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Xiao L, Yang J, Zhu H, Zhou M, Li J, Liu D, Tang Y, Feng L, Hu S. [ 18F]SynVesT-1 and [ 18F]FDG quantitative PET imaging in the presurgical evaluation of MRI-negative children with focal cortical dysplasia type II. Eur J Nucl Med Mol Imaging 2024; 51:1651-1661. [PMID: 38182838 DOI: 10.1007/s00259-024-06593-1] [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: 08/29/2023] [Accepted: 01/01/2024] [Indexed: 01/07/2024]
Abstract
PURPOSE MRI-negative children with focal cortical dysplasia type II (FCD II) are one of the most challenging cases in surgical epilepsy management. We aimed to utilize quantitative positron emission tomography (QPET) analysis to complement [18F]SynVesT-1 and [18F]FDG PET imaging and facilitate the localization of epileptogenic foci in pediatric MRI-negative FCD II patients. METHODS We prospectively enrolled 17 MRI-negative children with FCD II who underwent [18F]SynVesT-1 and [18F]FDG PET before surgical resection. The QPET scans were analyzed using statistical parametric mapping (SPM) with respect to healthy controls. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of [18F]SynVesT-1 PET, [18F]FDG PET, [18F]SynVesT-1 QPET, and [18F]FDG QPET in the localization of epileptogenic foci were assessed. Additionally, we developed a multivariate prediction model based on dual trace PET/QPET assessment. RESULTS The AUC values of [18F]FDG PET and [18F]SynVesT-1 PET were 0.861 (sensitivity = 94.1%, specificity = 78.2%, PPV = 38.1%, NPV = 98.9%) and 0.908 (sensitivity = 82.4%, specificity = 99.2%, PPV = 93.3%, NPV = 97.5%), respectively. [18F]FDG QPET showed lower sensitivity (76.5%) and NPV (96.6%) but higher specificity (95.0%) and PPV (68.4%) than visual assessment, while [18F]SynVesT-1 QPET exhibited higher sensitivity (94.1%) and NPV (99.1%) but lower specificity (97.5%) and PPV (84.2%). The multivariate prediction model had the highest AUC value (AUC = 0.996, sensitivity = 100.0%, specificity = 96.6%, PPV = 81.0%, NPV = 100%). CONCLUSIONS The multivariate prediction model based on [18F]SynVesT-1 and [18F]FDG PET/QPET assessments holds promise in noninvasively identifying epileptogenic regions in MRI-negative children with FCD II. Furthermore, the combination of visual assessment and QPET may improve the sensitivity and specificity of diagnostic tests in localizing epileptogenic foci and achieving a preferable surgical outcome in MRI-negative FCD II.
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Affiliation(s)
- Ling Xiao
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jinhui Yang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Haoyue Zhu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ming Zhou
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jian Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Dingyang Liu
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yongxiang Tang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China.
| | - Li Feng
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China.
| | - Shuo Hu
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- Key Laboratory of Biological Nanotechnology of National Health Commission, Xiangya Hospital, Central South University, Changsha, Hunan, China.
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Takebayashi Y, Neshige S, Shishido T, Hayashi Y, Segawa A, Nakamori M, Nezu T, Aoki S, Yamazaki Y, Ueno H, Ohshita T, Iida K, Maruyama H. Paradoxical effects of levetiracetam in people with epilepsy with rhythmic epileptiform discharges. Epilepsy Behav 2023; 143:109225. [PMID: 37130461 DOI: 10.1016/j.yebeh.2023.109225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 05/04/2023]
Abstract
OBJECTIVE To elucidate the incidence and risk factors for paradoxical effects (i.e., increased seizure frequency, increased seizure severity, or onset of new seizure types) of levetiracetam (LEV) in people with epilepsy (PWE) and identify the usefulness of electroencephalography (EEG) in predicting these effects. METHODS We examined data for consecutive PWE treated with LEV. All PWE underwent EEG and magnetic resonance imaging (MRI) before LEV administration. We also evaluated the incidence of paradoxical LEV effects and conducted multivariate logistic regression analyses to identify the associated factors. RESULTS In total, 210 (66.2%) of 317 PWEs treated in our department had a history of LEV use. The incidence of paradoxical LEV effects was 5.2% (n = 11) and was significantly associated with a high LEV dose (p = 0.029), high seizure frequency (p = 0.005), temporal lobe epilepsy (p = 0.004), focal awareness seizure (p = 0.004), focal impaired awareness seizure (p = 0.007), spike (p = 0.015), rhythmic epileptiform discharges (REDs; p = 0.003), and MRI-identified focal cortical dysplasia (FCD; p < 0.0001). Multivariate analyses revealed that REDs (odds ratio [OR] = 5.35, p = 0.048, 95% confidence interval [CI]: 1.01-28.21) were independently associated with paradoxical LEV effects. CONCLUSIONS Paradoxical LEV effects occurred in PWE, particularly in those with drug-resistant focal epilepsy. Furthermore, the occurrence of REDs in EEG was an independent factor associated with the paradoxical effects of LEV in PWE.
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Affiliation(s)
- Yoshiko Takebayashi
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Shuichiro Neshige
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan; Epilepsy Center, Hiroshima University Hospital, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan.
| | - Takeo Shishido
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Yuki Hayashi
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Akiko Segawa
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Masahiro Nakamori
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Tomohisa Nezu
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Shiro Aoki
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Yu Yamazaki
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Hiroki Ueno
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Tomohiko Ohshita
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Koji Iida
- Epilepsy Center, Hiroshima University Hospital, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan; Department of Neurosurgery, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
| | - Hirofumi Maruyama
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan; Epilepsy Center, Hiroshima University Hospital, 1-2-3 Kasumi, Minamiku, Hiroshima 734-8551, Japan
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Celdran de Castro A, Nascimento FA, Beltran-Corbellini Á, Toledano R, Garcia-Morales I, Gil-Nagel A, Aledo-Serrano Á. Levetiracetam, from broad-spectrum use to precision prescription: A narrative review and expert opinion. Seizure 2023; 107:121-131. [PMID: 37023625 DOI: 10.1016/j.seizure.2023.03.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/18/2023] [Accepted: 03/22/2023] [Indexed: 04/07/2023] Open
Abstract
Levetiracetam (LEV) is an antiseizure medication (ASM) whose mechanism of action involves the modulation of neurotransmitters release through binding to the synaptic vesicle glycoprotein 2A. It is a broad-spectrum ASM displaying favorable pharmacokinetic and tolerability profiles. Since its introduction in 1999, it has been widely prescribed, becoming the first-line treatment for numerous epilepsy syndromes and clinical scenarios. However, this might have resulted in overuse. Increasing evidence, including the recently published SANAD II trials, suggests that other ASMs are reasonable therapeutic options for generalized and focal epilepsies. Not infrequently, these ASMs show better safety and effectiveness profiles compared to LEV (partially due to the latter's well-known cognitive and behavioral adverse effects, present in up to 20% of patients). Moreover, it has been shown that the underlying etiology of epilepsy is significantly linked to ASMs response in particular scenarios, highlighting the importance of an etiology-based ASM choice. In the case of LEV, it has demonstrated an optimal effectiveness in Alzheimer's disease, Down syndrome, and PCDH19-related epilepsies whereas, in other etiologies such as malformations of cortical development, it may show negligible effects. This narrative review analyzes the current evidence related to the use of LEV for the treatment of seizures. Illustrative clinical scenarios and practical decision-making approaches are also addressed, therefore aiming to define a rational use of this ASM.
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Tang Y, Yu J, Zhou M, Li J, Long T, Li Y, Feng L, Chen D, Yang Z, Huang Y, Hu S. Cortical abnormalities of synaptic vesicle protein 2A in focal cortical dysplasia type II identified in vivo with 18F-SynVesT-1 positron emission tomography imaging. Eur J Nucl Med Mol Imaging 2022; 49:3482-3491. [PMID: 34978594 PMCID: PMC9308579 DOI: 10.1007/s00259-021-05665-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 12/19/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE The loss of synaptic vesicle glycoprotein 2A (SV2A) is well established as the major correlate of epileptogenesis in focal cortical dysplasia type II (FCD II), but this has not been directly tested in vivo. In this positron emission tomography (PET) study with the new tracer 18F-SynVesT-1, we evaluated SV2A abnormalities in patients with FCD II and compared the pattern to 18F-fluorodeoxyglucose (18F-FDG). METHODS Sixteen patients with proven FCD II and 16 healthy controls were recruited. All FCD II patients underwent magnetic resonance imaging (MRI) and static PET imaging with both 18F-SynVesT-1 and 18F-FDG, while the controls underwent MRI and PET with only 18F-SynVesT-1. Visual assessment of PET images was undertaken. The standardized uptake values (SUVs) of 18F-SynVesT-1 were computed for regions of interest (ROIs), along with SUV ratio (SUVr) between ROI and centrum semiovale (white matter). Asymmetry indices (AIs) were analyzed between the lesion and the contralateral hemisphere for intersubject comparisons. RESULTS Lesions in the brains of FCD II patients had significantly reduced 18F-SynVesT-1 uptake compared with contralateral regions, and brains of the controls. 18F-SynVesT-1 PET indicated low lesion uptake in 14 patients (87.5%), corresponding to hypometabolism detected by 18F-FDG PET, with higher accuracy for lesion localization than MRI (43.8%) (P < 0.05). AI analyses demonstrated that in the lesions, SUVr for each of the radiotracers were not significantly different (P > 0.05), and 18F-SynVesT-1 SUVr correlated with that of 18F-FDG across subjects (R2 = 0.41, P = 0.008). Subsequent visual ratings indicated that 18F-SynVesT-1 uptake had a more restricted pattern of reduction than 18F-FDG uptake in FCD II lesions (P < 0.05). CONCLUSION SV2A PET with 18F-SynVesT-1 shows a higher accuracy for the localization of FCD II lesions than MRI and a more restricted pattern of abnormality than 18F-FDG PET.
