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Yayıcı Köken Ö, Şekeroğlu B, Şanlıdağ B, Sarı Yanartaş M, Yılmaz A. Focality in childhood absence epilepsy. Neurol Res 2024; 46:626-633. [PMID: 38643974 DOI: 10.1080/01616412.2024.2339114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 03/31/2024] [Indexed: 04/23/2024]
Abstract
BACKGROUND AND PURPOSE Childhood absence epilepsy (CAE) has a typical electroencephalography (EEG) pattern of generalized 3 Hz spike and wave discharges (SWD). Focal interictal discharges were also documented in a small number of documents. The aim was to investigate the amplitudes of interictal 3 Hz SWD within the 1st second in drug-naïve CAE patients. In this way, areas with maximal electronegativity at the beginning of clinically generalized discharges will be documented. METHODS The EEG records of children with drug-naïve CAE were evaluated retrospectively by two child neurologists first for 3 Hz SWD. Then, a machine-learning model evaluated the amplitudes of 3 Hz in the 1st second of SWD. Maximum electronegativity areas were documented and classified as focal, bilateral, and generalized. RESULTS One hundred and twelve 3 Hz SWD were evaluated in 11 patients. Among discharges within the 1st second, maximum electronegativity areas were documented as focal for 44 (39.2%), bilateral for 8 (7.1%), generalized for 60 (53.5%). Among focal electronegativity areas, mostly right central, left occipital and midline parietal areas were documented in 12 (10.7%), 7 (6.2%), and 6 (5.3%), respectively. Eight (7.1%) of the maximum electronegativity areas were detected bilaterally, of which 7 (6.2%) originated from the frontopolar areas. CONCLUSIONS Focal maximal electronegativity areas were frequently observed in drug-naïve CAE patients, comprising approximately half of non-generalized discharges. Focal discharges might be misleading in diagnosis. Focal areas within the brain may be responsible for and contribute to absence seizures that appear bilaterally symmetrical and generalized clinically. Although its clinical implication is unknown, this warrants further study.
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Affiliation(s)
- Özlem Yayıcı Köken
- Faculty of Medicine, Department of Pediatric Neurology, Akdeniz University, Antalya, Turkey
| | - Boran Şekeroğlu
- Artificial Intelligence Engineering, Near East University, Nicosia, Cyprus
- DESAM Institute, Near East University, Nicosia, Cyprus
| | - Burçin Şanlıdağ
- Faculty of Medicine, Department of Pediatric Neurology, Near East University, Nicosia, Cyprus
| | - Mehpare Sarı Yanartaş
- Faculty of Medicine, Department of Pediatric Neurology, Akdeniz University, Antalya, Turkey
| | - Arzu Yılmaz
- Ministry of Health, Ankara Research and Training Hospital, Department of Pediatric Neurology, Ankara, Turkey
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2
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Filippi C, Damioli S, Accorsi P, Crotti E, Fazzi EM, Galli J, Martelli P, Morandi A, Muda A, Pinghini S, Saottini S, Sforza SE, Milito G, Giordano L. Early onset absence epilepsy of childhood: Epidemiologic data, treatment and outcome in a sample of 56 patients born between 2000 and 2018. Seizure 2024; 118:47-52. [PMID: 38636356 DOI: 10.1016/j.seizure.2024.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/20/2024] Open
Abstract
PURPOSE The aim of our work is to describe the characteristics of Early Onset Absence Epilepsy (EOAE) and to observe whether specific anamnestic, clinical or electroencephalographic characteristics can influence the drug sensitivity of this pathology. METHODS We carried out a retrospective study of patients affected by absence epilepsy with onset under four years of age, born between January 1st 2000 and December 31st 2018, who were reffered to the Regional Epilepsy Center of Spedali Civili of Brescia. We then divided the sample into three groups based on the age of onset. RESULTS Our sample is composed of 56 patients. Among the children with epilepsy onset under two years of age (11), all were still on therapy after three and six years of follow-up, and 64 % of them required polytherapy. Among patients with epilepsy onset between two and three years of age (24), 87 % were still on therapy after three years of follow-up and 68 % after six years of follow-up; 46 % of these subjects required polytherapy. Among patients with epilepsy onset between three and four years of age (21), 89 % were still on therapy after three years of follow-up and 38 % after six years of follow-up; 38 % of them required polytherapy. CONCLUSIONS We observe that patients with an earlier epilepsy onset have a worse outcome and a lower drug sensitivity. This may allow to predict in which cases it would be appropriate to maintain antiseizure therapy for a prolonged period.
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Affiliation(s)
- C Filippi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy.
| | - S Damioli
- NeMO - Brescia Clinical Center for Neuromuscular Diseases, Brescia Italy
| | - P Accorsi
- Epilepsy Regional Center, Unit of Child Neurology and Psychiatry - ASST Spedali Civili of Brescia, Brescia Italy
| | - E Crotti
- Epilepsy Regional Center, Unit of Child Neurology and Psychiatry - ASST Spedali Civili of Brescia, Brescia Italy
| | - E M Fazzi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy; Unit of Child Neurology and Psychiatry, ASST Spedali Civili of Brescia, Brescia Italy
| | - J Galli
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - P Martelli
- Epilepsy Regional Center, Unit of Child Neurology and Psychiatry - ASST Spedali Civili of Brescia, Brescia Italy
| | - A Morandi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - A Muda
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - S Pinghini
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - S Saottini
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - S E Sforza
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia Italy
| | - G Milito
- Epilepsy Regional Center, Unit of Child Neurology and Psychiatry - ASST Spedali Civili of Brescia, Brescia Italy
| | - L Giordano
- Epilepsy Regional Center, Unit of Child Neurology and Psychiatry - ASST Spedali Civili of Brescia, Brescia Italy
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Kim JH, Chen W, Chao ES, Rivera A, Kaku HN, Jiang K, Lee D, Chen H, Vega JM, Chin TV, Jin K, Nguyen KT, Zou SS, Moin Z, Nguyen S, Xue 薛名杉 M. GABAergic/Glycinergic and Glutamatergic Neurons Mediate Distinct Neurodevelopmental Phenotypes of STXBP1 Encephalopathy. J Neurosci 2024; 44:e1806232024. [PMID: 38360746 PMCID: PMC10993039 DOI: 10.1523/jneurosci.1806-23.2024] [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] [Received: 09/22/2023] [Revised: 01/09/2024] [Accepted: 01/26/2024] [Indexed: 02/17/2024] Open
Abstract
An increasing number of pathogenic variants in presynaptic proteins involved in the synaptic vesicle cycle are being discovered in neurodevelopmental disorders. The clinical features of these synaptic vesicle cycle disorders are diverse, but the most prevalent phenotypes include intellectual disability, epilepsy, movement disorders, cerebral visual impairment, and psychiatric symptoms ( Verhage and Sørensen, 2020; Bonnycastle et al., 2021; John et al., 2021; Melland et al., 2021). Among this growing list of synaptic vesicle cycle disorders, the most frequent is STXBP1 encephalopathy caused by de novo heterozygous pathogenic variants in syntaxin-binding protein 1 (STXBP1, also known as MUNC18-1; Verhage and Sørensen, 2020; John et al., 2021). STXBP1 is an essential protein for presynaptic neurotransmitter release. Its haploinsufficiency is the main disease mechanism and impairs both excitatory and inhibitory neurotransmitter release. However, the disease pathogenesis and cellular origins of the broad spectrum of neurological phenotypes are poorly understood. Here we generate cell type-specific Stxbp1 haploinsufficient male and female mice and show that Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons causes developmental delay, epilepsy, and motor, cognitive, and psychiatric deficits, recapitulating majority of the phenotypes observed in the constitutive Stxbp1 haploinsufficient mice and STXBP1 encephalopathy. In contrast, Stxbp1 haploinsufficiency in glutamatergic neurons results in a small subset of cognitive and seizure phenotypes distinct from those caused by Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons. Thus, the contrasting roles of excitatory and inhibitory signaling reveal GABAergic/glycinergic dysfunction as a key disease mechanism of STXBP1 encephalopathy and suggest the possibility to selectively modulate disease phenotypes by targeting specific neurotransmitter systems.
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Affiliation(s)
- Joo Hyun Kim
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Wu Chen
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Eugene S Chao
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Armando Rivera
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Heet Naresh Kaku
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Kevin Jiang
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Dongwon Lee
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Hongmei Chen
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Jaimie M Vega
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Teresa V Chin
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Kevin Jin
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Kelly T Nguyen
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Sheldon S Zou
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Zain Moin
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Shawn Nguyen
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
| | - Mingshan Xue 薛名杉
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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Zhao X, He Z, Li Y, Yang X, Li B. Atypical absence seizures and gene variants: A gene-based review of etiology, electro-clinical features, and associated epilepsy syndrome. Epilepsy Behav 2024; 151:109636. [PMID: 38232560 DOI: 10.1016/j.yebeh.2024.109636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/01/2024] [Accepted: 01/05/2024] [Indexed: 01/19/2024]
Abstract
Atypical absence seizures are generalized non-convulsive seizures that often occur in children with cognitive impairment. They are common in refractory epilepsy and have been recognized as one of the hallmarks of developmental epileptic encephalopathies. Notably, pathogenic variants associated with AAS, such as GABRG2, GABRG3, SLC6A1, CACNB4, SCN8A, and SYNGAP1, are also linked to developmental epileptic encephalopathies. Atypical absences differ from typical absences in that they are frequently drug-resistant and the prognosis is dependent on the etiology or related epileptic syndromes. To improve clinicians' understanding of atypical absences and provide novel perspectives for clinical treatment, we have reviewed the electro-clinical characteristics, etiologies, treatment, and prognosis of atypical absences, with a focus on the etiology of advancements in gene variants, shedding light on potential avenues for improved clinical management.
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Affiliation(s)
| | - Zimeng He
- Shandong University, Jinan, Shandong, China
| | - Yumei Li
- Shandong University, Jinan, Shandong, China
| | - Xiaofan Yang
- Shandong University, Jinan, Shandong, China; Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.
| | - Baomin Li
- Shandong University, Jinan, Shandong, China; Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.
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Li SP, Lin LC, Yang RC, Ouyang CS, Chiu YH, Wu MH, Tu YF, Chang TM, Wu RC. Predicting the therapeutic response to valproic acid in childhood absence epilepsy through electroencephalogram analysis using machine learning. Epilepsy Behav 2024; 151:109647. [PMID: 38232558 DOI: 10.1016/j.yebeh.2024.109647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/30/2023] [Accepted: 01/10/2024] [Indexed: 01/19/2024]
Abstract
Childhood absence epilepsy (CAE) is a common type of idiopathic generalized epilepsy, manifesting as daily multiple absence seizures. Although seizures in most patients can be adequately controlled with first-line antiseizure medication (ASM), approximately 25 % of patients respond poorly to first-line ASM. In addition, an accurate method for predicting first-line medication responsiveness is lacking. We used the quantitative electroencephalogram (QEEG) features of patients with CAE along with machine learning to predict the therapeutic effects of valproic acid in this population. We enrolled 25 patients with CAE from multiple medical centers. Twelve patients who required additional medication for seizure control or who were shifted to another ASM and 13 patients who achieved seizure freedom with valproic acid within 6 months served as the nonresponder and responder groups. Using machine learning, we analyzed the interictal background EEG data without epileptiform discharge before ASM. The following features were analyzed: EEG frequency bands, Hjorth parameters, detrended fluctuation analysis, Higuchi fractal dimension, Lempel-Ziv complexity (LZC), Petrosian fractal dimension, and sample entropy (SE). We applied leave-one-out cross-validation with support vector machine, K-nearest neighbor (KNN), random forest, decision tree, Ada boost, and extreme gradient boosting, and we tested the performance of these models. The responders had significantly higher alpha band power and lower delta band power than the nonresponders. The Hjorth mobility, LZC, and SE values in the temporal, parietal, and occipital lobes were higher in the responders than in the nonresponders. Hjorth complexity was higher in the nonresponders than in the responders in almost all the brain regions, except for the leads FP1 and FP2. Using KNN classification with theta band power in the temporal lobe yielded optimal performance, with sensitivity of 92.31 %, specificity of 76.92 %, accuracy of 84.62 %, and area under the curve of 88.46 %.We used various EEG features along with machine learning to accurately predict whether patients with CAE would respond to valproic acid. Our method could provide valuable assistance for pediatric neurologists in selecting suitable ASM.
