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Liu L, Ren D, Li K, Ji L, Feng M, Li Z, Meng L, He G, Shi Y. Unraveling schizophrenia's genetic complexity through advanced causal inference and chromatin 3D conformation. Schizophr Res 2024; 270:476-485. [PMID: 38996525 DOI: 10.1016/j.schres.2024.07.005] [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: 01/18/2024] [Revised: 07/01/2024] [Accepted: 07/03/2024] [Indexed: 07/14/2024]
Abstract
Schizophrenia is a polygenic complex disease with a heritability as high as 80 %, yet the mechanism of polygenic interaction in its pathogenesis remains unclear. Studying the interaction and regulation of schizophrenia susceptibility genes is crucial for unraveling the pathogenesis of schizophrenia and developing antipsychotic drugs. Therefore, we developed a bioinformatics method named GRACI (Gene Regulation Analysis based on Causal Inference) based on the principles of information theory, a causal inference model, and high order chromatin 3D conformation. GRACI captures the interaction and regulatory relationships between schizophrenia susceptibility genes by analyzing genotyping data. Two datasets, comprising 1459 and 2065 samples respectively, were analyzed, and the gene networks from both datasets were constructed. GRACI showcased superior accuracy when compared to widely adopted methods for detecting gene-gene interactions and intergenic regulation. This alignment was further substantiated by its correlation with chromatin high-order conformation patterns. Using GRACI, we identified three potential genes-KCNN3, KCNH1, and KCND3-that are directly associated with schizophrenia pathogenesis. Furthermore, the results of GRACI on the standalone dataset illustrated the method's applicability to other complex diseases. GRACI download: https://github.com/liuliangjie19/GRACI.
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Affiliation(s)
- Liangjie Liu
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Decheng Ren
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Keyi Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Lei Ji
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Mofan Feng
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Zhuoheng Li
- Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI 48109, USA
| | - Luming Meng
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510630, China
| | - Guang He
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Yi Shi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China; Research Institute for Doping Control, Shanghai University of Sport, Shanghai 200438, China.
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Di Matteo F, Mancuso F, Turcio R, Ciaglia T, Stagno C, Di Chio C, Campiglia P, Bertamino A, Giofrè SV, Ostacolo C, Iraci N. KCNT1 Channel Blockers: A Medicinal Chemistry Perspective. Molecules 2024; 29:2940. [PMID: 38931004 PMCID: PMC11206332 DOI: 10.3390/molecules29122940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/13/2024] [Accepted: 06/17/2024] [Indexed: 06/28/2024] Open
Abstract
Potassium channels have recently emerged as suitable target for the treatment of epileptic diseases. Among potassium channels, KCNT1 channels are the most widely characterized as responsible for several epileptic and developmental encephalopathies. Nevertheless, the medicinal chemistry of KCNT1 blockers is underdeveloped so far. In the present review, we describe and analyse the papers addressing the issue of KCNT1 blockers' development and identification, also evidencing the pros and the cons of the scientific approaches therein described. After a short introduction describing the epileptic diseases and the structure-function of potassium channels, we provide an extensive overview of the chemotypes described so far as KCNT1 blockers, and the scientific approaches used for their identification.
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Affiliation(s)
- Francesca Di Matteo
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Francesca Mancuso
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy
| | - Rita Turcio
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Tania Ciaglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Claudio Stagno
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy
| | - Carla Di Chio
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy
| | - Pietro Campiglia
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Alessia Bertamino
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Salvatore Vincenzo Giofrè
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy
| | - Carmine Ostacolo
- Department of Pharmacy, University of Salerno, Via G. Paolo II, 84084 Fisciano, Italy (R.T.); (T.C.)