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Affiliation(s)
- Yongxiang Tang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Jie Yu
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Ming Zhou
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Jian Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Tingting Long
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Yulai Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Li Feng
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Dengming Chen
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China
| | - Zhiquan Yang
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yiyun Huang
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 801 Howard Ave, P.O. Box 208048, New Haven, CT, 06520-8048, USA.
| | - Shuo Hu
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan, China.
- Key Laboratory of Biological Nanotechnology of National Health Commission, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- National Clinical Research Center for Geriatric Disorders (Xiangya), Xiangya Hospital, Central South University, Changsha, Hunan, China.
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Zhang Y, Heylen L, Partoens M, Mills JD, Kaminski RM, Godard P, Gillard M, de Witte PAM, Siekierska A. Connectivity Mapping Using a Novel sv2a Loss-of-Function Zebrafish Epilepsy Model as a Powerful Strategy for Anti-epileptic Drug Discovery. Front Mol Neurosci 2022; 15:881933. [PMID: 35686059 PMCID: PMC9172968 DOI: 10.3389/fnmol.2022.881933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/08/2022] [Indexed: 12/03/2022] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) regulates action potential-dependent neurotransmitter release and is commonly known as the primary binding site of an approved anti-epileptic drug, levetiracetam. Although several rodent knockout models have demonstrated the importance of SV2A for functional neurotransmission, its precise physiological function and role in epilepsy pathophysiology remains to be elucidated. Here, we present a novel sv2a knockout model in zebrafish, a vertebrate with complementary advantages to rodents. We demonstrated that 6 days post fertilization homozygous sv2a–/– mutant zebrafish larvae, but not sv2a+/– and sv2a+/+ larvae, displayed locomotor hyperactivity and spontaneous epileptiform discharges, however, no major brain malformations could be observed. A partial rescue of this epileptiform brain activity could be observed after treatment with two commonly used anti-epileptic drugs, valproic acid and, surprisingly, levetiracetam. This observation indicated that additional targets, besides Sv2a, maybe are involved in the protective effects of levetiracetam against epileptic seizures. Furthermore, a transcriptome analysis provided insights into the neuropathological processes underlying the observed epileptic phenotype. While gene expression profiling revealed only one differentially expressed gene (DEG) between wildtype and sv2a+/– larvae, there were 4386 and 3535 DEGs between wildtype and sv2a–/–, and sv2a+/– and sv2a–/– larvae, respectively. Pathway and gene ontology (GO) enrichment analysis between wildtype and sv2a–/– larvae revealed several pathways and GO terms enriched amongst up- and down-regulated genes, including MAPK signaling, synaptic vesicle cycle, and extracellular matrix organization, all known to be involved in epileptogenesis and epilepsy. Importantly, we used the Connectivity map database to identify compounds with opposing gene signatures compared to the one observed in sv2a–/– larvae, to finally rescue the epileptic phenotype. Two out of three selected compounds rescued electrographic discharges in sv2a–/– larvae, while negative controls did not. Taken together, our results demonstrate that sv2a deficiency leads to increased seizure vulnerability and provide valuable insight into the functional importance of sv2a in the brain in general. Furthermore, we provided evidence that the concept of connectivity mapping represents an attractive and powerful approach in the discovery of novel compounds against epilepsy.
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Affiliation(s)
- Yifan Zhang
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - Lise Heylen
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - Michèle Partoens
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - James D. Mills
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
- Chalfont Centre for Epilepsy, Chalfont St Peter, United Kingdom
| | - Rafal M. Kaminski
- Department of Medicinal Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
- UCB Pharma, Braine-l’Alleud, Belgium
| | | | | | - Peter A. M. de Witte
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
- *Correspondence: Peter A. M. de Witte,
| | - Aleksandra Siekierska
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
- Aleksandra Siekierska,
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Pazarlar BA, Aripaka SS, Petukhov V, Pinborg L, Khodosevich K, Mikkelsen JD. Expression profile of synaptic vesicle glycoprotein 2A, B, and C paralogues in temporal neocortex tissue from patients with temporal lobe epilepsy (TLE). Mol Brain 2022; 15:45. [PMID: 35578248 PMCID: PMC9109314 DOI: 10.1186/s13041-022-00931-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 05/05/2022] [Indexed: 11/10/2022] Open
Abstract
AbstractSynaptic vesicle glycoprotein-2 (SV2) is a family of proteins consisting of SV2A, SV2B, and SV2C. This protein family has attracted attention in recent years after SV2A was shown to be an epileptic drug target and a perhaps a biomarker of synaptic density. So far, the anatomical localization of these proteins in the rodent and human brain have been reported, but co-expression of SV2 genes on a cellular level, their expressions in the human brain, comparison to radioligand binding, any possible regulation in epilepsy are not known. We have here analyzed the expression of SV2 genes in neuronal subtypes in the temporal neocortex in selected specimens by using single nucleus-RNA sequencing, and performed quantitative PCR in populations of temporal lobe epilepsy (TLE) patients and healthy controls. [3H]-UCB-J autoradiography was performed to analyze the correlation between the mRNA transcript and binding capacity to SV2A. Our data showed that the SV2A transcript is expressed in all glutamatergic and GABAergic cortical subtypes, while SV2B expression is restricted to only the glutamatergic neurons and SV2C has very limited expression in a small subgroup of GABAergic interneurons. The level of [3H]-UCB-J binding and the concentration of SV2A mRNA is strongly correlated in each patient, and the expression is lower in the TLE patients. There is no relationship between SV2A expression and age, sex, seizure frequency, duration of epilepsy, or whether patients were recently treated with levetiracetam or not. Collectively, these findings point out a neuronal subtype-specific distribution of the expression of the three SV2 genes, and the lower levels of both radioligand binding and expression further emphasize the significance of these proteins in this disease.
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Eastman CL, Fender JS, Klein P, D'Ambrosio R. Therapeutic Effects of Time-Limited Treatment with Brivaracetam on Posttraumatic Epilepsy after Fluid Percussion Injury in the Rat. J Pharmacol Exp Ther 2021; 379:310-323. [PMID: 34593559 DOI: 10.1124/jpet.121.000585] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 09/28/2021] [Indexed: 11/22/2022] Open
Abstract
Mounting evidence suggests the synaptic vesicle glycoprotein 2A (SV2A) targeted by levetiracetam may contribute to epileptogenesis. Levetiracetam has shown anti-inflammatory, antioxidant, neuroprotective, and possible antiepileptogenic effects in brain injury and seizure/epilepsy models, and a phase 2 study has signaled a possible clinical antiepileptogenic effect. Brivaracetam shows greater affinity and specificity for SV2A than levetiracetam and broader preclinical antiseizure effects. Thus, we assessed the antiepileptogenic/disease-modifying potential of brivaracetam in an etiologically realistic rat posttraumatic epilepsy model optimized for efficient drug testing. Brivaracetam delivery protocols were designed to maintain clinical moderate-to-high plasma levels in young (5-week-old) male Sprague-Dawley rats for 4 weeks. Treatment protocols were rapidly screened in 4-week experiments using small groups of animals to ensure against rigorous testing of futile treatment protocols. The antiepileptogenic effects of brivaracetam treatment initiated 30 minutes, 4 hours, and 8 hours after rostral parasagittal fluid percussion injury (rpFPI) were then compared with vehicle-treated controls in a fully powered blind and randomized 16-week validation. Seizures were evaluated by video-electrocorticography using a 5-electrode epidural montage. Endpoint measures included incidence, frequency, duration, and spread of seizures. Group sizes and recording durations were supported by published power analyses. Three months after treatment ended, rats treated with brivaracetam starting at 4 hours post-FPI (the best-performing protocol) experienced a 38% decrease in overall incidence of seizures, 59% decrease in seizure frequency, 67% decrease in time spent seizing, and a 45% decrease in the proportion of spreading seizures that was independent of duration-based seizure definition. Thus, brivaracetam shows both antiepileptogenic and disease-modifying properties after rpFPI. SIGNIFICANCE STATEMENT: The rpFPI model, which likely incorporates epileptogenic mechanisms operating after human head injury, can be used to efficiently screen investigational treatment protocols and assess antiepileptogenic/disease-modifying effects. Our studies 1) support a role for SV2A in epileptogenesis, 2) suggest that brivaracetam and other drugs targeting SV2A should be considered for human clinical trials of prevention of post-traumatic epilepsy after head injury, and 3) provide data to inform the design of treatment protocols for clinical trials.
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Affiliation(s)
- Clifford L Eastman
- Department of Neurological Surgery, University of Washington, Seattle, Washington (C.L.E., J.S.F., R.D.); and Mid-Atlantic Epilepsy and Sleep Center, Bethesda, Maryland (P.K.)
| | - Jason S Fender
- Department of Neurological Surgery, University of Washington, Seattle, Washington (C.L.E., J.S.F., R.D.); and Mid-Atlantic Epilepsy and Sleep Center, Bethesda, Maryland (P.K.)
| | - Pavel Klein
- Department of Neurological Surgery, University of Washington, Seattle, Washington (C.L.E., J.S.F., R.D.); and Mid-Atlantic Epilepsy and Sleep Center, Bethesda, Maryland (P.K.)
| | - Raimondo D'Ambrosio
- Department of Neurological Surgery, University of Washington, Seattle, Washington (C.L.E., J.S.F., R.D.); and Mid-Atlantic Epilepsy and Sleep Center, Bethesda, Maryland (P.K.)