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Affiliation(s)
- Sheng-Ping Li
- Division of Pediatric Neurology, Kaohsiung Medical University Chung-Ho Memorial Hospital, Taiwan
| | - Lung-Chang Lin
- Division of Pediatric Neurology, Kaohsiung Medical University Chung-Ho Memorial Hospital, Taiwan.
| | - Rei-Cheng Yang
- Division of Pediatric Neurology, Kaohsiung Medical University Chung-Ho Memorial Hospital, Taiwan
| | - Chen-Sen Ouyang
- Department of Information Management, National Kaohsiung University of Science and Technology, Taiwan
| | - Yi-Hung Chiu
- Department of Information Engineering, I-Shou University, Taiwan
| | - Mu-Han Wu
- Department of Neurology, Tainan Hospital, Ministry of Health and Welfare, Taiwan
| | - Yi-Fang Tu
- National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tung-Ming Chang
- Department of Pediatric Neurology, Changhua Christian Children's Hospital, Changhua, Taiwan
| | - Rong-Ching Wu
- Department of Electrical Engineering, I-Shou University, Taiwan
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6
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Eapen M, Iype M, Saradakutty G, Jayan BB, Sreedharan M, Ahamed S, Preethi Thomas E, Habeeb A, Cherian A. Childhood Absence Epilepsy- Electroclinical Profile and Prevalence of Attention-Deficit/Hyperactivity Disorder Among a Cohort of 47 Children. Pediatr Neurol 2024; 150:65-73. [PMID: 37981446 DOI: 10.1016/j.pediatrneurol.2023.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 09/29/2023] [Accepted: 10/24/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND We aimed to find the proportion of attention-deficit/hyperactivity disorder (ADHD) among children with childhood absence epilepsy (CAE) and to describe their electroclinical features. METHODS Video electroencephalography (EEG) was performed on 47 children who fulfilled International League Against Epilepsy criteria for CAE. These children were also assessed for the presence of ADHD. RESULTS Of the 47 children, 27 (57%) met criteria for the diagnosis of ADHD. Majority (74%) of them had inattentive type of ADHD. Age at onset of absences ranged from three to 12 years (mean 7.2 ± 2.47). We analyzed 219 seizures (154 electroclinical and 65 electrographic). The average seizure duration was 7.1 seconds (range 1 to 38 [S.D. 5.81]). Of the 154 clinical absences, ictal discharges were less than or equal to two seconds in nine of 154 (5.8%); greater than two to less than or equal to four seconds in 33 of 154 (21.4%), and longer than 20 seconds in 11 of 154 (7%). The longest duration of ictal discharge recorded was 38 seconds, and the shortest duration was one second. The onset of ictal discharge had a "lead in" focus in 81% (177 of 219). CONCLUSIONS The proportion of ADHD among children with CAE is high. A "lead in" focus of the generalized ictal discharges was observed frequently, lending support to the theory that the origin of seizure discharges in CAE is indeed cortical. The shortest ictal discharge recorded was one second.
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Affiliation(s)
- Merin Eapen
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India.
| | - Mary Iype
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
| | - Geetha Saradakutty
- Department of Paediatrics, Government Medical College, Konni, Kerala, India
| | - Bineej B Jayan
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
| | - Mini Sreedharan
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
| | - Shahanaz Ahamed
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
| | | | - Azmi Habeeb
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
| | - Anchu Cherian
- Department of Paediatric Neurology, Government Medical College, Trivandrum, Kerala, India
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Harvey S, Thompson C, O'Flaherty O, Scott L, O'Malley S, O'Rourke D, Lynch B, Gorman KM, Conroy E, Shahwan A. Relationship Between Electroencephalography and Seizure Outcome in Typical Absence Seizures in Children. Pediatr Neurol 2023; 148:56-64. [PMID: 37666206 DOI: 10.1016/j.pediatrneurol.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/18/2023] [Accepted: 08/03/2023] [Indexed: 09/06/2023]
Abstract
BACKGROUND Typical absence seizures (TAS) are seen in idiopathic generalized epilepsy. Electroencephalography (EEG) contributes to syndrome characterization and counseling in an area where genetics does not currently play a significant role. Prominent interictal EEG findings are seen in juvenile absence epilepsy (JAE) and are thus thought to be associated with less favorable outcome in any TAS case despite lack of evidence. Our study evaluates EEG findings and their association with seizure outcomes in children with TAS. METHODS Retrospective cohort study of 123 children over 10 years with extensive EEG analysis and medical record review. Phone interviews ascertained longer-term outcomes. EEG reviewers were unaware of outcomes. RESULTS Total cohort included 123 children with phone review completed in 98. Median follow-up was 5 years 9 months. Seizure freedom was seen in 59% off antiseizure medicines (ASMs). Interictal findings included focal discharges in 29%, fragments of spike-wave (SW) discharges in 82.1%, and generalized interictal discharges in 63.4%. Interictal SW was more likely in those who slept (100%, 18 of 18) versus those who did not (57%, 60 of 105) (P < 0.001). Outcome analysis found no associations between focal or generalized interictal findings and seizure freedom, relapse off ASM, occurrence of other seizure types, or response to first ASM. CONCLUSION Focal and generalized interictal EEG discharges are common in children with TAS and are not associated with poorer outcomes. These interictal findings were traditionally associated with JAE rather than childhood absence epilepsy and were thus believed to be associated with potentially poorer outcome, which is probably not the case.
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Affiliation(s)
- Susan Harvey
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland.
| | - Claire Thompson
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Odette O'Flaherty
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Louise Scott
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Siobhan O'Malley
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Declan O'Rourke
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Bryan Lynch
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Kathleen M Gorman
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Emily Conroy
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Amre Shahwan
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland; School of Medicine, Royal College of Surgeons Ireland, Dublin, Ireland
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Zhao J, Yu Y, Han F, Wang Q. Regulating epileptiform discharges by heterogeneous interneurons in thalamocortical model. CHAOS (WOODBURY, N.Y.) 2023; 33:083128. [PMID: 37561121 DOI: 10.1063/5.0163243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 07/25/2023] [Indexed: 08/11/2023]
Abstract
Inhibitory interneurons in the cortex are abundant and have diverse roles, classified as parvalbumin (PV), somatostatin (SOM), and vasoactive intestinal polypeptide (VIP) according to chemically defined categories. Currently, their involvement with seizures has been partially uncovered in physiological terms. Here, we propose a corticothalamic model containing heterogeneous interneurons to study the effects of various interneurons on absence seizure dynamics by means of optogenetic stimulation. First, the important role of feedforward inhibition caused by SRN→PV→PN projections on seizures is verified. Then, we demonstrate that light activation targeting either PV or SOM INs can control seizures. Finally, with different inhibition contributions from PV INs and SOM INs, the possible disinhibitory effect of blue light acting on VIP INs is mainly discussed. The results suggest that depending on the inhibition degree of both types, the disinhibition brought about by the VIP INs will trigger seizures, will control seizures, and will not work or cause the PNs to tend toward a high saturation state with high excitability. The circuit mechanism and the related bifurcation characteristics in various cases are emphatically revealed. In the model presented, in addition to Hopf and saddle-node bifurcations, the system may also undergo period-doubling and torus bifurcations under stimulus action, with more complex dynamics. Our work may provide a theoretical basis for understanding and further exploring the role of heterogeneous interneurons, in particular, the VIP INs, a novel target, in absence seizures.
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Affiliation(s)
- Jinyi Zhao
- Department of Dynamics and Control, Beihang University, Beijing 100191, China
| | - Ying Yu
- School of Engineering Medicine, Beihang University, Beijing 100191, China
| | - Fang Han
- College of Information Science and Technology, Donghua University, Shanghai 201620, China
| | - Qingyun Wang
- Department of Dynamics and Control, Beihang University, Beijing 100191, China
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9
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Harvey S, Shahwan A. Typical absence seizures in children: Review with focus on EEG predictors of treatment response and outcome. Seizure 2023; 110:1-10. [PMID: 37295276 DOI: 10.1016/j.seizure.2023.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/13/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
Typical absence seizures (TAS) occur in idiopathic generalized epilepsy (IGE) syndromes and are a common presentation to paediatric neurologists. Considerable overlap in clinical features of IGE syndromes comprising TAS often complicates prognostication. Clinical and EEG diagnostic features in TAS are well known. However, knowledge of prognostic features for each syndrome, whether clinical or EEG-related, is less clear. Perpetuated impressions in clinical practice regarding the role of EEG when used for prognostication in TAS are known. Assumed prognostic features, particularly those relating to EEG have been rarely studied systematically. Despite rapid expansion in epilepsy genetics, the complex and presumed polygenic inheritance of IGE, means that clinical and EEG features are likely to remain the main guide to management and prognostication of TAS for the foreseeable future. We comprehensively reviewed available literature and hereby summarize current knowledge of clinical and EEG characteristics (ictal and interictal) in children with TAS. The literature focuses predominantly on ictal EEG. Where studied, interictal findings reported relate to focal discharges, polyspike discharges, and occipital intermittent rhythmic delta activity, with generalized interictal discharges not thoroughly studied. Furthermore, reported prognostic implications of EEG findings are often conflicting. Limitations of available literature include inconsistent clinical syndrome and EEG finding definitions, and variable EEG analysis methods, particularly lack of raw EEG data analysis. These conflicting findings coupled with varying study methodologies cause lack of clear information or evidence on features which may influence treatment response, outcome, or natural history of TAS.
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Affiliation(s)
- Susan Harvey
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Temple Street, Dublin 1, Ireland; School of Medicine, University College Dublin, Dublin Ireland.
| | - Amre Shahwan
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Temple Street, Dublin 1, Ireland; School of Medicine, Royal College of Surgeons Ireland, Dublin, Ireland
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10
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Sitnikova E, Pupikina M, Rutskova E. Alpha2 Adrenergic Modulation of Spike-Wave Epilepsy: Experimental Study of Pro-Epileptic and Sedative Effects of Dexmedetomidine. Int J Mol Sci 2023; 24:ijms24119445. [PMID: 37298397 DOI: 10.3390/ijms24119445] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/20/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
In the present report, we evaluated adrenergic mechanisms of generalized spike-wave epileptic discharges (SWDs), which are the encephalographic hallmarks of idiopathic generalized epilepsies. SWDs link to a hyper-synchronization in the thalamocortical neuronal activity. We unclosed some alpha2-adrenergic mechanisms of sedation and provocation of SWDs in rats with spontaneous spike-wave epilepsy (WAG/Rij and Wistar) and in control non-epileptic rats (NEW) of both sexes. Dexmedetomidine (Dex) was a highly selective alpha-2 agonist (0.003-0.049 mg/kg, i.p.). Injections of Dex did not elicit de novo SWDs in non-epileptic rats. Dex can be used to disclose the latent form of spike-wave epilepsy. Subjects with long-lasting SWDs at baseline were at high risk of absence status after activation of alpha2- adrenergic receptors. We create the concept of alpha1- and alpha2-ARs regulation of SWDs via modulation of thalamocortical network activity. Dex induced the specific abnormal state favorable for SWDs-"alpha2 wakefulness". Dex is regularly used in clinical practice. EEG examination in patients using low doses of Dex might help to diagnose the latent forms of absence epilepsy (or pathology of cortico-thalamo-cortical circuitry).