| | - Nunzio Iraci
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (CHIBIOFARAM), University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy
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Lin ZJ, He JW, Zhu SY, Xue LH, Zheng JF, Zheng LQ, Huang BX, Chen GZ, Lin PX. Gene-gene interaction network analysis indicates CNTN2 is a candidate gene for idiopathic generalized epilepsy. Neurogenetics 2024; 25:131-139. [PMID: 38460076 DOI: 10.1007/s10048-024-00748-w] [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: 11/16/2023] [Accepted: 01/19/2024] [Indexed: 03/11/2024]
Abstract
Twin and family studies have established the genetic contribution to idiopathic generalized epilepsy (IGE). The genetic architecture of IGE is generally complex and heterogeneous, and the majority of the genetic burden in IGE remains unsolved. We hypothesize that gene-gene interactions contribute to the complex inheritance of IGE. CNTN2 (OMIM* 615,400) variants have been identified in cases with familial adult myoclonic epilepsy and other epilepsies. To explore the gene-gene interaction network in IGE, we took the CNTN2 gene as an example and investigated its co-occurrent genetic variants in IGE cases. We performed whole-exome sequencing in 114 unrelated IGE cases and 296 healthy controls. Variants were qualified with sequencing quality, minor allele frequency, in silico prediction, genetic phenotype, and recurrent case numbers. The STRING_TOP25 gene interaction network analysis was introduced with the bait gene CNTN2 (denoted as A). The gene-gene interaction pair mode was presumed to be A + c, A + d, A + e, with a leading gene A, or A + B + f, A + B + g, A + B + h, with a double-gene A + B, or other combinations. We compared the number of gene interaction pairs between the case and control groups. We identified three pairs in the case group, CNTN2 + PTPN18, CNTN2 + CNTN1 + ANK2 + ANK3 + SNTG2, and CNTN2 + PTPRZ1, while we did not discover any pairs in the control group. The number of gene interaction pairs in the case group was much more than in the control group (p = 0.021). Taking together the genetic bioinformatics, reported epilepsy cases, and statistical evidence in the study, we supposed CNTN2 as a candidate pathogenic gene for IGE. The gene interaction network analysis might help screen candidate genes for IGE or other complex genetic disorders.
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Affiliation(s)
- Zhi-Jian Lin
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Jun-Wei He
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Sheng-Yin Zhu
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Li-Hong Xue
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Jian-Feng Zheng
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Li-Qin Zheng
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Bi-Xia Huang
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Guo-Zhang Chen
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China
| | - Peng-Xing Lin
- Department of Neurology, School of Clinical Medicine, the Affiliated Hospital of Putian UniversityFujian Medical UniversityBrain Science Institute of Putian University, 999 Dongzhen East Road, Licheng District, Putian, 351100, China.
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4
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Costa B, Vale N. Virus-Induced Epilepsy vs. Epilepsy Patients Acquiring Viral Infection: Unravelling the Complex Relationship for Precision Treatment. Int J Mol Sci 2024; 25:3730. [PMID: 38612542 PMCID: PMC11011490 DOI: 10.3390/ijms25073730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/04/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
The intricate relationship between viruses and epilepsy involves a bidirectional interaction. Certain viruses can induce epilepsy by infecting the brain, leading to inflammation, damage, or abnormal electrical activity. Conversely, epilepsy patients may be more susceptible to viral infections due to factors, such as compromised immune systems, anticonvulsant drugs, or surgical interventions. Neuroinflammation, a common factor in both scenarios, exhibits onset, duration, intensity, and consequence variations. It can modulate epileptogenesis, increase seizure susceptibility, and impact anticonvulsant drug pharmacokinetics, immune system function, and brain physiology. Viral infections significantly impact the clinical management of epilepsy patients, necessitating a multidisciplinary approach encompassing diagnosis, prevention, and treatment of both conditions. We delved into the dual dynamics of viruses inducing epilepsy and epilepsy patients acquiring viruses, examining the unique features of each case. For virus-induced epilepsy, we specify virus types, elucidate mechanisms of epilepsy induction, emphasize neuroinflammation's impact, and analyze its effects on anticonvulsant drug pharmacokinetics. Conversely, in epilepsy patients acquiring viruses, we detail the acquired virus, its interaction with existing epilepsy, neuroinflammation effects, and changes in anticonvulsant drug pharmacokinetics. Understanding this interplay advances precision therapies for epilepsy during viral infections, providing mechanistic insights, identifying biomarkers and therapeutic targets, and supporting optimized dosing regimens. However, further studies are crucial to validate tools, discover new biomarkers and therapeutic targets, and evaluate targeted therapy safety and efficacy in diverse epilepsy and viral infection scenarios.