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8
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Takahashi S, Takechi K, Jozukuri N, Niimura T, Chuma M, Goda M, Zamami Y, Izawa-Ishizawa Y, Imanishi M, Horinouchi Y, Ikeda Y, Tsuchiya K, Yanagawa H, Ishizawa K. Examination of the antiepileptic effects of valacyclovir using kindling mice- search for novel antiepileptic agents by drug repositioning using a large medical information database. Eur J Pharmacol 2021; 902:174099. [PMID: 33910036 DOI: 10.1016/j.ejphar.2021.174099] [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: 01/06/2021] [Revised: 03/31/2021] [Accepted: 04/07/2021] [Indexed: 11/26/2022]
Abstract
Despite the availability of more than 20 clinical antiepileptic drugs, approximately 30% of patients with epilepsy do not respond to antiepileptic drug treatment. Therefore, it is important to develop antiepileptic products that function via novel mechanisms. In the present study, we evaluated data from one of the largest global databases to identify drugs with antiepileptic effects, and subsequently attempted to understand the effect of the combination of antiepileptic drugs and valacyclovir in epileptic seizures using a kindling model. To induce kindling in mice, pentylenetetrazol at a dose of 40 mg/kg was administered once every 48 h. Valacyclovir was orally administered 30 min before antiepileptic drug injection in kindled mice, and behavioral seizures were monitored for 20 min following pentylenetetrazol administration. Additionally, c-Fos expression in the hippocampal dentate gyrus was measured in kindled mice. Valacyclovir showed inhibitory effects on pentylenetetrazol-induced kindled seizures. In addition, simultaneous use of levetiracetam and valacyclovir caused more potent inhibition of seizure activity, and neither valproic acid nor diazepam augmented the anti-seizure effect in kindled mice. Furthermore, kindled mice showed increased c-Fos levels in the dentate gyrus. The increase in c-Fos expression was significantly inhibited by the simultaneous use of levetiracetam and valacyclovir. The findings of the present study indicate that a combination of levetiracetam and valacyclovir had possible anticonvulsive effects on pentylenetetrazol-induced kindled epileptic seizures. These results suggest that valacyclovir may have an antiseizure effect in patients with epilepsy.
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Affiliation(s)
- Shimon Takahashi
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan; Department of Pharmacy, Tokushima University Hospital, Japan
| | - Kenshi Takechi
- Department of Drug Information Analysis, College of Pharmaceutical Sciences, Matsuyama University, Japan.
| | - Natsumi Jozukuri
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan
| | - Takahiro Niimura
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan
| | - Masayuki Chuma
- Department of Hospital Pharmacy & Pharmacology, Asahikawa Medical University & University Hospital, Japan
| | - Mitsuhiro Goda
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan; Clinical Research Center for Developmental Therapeutics, Tokushima University Hospital, Tokushima, Japan
| | - Yoshito Zamami
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan; Department of Pharmacy, Tokushima University Hospital, Japan
| | - Yuki Izawa-Ishizawa
- Department of Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, AWA Support Center, Japan
| | - Masaki Imanishi
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan
| | - Yuya Horinouchi
- Department of Pharmaceutical Care and Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji Yamashiro-cho, Tokushima, 770-8514, Japan
| | - Yasumasa Ikeda
- Department of Pharmacology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Koichiro Tsuchiya
- Department of Medical Pharmacology, Tokushima University Graduate School of Biomedical Sciences, Tokushima, Japan
| | - Hiroaki Yanagawa
- Clinical Research Center for Developmental Therapeutics, Tokushima University Hospital, Tokushima, Japan
| | - Keisuke Ishizawa
- Department of Clinical Pharmacology and Therapeutics, Tokushima University Graduate School of Biomedical Sciences, Japan; Department of Pharmacy, Tokushima University Hospital, Japan
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Contreras-García IJ, Gómez-Lira G, Phillips-Farfán BV, Pichardo-Macías LA, García-Cruz ME, Chávez-Pacheco JL, Mendoza-Torreblanca JG. Synaptic Vesicle Protein 2A Expression in Glutamatergic Terminals Is Associated with the Response to Levetiracetam Treatment. Brain Sci 2021; 11:brainsci11050531. [PMID: 33922424 PMCID: PMC8145097 DOI: 10.3390/brainsci11050531] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/24/2021] [Accepted: 03/24/2021] [Indexed: 12/05/2022] Open
Abstract
Synaptic vesicle protein 2A (SV2A), the target of the antiepileptic drug levetiracetam (LEV), is expressed ubiquitously in all synaptic terminals. Its levels decrease in patients and animal models of epilepsy. Thus, changes in SV2A expression could be a critical factor in the response to LEV. Epilepsy is characterized by an imbalance between excitation and inhibition, hence SV2A levels in particular terminals could also influence the LEV response. SV2A expression was analyzed in the epileptic hippocampus of rats which responded or not to LEV, to clarify if changes in SV2A alone or together with glutamatergic or GABAergic markers may predict LEV resistance. Wistar rats were administered saline (control) or pilocarpine to induce epilepsy. These groups were subdivided into untreated or LEV-treated groups. All epileptic rats were video-monitored to assess their number of seizures. Epileptic rats with an important seizure reduction (>50%) were classified as responders. SV2A, vesicular γ-aminobutyric acid transporter and vesicular glutamate transporter (VGLUT) expression were assessed by immunostaining. SV2A expression was not modified during epilepsy. However, responders showed ≈55% SV2A-VGLUT co-expression in comparison with the non-responder group (≈40%). Thus, SV2A expression in glutamatergic terminals may be important for the response to LEV treatment.
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Affiliation(s)
- Itzel Jatziri Contreras-García
- Área de Neurociencias, Biología de la Reproducción, Unidad Iztapalapa, Universidad Autónoma Metropolitana, Ciudad de México 09340, Mexico;
| | - Gisela Gómez-Lira
- Departamento de Farmacobiología, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México 14330, Mexico;
| | - Bryan Víctor Phillips-Farfán
- Laboratorio de Nutrición Experimental, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
| | - Luz Adriana Pichardo-Macías
- Departamento de Fisiología, Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Ciudad de México 07738, Mexico;
| | - Mercedes Edna García-Cruz
- Laboratorio de Neurociencias, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
| | - Juan Luis Chávez-Pacheco
- Laboratorio de Farmacología, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
| | - Julieta G. Mendoza-Torreblanca
- Laboratorio de Neurociencias, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
- Correspondence: ; Tel.: +52-55-840900 (ext. 1425) or +52-55-21836345
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Yue J, Zhang C, Shi X, Wei Y, Liu L, Liu S, Yang H. Activation of leukocyte immunoglobulin-like receptor B2 signaling pathway in cortical lesions of pediatric patients with focal cortical dysplasia type IIb and tuberous sclerosis complex. Brain Dev 2019; 41:829-838. [PMID: 31495513 DOI: 10.1016/j.braindev.2019.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 07/24/2019] [Accepted: 08/13/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUNDS Focal cortical dysplasia type IIb (FCD IIb) and tuberous sclerosis complex (TSC) are very frequently associated with epilepsy in pediatric patients. Human leukocyte immunoglobulin-like receptor B2 (LILRB2) participates in the process of neurite growth, synaptic plasticity, and inflammatory reaction, suggesting a potential role of LILRB2 in epilepsy. However, little is known about the distribution and expression of LILRB2 in cortical lesions of FCD IIb and cortical tubers of TSC. METHODS In this study, we have described the distribution and expression of LILRB2 signaling pathway in cortical lesions of pediatric patients with FCD IIb (n = 15) and TSC (n = 12) relative to age-matched autopsy control samples (CTX, n = 10), respectively. The protein levels of LILRB2 pathway molecules were assessed by western blotting and immunohistochemistry. The expression pattern was investigated by immunohistochemistry and double labeling experiment. Spearman correlation analysis to explore the correlation between LILRB2 protein level and seizure frequency. RESULTS The protein levels of LILRB2 and its downstream molecules POSH, SHROOM3, ROCK1, ROCK2 were increased in cortices of patients compared to CTX. Protein levels of LILRB2 negatively correlated with the frequency of seizures in FCD IIb and TSC patients, respectively. Moreover, all LILRB2 pathway molecules were strongly expressed in dysmorphic neurons, balloon cells, and giant cells, LILRB2 co-localized with neuron marker and astrocyte marker. CONCLUSION Taken together, the special expression patterns of LILRB2 signaling pathway in cortical lesions of FCD IIb and TSC implies that it may be involved in the process of epilepsy.
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Affiliation(s)
- Jiong Yue
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Chunqing Zhang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xianjun Shi
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Yujia Wei
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Lihong Liu
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Shiyong Liu
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Hui Yang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China.
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11
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Anxiety-like features and spatial memory problems as a consequence of hippocampal SV2A expression. PLoS One 2019; 14:e0217882. [PMID: 31166988 PMCID: PMC6550411 DOI: 10.1371/journal.pone.0217882] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/20/2019] [Indexed: 02/08/2023] Open
Abstract
The Synaptic Vesicle Protein 2A (SV2A) is a transmembrane protein whose presence is reduced both in animal models and in patients with chronic epilepsy. Besides its implication in the epileptic process, the behavioural consequences of the changes in its expression remain unclear. The purpose of our research is to better understand the possible role(s) of this protein through the phenotype of cKO (Grik4 Cre+/-, SV2A lox/lox) mice, male and female, which present a specific decrease of SV2A expression levels in the hippocampal glutamatergic neurons but without any epileptic seizures. In this study, we compare the cKO mice with cHZ (Grik4 Cre+/-, SV2A lox/+) and WT (Grik4 Cre+/+, SV2A lox/lox) mice through a battery of tests, used to evaluate different features: the anxiety-related features (Elevated Plus Maze), the locomotor activity (Activity Chambers), the contextual fear-related memory (Contextual Fear Conditioning), and the spatial memory (Barnes Maze). Our results showed statistically significant differences in the habituation to a new environment, an increase in the anxiety levels and spatial memory deficit in the cHZ and cKO groups, compared to the WT group. No statistically significant differences due to the genotype appeared in the spontaneous locomotor activity or the fear-linked memory. However, sexual differences were observed in this last feature. These results highlight not only an important role of the SV2A protein in the cognitive and anxiety problems typically encountered in epileptic patients, but also a possible role in the symptomatology of other neurodegenerative diseases, such as the Alzheimer’s disease.
