsy comorbidities. However, the biological underpinnings of cognitive impairment can be distinct from the pathophysiological processes that cause seizures.
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Shellhaas RA. Continuous long-term electroencephalography: the gold standard for neonatal seizure diagnosis. Semin Fetal Neonatal Med 2015; 20:149-53. [PMID: 25660396 DOI: 10.1016/j.siny.2015.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Newborn infants at risk for cerebral dysfunction, such as those with acute brain injury or with disorders of brain development, often have encephalopathy and seizures. Conventional electroencephalography (EEG) monitoring can enhance the care of these highly vulnerable patients, through identification of prognostically significant EEG background patterns and accurate diagnosis of seizures and non-seizure paroxysmal events. Neonatal seizures are usually subclinical, and abnormal neonatal movements are often not the result of seizures. Judicious use of conventional EEG monitoring can provide precise diagnosis, quantify seizures, and guide treatment--neonates with EEG-proven seizures should receive appropriate medications and those whose events are not seizures may be spared unnecessary exposure to medications that have potentially important side-effects.
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Affiliation(s)
- Renée A Shellhaas
- Department, Division of Pediatric Neurology, C.S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI, USA.
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Holmes GL, Tian C, Hernan AE, Flynn S, Camp D, Barry J. Alterations in sociability and functional brain connectivity caused by early-life seizures are prevented by bumetanide. Neurobiol Dis 2015; 77:204-19. [PMID: 25766676 PMCID: PMC4682568 DOI: 10.1016/j.nbd.2015.02.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 12/29/2014] [Accepted: 02/13/2015] [Indexed: 01/02/2023] Open
Abstract
There is a well-described association between infantile epilepsy and pervasive cognitive and behavioral deficits, including a high incidence of autism spectrum disorders. Despite the robustness of the relationship between early-life seizures and the development of autism, the pathophysiological mechanism by which this occurs has not been explored. As a result of increasing evidence that autism is a disorder of brain connectivity we hypothesized that early-life seizures would interrupt normal brain connectivity during brain maturation and result in an autistic phenotype. Normal rat pups underwent recurrent flurothyl-induced seizures from postnatal (P)days 5-14 and then tested, along with controls, for developmental alterations of development brain oscillatory activity from P18-P25. Specifically we wished to understand how normal changes in rhythmicity in and between brain regions change as a function of age and if this rhythmicity is altered or interrupted by early life seizures. In rat pups with early-life seizures, field recordings from dorsal and ventral hippocampus and prefrontal cortex demonstrated marked increase in coherence as well as a decrease in voltage correlation at all bandwidths compared to controls while there were minimal differences in total power and relative power spectral densities. Rats with early-life seizures had resulting impairment in the sociability and social novelty tests but demonstrated no evidence of increased activity or generalized anxiety as measured in the open field. In addition, rats with early-life seizures had lower seizure thresholds than controls, indicating long-standing alterations in the excitatory/inhibition balance. Bumetanide, a pharmacological agent that blocks the activity of NKCC1 and induces a significant shift of ECl toward more hyperpolarized values, administration at the time of the seizures precluded the subsequent abnormalities in coherence and voltage correlation and resulted in normal sociability and seizure threshold. Taken together these findings indicate that early-life seizures alter the development of oscillations and result in autistic-like behaviors. The altered communication between these brain regions could reflect the physiological underpinnings underlying social cognitive deficits seen in autism spectrum disorders.
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Affiliation(s)
- Gregory L Holmes
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA.
| | - Chengju Tian
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA
| | - Amanda E Hernan
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA
| | - Sean Flynn
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA
| | - Devon Camp
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA
| | - Jeremy Barry
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT05405, USA
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19
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Bernard PB, Benke TA. Early life seizures: evidence for chronic deficits linked to autism and intellectual disability across species and models. Exp Neurol 2014; 263:72-8. [PMID: 25284323 DOI: 10.1016/j.expneurol.2014.09.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/02/2014] [Accepted: 09/16/2014] [Indexed: 11/08/2022]
Abstract
Recent work in Exp Neurol by Lugo et al. (2014b) demonstrated chronic alterations in sociability, learning and memory following multiple early life seizures (ELS) in a mouse model. This work adds to the growing body of evidence supporting the detrimental nature of ELS on the developing brain to contribute to aspects of an autistic phenotype with intellectual disability. Review of the face validity of behavioral testing and the construct validity of the models used informs the predictive ability and thus the utility of these models to translate underlying molecular and cellular mechanisms into future human studies.
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Affiliation(s)
- Paul B Bernard
- Department of Pediatrics, University of Colorado, School of Medicine, USA
| | - Tim A Benke
- Department of Pediatrics, University of Colorado, School of Medicine, USA; Neuroscience Graduate Program, University of Colorado, School of Medicine, USA; Department of Neurology, University of Colorado, School of Medicine, USA; Department of Pharmacology, University of Colorado, School of Medicine, USA; Department of Otolaryngology, University of Colorado, School of Medicine, USA.
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20
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Glass HC, Wusthoff CJ, Shellhaas RA, Tsuchida TN, Bonifacio SL, Cordeiro M, Sullivan J, Abend NS, Chang T. Risk factors for EEG seizures in neonates treated with hypothermia: a multicenter cohort study. Neurology 2014; 82:1239-44. [PMID: 24610326 DOI: 10.1212/wnl.0000000000000282] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To assess the risk factors for electrographic seizures among neonates treated with therapeutic hypothermia for hypoxic-ischemic encephalopathy (HIE). METHODS Three-center observational cohort study of 90 term neonates treated with hypothermia, monitored with continuous video-EEG (cEEG) within the first day of life (median age at onset of recording 9.5 hours, interquartile range 6.3-14.5), and continued for >24 hours (total recording 93.3 hours, interquartile range 80.1-112.8 among survivors). A pediatric electroencephalographer at each site reviewed cEEGs for electrographic seizures and initial EEG background category. RESULTS A total of 43 (48%) had electrographic seizures, including 9 (10%) with electrographic status epilepticus. Abnormal initial EEG background classification (excessively discontinuous, depressed and undifferentiated, burst suppression, or extremely low voltage), but not clinical variables (including pH <6.8, base excess ≤-20, or 10-minute Apgar ≤ 3), was strongly associated with seizures. CONCLUSIONS Electrographic seizures are common among neonates with HIE undergoing hypothermia and are difficult to predict based on clinical features. These results justify the recommendation for cEEG monitoring in neonates treated with hypothermia.
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Affiliation(s)
- Hannah C Glass
- From the Departments of Neurology (H.C.G., J.S.) and Pediatrics (H.C.G., S.L.B., J.S.), University of California, San Francisco; Division of Child Neurology (C.J.W.), Stanford University School of Medicine, California; the Departments of Neurology and Pediatrics (N.S.A.), The Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania; the Department of Pediatrics & Communicable Diseases (Division of Pediatric Neurology) (R.A.S.), University of Michigan, Ann Arbor; and the Division of Neurophysiology, Epilepsy & Critical Care (T.N.T., M.C., T.C.), Children's National Medical Center, Washington, DC
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