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Affiliation(s)
- Bárbara Costa
- PerMed Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal;
- CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
- Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal
| | - Nuno Vale
- PerMed Research Group, Center for Health Technology and Services Research (CINTESIS), Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal;
- CINTESIS@RISE, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
- Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Rua Doutor Plácido da Costa, s/n, 4200-450 Porto, Portugal
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Houdayer C, Phillips AM, Chabbert M, Bourreau J, Maroofian R, Houlden H, Richards K, Saadi NW, Dad'ová E, Van Bogaert P, Rupin M, Keren B, Charles P, Smol T, Riquet A, Pais L, O'Donnell-Luria A, VanNoy GE, Bayat A, Møller RS, Olofsson K, Abou Jamra R, Syrbe S, Dasouki M, Seaver LH, Sullivan JA, Shashi V, Alkuraya FS, Poss AF, Spence JE, Schnur RE, Forster IC, Mckenzie CE, Simons C, Wang M, Snell P, Kothur K, Buckley M, Roscioli T, Elserafy N, Dauriat B, Procaccio V, Henrion D, Lenaers G, Colin E, Verbeek NE, Van Gassen KL, Legendre C, Bonneau D, Reid CA, Howell KB, Ziegler A, Legros C. Mono and biallelic variants in HCN2 cause severe neurodevelopmental disorders. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.03.19.24303984. [PMID: 38562733 PMCID: PMC10984036 DOI: 10.1101/2024.03.19.24303984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Hyperpolarization activated Cyclic Nucleotide (HCN) gated channels are crucial for various neurophysiological functions, including learning and sensory functions, and their dysfunction are responsible for brain disorders, such as epilepsy. To date, HCN2 variants have only been associated with mild epilepsy and recently, one monoallelic missense variant has been linked to developmental and epileptic encephalopathy. Here, we expand the phenotypic spectrum of HCN2- related disorders by describing twenty-one additional individuals from fifteen unrelated families carrying HCN2 variants. Seventeen individuals had developmental delay/intellectual disability (DD/ID), two had borderline DD/ID, and one had borderline DD. Ten individuals had epilepsy with DD/ID, with median age of onset of 10 months, and one had epilepsy with normal development. Molecular diagnosis identified thirteen different pathogenic HCN2 variants, including eleven missense variants affecting highly conserved amino acids, one frameshift variant, and one in-frame deletion. Seven variants were monoallelic of which five occurred de novo, one was not maternally inherited, one was inherited from a father with mild learning disabilities, and one was of unknown inheritance. The remaining six variants were biallelic, with four homozygous and two compound heterozygous variants. Functional studies using two-electrode voltage-clamp recordings in Xenopus laevis oocytes were performed on three monoallelic variants, p.(Arg324His), p.(Ala363Val), and p.(Met374Leu), and three biallelic variants, p.(Leu377His), p.(Pro493Leu) and p.(Gly587Asp). The p.(Arg324His) variant induced a strong increase of HCN2 conductance, while p.(Ala363Val) and p.(Met374Leu) displayed dominant negative effects, leading to a partial loss of HCN2 channel function. By confocal imaging, we found that the p.(Leu377His), p.(Pro493Leu) and p.(Gly587Asp) pathogenic variants impaired membrane trafficking, resulting in a complete loss of HCN2 elicited currents in Xenopus oocytes. Structural 3D-analysis in depolarized and hyperpolarized states of HCN2 channels, revealed that the pathogenic variants p.(His205Gln), p.(Ser409Leu), p.(Arg324Cys), p.(Asn369Ser) and p.(Gly460Asp) modify molecular interactions altering HCN2 function. Taken together, our data broadens the clinical spectrum associated with HCN2 variants, and disclose that HCN2 is involved in developmental encephalopathy with or without epilepsy.