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12
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Represa A. Why Malformations of Cortical Development Cause Epilepsy. Front Neurosci 2019; 13:250. [PMID: 30983952 PMCID: PMC6450262 DOI: 10.3389/fnins.2019.00250] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 03/04/2019] [Indexed: 12/13/2022] Open
Abstract
Malformations of cortical development (MCDs), a complex family of rare disorders, result from alterations of one or combined developmental steps, including progenitors proliferation, neuronal migration and differentiation. They are an important cause of childhood epilepsy and frequently associate cognitive deficits and behavioral alterations. Though the physiopathological mechanisms of epilepsy in MCD patients remain poorly elucidated, research during the past decade highlighted the contribution of some factors that will be reviewed in this paper and that include: (i) the genes that caused the malformation, that can be responsible for a significant reduction of inhibitory cells (e.g., ARX gene) or be inducing cell-autonomous epileptogenic changes in affected neurons (e.g., mutations on the mTOR pathway); (ii) the alteration of cortical networks development induced by the malformation that will also involve adjacent or distal cortical areas apparently sane so that the epileptogenic focus might be more extended that the malformation or even localized at distance from it; (iii) the normal developmental processes that would influence and determine the onset of epilepsy in MCD patients, particularly precocious in most of the cases.
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Affiliation(s)
- Alfonso Represa
- INSERM, Institut de Neurobiologie de la Méditerranée, Aix-Marseille University, Marseille, France
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13
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Differential expression of SV2A in hippocampal glutamatergic and GABAergic terminals during postnatal development. Brain Res 2019; 1715:73-83. [PMID: 30905653 DOI: 10.1016/j.brainres.2019.03.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/08/2019] [Accepted: 03/20/2019] [Indexed: 01/15/2023]
Abstract
The function of synaptic vesicle protein 2A (SV2A) has not been clearly identified, although it has an essential role in normal neurotransmission. Changes in SV2A expression have been linked to several diseases that could implicate an imbalance between excitation and inhibition, such as epilepsy. Although it is known that SV2A expression is necessary for survival, SV2A expression and its relationship with γ-aminobutyric acid (GABA) and glutamate neurotransmitter systems along development has not been addressed. This report follows SV2A expression levels in the rat hippocampus and their association with glutamatergic and GABAergic terminals along postnatal development. Total SV2A expression was assessed by real time PCR and western blot, while immunofluorescence was used to identify SV2A protein in the different hippocampal layers and its co-localization with GABA or glutamate vesicular transporters. SV2A was dynamically regulated along development and its association with GABA or glutamate transporters varied in the different hippocampal layers. In the principal cells layers (granular and pyramidal), SV2A protein was preferentially localized to GABAergic terminals, while in the hilus and stratum lucidum SV2A was associated mainly to glutamatergic terminals. Although SV2A was ubiquitously expressed in the entire hippocampus, it established a differential association with excitatory or inhibitory terminals, which could contribute to the maturation of excitatory/inhibitory balance.
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14
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Tokudome K, Shimizu S, Serikawa T, Ohno Y. [Function of synaptic vesicle protein 2A (SV2A) as a novel therapeutic target for epilepsy]. Nihon Yakurigaku Zasshi 2018; 152:275-280. [PMID: 30531097 DOI: 10.1254/fpj.152.275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Epilepsy is a chronic neurologic disease characterized by recurrent seizures, affecting nearly 1% of the population. Synaptic vesicle protein 2A (SV2A) is a membrane protein specifically expressed in synaptic vesicles and is now implicated in the pathogenesis of epileptic disorders. This is because 1) Sv2a-knockout mice exhibit severe seizures, 2) SV2A serves as a specific binding site for certain antiepileptics (e.g., levetiracetam and its analogues) and 3) the SV2A expression changes under various epileptic conditions both in animals (e.g., kindling) and humans (e.g., intractable temporal lobe epilepsy and focal cortical dysplasia). Furthermore, it has been shown that a missense mutation in the SV2A gene caused intractable epilepsy, involuntary movements and developmental retardation, indicating a causative role of SV2A dysfunction in epilepsy. In order to explore the mechanism of SV2A in modulating development of epileptogenesis, we recently developed a novel rat model (Sv2aL174Q rat) carrying a missense mutation (Leu174Gln) in the Sv2a gene. These rats were highly susceptible to the kindling development associated with repeated pentylenetetrazole treatments or electrical stimulations of the amygdala. In addition, the Sv2aL174Q mutation specifically impaired depolarization-induced GABA, but not glutamate, release in the hippocampus and amygdala. All this evidence indicates that the SV2A-GABAergic system plays a crucial role in modulating epileptogenesis and encourages discovery research into the novel antiepileptic agents which enhance the function of the SV2A-GABA system.
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Affiliation(s)
- Kentaro Tokudome
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences
| | - Saki Shimizu
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences
| | - Tadao Serikawa
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences
| | - Yukihiro Ohno
- Department of Pharmacology, Osaka University of Pharmaceutical Sciences
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15
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Contreras-García IJ, Pichardo-Macías LA, Santana-Gómez CE, Sánchez-Huerta K, Ramírez-Hernández R, Gómez-González B, Rocha L, Mendoza Torreblanca JG. Differential expression of synaptic vesicle protein 2A after status epilepticus and during epilepsy in a lithium-pilocarpine model. Epilepsy Behav 2018; 88:283-294. [PMID: 30336420 DOI: 10.1016/j.yebeh.2018.08.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 07/04/2018] [Accepted: 08/17/2018] [Indexed: 11/25/2022]
Abstract
Synaptic vesicle protein 2A (SV2A) has become an attractive target of investigation because of its role in the pathophysiology of epilepsy; SV2A is expressed ubiquitously throughout the brain in all nerve terminals independently of their neurotransmitter content and plays an important but poorly defined role in neurotransmission. Previous studies have shown that modifications in the SV2A protein expression could be a direct consequence of disease severity. Furthermore, these SV2A modifications may depend on specific changes in the nerve tissue following the induction of epilepsy and might be present in both excitatory and inhibitory terminals. Thus, we evaluated SV2A protein expression throughout the hippocampi of lithium-pilocarpine rats after status epilepticus (SE) and during early and late epilepsy. In addition, we determined the γ-aminobutyric acid (GABA)ergic or glutamatergic nature associated with SV2A modifications. Wistar rats were treated with lithium-pilocarpine to induce SE and subsequently were shown to present spontaneous recurrent seizures (SRS). Later, we conducted an exhaustive semi-quantitative analysis of SV2A optical density (OD) throughout the hippocampus by immunohistochemistry. Levels of the SV2A protein were substantially increased in layers formed by principal neurons after SE, mainly because of GABAergic activity. No changes were observed in the early stage of epilepsy. In the late stage of epilepsy, there were minor changes in SV2A OD compared with the robust modifications of SE; however, SV2A protein expression generally showed an increment reaching significant differences in two dendritic layers and hilus, without clear modifications of GABAergic or glutamatergic systems. Our results suggest that the SV2A variations may depend on several factors, such as neuronal activity, and might appear in both excitatory and inhibitory systems depending on the epilepsy stage.
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Affiliation(s)
- Itzel Jatziri Contreras-García
- Instituto Nacional de Pediatría, Subdirección de Medicina experimental, Laboratorio de Neurociencias, México; Posgrado en Biología Experimental, Universidad Autónoma Metropolitana, Unidad Iztapalapa, México
| | - Luz Adriana Pichardo-Macías
- Instituto Nacional de Pediatría, Subdirección de Medicina experimental, Laboratorio de Neurociencias, México; Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Departamento de Fisiología, México
| | - César Emmanuel Santana-Gómez
- Centro de Investigación y de Estudios Avanzados, del Instituto Politécnico Nacional, Sede Sur México, Departamento de Farmacobiología
| | - Karla Sánchez-Huerta
- Instituto Nacional de Pediatría, Subdirección de Medicina experimental, Laboratorio de Neurociencias, México
| | - Rogelio Ramírez-Hernández
- Instituto Nacional de Pediatría, Subdirección de Medicina experimental, Laboratorio de Neurociencias, México
| | | | - Luisa Rocha
- Centro de Investigación y de Estudios Avanzados, del Instituto Politécnico Nacional, Sede Sur México, Departamento de Farmacobiología
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Levetiracetam-Induced Seizure Aggravation in Patients With Focal Cortical Dysplasia. Clin Neuropharmacol 2018; 41:218-221. [PMID: 30234559 DOI: 10.1097/wnf.0000000000000304] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The choice of antiepileptic drug is typically based on seizure type, and there is no evidence for superior effectiveness or potential deterioration of particular antiepileptic drug in specific etiologic subgroups. The aim of the study was to identify etiological factor(s) associated with increased risk of seizure aggravation with levetiracetam (LEV). METHODS A retrospective analysis of 139 patients treated with LEV was performed. Seizure aggravation was defined as a 100% or greater increase in seizures frequency, which occurred within 1 month of drug introduction. RESULTS Five patients who fulfilled the selection criteria were identified. Seizure aggravation occurred with low doses (500-1000 mg) of LEV. In addition to increased frequency and duration, 2 patients developed new seizure types. Withdrawal of LEV resulted in seizure return to background frequency in all patients. Four of 5 patients have distinctive magnetic resonance imaging finding of focal cortical dysplasia. No patients with paradoxical effect of LEV were detected in the idiopathic epilepsy group or other types of symptomatic epilepsies. CONCLUSIONS Our results suggest that LEV may possibly induce seizure exacerbation in a subset of patients with focal cortical dysplasia-related epilepsy, although large studies are needed to establish the relation. Underlying causes of epilepsy could impact the treatment choice because electroclinical semiology might be the "final common pathway" of different epileptogenic mechanisms in diverse etiologies.