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Affiliation(s)
- Evgenia Sitnikova
- Institute of the Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str., 5A, 117485 Moscow, Russia
| | - Maria Pupikina
- Institute of the Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str., 5A, 117485 Moscow, Russia
| | - Elizaveta Rutskova
- Institute of the Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova Str., 5A, 117485 Moscow, Russia
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11
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Gregorčič S, Hrovat J, Bizjak N, Rener Primec Z, Hostnik T, Stres B, Perković Benedik M, Osredkar D. Difficult to treat absence seizures in children: A single-center retrospective study. Front Neurol 2022; 13:958369. [PMID: 36247779 PMCID: PMC9556893 DOI: 10.3389/fneur.2022.958369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/06/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectivesThe aim of this study was to analyse the characteristics of typical absence seizures (AS), myoclonic AS and AS with eyelid myoclonia in children and to find associations between these characteristics and difficult to treat absence seizures (DTAS).MethodsThis was a single-center retrospective study. Electronic health records of pediatric patients with a clinical diagnosis of AS treated at a single tertiary epilepsy center between January 2013 and June 2020 were reviewed. Clinical characteristics, seizure information, ASM, and therapeutic response of patients were recorded. All patients were followed up for at least 1 year. DTAS were defined as failure to achieve remission after treatment with at least 2 anti-seizure medications (ASM), regardless of whether remission was achieved eventually in the study period.ResultsData from 131 patients were available for analysis. Remission was achieved after the first ASM treatment in 81 (61.8%) patients, and eventually in 120 (91.6%) during the study period. Epilepsy was classified as DTAS in 18 (13.7%) patients. AS were more often difficult to treat in patients with myoclonic AS and AS with eyelid myoclonia (40.0%), compared with patients with typical AS (11.4%; p = 0.012, 95% CI 1.480–25.732). A positive family history of epilepsy (p = 0.046; 95% CI 1.021–8.572), a higher seizure frequency (p = 0.023, 95% CI 1.009–1.126) prior to ASM treatment, and longer time between seizure onset and treatment onset (p = 0.026; 95% CI 1.006–1.099) were also associated with DTAS.SignificanceOur study suggests that several clinical characteristics of AS are associated with DTAS. One of these was the time between onset of AS and initiation of ASM treatment, which can be shortened with better care, suggesting that early diagnosis and treatment may improve prognosis in pediatric patients with AS. These findings remain to be confirmed in larger prospective studies.
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Affiliation(s)
- Samo Gregorčič
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Jaka Hrovat
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Neli Bizjak
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, Centre for Developmental Neuroscience, University of Ljubljana, Ljubljana, Slovenia
| | - Zvonka Rener Primec
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, Centre for Developmental Neuroscience, University of Ljubljana, Ljubljana, Slovenia
| | - Tadeja Hostnik
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Blaž Stres
- Department of Animal Science, Faculty of Biotechnical, University of Ljubljana, Ljubljana, Slovenia
- Department of Automation, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia
- Faculty of Civil and Geodetic Engineering, Institute of Sanitary Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Mirjana Perković Benedik
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, Centre for Developmental Neuroscience, University of Ljubljana, Ljubljana, Slovenia
- *Correspondence: Mirjana Perković Benedik
| | - Damjan Osredkar
- Department of Pediatric Neurology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, Centre for Developmental Neuroscience, University of Ljubljana, Ljubljana, Slovenia
- Damjan Osredkar
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12
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Özçelik EU, Çokar Ö, Demirbilek V. Pretreatment electroencephalographic features in patients with childhood absence epilepsy. Neurophysiol Clin 2022; 52:280-289. [PMID: 35953417 DOI: 10.1016/j.neucli.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 10/15/2022] Open
Abstract
OBJECTIVE To analyze the ictal and interictal electroencephalographic (EEG) features in newly diagnosed childhood absence epilepsy (CAE) and determine the association between seizure onset topography, interictal focal spike-wave discharges (FSWDs) and accompanying clinical features of absence seizures. METHODS The authors searched the EEG database for a definite diagnosis of CAE according to ILAE 2017 criteria. Video-EEGs of untreated pediatric patients during sleep and wakefulness were evaluated retrospectively. RESULTS The study included 47 patients (25 males, 22 females). Interictal FSWDs were observed in 49% of patients with CAE during wakefulness and in 85.1% during sleep (p = 0.001). Interictal FSWDs were most frequently observed in the frontal regions (awake: 34%; asleep: 74.5%), followed by the posterior temporoparietooccipital region (awake: 21.2%; asleep: 36.1%), and the centrotemporal region (awake: 6.4%; asleep: 8.5%). Eleven patients (23.4%) had polyspikes during sleep. Both bilateral symmetric and asymmetric seizure onset were noted in 32%, whereas focal seizure onset was observed in 14.9% of the patients. Absence seizures with and without motor components were seen in 72.3% and 61.7% of patients, respectively, and in 33% of patients both occurred. There were no associations between the existence of interictal FSWDs, focal/asymmetric seizure onset, and absence seizures with and/or without motor components. CONCLUSION Asymmetric and/or focal seizure onset, interictal FSWDs, and absence seizures with motor components are commonly observed in drug-naive CAE. This study found no association between seizure onset topography, interictal FSWDs, and semiological features of absence seizures.
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Affiliation(s)
- Emel Ur Özçelik
- Istanbul University, Cerrahpaşa School of Medicine, Departments of Neurology and Childhood Neurology, Istanbul, Türkiye; Istanbul Health and Technology University, Faculty of Health Sciences, Department of Ergotherapy, Istanbul, Türkiye.
| | - Özlem Çokar
- University of Health Sciences, Hamidiye School of Medicine, Haseki Educational and Research Hospital, Department of Neurology, Istanbul, Türkiye
| | - Veysi Demirbilek
- Istanbul University, Cerrahpaşa School of Medicine, Departments of Neurology and Childhood Neurology, Istanbul, Türkiye
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13
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Zhang H, Chen Y, Xie Y, Chai Y. Closed-loop controller based on reference signal tracking for absence seizures. Sci Rep 2022; 12:6730. [PMID: 35468988 PMCID: PMC9038751 DOI: 10.1038/s41598-022-10803-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 04/12/2022] [Indexed: 11/30/2022] Open
Abstract
Absent epilepsy is a kind of refractory epilepsy, which is characterized by 2–4 Hz spike and wave discharges (SWDs) in electroencephalogram. Open-loop deep brain stimulation (DBS) targeting the thalamic reticular nucleus (TRN) is an effective method to treat absent epilepsy by eliminating SWDs in the brain. Compared with open-loop DBS, closed-loop DBS has been recognized by researchers for its advantages of significantly inhibiting seizures and having fewer side effects. Since traditional trial-and-error methods for adjusting closed-loop controller parameters are too dependent on the experience of doctors, in this paper we designed two proportional integral (PI) controllers based on the basal ganglia-cortical-thalamic model, whose PI parameters are calculated from the stability of the system. The two PI controllers can automatically adjust the frequency and amplitude of DBS respectively according to the change of the firing rate detected by substantia nigra pars reticulata (SNr). The parameters of the PI controller are calculated based on the Routh-Hurwitz stability criterion of a linear system which transformed by the original system using controlled auto-regressive (CAR) model and recursive least squares (RLS) method. Numerical simulation results show that both PI controllers significantly destroy the SWDs of the cerebral cortex and restore it to the other two normal discharge modes according to the different target firing rate, which supplies a promising brain stimulation strategy.
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Affiliation(s)
- Hudong Zhang
- School of Mathematics and Physics, Shanghai University of Electric Power, Shanghai, 201306, China
| | - Yuting Chen
- School of Mathematics and Physics, Shanghai University of Electric Power, Shanghai, 201306, China
| | - Yan Xie
- School of Mathematics and Physics, Shanghai University of Electric Power, Shanghai, 201306, China
| | - Yuan Chai
- School of Mathematics and Physics, Shanghai University of Electric Power, Shanghai, 201306, China.
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14
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Yang Q, Hu D, Wang T, Cao J, Dong F, Gao W, Jiang T, Gao F. Childhood epilepsy syndromes classification based on fused features of electroencephalogram and electrocardiogram. COGNITIVE COMPUTATION AND SYSTEMS 2022. [DOI: 10.1049/ccs2.12035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Qianlan Yang
- Machine Learning and I‐health International Cooperation Base of Zhejiang Province Hangzhou Dianzi University Hangzhou China
| | - Dinghan Hu
- Machine Learning and I‐health International Cooperation Base of Zhejiang Province Hangzhou Dianzi University Hangzhou China
- Artificial Intelligence Institute Hangzhou Dianzi University Hangzhou China
| | - Tianlei Wang
- Machine Learning and I‐health International Cooperation Base of Zhejiang Province Hangzhou Dianzi University Hangzhou China
- Artificial Intelligence Institute Hangzhou Dianzi University Hangzhou China
| | - Jiuwen Cao
- Machine Learning and I‐health International Cooperation Base of Zhejiang Province Hangzhou Dianzi University Hangzhou China
- Artificial Intelligence Institute Hangzhou Dianzi University Hangzhou China
| | - Fang Dong
- School of Information and Electrical Engineering Zhejiang University City College Hangzhou China
| | - Weidong Gao
- School of Science and Engineering The Chinese University of Hong Kong Shenzhen China
| | - Tiejia Jiang
- Zhejiang University School of Medicine Children's Hospital Hangzhou China
| | - Feng Gao
- Zhejiang University School of Medicine Children's Hospital Hangzhou China
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15
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Baggio M, Toffoli L, Da Rold M, Duma GM, Mento G, Morao V, Danieli A, Bonanni P. Neuropsychological and behavioral profiles of self-limited epileptic syndromes of childhood: a cross-syndrome comparison. Child Neuropsychol 2022; 28:878-902. [PMID: 35086426 DOI: 10.1080/09297049.2022.2028754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Childhood epilepsy with centro-temporal spikes (CECTS), Childhood absence epilepsy (CAE) and Panayiotopoulos syndrome (PS) are some of the most common pediatric epileptic syndromes. Despite the relatively benign (self-limited) course of epilepsy, current evidence suggests that these conditions are associated with an increased risk of neuropsychological and behavioral comorbidities. This study provides a cross-epileptic syndromes' comparison reporting on the cognitive and behavioral profile of a cohort of 32 children with CECTS (n = 14), CAE (n = 10) and PS (n = 8), aged 6 to 15 years old. Frequent, although often subclinical cognitive difficulties involving attention, executive functions and academic abilities were found in children with CECTS and CAE, and to a lesser extent in PS. Internalizing symptoms (particularly anxiety) were more common in the PS group compared to CECTS and CAE based on parental reports. Correlational analysis revealed a significant correlation between phonemic fluency and seizure-free interval at the time of evaluation, suggesting a beneficial effect of epilepsy remission on this executive function measure in all the three groups. These results add to existing literature providing further detail on neuropsychological and behavioral peculiarities of children with CECTS, CAE, and PS. Moreover, the need for neuropsychological assessment as part of the standard childhood epilepsy evaluation is stressed. The results are discussed in the context of the current literature, highlighting areas of consensus and controversies related to the clinical management of these epileptic syndromes as well as directions for future research.