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Hu M, Liang C, Wang D. Implantable bioelectrodes: challenges, strategies, and future directions. Biomater Sci 2024; 12:270-287. [PMID: 38175154 DOI: 10.1039/d3bm01204b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Implantable bioelectrodes for regulating and monitoring biological behaviors have become indispensable medical devices in modern healthcare, alleviating pathological symptoms such as epilepsy and arrhythmia, and assisting in reversing conditions such as deafness and blindness. In recent years, developments in the fields of materials science and biomedical engineering have contributed to advances in research on implantable bioelectrodes. However, the foreign body reaction (FBR) is still a major constraint for the long-term application of electrodes. In this paper, four types of commonly used implantable bioelectrodes are reviewed, concentrating on their background, development, and a series of complications caused by FBR after long-term implantation. Strategies for resisting FBRs are then devised in terms of physics, chemistry, and nanotechnology. We analyze the major trends in the future development of implantable bioelectrodes and outline some promising research to optimize the long-term operational stability of electrodes. Although current implantable bioelectrodes have been able to achieve good biocompatibility, low impedance, and low mechanical mismatch and trauma, these devices still face the challenge of FBR. Resistance to FBR is still the key for the long-term effectiveness of bioelectrodes, and a better understanding of the mechanisms of FBR, as well as miniaturization, long-term passivation, and coupling with gene therapy may be the way forward for the next generation of implantable bioelectrodes.
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Affiliation(s)
- Mengyuan Hu
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Chunyong Liang
- School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Donghui Wang
- Hebei Key Laboratory of Biomaterials and Smart Theranostics, School of Health Sciences and Biomedical Engineering, Hebei University of Technology, Tianjin 300130, China.
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Bundalian L, Su YY, Chen S, Velluva A, Kirstein AS, Garten A, Biskup S, Battke F, Lal D, Heyne HO, Platzer K, Lin CC, Lemke JR, Le Duc D. Epilepsies of presumed genetic etiology show enrichment of rare variants that occur in the general population. Am J Hum Genet 2023; 110:1110-1122. [PMID: 37369202 PMCID: PMC10357498 DOI: 10.1016/j.ajhg.2023.06.004] [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: 03/13/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Previous studies suggested that severe epilepsies, e.g., developmental and epileptic encephalopathies (DEEs), are mainly caused by ultra-rare de novo genetic variants. For milder disease, rare genetic variants could contribute to the phenotype. To determine the importance of rare variants for different epilepsy types, we analyzed a whole-exome sequencing cohort of 9,170 epilepsy-affected individuals and 8,436 control individuals. Here, we separately analyzed three different groups of epilepsies: severe DEEs, genetic generalized epilepsy (GGE), and non-acquired focal epilepsy (NAFE). We required qualifying rare variants (QRVs) to occur in control individuals with an allele count ≥ 1 and a minor allele frequency ≤ 1:1,000, to be predicted as deleterious (CADD ≥ 20), and to have an odds ratio in individuals with epilepsy ≥ 2. We identified genes enriched with QRVs primarily in NAFE (n = 72), followed by GGE (n = 32) and DEE (n = 21). This suggests that rare variants may play a more important role for causality of NAFE than for DEE. Moreover, we found that genes harboring QRVs, e.g., HSGP2, FLNA, or TNC, encode proteins that are involved in structuring the brain extracellular matrix. The present study confirms an involvement of rare variants for NAFE that occur also in the general population, while in DEE and GGE, the contribution of such variants appears more limited.
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Affiliation(s)
- Linnaeus Bundalian
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany.