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17
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Klein P, Diaz A, Gasalla T, Whitesides J. A review of the pharmacology and clinical efficacy of brivaracetam. Clin Pharmacol 2018; 10:1-22. [PMID: 29403319 PMCID: PMC5783144 DOI: 10.2147/cpaa.s114072] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Brivaracetam (BRV; Briviact) is a new antiepileptic drug (AED) approved for adjunctive treatment of focal (partial-onset) seizures in adults. BRV is a selective, high-affinity ligand for synaptic vesicle 2A (SV2A) with 15- to 30-fold higher affinity than levetiracetam, the first AED acting on SV2A. It has high lipid solubility and rapid brain penetration, with engagement of the target molecule, SV2A, within minutes of administration. BRV has potent broad-spectrum antiepileptic activity in animal models. Phase I studies indicated BRV was well tolerated and showed a favorable pharmacokinetic profile over a wide dose range following single (10–1,000 mg) and multiple (200–800 mg/day) oral dosing. Three pivotal Phase III studies have demonstrated promising efficacy and a good safety and tolerability profile across doses of 50–200 mg/day in the adjunctive treatment of refractory focal seizures. Long-term data indicate that the response to BRV is sustained, with good tolerability and retention rate. BRV is highly effective in patients experiencing secondarily generalized tonic–clonic seizures. Safety data to date suggest a favorable psychiatric adverse effect profile in controlled studies, although limited postmarketing data are available. BRV is easy to use, with no titration and little drug–drug interaction. It can be initiated at target dose with no titration. Efficacy is seen on day 1 of oral use in a significant percentage of patients. Intravenous administration in a 2-minute bolus and 15-minute infusion is well tolerated. Here, we review the pharmacology, pharmacokinetics, and clinical data of BRV.
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Affiliation(s)
- Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA
| | - Anyzeila Diaz
- Neurology Patient Value Unit, UCB Pharma, Smyrna, GA, USA
| | - Teresa Gasalla
- Neurology Patient Value Unit, UCB Pharma, Monheim am Rhein, Germany
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18
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Russo E, Citraro R, Mula M. The preclinical discovery and development of brivaracetam for the treatment of focal epilepsy. Expert Opin Drug Discov 2017; 12:1169-1178. [DOI: 10.1080/17460441.2017.1366985] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Emilio Russo
- Science of Health Department, School of Medicine and Surgery, University of Catanzaro, Catanzaro, Italy
| | - Rita Citraro
- Science of Health Department, School of Medicine and Surgery, University of Catanzaro, Catanzaro, Italy
| | - Marco Mula
- Atkinson Morley Regional Neuroscience Centre, St George’s University Hospitals NHS Foundation Trust, London, UK
- Institute of Medical and Biomedical Education, St George’s University of London, London, UK
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19
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Bartholome O, Van den Ackerveken P, Sánchez Gil J, de la Brassinne Bonardeaux O, Leprince P, Franzen R, Rogister B. Puzzling Out Synaptic Vesicle 2 Family Members Functions. Front Mol Neurosci 2017; 10:148. [PMID: 28588450 PMCID: PMC5438990 DOI: 10.3389/fnmol.2017.00148] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/02/2017] [Indexed: 01/18/2023] Open
Abstract
Synaptic vesicle proteins 2 (SV2) were discovered in the early 80s, but the clear demonstration that SV2A is the target of efficacious anti-epileptic drugs from the racetam family stimulated efforts to improve understanding of its role in the brain. Many functions have been suggested for SV2 proteins including ions or neurotransmitters transport or priming of SVs. Moreover, several recent studies highlighted the link between SV2 and different neuronal disorders such as epilepsy, Schizophrenia (SCZ), Alzheimer's or Parkinson's disease. In this review article, we will summarize our present knowledge on SV2A function(s) and its potential role(s) in the pathophysiology of various brain disorders.
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Affiliation(s)
- Odile Bartholome
- Laboratory of Nervous System Disorders and Therapy, GIGA-Neurosciences, University of LiègeLiège, Belgium
| | | | - Judit Sánchez Gil
- Laboratory of Nervous System Disorders and Therapy, GIGA-Neurosciences, University of LiègeLiège, Belgium
| | | | - Pierre Leprince
- Laboratory of Nervous System Disorders and Therapy, GIGA-Neurosciences, University of LiègeLiège, Belgium
| | - Rachelle Franzen
- Laboratory of Nervous System Disorders and Therapy, GIGA-Neurosciences, University of LiègeLiège, Belgium
| | - Bernard Rogister
- Laboratory of Nervous System Disorders and Therapy, GIGA-Neurosciences, University of LiègeLiège, Belgium.,Department of Neurology, Centre Hospitalier Universitaire de Liège (CHU), University of LiègeLiège, Belgium
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Löscher W, Gillard M, Sands ZA, Kaminski RM, Klitgaard H. Synaptic Vesicle Glycoprotein 2A Ligands in the Treatment of Epilepsy and Beyond. CNS Drugs 2016; 30:1055-1077. [PMID: 27752944 PMCID: PMC5078162 DOI: 10.1007/s40263-016-0384-x] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The synaptic vesicle glycoprotein SV2A belongs to the major facilitator superfamily (MFS) of transporters and is an integral constituent of synaptic vesicle membranes. SV2A has been demonstrated to be involved in vesicle trafficking and exocytosis, processes crucial for neurotransmission. The anti-seizure drug levetiracetam was the first ligand to target SV2A and displays a broad spectrum of anti-seizure activity in various preclinical models. Several lines of preclinical and clinical evidence, including genetics and protein expression changes, support an important role of SV2A in epilepsy pathophysiology. While the functional consequences of SV2A ligand binding are not fully elucidated, studies suggest that subsequent SV2A conformational changes may contribute to seizure protection. Conversely, the recently discovered negative SV2A modulators, such as UCB0255, counteract the anti-seizure effect of levetiracetam and display procognitive properties in preclinical models. More broadly, dysfunction of SV2A may also be involved in Alzheimer's disease and other types of cognitive impairment, suggesting potential novel therapies for levetiracetam and its congeners. Furthermore, emerging data indicate that there may be important roles for two other SV2 isoforms (SV2B and SV2C) in the pathogenesis of epilepsy, as well as other neurodegenerative diseases. Utilization of recently developed SV2A positron emission tomography ligands will strengthen and reinforce the pharmacological evidence that SV2A is a druggable target, and will provide a better understanding of its role in epilepsy and other neurological diseases, aiding in further defining the full therapeutic potential of SV2A modulation.
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Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, 30559, Hannover, Germany.
- Center for Systems Neuroscience, Hannover, Germany.
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Tokudome K, Okumura T, Terada R, Shimizu S, Kunisawa N, Mashimo T, Serikawa T, Sasa M, Ohno Y. A Missense Mutation of the Gene Encoding Synaptic Vesicle Glycoprotein 2A (SV2A) Confers Seizure Susceptibility by Disrupting Amygdalar Synaptic GABA Release. Front Pharmacol 2016; 7:210. [PMID: 27471467 PMCID: PMC4943941 DOI: 10.3389/fphar.2016.00210] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 06/30/2016] [Indexed: 12/14/2022] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) is specifically expressed in the membranes of synaptic vesicles and modulates action potential-dependent neurotransmitter release. To explore the role of SV2A in the pathogenesis of epileptic disorders, we recently generated a novel rat model (Sv2aL174Q rat) carrying a missense mutation of the Sv2a gene and showed that the Sv2aL174Q rats were hypersensitive to kindling development (Tokudome et al., 2016). Here, we further conducted behavioral and neurochemical studies to clarify the pathophysiological mechanisms underlying the seizure vulnerability in Sv2aL174Q rats. Sv2aL174Q rats were highly susceptible to pentylenetetrazole (PTZ)-induced seizures, yielding a significantly higher seizure scores and seizure incidence than the control animals. Brain mapping analysis of Fos expression, a biological marker of neural excitation, revealed that the seizure threshold level of PTZ region-specifically elevated Fos expression in the amygdala in Sv2aL174Q rats. In vivo microdialysis study showed that the Sv2aL174Q mutation preferentially reduced high K+ (depolarization)-evoked GABA release, but not glutamate release, in the amygdala. In addition, specific control of GABA release by SV2A was supported by its predominant expression in GABAergic neurons, which were co-stained with antibodies against SV2A and glutamate decarboxylase 1. The present results suggest that dysfunction of SV2A by the missense mutation elevates seizure susceptibility in rats by preferentially disrupting synaptic GABA release in the amygdala, illustrating the crucial role of amygdalar SV2A-GABAergic system in epileptogenesis.