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Affiliation(s)
- Martina Baggio
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy
| | - Lisa Toffoli
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy.,Department of General Psychology, University of Padova, Italy
| | - Martina Da Rold
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy
| | - Gian Marco Duma
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy.,Department of General Psychology, University of Padova, Italy
| | - Giovanni Mento
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy.,Padova Neuroscience Center (PNC), University of Padova, Italy
| | - Veronica Morao
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy
| | - Alberto Danieli
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy
| | - Paolo Bonanni
- Epilepsy and Clinical Neurophysiology Unit, Irccs "E. Medea," Conegliano, Treviso, Italy
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16
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Gouveia FV, Germann J, Oliveira CC, Castro MC, Antunes GF, Gomes GCV, Pinto TRC, Martinez RCR, Valle AC. Transcranial Direct Current Stimulation Reduces Anxiety, Depression and Plasmatic Corticosterone in a Rat Model of Atypical Generalized Epilepsy. Neuroscience 2021; 480:32-41. [PMID: 34774711 DOI: 10.1016/j.neuroscience.2021.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/22/2021] [Accepted: 11/02/2021] [Indexed: 11/30/2022]
Abstract
Affective disorders (i.e. anxiety and depression) are commonly observed in patients with epilepsy and induce seizure aggravation. Animal models of epilepsy that exhibit affective disorder features are essential in developing new neuromodulatory treatments. GEAS-W rats (Generalized Epilepsy with Absence Seizures, Wistar background) are an inbred model of generalized epilepsy showing spontaneous spike-wave discharges concomitant with immobility. Transcranial Direct Current Stimulation (tDCS) is a safe non-invasive neuromodulatory therapy used to modulate dysfunctional circuitries frequently and successfully applied in affective disorders for symptom alleviation. Here we investigated anxiolytic and antidepressant effects of tDCS in GEAS-W rats and the role of corticosterone as a possible mechanism of action. GEAS-W and Wistar rats were randomly divided into control, sham-tDCS and active-tDCS groups. Both tDCS groups received 15 sessions of sham or active-tDCS (1 mA, cathode). Behavioural tests included the Open Field and Forced Swimming tests followed by corticosterone analysis. We observed a main effect of treatment and a significant treatment by strain interaction on anxiety-like and depressive-like behaviours, with active-tDCS GEAS-W rats entering the center of the open field more often and showing less immobility in the forced swimming test. Furthermore, there was a main effect of treatment on corticosterone with active-tDCS animals showing marked reduction in plasmatic levels. This study described preclinical evidence to support tDCS treatment of affective disorders in epilepsy and highlights corticosterone as a possible mechanism of action.
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Affiliation(s)
- Flavia Venetucci Gouveia
- Program in Neuroscience and Mental Health, Hospital for Sick Children Research Institute, Toronto, Canada; Division of Neuroscience, Sírio-Libanês Hospital, São Paulo, Brazil.
| | - Jürgen Germann
- Division of Neurosurgery, Department of Surgery, University Health Network and University of Toronto, Toronto, Canada
| | | | - Marina C Castro
- Division of Neuroscience, Sírio-Libanês Hospital, São Paulo, Brazil
| | - Geiza F Antunes
- Division of Neuroscience, Sírio-Libanês Hospital, São Paulo, Brazil
| | - Gisele C V Gomes
- Laboratory of Neuroscience LIM 01, Department of Pathology, University of Sao Paulo, School of Medicine, São Paulo, Brazil
| | - Tais R C Pinto
- Laboratory of Neuroscience LIM 01, Department of Pathology, University of Sao Paulo, School of Medicine, São Paulo, Brazil
| | - Raquel C R Martinez
- Division of Neuroscience, Sírio-Libanês Hospital, São Paulo, Brazil; LIM 23, Institute of Psychiatry, University of Sao Paulo, School of Medicine, São Paulo, Brazil.
| | - Angela C Valle
- Laboratory of Neuroscience LIM 01, Department of Pathology, University of Sao Paulo, School of Medicine, São Paulo, Brazil
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17
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Mastroianni G, Ascoli M, Gasparini S, Brigo F, Cianci V, Neri S, Russo E, Aguglia U, Ferlazzo E. Therapeutic approach to difficult-to-treat typical absences and related epilepsy syndromes. Expert Rev Clin Pharmacol 2021; 14:1427-1433. [PMID: 34289757 DOI: 10.1080/17512433.2021.1959317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Introduction: typical absences (TAs), are brief, generalized epileptic seizures of abrupt onset and termination clinically manifesting with impairment of awareness and associated with 3 Hz spike-wave discharges on EEG. TAs may occur in different idiopathic generalized epilepsies (IGE). Despite treatment with adequate anti-seizure medications (ASMs), TAs may persist in ~25% of subjects. This narrative review focuses on the therapeutic approach to difficult-to-treat TAs occurring in the setting of IGE.Areas covered: a literature search was conducted on the topic of treatment of TAs.Expert opinion: ethosuximide (ESX), valproic acid (VPA) and lamotrigine (LTG), alone or in combination, are considered the first-choice drugs. In women of childbearing potential, VPA should be avoided. Alternative therapies (benzodiazepines, levetiracetam, topiramate, or zonisamide) should be considered in subjects unresponsive to monotherapy after the exclusion of pseudo-drug resistance. Newer ASMs such as brivaracetam and perampanel seem to be promising options. Well-conducted clinical trials aimed to evaluate the efficacy of alternative monotherapy (beyond ESX, VPA or LTG) or combination of ASMs on difficult-to-treat TAs, are warranted.
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Affiliation(s)
- Giovanni Mastroianni
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy
| | - Michele Ascoli
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy.,Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Sara Gasparini
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy.,Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Francesco Brigo
- Department of Neurology, Hospital of Merano (SABES-ASDAA), Merano, Italy
| | - Vittoria Cianci
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy
| | - Sabrina Neri
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy.,Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Emilio Russo
- Science of Health Department, Magna Graecia University, Catanzaro, Italy
| | - Umberto Aguglia
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy.,Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| | - Edoardo Ferlazzo
- Regional Epilepsy Centre, Great Metropolitan "BMM" Hospital, Reggio, Calabria, Italy.,Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.,Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
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18
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Panthi S, Lyons NMA, Leitch B. Impact of Dysfunctional Feed-Forward Inhibition on Glutamate Decarboxylase Isoforms and γ-Aminobutyric Acid Transporters. Int J Mol Sci 2021; 22:ijms22147740. [PMID: 34299369 PMCID: PMC8306481 DOI: 10.3390/ijms22147740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 07/16/2021] [Indexed: 12/02/2022] Open
Abstract
Absence seizures are associated with generalised synchronous 2.5–4 Hz spike-wave discharges causing brief and sudden alteration of awareness during childhood, which is known as childhood absence epilepsy (CAE). CAE is also associated with impaired learning, psychosocial challenges, and physical danger. Absence seizures arise from disturbances within the cortico-thalamocortical (CTC) network, including dysfunctional feed-forward inhibition (FFI); however, the precise mechanisms remain unclear. In epileptic stargazers, a genetic mouse model of CAE with chronic seizures, levels of γ-aminobutyric acid (GABA), and expression of GABA receptors are altered within the CTC network, implicating altered GABAergic transmission in absence seizures. However, the expression of GABA synthesising enzymes (GAD65 and GAD67) and GABA transporters (GAT-1 and 3) have not yet been characterised within absence seizure models. We found a specific upregulation of GAD65 in the somatosensory cortex but not the thalamus of epileptic stargazer mice. No differences were detected in GAD67 and GAT-3 levels in the thalamus or somatosensory cortex. Then, we assessed if GAD65 upregulation also occurred in Gi-DREADD mice exhibiting acute absence seizures, but we found no change in the expression profiles of GAD65/67 or GAT-3. Thus, the upregulation of GAD65 in stargazers may be a compensatory mechanism in response to long-term dysfunctional FFI and chronic absence seizures.
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Affiliation(s)
| | | | - Beulah Leitch
- Correspondence: ; Tel.: +64-3-479-7618; Fax: +64-3-479-7254
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19
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Gobbo D, Scheller A, Kirchhoff F. From Physiology to Pathology of Cortico-Thalamo-Cortical Oscillations: Astroglia as a Target for Further Research. Front Neurol 2021; 12:661408. [PMID: 34177766 PMCID: PMC8219957 DOI: 10.3389/fneur.2021.661408] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 05/11/2021] [Indexed: 12/21/2022] Open
Abstract
The electrographic hallmark of childhood absence epilepsy (CAE) and other idiopathic forms of epilepsy are 2.5-4 Hz spike and wave discharges (SWDs) originating from abnormal electrical oscillations of the cortico-thalamo-cortical network. SWDs are generally associated with sudden and brief non-convulsive epileptic events mostly generating impairment of consciousness and correlating with attention and learning as well as cognitive deficits. To date, SWDs are known to arise from locally restricted imbalances of excitation and inhibition in the deep layers of the primary somatosensory cortex. SWDs propagate to the mostly GABAergic nucleus reticularis thalami (NRT) and the somatosensory thalamic nuclei that project back to the cortex, leading to the typical generalized spike and wave oscillations. Given their shared anatomical basis, SWDs have been originally considered the pathological transition of 11-16 Hz bursts of neural oscillatory activity (the so-called sleep spindles) occurring during Non-Rapid Eye Movement (NREM) sleep, but more recent research revealed fundamental functional differences between sleep spindles and SWDs, suggesting the latter could be more closely related to the slow (<1 Hz) oscillations alternating active (Up) and silent (Down) cortical activity and concomitantly occurring during NREM. Indeed, several lines of evidence support the fact that SWDs impair sleep architecture as well as sleep/wake cycles and sleep pressure, which, in turn, affect seizure circadian frequency and distribution. Given the accumulating evidence on the role of astroglia in the field of epilepsy in the modulation of excitation and inhibition in the brain as well as on the development of aberrant synchronous network activity, we aim at pointing at putative contributions of astrocytes to the physiology of slow-wave sleep and to the pathology of SWDs. Particularly, we will address the astroglial functions known to be involved in the control of network excitability and synchronicity and so far mainly addressed in the context of convulsive seizures, namely (i) interstitial fluid homeostasis, (ii) K+ clearance and neurotransmitter uptake from the extracellular space and the synaptic cleft, (iii) gap junction mechanical and functional coupling as well as hemichannel function, (iv) gliotransmission, (v) astroglial Ca2+ signaling and downstream effectors, (vi) reactive astrogliosis and cytokine release.
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Affiliation(s)
- Davide Gobbo
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
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20
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Christian CA, Reddy DS, Maguire J, Forcelli PA. Sex Differences in the Epilepsies and Associated Comorbidities: Implications for Use and Development of Pharmacotherapies. Pharmacol Rev 2021; 72:767-800. [PMID: 32817274 DOI: 10.1124/pr.119.017392] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The epilepsies are common neurologic disorders characterized by spontaneous recurrent seizures. Boys, girls, men, and women of all ages are affected by epilepsy and, in many cases, by associated comorbidities as well. The primary courses of treatment are pharmacological, dietary, and/or surgical, depending on several factors, including the areas of the brain affected and the severity of the epilepsy. There is a growing appreciation that sex differences in underlying brain function and in the neurobiology of epilepsy are important factors that should be accounted for in the design and development of new therapies. In this review, we discuss the current knowledge on sex differences in epilepsy and associated comorbidities, with emphasis on those aspects most informative for the development of new pharmacotherapies. Particular focus is placed on sex differences in the prevalence and presentation of various focal and generalized epilepsies; psychiatric, cognitive, and physiologic comorbidities; catamenial epilepsy in women; sex differences in brain development; the neural actions of sex and stress hormones and their metabolites; and cellular mechanisms, including brain-derived neurotrophic factor signaling and neuronal-glial interactions. Further attention placed on potential sex differences in epilepsies, comorbidities, and drug effects will enhance therapeutic options and efficacy for all patients with epilepsy. SIGNIFICANCE STATEMENT: Epilepsy is a common neurological disorder that often presents together with various comorbidities. The features of epilepsy and seizure activity as well as comorbid afflictions can vary between men and women. In this review, we discuss sex differences in types of epilepsies, associated comorbidities, pathophysiological mechanisms, and antiepileptic drug efficacy in both clinical patient populations and preclinical animal models.