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Affiliation(s)
- Kentaro Tokudome
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Takahiro Okumura
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Ryo Terada
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Saki Shimizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Naofumi Kunisawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
| | - Tomoji Mashimo
- Institute of Laboratory Animals, Graduate School of Medicine, Kyoto UniversityKyoto, Japan; Institute of Experimental Animal Sciences, Graduate School of Medicine, Osaka UniversityOsaka, Japan
| | - Tadao Serikawa
- Laboratory of Pharmacology, Osaka University of Pharmaceutical SciencesOsaka, Japan; Institute of Laboratory Animals, Graduate School of Medicine, Kyoto UniversityKyoto, Japan
| | | | - Yukihiro Ohno
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences Osaka, Japan
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Paradoxical Effect of Levetiracetam in Newly Diagnosed Type II Focal Cortical Dysplasia. Clin Neuropharmacol 2016; 39:265-8. [PMID: 27404737 DOI: 10.1097/wnf.0000000000000171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A paradoxical effect of antiepileptic drugs was defined as an increased seizure frequency or severity occurring shortly after introducing a drug considered effective for that kind of epilepsy. In addition, this effect should occur at nontoxic drug serum levels. So far, pathophysiological mechanisms underlying this phenomenon have not been clarified. Recent evidence suggests that the variability of drug effects may depend on precise intrinsic properties of dynamic networks involving the drug and its binding site. Although several reports of paradoxical seizure exacerbation have been reported for levetiracetam (LEV), a possible association with focal cortical dysplasia has never been described nor investigated. In this report, we document a paradoxical effect induced by LEV monotherapy in a patient with type II focal cortical dysplasia at LEV serum levels within the therapeutic range. A hint of pathophysiological hypothesis underlying this potential relationship will be also suggested.
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Synaptic vesicle glycoprotein 2A (SV2A) regulates kindling epileptogenesis via GABAergic neurotransmission. Sci Rep 2016; 6:27420. [PMID: 27265781 PMCID: PMC4893657 DOI: 10.1038/srep27420] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/18/2016] [Indexed: 02/08/2023] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) is a prototype synaptic vesicle protein regulating action potential-dependent neurotransmitters release. SV2A also serves as a specific binding site for certain antiepileptics and is implicated in the treatment of epilepsy. Here, to elucidate the role of SV2A in modulating epileptogenesis, we generated a novel rat model (Sv2aL174Q rat) carrying a Sv2a-targeted missense mutation (L174Q) and analyzed its susceptibilities to kindling development. Although animals homozygous for the Sv2aL174Q mutation exhibited normal appearance and development, they are susceptible to pentylenetetrazole (PTZ) seizures. In addition, development of kindling associated with repeated PTZ treatments or focal stimulation of the amygdala was markedly facilitated by the Sv2aL174Q mutation. Neurochemical studies revealed that the Sv2aL174Q mutation specifically reduced depolarization-induced GABA, but not glutamate, release in the hippocampus without affecting basal release or the SV2A expression level in GABAergic neurons. In addition, the Sv2aL174Q mutation selectively reduced the synaptotagmin1 (Syt1) level among the exocytosis-related proteins examined. The present results demonstrate that dysfunction of SV2A due to the Sv2aL174Q mutation impairs the synaptic GABA release by reducing the Syt1 level and facilitates the kindling development, illustrating the crucial role of SV2A-GABA system in modulating kindling epileptogenesis.
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Synaptic vesicle protein2A decreases in amygdaloid-kindling pharmcoresistant epileptic rats. ACTA ACUST UNITED AC 2015; 35:716-722. [PMID: 26489628 DOI: 10.1007/s11596-015-1496-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 07/01/2015] [Indexed: 10/22/2022]
Abstract
Synaptic vesicle protein 2A (SV2A) involvement has been reported in the animal models of epilepsy and in human intractable epilepsy. The difference between pharmacosensitive epilepsy and pharmacoresistant epilepsy remains poorly understood. The present study aimed to observe the hippocampus SV2A protein expression in amygdale-kindling pharmacoresistant epileptic rats. The pharmacosensitive epileptic rats served as control. Amygdaloid-kindling model of epilepsy was established in 100 healthy adult male Sprague-Dawley rats. The kindled rat model of epilepsy was used to select pharmacoresistance by testing their seizure response to phenytoin and phenobarbital. The selected pharmacoresistant rats were assigned to a pharmacoresistant epileptic group (PRE group). Another 12 pharmacosensitive epileptic rats (PSE group) served as control. Immunohistochemistry, real-time PCR and Western blotting were used to determine SV2A expression in the hippocampus tissue samples from both the PRE and the PSE rats. Immunohistochemistry staining showed that SV2A was mainly accumulated in the cytoplasm of the neurons, as well as along their dendrites throughout all subfields of the hippocampus. Immunoreactive staining level of SV2A-positive cells was 0.483 ± 0.304 in the PRE group and 0.866 ± 0.090 in the PSE group (P < 0.05). Real-time PCR analysis demonstrated that 2(-ΔΔCt) value of SV2A mRNA was 0.30 ± 0.43 in the PRE group and 0.76 ± 0.18 in the PSE group (P < 0.05). Western blotting analysis obtained the similar findings (0.27 ± 0.21 versus 1.12 ± 0.21, P < 0.05). PRE rats displayed a significant decrease of SV2A in the brain. SV2A may be associated with the pathogenesis of intractable epilepsy of the amygdaloid-kindling rats.
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Correa-Basurto J, Cuevas-Hernández RI, Phillips-Farfán BV, Martínez-Archundia M, Romo-Mancillas A, Ramírez-Salinas GL, Pérez-González ÓA, Trujillo-Ferrara J, Mendoza-Torreblanca JG. Identification of the antiepileptic racetam binding site in the synaptic vesicle protein 2A by molecular dynamics and docking simulations. Front Cell Neurosci 2015; 9:125. [PMID: 25914622 PMCID: PMC4392693 DOI: 10.3389/fncel.2015.00125] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/17/2015] [Indexed: 01/21/2023] Open
Abstract
Synaptic vesicle protein 2A (SV2A) is an integral membrane protein necessary for the proper function of the central nervous system and is associated to the physiopathology of epilepsy. SV2A is the molecular target of the anti-epileptic drug levetiracetam and its racetam analogs. The racetam binding site in SV2A and the non-covalent interactions between racetams and SV2A are currently unknown; therefore, an in silico study was performed to explore these issues. Since SV2A has not been structurally characterized with X-ray crystallography or nuclear magnetic resonance, a three-dimensional (3D) model was built. The model was refined by performing a molecular dynamics simulation (MDS) and the interactions of SV2A with the racetams were determined by docking studies. A reliable 3D model of SV2A was obtained; it reached structural equilibrium during the last 15 ns of the MDS (50 ns) with remaining structural motions in the N-terminus and long cytoplasmic loop. The docking studies revealed that hydrophobic interactions and hydrogen bonds participate importantly in ligand recognition within the binding site. Residues T456, S665, W666, D670 and L689 were important for racetam binding within the trans-membrane hydrophilic core of SV2A. Identifying the racetam binding site within SV2A should facilitate the synthesis of suitable radio-ligands to study treatment response and possibly epilepsy progression.
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Affiliation(s)
- José Correa-Basurto
- Laboratorio de Modelado Molecular y Diseño de fármacos, Departamento de Bioquímica de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México City Mexico
| | - Roberto I Cuevas-Hernández
- Laboratorio de Modelado Molecular y Diseño de fármacos, Departamento de Bioquímica de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México City Mexico
| | - Bryan V Phillips-Farfán
- Laboratorio de Nutrición Experimental, Laboratorio de Oncología Experimental and Laboratorio de Neuroquímica, Instituto Nacional de Pediatría, México City Mexico
| | - Marlet Martínez-Archundia
- Laboratorio de Modelado Molecular y Diseño de fármacos, Departamento de Bioquímica de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México City Mexico
| | - Antonio Romo-Mancillas
- División de Estudios de Posgrado, Facultad de Química, Universidad Autónoma de Querétaro, Santiago de Querétaro Mexico
| | - Gema L Ramírez-Salinas
- Laboratorio de Modelado Molecular y Diseño de fármacos, Departamento de Bioquímica de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México City Mexico
| | - Óscar A Pérez-González
- Laboratorio de Nutrición Experimental, Laboratorio de Oncología Experimental and Laboratorio de Neuroquímica, Instituto Nacional de Pediatría, México City Mexico
| | - José Trujillo-Ferrara
- Laboratorio de Modelado Molecular y Diseño de fármacos, Departamento de Bioquímica de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México City Mexico
| | - Julieta G Mendoza-Torreblanca
- Laboratorio de Nutrición Experimental, Laboratorio de Oncología Experimental and Laboratorio de Neuroquímica, Instituto Nacional de Pediatría, México City Mexico
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Correlation between clinical and histologic findings in the human neonatal hippocampus after perinatal asphyxia. J Neuropathol Exp Neurol 2014; 73:324-34. [PMID: 24607964 DOI: 10.1097/nen.0000000000000056] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hypoxic ischemic encephalopathy after perinatal asphyxia is a major cause of mortality and morbidity in infants. Here, we evaluated pathologic changes in the hippocampi of a cohort of 16 deceased full-term asphyxiated infants who died from January 2000 to January 2009. Histochemical and immunocytochemical results for glial and neuronal cells were compared between cases with or without seizures and to adult and sudden infant death syndrome cases (n = 3 each). All asphyxiated infants displayed neuronal cell damage and reactive glial changes. Strong aquaporin-4 immunoreactivity was seen on astroglial cells within hippocampi in 50% of cases. In patients with seizures, the expression of metabotropic glutamate receptors was increased in glial cells. Cases with seizures displayed increased microglial activation and greater expression of the inflammatory markers interleukin 1β and complement 1q compared with those in cases without seizures. All cases with seizures displayed alterations in the blood-brain barrier, as assessed by immunohistochemistry for albumin. These findings confirm the complex cascade of cellular and molecular changes occurring in the human neonatal hippocampus after perinatal asphyxia. These changes may contribute to seizure development leading to secondary brain damage. These data may aid in the development of therapeutic targets for neonatal seizures.