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Affiliation(s)
- Catherine A Christian
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Doodipala Samba Reddy
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Jamie Maguire
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
| | - Patrick A Forcelli
- Department of Molecular and Integrative Physiology, Neuroscience Program, and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois (C.A.C.); Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas (D.S.R.); Neuroscience Department, Tufts University School of Medicine, Boston, Massachusetts (J.M.); and Departments of Pharmacology and Physiology and Neuroscience, Georgetown University, Washington, D.C. (P.A.F.)
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21
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Crunelli V, Lőrincz ML, McCafferty C, Lambert RC, Leresche N, Di Giovanni G, David F. Clinical and experimental insight into pathophysiology, comorbidity and therapy of absence seizures. Brain 2020; 143:2341-2368. [PMID: 32437558 PMCID: PMC7447525 DOI: 10.1093/brain/awaa072] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/19/2019] [Accepted: 01/31/2020] [Indexed: 12/24/2022] Open
Abstract
Absence seizures in children and teenagers are generally considered relatively benign because of their non-convulsive nature and the large incidence of remittance in early adulthood. Recent studies, however, show that 30% of children with absence seizures are pharmaco-resistant and 60% are affected by severe neuropsychiatric comorbid conditions, including impairments in attention, cognition, memory and mood. In particular, attention deficits can be detected before the epilepsy diagnosis, may persist even when seizures are pharmacologically controlled and are aggravated by valproic acid monotherapy. New functional MRI-magnetoencephalography and functional MRI-EEG studies provide conclusive evidence that changes in blood oxygenation level-dependent signal amplitude and frequency in children with absence seizures can be detected in specific cortical networks at least 1 min before the start of a seizure, spike-wave discharges are not generalized at seizure onset and abnormal cortical network states remain during interictal periods. From a neurobiological perspective, recent electrical recordings and imaging of large neuronal ensembles with single-cell resolution in non-anaesthetized models show that, in contrast to the predominant opinion, cortical mechanisms, rather than an exclusively thalamic rhythmogenesis, are key in driving seizure ictogenesis and determining spike-wave frequency. Though synchronous ictal firing characterizes cortical and thalamic activity at the population level, individual cortico-thalamic and thalamocortical neurons are sparsely recruited to successive seizures and consecutive paroxysmal cycles within a seizure. New evidence strengthens previous findings on the essential role for basal ganglia networks in absence seizures, in particular the ictal increase in firing of substantia nigra GABAergic neurons. Thus, a key feature of thalamic ictogenesis is the powerful increase in the inhibition of thalamocortical neurons that originates at least from two sources, substantia nigra and thalamic reticular nucleus. This undoubtedly provides a major contribution to the ictal decrease in total firing and the ictal increase of T-type calcium channel-mediated burst firing of thalamocortical neurons, though the latter is not essential for seizure expression. Moreover, in some children and animal models with absence seizures, the ictal increase in thalamic inhibition is enhanced by the loss-of-function of the astrocytic GABA transporter GAT-1 that does not necessarily derive from a mutation in its gene. Together, these novel clinical and experimental findings bring about paradigm-shifting views of our understanding of absence seizures and demand careful choice of initial monotherapy and continuous neuropsychiatric evaluation of affected children. These issues are discussed here to focus future clinical and experimental research and help to identify novel therapeutic targets for treating both absence seizures and their comorbidities.
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Affiliation(s)
- Vincenzo Crunelli
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.,Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK
| | - Magor L Lőrincz
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK.,Department of Physiology, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Department of Physiology, Anatomy and Neuroscience, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Cian McCafferty
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Régis C Lambert
- Sorbonne Université, CNRS, INSERM, Neuroscience Paris Seine and Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
| | - Nathalie Leresche
- Sorbonne Université, CNRS, INSERM, Neuroscience Paris Seine and Institut de Biologie Paris Seine (NPS - IBPS), Paris, France
| | - Giuseppe Di Giovanni
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.,Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff, UK
| | - François David
- Cerebral dynamics, learning and plasticity, Integrative Neuroscience and Cognition Center - UMR 8002, Paris, France
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22
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Abstract
Absence seizures are commonly encountered in clinical practice. The diagnosis is usually straightforward in majority of cases. However, it may be challenging in patients with some atypical clinical or EEG features or less common epilepsy syndromes. This narrative review describes the clinical and EEG features, treatment and prognosis of the usual and the unusual epilepsy syndromes associated with absence seizures. Absence status epilepticus is also discussed briefly.
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Affiliation(s)
- Puneet Jain
- Epilepsy Program, Division of Neurology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, M5G1X8, Canada.
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23
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Williams MS, Lecas S, Charpier S, Mahon S. Phase-dependent modulation of cortical and thalamic sensory responses during spike-and-wave discharges. Epilepsia 2020; 61:330-341. [PMID: 31912497 DOI: 10.1111/epi.16422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 12/14/2019] [Accepted: 12/16/2019] [Indexed: 12/29/2022]
Abstract
OBJECTIVE The neuronal underpinnings of impaired consciousness during absence seizures remain largely unknown. Spike-and-wave (SW) activity associated with absences imposes two extremely different states in cortical neurons, which transition from suprathreshold synaptic depolarizations during spike phases to membrane hyperpolarization and electrical silence during wave phases. To investigate whether this rhythmic alternation of neuronal states affects the processing of sensory information during seizures, we examined cortical and thalamic responsiveness to brief sensory stimuli in the different phases of the epileptic cycle. METHODS Electrocorticographic (ECoG) monitoring from the primary somatosensory cortex combined with intracellular recordings of subjacent pyramidal neurons, or extracellular recordings of somatosensory thalamic neurons, were performed in the Genetic Absence Epilepsy Rat From Strasbourg. Sensory stimuli consisted of pulses of compressed air applied to the contralateral whiskers. RESULTS Whisker stimuli delivered during spike phases evoked smaller depolarizing synaptic potentials and fewer action potentials in cortical neurons compared to stimuli occurring during wave phases. This spike-related attenuation of cortical responsiveness was accompanied by a reduced neuronal membrane resistance, likely due to the large increase in synaptic conductance. Sensory-evoked firing in thalamocortical neurons was also decreased during ECoG spikes as compared to wave phases, indicating that time-to-time changes in the thalamocortical volley may also contribute to the variability of cortical responses during seizures. SIGNIFICANCE These findings demonstrate that thalamocortical sensory processing during absence seizures is nonstationary and strongly suggest that the cortical impact of a given environmental stimulus is conditioned by its exact timing relative to the SW cycle. The lack of stability of thalamic and cortical responses along seizures may contribute to impaired conscious sensory perception during absences.
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Affiliation(s)
- Mark S Williams
- Brain and Spine Institute, National Institute of Health and Medical Research Mixed Unit of Research 1127, National Center for Scientific Research Mixed Unit of Research 7225, Pitié-Salpêtrière Hospital, Paris, France
| | - Sarah Lecas
- Brain and Spine Institute, National Institute of Health and Medical Research Mixed Unit of Research 1127, National Center for Scientific Research Mixed Unit of Research 7225, Pitié-Salpêtrière Hospital, Paris, France.,Sorbonne University, Pierre and Marie Curie University, Paris, France
| | - Stéphane Charpier
- Brain and Spine Institute, National Institute of Health and Medical Research Mixed Unit of Research 1127, National Center for Scientific Research Mixed Unit of Research 7225, Pitié-Salpêtrière Hospital, Paris, France.,Sorbonne University, Pierre and Marie Curie University, Paris, France
| | - Séverine Mahon
- Brain and Spine Institute, National Institute of Health and Medical Research Mixed Unit of Research 1127, National Center for Scientific Research Mixed Unit of Research 7225, Pitié-Salpêtrière Hospital, Paris, France
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24
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Ossenblok P, van Houdt P, Colon A, Stroink H, van Luijtelaar G. A network approach to investigate the bi-hemispheric synchrony in absence epilepsy. Clin Neurophysiol 2019; 130:1611-1619. [PMID: 31319290 DOI: 10.1016/j.clinph.2019.05.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/11/2019] [Accepted: 05/22/2019] [Indexed: 11/24/2022]
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25
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Peng YC, Wang S, Zhang Y, Huang LJ, Wang XL, Peng Y. Hsp90β inhibitors prevent GLT-1 degradation but have no beneficial efficacy on absence epilepsy. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2019; 21:905-915. [PMID: 30450970 DOI: 10.1080/10286020.2018.1530989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 09/27/2018] [Accepted: 09/28/2018] [Indexed: 06/09/2023]
Abstract
The loss of glutamate transporter-1 (GLT-1) is associated with temporal lobe epilepsy (TLE). A recent study reported that Hsp90β interacted with GLT-1 and recruited it to 20S proteasome for degradation. Therefore, inhibiting Hsp90β may be a new strategy for treating epilepsy. So far, no studies have shown whether the inhibition of Hsp90β had therapeutic effects on absence epilepsy. Using a model of absence epilepsy, we demonstrated that 17-allylamino-17-demethoxygeldanamycin (17AAG) and Ganetespib (STA9090) had no therapeutic effect. Although this is a negative result, it also has a meaningful exploration value for whether Hsp90 inhibitors have therapeutic effects on other epilepsy types.
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Affiliation(s)
- Yu-Chen Peng
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
| | - Shan Wang
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
| | - Yong Zhang
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
| | - Long-Jian Huang
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
| | - Xiao-Liang Wang
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
| | - Ying Peng
- a State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing 100050 , China
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26
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Brigo F, Striano P, Belcastro V. A reappraisal of atypical absence seizures in children and adults: therapeutic implications. Expert Opin Pharmacother 2019; 20:2115-2120. [PMID: 31446808 DOI: 10.1080/14656566.2019.1656716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Introduction: Atypical absences are generalized epileptic seizures typically affecting children with severe epilepsies and learning difficulties along with other seizure types. Video-EEG is essential for their diagnosis. Recently, atypical absence seizures have been reported as a hallmark of some developmental and epileptic encephalopathies.Areas covered: This is a narrative review of the literature which describes the electroclinical features of atypical seizures, the characteristics of developmental epileptic encephalopathies in which this seizure type can occur, and the evidence supporting the use of individual antiseizure drugs for the treatment of atypical absences.Expert opinion: Treatment of absence seizures typically relies on ethosuximide (ineffective against tonic-clonic seizures), valproate (associated with larger proportion of adverse events), or lamotrigine (less effective than the other two). However, unlike typical absences, atypical absences are usually intractable, persist lifetime, and their prognosis depends on the underlying etiology or associated epilepsy syndrome. Besides efficacy, other relevant factors, such as drug formulation, ease of titration and dosing, and drug interactions, should be considered. Drugs that may worsen epilepsy, cognition and behavior should be avoided. In the vast majority of patients, a polytherapy is required, although usually with limited efficacy. Finally, epilepsy syndromes featuring atypical absences require a multidisciplinary approach.
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Affiliation(s)
- Francesco Brigo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.,Department of Neurology, Franz Tappeiner Hospital, Merano, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, DINOGMI-Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health University of Genoa, "G. Gaslini" Institute, Genova, Italy
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27
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Giuliano L, Fatuzzo D, Mainieri G, Maira G, Elia M, Ferlazzo E, Gasparini S, Nicoletti A, Sofia V, Zappia M. Eyelid myoclonia with absences: Electroclinical features and prognostic factors. Epilepsia 2019; 60:1104-1113. [DOI: 10.1111/epi.15157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/21/2019] [Accepted: 04/15/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Loretta Giuliano
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Daniela Fatuzzo
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Greta Mainieri
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Giulia Maira
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Maurizio Elia
- Unit of Neurology and Clinical Neurophysiopathology Oasi Research Institute ‐ IRCCS Troina Italy
| | - Edoardo Ferlazzo
- Department of Medical and Surgical Sciences “Magna Græcia” University of Catanzaro Catanzaro Italy
| | - Sara Gasparini
- Regional Epilepsy Center “Great Metropolitan Hospital” Reggio Calabria Italy
| | - Alessandra Nicoletti
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Vito Sofia
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
| | - Mario Zappia
- Department G.F. Ingrassia, Section of Neurosciences University of Catania Catania Italy
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28
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Hannan S, Faulkner M, Aristovich K, Avery J, Walker M, Holder D. Imaging fast electrical activity in the brain during ictal epileptiform discharges with electrical impedance tomography. NEUROIMAGE-CLINICAL 2018; 20:674-684. [PMID: 30218899 PMCID: PMC6140294 DOI: 10.1016/j.nicl.2018.09.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/27/2018] [Accepted: 09/02/2018] [Indexed: 12/19/2022]
Abstract
Electrical Impedance Tomography (EIT) is an emerging medical imaging technique which can produce tomographic images of internal impedance changes within an object using non-penetrating surface electrodes. It has previously been used to image impedance changes due to neuronal depolarisation during evoked potentials in the rat somatosensory cortex with a resolution of 2 ms and <200 μm, using an epicortical electrode array. The purpose of this work was to use this technique to elucidate the intracortical spatiotemporal trajectory of ictal spike-and-wave discharges (SWDs), induced by electrical stimulation in an acute rat model of epilepsy, throughout the cerebral cortex. Seizures lasting 16.5 ± 5.3 s with repetitive 2-5 Hz SWDs were induced in five rats anaesthetised with fentanyl-isoflurane. Transfer impedance measurements were obtained during each seizure with a 57-electrode epicortical array by applying 50 μA current at 1.7 kHz to two electrodes and recording voltages from all remaining electrodes. Images were reconstructed from averaged SWD-related impedance traces obtained from EIT measurements in successive seizures. We report the occurrence of reproducible impedance changes during the initial spike phase, which had an early onset in the whisker barrel cortex and spread posteriorly, laterally and ventrally over 20 ms (p < 0.03125, N = 5). These findings, which confirm and extend knowledge of SWD initiation and expression, suggest that EIT is a valuable neuroimaging tool for improving understanding of neural circuits implicated in epileptic phenomena.
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Affiliation(s)
- Sana Hannan
- Department of Medical Physics and Biomedical Engineering, University College London, UK.
| | - Mayo Faulkner
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Kirill Aristovich
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - James Avery
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | | | - David Holder
- Department of Medical Physics and Biomedical Engineering, University College London, UK
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29
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Moshé SL, Galanopoulou AS. Searching for the mechanisms of consciousness in epilepsy. Lancet Neurol 2018; 15:1298-1299. [PMID: 27839635 DOI: 10.1016/s1474-4422(16)30278-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 10/12/2016] [Indexed: 10/20/2022]
Affiliation(s)
- Solomon L Moshé
- Saul R Korey Department of Neurology and Dominick P Purpura Department Neuroscience, Albert Einstein College of Medicine, Kennedy Center, New York 10461, USA; Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Kennedy Center, New York 10461, USA.
| | - Aristea S Galanopoulou
- Saul R Korey Department of Neurology and Dominick P Purpura Department Neuroscience, Albert Einstein College of Medicine, Kennedy Center, New York 10461, USA
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30
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Mazzocchetti C, Striano P, Verrotti A. How to select the appropriate pharmacotherapy for absence seizures in children. Expert Opin Pharmacother 2018; 19:1045-1047. [PMID: 29924667 DOI: 10.1080/14656566.2018.1484902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Chiara Mazzocchetti
- a Department of Pediatrics, San Salvatore Hospital , University of L'Aquila , L'Aquila , Italy
| | - Pasquale Striano
- b Pediatric Neurology and Muscular Diseases Unit, DINOGMI-Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health , University of Genoa, "G. Gaslini" Institute , Genova , Italy
| | - Alberto Verrotti
- a Department of Pediatrics, San Salvatore Hospital , University of L'Aquila , L'Aquila , Italy
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31
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Celli R, Santolini I, Guiducci M, van Luijtelaar G, Parisi P, Striano P, Gradini R, Battaglia G, Ngomba RT, Nicoletti F. The α2δ Subunit and Absence Epilepsy: Beyond Calcium Channels? Curr Neuropharmacol 2018; 15:918-925. [PMID: 28290248 PMCID: PMC5652034 DOI: 10.2174/1570159x15666170309105451] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/16/2017] [Accepted: 03/06/2017] [Indexed: 02/08/2023] Open
Abstract
Background: Spike-wave discharges, underlying absence seizures, are generated within a cortico-thalamo-cortical network that involves the somatosensory cortex, the reticular thalamic nucleus, and the ventrobasal thalamic nuclei. Activation of T-type voltage-sensitive calcium channels (VSCCs) contributes to the pathological oscillatory activity of this network, and some of the first-line drugs used in the treatment of absence epilepsy inhibit T-type calcium channels. The α2δ subunit is a component of high voltage-activated VSCCs (i.e., L-, N-, P/Q-, and R channels) and studies carried out in heterologous expression systems suggest that it may also associate with T channels. The α2δ subunit is also targeted by thrombospondins, which regulate synaptogenesis in the central nervous system. Objective: To discuss the potential role for the thrombospondin/α2δ axis in the pathophysiology of absence epilepsy. Methods: We searched PubMed articles for the terms “absence epilepsy”, “T-type voltage-sensitive calcium channels”, “α2δ subunit”, “ducky mice”, “pregabalin”, “gabapentin”, “thrombospondins”, and included papers focusing this Review's scope. Results: We moved from the evidence that mice lacking the α2δ-2 subunit show absence seizures and α2δ ligands (gabapentin and pregabalin) are detrimental in the treatment of absence epilepsy. This suggests that α2δ may be protective against absence epilepsy via a mechanism that does not involve T channels. We discuss the interaction between thrombospondins and α2δ and its potential relevance in the regulation of excitatory synaptic formation in the cortico-thalamo-cortical network. Conclusion: We speculate on the possibility that the thrombospondin/α2δ axis is critical for the correct functioning of the cortico-thalamo-cortical network, and that abnormalities in this axis may play a role in the pathophysiology of absence epilepsy.
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Affiliation(s)
- Roberta Celli
- I.R.C.C.S. Neuromed, Neuropharmacology Unit, Pozzilli, (IS), Italy
| | - Ines Santolini
- I.R.C.C.S. Neuromed, Neuropharmacology Unit, Pozzilli, (IS), Italy
| | - Michela Guiducci
- Departments of Neurosciences, Mental Health and Sensory Organs, Experimental Medicine, and Physiology and Pharmacology, University Sapienza, Rome, Italy
| | - Gilles van Luijtelaar
- Donders Centre for Cognition, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen. Netherlands
| | - Pasquale Parisi
- Departments of Neurosciences, Mental Health and Sensory Organs, Experimental Medicine, and Physiology and Pharmacology, University Sapienza, Rome, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, "G. Gaslini" Institute, Genova, Italy
| | - Roberto Gradini
- I.R.C.C.S. Neuromed, Neuropharmacology Unit, Pozzilli, (IS), Italy
| | | | - Richard T Ngomba
- University of Lincoln, School of Pharmacy, Lincoln, United Kingdom
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, University Sapienza, Piazzale Aldo Moro, 5, 00185 Rome, Italy
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32
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Wielaender F, James FMK, Cortez MA, Kluger G, Neßler JN, Tipold A, Lohi H, Fischer A. Absence Seizures as a Feature of Juvenile Myoclonic Epilepsy in Rhodesian Ridgeback Dogs. J Vet Intern Med 2017; 32:428-432. [PMID: 29194766 PMCID: PMC5787207 DOI: 10.1111/jvim.14892] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 10/10/2017] [Accepted: 10/31/2017] [Indexed: 01/17/2023] Open
Abstract
Myoclonic epilepsy in Rhodesian Ridgeback (RR) dogs is characterized by myoclonic seizures occurring mainly during relaxation periods, a juvenile age of onset and generalized tonic‐clonic seizures in one‐third of patients. An 8‐month‐old female intact RR was presented for myoclonic seizures and staring episodes that both started at 10 weeks of age. Testing for the DIRAS1 variant indicated a homozygous mutant genotype. Unsedated wireless video‐electroencephalography (EEG) identified frequent, bilaterally synchronous, generalized 4 Hz spike‐and‐wave complexes (SWC) during the staring episodes in addition to the characteristic myoclonic seizures with generalized 4–5 Hz SWC or 4–5 Hz slowing. Photic stimulation did not evoke a photoparoxysmal response. Repeat video‐EEG 2 months after initiation of levetiracetam treatment disclosed a >95% decrease in frequency of myoclonic seizures, and absence seizures were no longer evident. Absence seizures represent another seizure type in juvenile myoclonic epilepsy (JME) in RR dogs, which reinforces its parallels to JME in humans.
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Affiliation(s)
- F Wielaender
- Centre for Clinical Veterinary Medicine, LMU Munich, Munich, Germany
| | - F M K James
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - M A Cortez
- Department of Pediatrics, University of Toronto, Toronto, ON, Canada.,Neurosciences & Mental Health Program, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Toronto, ON, Canada
| | - G Kluger
- Department of Neuropediatrics, Epilepsy Center, Schoen Klinik, Vogtareuth, Germany.,Paracelsus Medical University, Salzburg, Austria
| | - J N Neßler
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - A Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - H Lohi
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki and Folkhalsan Research Centre, Helsinki, Finland
| | - A Fischer
- Centre for Clinical Veterinary Medicine, LMU Munich, Munich, Germany
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Singla S, Sureshbabu S, Razora D, Mittal GK, Peter S, Chindripu S, Gupta P. Electro-clinical expression and pharmaco-therapeutic options in Jeavons syndrome-case report and review of literature. INDIAN JOURNAL OF MEDICAL SPECIALITIES 2017. [DOI: 10.1016/j.injms.2017.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Belcastro V, Giordano L, Pruna D, Peruzzi C, Casellato S, Barca S, Carlone G, Striano P, Verrotti A. Follow-up study of idiopathic generalized epilepsy with associated absence seizure and myoclonic epilepsy of infancy. Epilepsy Res 2017; 136:123-125. [DOI: 10.1016/j.eplepsyres.2017.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/08/2017] [Accepted: 08/05/2017] [Indexed: 10/19/2022]
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Wang Z, Wang Q. Eliminating Absence Seizures through the Deep Brain Stimulation to Thalamus Reticular Nucleus. Front Comput Neurosci 2017; 11:22. [PMID: 28469569 PMCID: PMC5395627 DOI: 10.3389/fncom.2017.00022] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 03/27/2017] [Indexed: 01/19/2023] Open
Abstract
Deep brain stimulation (DBS) can play a crucial role in the modulation of absence seizures, yet relevant biophysical mechanisms are not completely established. In this paper, on the basis of a biophysical mean-field model, we investigate a typical absence epilepsy activity by introducing slow kinetics of GABAB receptors on thalamus reticular nucleus (TRN). We find that the region of spike and slow-wave discharges (SWDs) can be reduced greatly when we add the DBS to TRN. Furthermore, we systematically explore how the corresponding stimulation parameters including frequency, amplitude and positive input duration suppress the SWDs under certain conditions. It is shown that the SWDs can be controlled as key stimulation parameters are suitably chosen. The results in this paper can be helpful for researchers to understand the thalamus stimulation in treating epilepsy patients, and provide theoretical basis for future experimental and clinical studies.