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27
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Crèvecœur J, Kaminski RM, Rogister B, Foerch P, Vandenplas C, Neveux M, Mazzuferi M, Kroonen J, Poulet C, Martin D, Sadzot B, Rikir E, Klitgaard H, Moonen G, Deprez M. Expression pattern of synaptic vesicle protein 2 (SV2) isoforms in patients with temporal lobe epilepsy and hippocampal sclerosis. Neuropathol Appl Neurobiol 2014; 40:191-204. [DOI: 10.1111/nan.12054] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 04/17/2013] [Indexed: 11/29/2022]
Affiliation(s)
- J. Crèvecœur
- Laboratory of Neuropathology; GIGA-Neurosciences; University of Liege; Liege Belgium
- Laboratory of Developmental Neurobiology; GIGA-Neurosciences; University of Liege; Liege Belgium
| | | | - B. Rogister
- Laboratory of Developmental Neurobiology; GIGA-Neurosciences; University of Liege; Liege Belgium
- Laboratory of Developmental Neurobiology; GIGA-Development; Stem Cells and Regenerative Medicine; University of Liege; Liege Belgium
- Departement of Neurology; CHU; University of Liege; Liege Belgium
| | - P. Foerch
- UCB Pharma; CNS Research; Braine-l'Alleud Belgium
| | | | - M. Neveux
- UCB Pharma; CNS Research; Braine-l'Alleud Belgium
| | - M. Mazzuferi
- UCB Pharma; CNS Research; Braine-l'Alleud Belgium
| | - J. Kroonen
- Unit of Human Genetics; GIGA Research Center; University of Liege; Liege Belgium
| | - C. Poulet
- Unit of Human Genetics; GIGA Research Center; University of Liege; Liege Belgium
| | - D. Martin
- Department of Neurosurgery; CHU; University of Liege; Liege Belgium
| | - B. Sadzot
- Departement of Neurology; CHU; University of Liege; Liege Belgium
| | - E. Rikir
- Departement of Neurology; CHU; University of Liege; Liege Belgium
| | - H. Klitgaard
- UCB Pharma; CNS Research; Braine-l'Alleud Belgium
| | - G. Moonen
- Laboratory of Developmental Neurobiology; GIGA-Neurosciences; University of Liege; Liege Belgium
- Departement of Neurology; CHU; University of Liege; Liege Belgium
| | - M. Deprez
- Laboratory of Neuropathology; GIGA-Neurosciences; University of Liege; Liege Belgium
- Laboratory of Developmental Neurobiology; GIGA-Neurosciences; University of Liege; Liege Belgium
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28
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Mendoza-Torreblanca JG, Vanoye-Carlo A, Phillips-Farfán BV, Carmona-Aparicio L, Gómez-Lira G. Synaptic vesicle protein 2A: basic facts and role in synaptic function. Eur J Neurosci 2013; 38:3529-39. [DOI: 10.1111/ejn.12360] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 08/09/2013] [Accepted: 08/17/2013] [Indexed: 10/26/2022]
Affiliation(s)
| | | | | | | | - Gisela Gómez-Lira
- Department of Pharmacobiology; Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional; Calzada de los Tenorios 235 Col. Granjas Coapa C.P. 14330 D. F., Mexico
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29
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Kang JQ, Barnes G. A common susceptibility factor of both autism and epilepsy: functional deficiency of GABA A receptors. J Autism Dev Disord 2013; 43:68-79. [PMID: 22555366 DOI: 10.1007/s10803-012-1543-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Autism and epilepsy are common childhood neurological disorders with a great heterogeneity of clinical phenotypes as well as risk factors. There is a high co-morbidity of autism and epilepsy. The neuropathology of autism and epilepsy has similar histology implicating the processes of neurogenesis, neural migration, programmed cell death, and neurite outgrowth. Genetic advances have identified multiple molecules that participate in neural development, brain network connectivity, and synaptic function which are involved in the pathogenesis of autism and epilepsy. Mutations in GABA(A) receptor subunit have been frequently associated with epilepsy, autism, and other neuropsychiatric disorders. In this paper, we address the hypothesis that functional deficiency of GABAergic signaling is a potential common molecular mechanism underpinning the co-morbidity of autism and epilepsy.
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Affiliation(s)
- Jing-Qiong Kang
- Department of Neurology, Vanderbilt University Medical Center, 465 21st Ave, Nashville, TN 37232-8552, USA.
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Iyer A, Prabowo A, Anink J, Spliet WGM, van Rijen PC, Aronica E. Cell injury and premature neurodegeneration in focal malformations of cortical development. Brain Pathol 2013; 24:1-17. [PMID: 23586324 DOI: 10.1111/bpa.12060] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 03/26/2013] [Indexed: 12/17/2022] Open
Abstract
Several lines of evidence suggest that cell injury may occur in malformations of cortical development associated with epilepsy. Moreover, recent studies support the link between neurodevelopmental and neurodegenerative mechanisms. We evaluated a series of focal cortical dysplasia (FCD, n=26; type I and II) and tuberous sclerosis complex (TSC, n=6) cases. Sections were processed for terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end labeling (TUNEL) labeling and immunohistochemistry using markers for the evaluation of apoptosis signaling pathways and neurodegeneration-related proteins/pathways. In both FCD II and TSC specimens, we observed significant increases in both TUNEL-positive and caspase-3-positive cells compared with controls and FCD I. Expression of β-amyloid precursor protein was observed in neuronal soma and processes in FCD II and TSC. In these specimens, we also observed an abnormal expression of death receptor-6. Immunoreactivity for phosphorylated tau was only found in older patients with FCD II and TSC. In these cases, prominent nuclear/cytoplasmic p62 immunoreactivity was detected in both dysmorphic neurons and balloon/giant cells. Our data provide evidence of complex, but similar, mechanisms of cell injury in focal malformations of cortical development associated with mammalian target of rapamycin pathway hyperactivation, with prominent induction of apoptosis-signaling pathways and premature activation of mechanisms of neurodegeneration.
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Affiliation(s)
- Anand Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Iyer A, van Scheppingen J, Anink J, Milenkovic I, Kovács GG, Aronica E. Developmental patterns of DR6 in normal human hippocampus and in Down syndrome. J Neurodev Disord 2013; 5:10. [PMID: 23618225 PMCID: PMC3666921 DOI: 10.1186/1866-1955-5-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 04/04/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Death receptor 6 (DR6) is highly expressed in the human brain: it has been shown to induce axon pruning and neuron death via distinct caspases and to mediate axonal degeneration through binding to N-terminal β amyloid precursor protein (N-APP). METHODS We investigated the expression of DR6 during prenatal and postnatal development in human hippocampus and temporal cortex by immunocytochemistry and Western blot analysis (118 normal human brain specimens; 9 to 41 gestational weeks; 1 day to 7 months postnatally; 3 to 91 years). To investigate the role of N-APP/DR6/caspase 6 pathway in the development of hippocampal Alzheimer's disease (AD)-associated pathology, we examined DR6 immunoreactivity (IR) in the developing hippocampus from patients with Down syndrome (DS; 48 brain specimens; 14 to 41 gestational weeks; 7 days to 8 months postnatally; 15 to 64 years) and in adults with DS and AD. RESULTS DR6 was highly expressed in human adult hippocampus and temporal cortex: we observed consistent similar temporal and spatial expression in both control and DS brain. Western blot analysis of total homogenates of temporal cortex and hippocampus showed developmental regulation of DR6. In the hippocampus, DR6 IR was first apparent in the stratum lacunosum-moleculare at 16 weeks of gestation, followed by stratum oriens, radiatum, pyramidale (CA1 to CA4) and molecular layer of the dentate gyrus between 21 and 23 gestational weeks, reaching a pattern similar to adult hippocampus around birth. Increased DR6 expression in dystrophic neurites was detected focally in a 15-year-old DS patient. Abnormal DR6 expression pattern, with increased expression within dystrophic neurites in and around amyloid plaques was observed in adult DS patients with widespread AD-associated neurodegeneration and was similar to the pattern observed in AD hippocampus. Double-labeling experiments demonstrated the colocalization, in dystrophic neurites, of DR6 with APP. We also observed colocalization with hyper-phosphorylated Tau and with caspase 6 (increased in hippocampus with AD pathology) in plaque-associated dystrophic neurites and within the white matter. CONCLUSIONS These findings demonstrate a developmental regulation of DR6 in human hippocampus and suggest an abnormal activation of the N-APP/DR6/caspase 6 pathway, which can contribute to initiation or progression of hippocampal AD-associated pathology.
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Affiliation(s)
- Anand Iyer
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Jasper Anink
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands
| | - Ivan Milenkovic
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Gabor G Kovács
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, AZ 1105, The Netherlands.,SEIN - Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
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Abstract
BACKGROUND Neonatal seizures can result in chronic epilepsy and long-term behavioral and cognitive deficits. Levetiracetam (LEV), an antiepileptic drug that binds to the synaptic vesicle protein 2A (SV2A), has been increasingly used off-label for the therapy of neonatal seizures. Preclinical data regarding the acute or long-term efficacy of LEV are lacking. METHODS We tested the anticonvulsant efficacy of LEV in a rat model of hypoxia-induced neonatal seizures. In addition, we evaluated the protective effects of postnatal day (P)10 LEV treatment on later-life kainic acid (KA)-induced seizure susceptibility and seizure-induced neuronal injury. Western blot and immunohistochemistry were used to assess the developmental regulation of SV2A in the rat and human brain. RESULTS LEV pretreatment at P10 significantly decreased the cumulative duration of behavioral and electrographic seizures at both 25 and 50 mg/kg. At P40, KA-induced seizures and neuronal loss were significantly diminished in rats previously treated with LEV. LEV target SV2A is present in both neonatal rat and human brain and increases steadily to adulthood. CONCLUSION LEV suppressed acute seizures induced by perinatal hypoxia and diminished later-life seizure susceptibility and seizure-induced neuronal injury, providing evidence for disease modification. These results support consideration of a clinical trial of LEV in neonatal seizures.
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33
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Hanaya R, Hosoyama H, Sugata S, Tokudome M, Hirano H, Tokimura H, Kurisu K, Serikawa T, Sasa M, Arita K. Low distribution of synaptic vesicle protein 2A and synaptotagimin-1 in the cerebral cortex and hippocampus of spontaneously epileptic rats exhibiting both tonic convulsion and absence seizure. Neuroscience 2012; 221:12-20. [DOI: 10.1016/j.neuroscience.2012.06.058] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 06/25/2012] [Accepted: 06/25/2012] [Indexed: 10/28/2022]
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Upregulated expression of voltage-gated sodium channel Nav1.3 in cortical lesions of patients with focal cortical dysplasia type IIb. Neuroreport 2012; 23:407-11. [PMID: 22494998 DOI: 10.1097/wnr.0b013e328351db48] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Focal cortical dysplasia (FCD) is one of the causes of intractable epilepsy in humans. Cytomegalic neurons, not balloon cells, are considered to be the putative generators of epileptic activity in FCD type IIb (FCDIIb). Voltage-gated sodium channel III α-isoforms (Nav1.3) play crucial roles in the initiation and propagation of action potentials and are important regulators of neuronal excitability. Here, we examined 12 FCDIIb surgical specimens from patients undergoing surgery for epilepsy and used age-matched normal control cortical tissue (CTX) from 10 autopsy samples as controls. Using reverse transcription-PCR and western blot techniques, we found that the mRNA and protein levels of Nav1.3 were clearly upregulated in FCDIIb surgical specimens compared with the controls (CTX). Results of immunohistochemistry analyses demonstrated that Nav1.3 immunoreactivity was widely present in FCDIIb lesion tissue; specifically, high levels of Nav1.3 immunoreactive proteins were located mainly in cytomegalic neurons of different sizes and shapes, not in balloon cells. Double-labeling studies showed most cytomegalic neurons expressing Nav1.3 colabeled with neuronal markers and glutamate receptors-1. Taken together, our results show an upregulation of Nav1.3 protein and a specific cellular distribution of Nav1.3 proteins in FCDIIb lesion tissue samples, suggesting that Nav1.3 may be involved in the generation of epileptic activity in FCDIIb.
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Abstract
Tuberous Sclerosis Complex (TSC) is an autosomal dominant multisystem disorder, characterized by the presence of hamartomatous lesions involving different organ systems, including the brain. Epilepsy is the most common presenting symptom, representing a major source of morbidity and mortality. Despite multiple antiepileptic drug combinations, in about two thirds of cases the patients present high-frequency drug-resistant epilepsy, and nonpharmacologic options may be considered. The aim of this work was to point out the current knowledge on epileptogenesis in TSC, the available medical therapies and diagnostic tools, and possible surgical strategies, with the intent to better understand the actual difficulties in controlling seizures and the results reported in the literature. There is also a section dedicated to the common association with cognitive impairment and the role of epilepsy control on its outcome.
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Affiliation(s)
- Federica Novegno
- Department of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
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36
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Epilepsy secondary to tuberous sclerosis: lessons learned and current challenges. Childs Nerv Syst 2010; 26:1495-504. [PMID: 20358377 DOI: 10.1007/s00381-010-1128-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 03/10/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND In tuberous sclerosis complex (TSC), a substantially increased risk of developing epilepsy is present as a result of a disruption of a TSC gene expression in the brain and secondary abnormal cellular differentiation, migration, and proliferation. Dysregulated excitation probably has its roots in the disruption of GABAergic interneuron development. There is an age-dependent electroclinical expression of seizures, and epilepsy is often quite severe and unremitting. DISCUSSION The majority of patients (>60%) who are candidates for surgery remain seizure-free after tuberectomy. During the recent years technical advances in the localization of the epileptogenic zone during the recent years have lead to a 63% of Engel class I status after surgery compared with a previous 52%. In medically refractory patients not suitable for surgery, vagus nerve stimulation has proved efficacy in significantly reducing seizure frequency in more than 50% of cases. New evidence suggests that mTOR inhibitors may be helpful in the management of intractable epilepsy for individuals with TSC.
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Boer K, Spliet W, van Rijen P, Jansen F, Aronica E. Expression patterns of AMOG in developing human cortex and malformations of cortical development. Epilepsy Res 2010; 91:84-93. [DOI: 10.1016/j.eplepsyres.2010.06.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/13/2010] [Accepted: 06/29/2010] [Indexed: 10/19/2022]
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Expression of the interleukin 6 system in cortical lesions from patients with tuberous sclerosis complex and focal cortical dysplasia type IIb. J Neuropathol Exp Neurol 2010; 69:838-49. [PMID: 20613633 DOI: 10.1097/nen.0b013e3181eaeae5] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Tuberous sclerosis complex (TSC) and focal cortical dysplasia type IIb (FCDIIb) are characterized by epilepsy-associated cerebral cortical malformations. To understand the potential role of the inflammatory cytokine interleukin 6 (IL-6) in the pathogenesis of these lesions, we analyzed the IL-6 system in TSC and FCDIIb cortical lesions and in control cortex (CTX). Greater messenger RNA and protein levels of IL-6 and of its receptors (i.e. IL-6 receptor [IL-6R] and glycoprotein 130 [gp130]) were observed in TSC and FCDIIb lesions versus CTX. Immunohistochemical analyses indicated that IL-6 and IL-6R were strongly expressed in misshapen cells, namely, dysmorphic neurons, giant neurons, and balloon cells. Glycoprotein 130 was diffusely expressed in nearly all cell types. Most IL-6/IL-6R+ misshapen cells colabeled with neuronal rather than astrocytic markers, suggesting a neuronal lineage; most IL-6/IL-6R+ balloon cells in FCDIIb expressed glial fibrillary acidic protein. Protein levels of Janus kinase 2 and phosphorylated signal transducer and activator of transcription 3 were greater than in CTX, suggesting involvement of the gp130-Janus kinase 2-signal transducer and activator of transcription 3 pathway in IL-6 signal transduction. Soluble IL-6R, but not soluble gp130, was greater in TSC and FCDIIb lesions than in CTX, indicating activation of this trans-signaling pathway. These results suggest that overexpression in the IL-6 system and activation of IL-6 signal transduction pathways may contribute to the pathogenesis of cortical lesions in TSC and FCDIIb.
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Vecht CJ, Wilms EB. Seizures in low- and high-grade gliomas: current management and future outlook. Expert Rev Anticancer Ther 2010; 10:663-669. [DOI: 10.1586/era.10.48] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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de Groot M, Toering ST, Boer K, Spliet WGM, Heimans JJ, Aronica E, Reijneveld JC. Expression of synaptic vesicle protein 2A in epilepsy-associated brain tumors and in the peritumoral cortex. Neuro Oncol 2010; 12:265-73. [PMID: 20167814 DOI: 10.1093/neuonc/nop028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Synaptic vesicle protein 2A (SV2A) has been identified as the binding site for the antiepileptic drug levetiracetam and is thought to decrease neuronal excitability. Since knockout of SV2A in mice leads to seizures, we hypothesized that a reduction in SV2A expression promotes seizure generation in epilepsy-associated brain tumors. We compared the SV2A expression and distribution in surgically removed tumor tissue (n = 63) and peritumoral cortex (n = 31) of patients with glial and glioneuronal tumors to normal control cortex obtained at autopsy in nonbrain tumor patients (n = 6). Additionally, we compared the SV2A expression and distribution in tumor patients with epilepsy (n = 39) with SV2A expression in tumor patients without epilepsy (n = 24). Immunohistochemistry in control cortex demonstrated strong and diffuse SV2A immunoreactivity (IR) throughout all cortical layers. Similar strong SV2A IR (with the same diffuse distribution pattern) was observed in the peritumoral cortical specimens in both patients with and without epilepsy. Modest SV2A IR was observed within the tumor area. The SV2A-positive cells detected within the tumor area were mainly entrapped neurons. Oligodendrogliomas and glioneuronal tumors displayed variable SV2A neuropil staining. In ganglioglioma (GG), strong SV2A IR was present along the dysplastic neuronal cell borders and processes. In both GG and dysembryoplastic neuroepithelial tumors, SV2A IR was occasionally observed within the neuronal perikarya. We found no differences in SV2A expression in the peritumoral cortex between the patients with and without epilepsy, which suggests that the role of SV2A in epileptogenesis in patients with glial tumors is questionable. The distinct pattern of SV2A IR in glioneuronal tumors suggests a redistribution of SV2A.
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Affiliation(s)
- Marjolein de Groot
- Department Of Neurology, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
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Down-regulation Synaptic Vesicle Protein 2A in the Anterior Temporal Neocortex of Patients with Intractable Epilepsy. J Mol Neurosci 2009; 39:354-9. [DOI: 10.1007/s12031-009-9288-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Accepted: 08/17/2009] [Indexed: 11/25/2022]
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