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Affiliation(s)
- Zhihui Wang
- Department of Dynamics and Control, Beihang UniversityBeijing, China
| | - Qingyun Wang
- Department of Dynamics and Control, Beihang UniversityBeijing, China
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Evaluation of deep gray matter volume, cortical thickness and white matter integrity in patients with typical absence epilepsy: a study using voxelwise-based techniques. Neuroradiology 2017; 59:237-245. [DOI: 10.1007/s00234-017-1782-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/02/2017] [Indexed: 11/27/2022]
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Williams MS, Altwegg-Boussac T, Chavez M, Lecas S, Mahon S, Charpier S. Integrative properties and transfer function of cortical neurons initiating absence seizures in a rat genetic model. J Physiol 2016; 594:6733-6751. [PMID: 27311433 DOI: 10.1113/jp272162] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 05/23/2016] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Absence seizures are accompanied by spike-and-wave discharges in cortical electroencephalograms. These complex paroxysmal activities, affecting the thalamocortical networks, profoundly alter cognitive performances and preclude conscious perception. Here, using a well-recognized genetic model of absence epilepsy, we investigated in vivo how information processing was impaired in the ictogenic neurons, i.e. the population of cortical neurons responsible for seizure initiation. In between seizures, ictogenic neurons were more prone to generate bursting activity and their firing response to weak depolarizing events was considerably facilitated compared to control neurons. In the course of seizures, information processing became unstable in ictogenic cells, alternating between an increased and a decreased responsiveness to excitatory inputs, depending on the spike and wave patterns. The state-dependent modulation in the excitability of ictogenic neurons affects their inter-seizure transfer function and their time-to-time responsiveness to incoming inputs during absences. ABSTRACT Epileptic seizures result from aberrant cellular and/or synaptic properties that can alter the capacity of neurons to integrate and relay information. During absence seizures, spike-and-wave discharges (SWDs) interfere with incoming sensory inputs and preclude conscious experience. The Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well-established animal model of absence epilepsy, allows exploration of the cellular basis of this impaired information processing. Here, by combining in vivo electrocorticographic and intracellular recordings from GAERS and control animals, we investigated how the pro-ictogenic properties of seizure-initiating cortical neurons modify their integrative properties and input-output operation during inter-ictal periods and during the spike (S-) and wave (W-) cortical patterns alternating during seizures. In addition to a sustained depolarization and an excessive firing rate in between seizures, ictogenic neurons exhibited a pronounced hyperpolarization-activated depolarization compared to homotypic control neurons. Firing frequency versus injected current relations indicated an increased sensitivity of GAERS cells to weak excitatory inputs, without modifications in the trial-to-trial variability of current-induced firing. During SWDs, the W-component resulted in paradoxical effects in ictogenic neurons, associating an increased membrane input resistance with a reduction in the current-evoked firing responses. Conversely, the collapse of cell membrane resistance during the S-component was accompanied by an elevated current-evoked firing relative to W-sequences, which remained, however, lower compared to inter-ictal periods. These findings show a dynamic modulation of ictogenic neurons' intrinsic properties that may alter inter-seizure cortical function and participate in compromising information processing in cortical networks during absences.
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Affiliation(s)
- Mark S Williams
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Tristan Altwegg-Boussac
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Mario Chavez
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Sarah Lecas
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France.,UPMC Univ Paris 06, F-75005, Paris, France
| | - Séverine Mahon
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Stéphane Charpier
- Sorbonne Universités, UPMC Univ Paris 06, UPMC; INSERM U 1127, CNRS, UMR 7225, Hôpital Pitié-Salpêtrière, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France.,UPMC Univ Paris 06, F-75005, Paris, France
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Ahmadbegi S, Jafarian AA, Aliasl J, Rostami A. Typical Absence Seizure Similarity to "Shokhous" in Iranian Traditional Medicine. IRANIAN RED CRESCENT MEDICAL JOURNAL 2016; 18:e21048. [PMID: 26889388 PMCID: PMC4752727 DOI: 10.5812/ircmj.21048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 07/28/2014] [Accepted: 09/01/2014] [Indexed: 11/23/2022]
Affiliation(s)
- Somaye Ahmadbegi
- Department of Iranian Traditional Medicine, School of Traditional Medicine, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Ali Akbar Jafarian
- Department of Anesthesiology, Research Institute for Islamic and Complementary Medicine (RICM), Iran University of Medical Sciences, Tehran, IR Iran
- Corresponding Author: Ali Akbar Jafarian, Department of Anesthesiology, Research Institute for Islamic and Complementary Medicine (RICM), Iran University of Medical Sciences, Tehran, IR Iran. Tel: +98-2133977966, Fax: +98-2133116726, E-mail:
| | - Jale Aliasl
- Traditional Medicine Clinical Trial Research Center, Shahed University, Tehran, IR Iran
| | - Ali Rostami
- The Research Institute for Islamic and Complementary Medicine, Iran University of Medical Sciences, Tehran, IR Iran
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Neuropsychological impairment in childhood absence epilepsy: Review of the literature. J Neurol Sci 2015; 359:59-66. [DOI: 10.1016/j.jns.2015.10.035] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 10/14/2015] [Accepted: 10/15/2015] [Indexed: 11/22/2022]
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Zhao X, Robinson PA. Generalized seizures in a neural field model with bursting dynamics. J Comput Neurosci 2015; 39:197-216. [PMID: 26282528 DOI: 10.1007/s10827-015-0571-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 07/02/2015] [Accepted: 07/26/2015] [Indexed: 11/27/2022]
Abstract
The mechanisms underlying generalized seizures are explored with neural field theory. A corticothalamic neural field model that has accounted for multiple brain activity phenomena and states is used to explore changes leading to pathological seizure states. It is found that absence seizures arise from instabilities in the system and replicate experimental studies in numerous animal models and clinical studies.
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Affiliation(s)
- X Zhao
- School of Physics, The University of Sydney, Sydney, New South Wales, 2006, Australia.
- Center for Integrative Brain Function, University of Sydney, NSW, 2006, Australia.
- Neurosleep, 431 Glebe Point Rd, Glebe, New South Wales, 2037, Australia.
- Cooperative Research Center for Alertness, Safety, and Productivity, University of Sydney, NSW, 2006, Australia.
| | - P A Robinson
- School of Physics, The University of Sydney, Sydney, New South Wales, 2006, Australia
- Center for Integrative Brain Function, University of Sydney, NSW, 2006, Australia
- Neurosleep, 431 Glebe Point Rd, Glebe, New South Wales, 2037, Australia
- Cooperative Research Center for Alertness, Safety, and Productivity, University of Sydney, NSW, 2006, Australia
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Scicchitano F, van Rijn CM, van Luijtelaar G. Unilateral and Bilateral Cortical Resection: Effects on Spike-Wave Discharges in a Genetic Absence Epilepsy Model. PLoS One 2015; 10:e0133594. [PMID: 26262879 PMCID: PMC4532477 DOI: 10.1371/journal.pone.0133594] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 06/29/2015] [Indexed: 12/28/2022] Open
Abstract
Research Question Recent discoveries have challenged the traditional view that the thalamus is the primary source driving spike-and-wave discharges (SWDs). At odds, SWDs in genetic absence models have a cortical focal origin in the deep layers of the perioral region of the somatosensory cortex. The present study examines the effect of unilateral and bilateral surgical resection of the assumed focal cortical region on the occurrence of SWDs in anesthetized WAG/Rij rats, a well described and validated genetic absence model. Methods Male WAG/Rij rats were used: 9 in the resected and 6 in the control group. EEG recordings were made before and after craniectomy, after unilateral and after bilateral removal of the focal region. Results SWDs decreased after unilateral cortical resection, while SWDs were no longer noticed after bilateral resection. This was also the case when the resected areas were restricted to layers I-IV with layers V and VI intact. Conclusions These results suggest that SWDs are completely abolished after bilateral removal of the focal region, most likely by interference with an intracortical columnar circuit. The evidence suggests that absence epilepsy is a network type of epilepsy since interference with only the local cortical network abolishes all seizures.
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Affiliation(s)
- Francesca Scicchitano
- Department of Health Science, School of Medicine and Surgery, University “Magna Graecia” of Catanzaro, Viale Europa—Germaneto, 88100, Catanzaro, Italy
| | - Clementina M. van Rijn
- Department of Biological Psychology, Donders Centre for Cognition, Donders Institution of Brain, Cognition and Behavior, Radboud University, Nijmegen, The Netherlands
| | - Gilles van Luijtelaar
- Department of Biological Psychology, Donders Centre for Cognition, Donders Institution of Brain, Cognition and Behavior, Radboud University, Nijmegen, The Netherlands
- * E-mail:
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42
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Lebon S, Suarez P, Alija S, Korff CM, Fluss J, Mercati D, Datta AN, Poloni C, Marcoz JP, Campos-Xavier AB, Bonafé L, Roulet-Perez E. When should clinicians search for GLUT1 deficiency syndrome in childhood generalized epilepsies? Eur J Paediatr Neurol 2015; 19:170-5. [PMID: 25532859 DOI: 10.1016/j.ejpn.2014.11.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 11/12/2014] [Accepted: 11/24/2014] [Indexed: 10/24/2022]
Abstract
UNLABELLED GLUT1 deficiency (GLUT1D) has recently been identified as an important cause of generalized epilepsies in childhood. As it is a treatable condition, it is crucial to determine which patients should be investigated. METHODS We analyzed SLC2A1 for mutations in a group of 93 unrelated children with generalized epilepsies. Fasting lumbar puncture was performed following the identification of a mutation. We compared our results with a systematic review of 7 publications of series of patients with generalized epilepsies screened for SLC2A1 mutations. RESULTS We found 2/93 (2.1%) patients with a SLC2A1 mutation. One, carrying a novel de novo deletion had epilepsy with myoclonic-atonic seizures (MAE), mild slowing of head growth, choreiform movements and developmental delay. The other, with a paternally inherited missense mutation, had childhood absence epilepsy with atypical EEG features and paroxysmal exercise-induced dyskinesia (PED) initially misdiagnosed as myoclonic seizures. Out of a total of 1110 screened patients with generalized epilepsies from 7 studies, 2.4% (29/1110) had GLUT1D. This rate was higher (5.6%) among 303 patients with early onset absence epilepsy (EOAE) from 4 studies. About 50% of GLUT1D patients had abnormal movements and 41% a family history of seizures, abnormal movements or both. CONCLUSION GLUT1D is most likely to be found in MAE and in EOAE. The probability of finding GLUT1D in the classical idiopathic generalized epilepsies is very low. Pointers to GLUT1D include an increase in seizures before meals, cognitive impairment, or PED which can easily be overlooked.
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Affiliation(s)
- Sébastien Lebon
- Pediatric Neurology and Neurorehabilitation Unit, Department of Pediatrics, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
| | - Philippe Suarez
- Centre for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland
| | - Semsa Alija
- Centre for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland
| | | | - Joël Fluss
- Child Neurology, University Hospitals, Geneva, Switzerland
| | | | - Alexandre N Datta
- Pediatric Neurology and Development Unit, University Children's Hospital, Basel, Switzerland
| | - Claudia Poloni
- Pediatric Neurology and Neurorehabilitation Unit, Department of Pediatrics, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | | | | | - Luisa Bonafé
- Centre for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland
| | - Eliane Roulet-Perez
- Pediatric Neurology and Neurorehabilitation Unit, Department of Pediatrics, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
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Venzi M, Di Giovanni G, Crunelli V. A critical evaluation of the gamma-hydroxybutyrate (GHB) model of absence seizures. CNS Neurosci Ther 2015; 21:123-40. [PMID: 25403866 PMCID: PMC4335601 DOI: 10.1111/cns.12337] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/13/2014] [Accepted: 09/17/2014] [Indexed: 12/13/2022] Open
Abstract
Typical absence seizures (ASs) are nonconvulsive epileptic events which are commonly observed in pediatric and juvenile epilepsies and may be present in adults suffering from other idiopathic generalized epilepsies. Our understanding of the pathophysiological mechanisms of ASs has been greatly advanced by the availability of genetic and pharmacological models, in particular the γ-hydroxybutyrate (GHB) model which, in recent years, has been extensively used in studies in transgenic mice. GHB is an endogenous brain molecule that upon administration to various species, including humans, induces not only ASs but also a state of sedation/hypnosis. Analysis of the available data clearly indicates that only in the rat does there exist a set of GHB-elicited behavioral and EEG events that can be confidently classified as ASs. Other GHB activities, particularly in mice, appear to be mostly of a sedative/hypnotic nature: thus, their relevance to ASs requires further investigation. At the molecular level, GHB acts as a weak GABA-B agonist, while the existence of a GHB receptor remains elusive. The pre- and postsynaptic actions underlying GHB-elicited ASs have been thoroughly elucidated in thalamus, but little is known about the cellular/network effects of GHB in neocortex, the other brain region involved in the generation of ASs.
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Affiliation(s)
- Marcello Venzi
- Neuroscience DivisionSchool of BioscienceCardiff UniversityCardiffUK
| | - Giuseppe Di Giovanni
- Neuroscience DivisionSchool of BioscienceCardiff UniversityCardiffUK
- Department of Physiology and BiochemistryMalta UniversityMsida, Malta
| | - Vincenzo Crunelli
- Neuroscience DivisionSchool of BioscienceCardiff UniversityCardiffUK
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Do pure absence seizures occur in myoclonic epilepsy of infancy? A case series. Seizure 2015; 24:8-11. [DOI: 10.1016/j.seizure.2014.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/04/2014] [Accepted: 11/07/2014] [Indexed: 11/23/2022] Open
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van Luijtelaar G, Onat FY, Gallagher MJ. Animal models of absence epilepsies: what do they model and do sex and sex hormones matter? Neurobiol Dis 2014; 72 Pt B:167-79. [PMID: 25132554 DOI: 10.1016/j.nbd.2014.08.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 08/05/2014] [Accepted: 08/07/2014] [Indexed: 11/28/2022] Open
Abstract
While epidemiological data suggest a female prevalence in human childhood- and adolescence-onset typical absence epilepsy syndromes, the sex difference is less clear in adult-onset syndromes. In addition, although there are more females than males diagnosed with typical absence epilepsy syndromes, there is a paucity of studies on sex differences in seizure frequency and semiology in patients diagnosed with any absence epilepsy syndrome. Moreover, it is unknown if there are sex differences in the prevalence or expression of atypical absence epilepsy syndromes. Surprisingly, most studies of animal models of absence epilepsy either did not investigate sex differences, or failed to find sex-dependent effects. However, various rodent models for atypical syndromes such as the AY9944 model (prepubertal females show a higher incidence than prepubertal males), BN model (also with a higher prevalence in males) and the Gabra1 deletion mouse in the C57BL/6J strain offer unique possibilities for the investigation of the mechanisms involved in sex differences. Although the mechanistic bases for the sex differences in humans or these three models are not yet known, studies of the effects of sex hormones on seizures have offered some possibilities. The sex hormones progesterone, estradiol and testosterone exert diametrically opposite effects in genetic absence epilepsy and pharmacologically-evoked convulsive types of epilepsy models. In addition, acute pharmacological effects of progesterone on absence seizures during proestrus are opposite to those seen during pregnancy. 17β-Estradiol has anti-absence seizure effects, but it is only active in atypical absence models. It is speculated that the pro-absence action of progesterone, and perhaps also the delayed pro-absence action of testosterone, are mediated through the neurosteroid allopregnanolone and its structural and functional homolog, androstanediol. These two steroids increase extrasynaptic thalamic tonic GABAergic inhibition by selectively targeting neurosteroid-selective subunits of GABAA receptors (GABAARs). Neurosteroids also modulate the expression of GABAAR containing the γ2, α4, and δ subunits. It is hypothesized that differences in subunit expression during pregnancy and ovarian cycle contribute to the opposite effects of progesterone in these two hormonal states.
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Affiliation(s)
- Gilles van Luijtelaar
- Donders Centre of Cognition, Radboud University Nijmegen, Nijmegen, The Netherlands.
| | - Filiz Yilmaz Onat
- Department of Pharmacology, School of Medicine, Marmara University, Istanbul, Turkey
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Chen Y, Parker WD, Wang K. The role of T-type calcium channel genes in absence seizures. Front Neurol 2014; 5:45. [PMID: 24847307 PMCID: PMC4023043 DOI: 10.3389/fneur.2014.00045] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 03/24/2014] [Indexed: 12/05/2022] Open
Abstract
The thalamic relay neurons, reticular thalamic nucleus, and neocortical pyramidal cells form a circuit that sustains oscillatory burst firing, and is regarded as the underlying mechanism of absence seizures. T-type calcium channels play a key role in this circuit. Here, we review the role of T-type calcium channel genes in the development of absence seizures, and emphasize gain or loss of function mutations, and other variations that alter both quantity and quality of transcripts, and methylation status of isoforms of T-type calcium channel proteins might be of equal importance in understanding the pathological mechanism of absence seizures.
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Affiliation(s)
- Yucai Chen
- University of Illinois at Chicago , Peoria, IL , USA
| | | | - Keling Wang
- Hebei Children Hospital , Shijiazhuang , China
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48
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Wang XL, Bao JX, Liang-Shi, Tie-Ma, Deng YC, Zhao G, Swa B, Liu YH. Jeavons syndrome in China. Epilepsy Behav 2014; 32:64-71. [PMID: 24495864 DOI: 10.1016/j.yebeh.2013.12.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Revised: 12/16/2013] [Accepted: 12/16/2013] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Jeavons syndrome (JS) is one of the underreported epileptic syndromes and is characterized by eyelid myoclonia (EM), eye closure-induced seizures or electroencephalography (EEG) paroxysms, and photosensitivity. In the Western populations, it has been reported to be characterized by focal posterior, occipital predominant epileptiform discharges (OPEDs) or frontal predominant epileptiform discharges (FPEDs) followed by generalized EDs in both interictal and ictal EEG recordings. However, it is not clear if there are different clinical manifestations between OPEDs and FPEDs. The clinical and electrographic presentations in the Chinese population are largely unknown. Here, we report the clinical and electroencephalographic features of 50 Chinese patients with JS and evaluate for the presence of different clinical features between patients with OPEDs and patients with FPEDs. METHODS We identified 50 cases who met the Jeavons syndrome criteria from 4230 patients with epilepsy at Xijing Hospital, Xi'an, China from the period of January 2010 to November 2011. These patients underwent long-term 24-hour video-EEG recording. Brain imaging was performed using magnetic resonance imaging (MRI) or computerized tomography (CT). Webster IQ testing was performed to determine intellectual development. We reviewed and described the interictal abnormalities, ictal EEG pattern, and demographic, clinical, and neuroimaging findings of these 50 Chinese patients in Xi'an. We divided the 50 patients into two groups according to the predominance of EDs and analyzed their clinical features. RESULTS Twenty-five of these 50 patients were male. Twenty-two out of 32 patients in the group with FPEDs were male, and 3/18 patients in the group with OPEDs were male. The median age of EMA-EM onset in FPEDs was 8years and that in OPEDs was 5.8years. Eyelid myoclonia occurred in all the 50 patients. Twenty-one out of 32 patients in the group with FPEDs had EM with absences, and 14/32 of them had EM with eyeball rolling up. Two out of 18 patients in the group with OPEDs had EM with absences, and only 1 of 18 had EM with eyeball rolling up. CONCLUSION Eyelid myoclonia with or without absences or JS diagnosis is easily missed and underreported in China. As an IGE, either the frontal or the occipital lobe may initiate generalized spike-and-wave discharges (GSWDs) and generalized seizures (GSs). There may be two subtypes of JS with distinctive clinical and electroencephalogrphic features: a predominantly male group with frontal predominant epileptiform discharges, eyelid myoclonia, and eyes rolling up and a predominantly female group with occipital predominant epileptiform discharges with eyelid myoclonia alone.
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Affiliation(s)
- Xiao-Li Wang
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Jun-Xiang Bao
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an 710032, PR China
| | - Liang-Shi
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Tie-Ma
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Yan-Chun Deng
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Gang Zhao
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Bengwei Swa
- Neuroscience Institute, Kuala Lumpur Hospital, Malaysia.
| | - Yong-Hong Liu
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
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Winkler AS, Wallner B, Friedrich K, Pfausler B, Unterberger I, Matuja W, Jilek-Aall L, Schmutzhard E. A longitudinal study on nodding syndrome--a new African epilepsy disorder. Epilepsia 2013; 55:86-93. [PMID: 24359274 DOI: 10.1111/epi.12483] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2013] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Nodding syndrome (NS), a new epilepsy disorder of sub-Saharan Africa, has only recently been classified. In a study conducted in southern Tanzania in 2005, 62 patients with NS were analyzed in great detail. The present study, a follow-up investigation, was conducted to evaluate the progression of NS over time and to obtain serial electroencephalography (EEG) data. METHODS Of the 62 NS patients, 53 (85.5%), the majority of whom were currently on some form of antiepileptic treatment, could be reevaluated in 2009 with a standardized questionnaire. A subset of these patients (25/53) underwent EEG investigation. RESULTS In patients with "head nodding (HN) only" in 2005, 10 (43.5%) of 23 remained with the same diagnosis, whereas 5 (21.7%) of 23 had developed "HN plus" (i.e., HN and generalized tonic-clonic seizures). Six patients (26.1%) had seizures other than HN only, and two patients (8.7%) had fully recovered. In the "HN plus" group of 2005, 9 (30.0%) of 30 patients remained "HN plus," and 15 patients (50.0%) had seizures other than HN only. Four patients (13.3%) reverted to "HN only," and two patients (6.7%) stopped all seizures. In 11 (44.0%) of 25 patients, electroencephalography (EEG) showed generalized slowing. Six (54.6%) of these 11 abnormal EEG studies further showed generalized epileptiform discharges: (1) ictal electroencephalographic pattern with generalized 2.5 Hz spike and waves in two patients and (2) interictal bursts of 1.5-2 Hz spike and waves in four patients. SIGNIFICANCE This follow-up study confirms that HN represents an epilepsy disorder, possibly of the atypical absence type with dynamic development over time.
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Affiliation(s)
- Andrea S Winkler
- Department of Neurology, Technical University of Munich, Munich, Germany
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