| | - Yin-Yuan Su
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Siwei Chen
- Analytic and Translational Genetics Unit, Department of Medicine, Boston, MA, USA; Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Akhil Velluva
- Division of General Biochemistry, Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, Leipzig University, 04103 Leipzig, Germany; Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Anna Sophia Kirstein
- Pediatric Research Center, University Hospital for Children and Adolescents, Leipzig University, 04103 Leipzig, Germany
| | - Antje Garten
- Pediatric Research Center, University Hospital for Children and Adolescents, Leipzig University, 04103 Leipzig, Germany
| | - Saskia Biskup
- CeGaT GmbH, 72076 Tuebingen, Germany; Hertie-Institute for Clinical Brain Research, 72070 Tubingen, Germany
| | | | - Dennis Lal
- Analytic and Translational Genetics Unit, Department of Medicine, Boston, MA, USA; Massachusetts General Hospital, Boston, MA 02114, USA; Cologne Center for Genomics, University of Cologne, 50937 Cologne, Germany
| | - Henrike O Heyne
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA; Hasso-Plattner-Institut for Digital Engineering, University of Potsdam, Potsdam, Germany; Hasso Plattner Institute at Mount Sinai, Mount Sinai School of Medicine, New York, NY, USA; Institute for Molecular Medicine Finland: FIMM, University of Helsinki, Helsinki, Finland
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Chen-Ching Lin
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany; Center for Rare Diseases, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Diana Le Duc
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany; Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany.
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Vien T, Ta M, Kimura L, Onay T, DeCaen P. Primary cilia TRP channel regulates hippocampal excitability. Proc Natl Acad Sci U S A 2023; 120:e2219686120. [PMID: 37216541 PMCID: PMC10235993 DOI: 10.1073/pnas.2219686120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 04/25/2023] [Indexed: 05/24/2023] Open
Abstract
Polycystins (PKD2, PKD2L1, and PKD2L2) are members of the transient receptor potential family, which form ciliary ion channels. Most notably, PKD2 dysregulation in the kidney nephron cilia is associated with polycystic kidney disease, but the function of PKD2L1 in neurons is undefined. In this report, we develop animal models to track the expression and subcellular localization of PKD2L1 in the brain. We discover that PKD2L1 localizes and functions as a Ca2+ channel in the primary cilia of hippocampal neurons that apically radiate from the soma. Loss of PKD2L1 expression ablates primary ciliary maturation and attenuates neuronal high-frequency excitability, which precipitates seizure susceptibility and autism spectrum disorder-like behavior in mice. The disproportionate impairment of interneuron excitability suggests that circuit disinhibition underlies the neurophenotypic features of these mice. Our results identify PKD2L1 channels as regulators of hippocampal excitability and the neuronal primary cilia as organelle mediators of brain electrical signaling.
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Affiliation(s)
- Thuy N. Vien
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - My C. Ta
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Louise F. Kimura
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Tuncer Onay
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL60911
| | - Paul G. DeCaen
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
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9
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Bundalian L, Su YY, Chen S, Velluva A, Kirstein AS, Garten A, Biskup S, Battke F, Lal D, Heyne HO, Platzer K, Lin CC, Lemke JR, Le Duc D. The role of rare genetic variants enrichment in epilepsies of presumed genetic etiology. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.01.17.23284702. [PMID: 36974069 PMCID: PMC10041669 DOI: 10.1101/2023.01.17.23284702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Previous studies suggested that severe epilepsies e.g., developmental and epileptic encephalopathies (DEE) are mainly caused by ultra-rare de novo genetic variants. For milder phenotypes, rare genetic variants could contribute to the phenotype. To determine the importance of rare variants for different epilepsy types, we analyzed a whole-exome sequencing cohort of 9,170 epilepsy-affected individuals and 8,436 controls. Here, we separately analyzed three different groups of epilepsies : severe DEEs, genetic generalized epilepsy (GGE), and non-acquired focal epilepsy (NAFE). We required qualifying rare variants (QRVs) to occur in controls at a minor allele frequency ≤ 1:1,000, to be predicted as deleterious (CADD≥20), and to have an odds ratio in epilepsy cases ≥2. We identified genes enriched with QRVs in DEE (n=21), NAFE (n=72), and GGE (n=32) - the number of enriched genes are found greatest in NAFE and least in DEE. This suggests that rare variants may play a more important role for causality of NAFE than in DEE. Moreover, we found that QRV-carrying genes e.g., HSGP2, FLNA or TNC are involved in structuring the brain extracellular matrix. The present study confirms an involvement of rare variants for NAFE, while in DEE and GGE, the contribution of such variants appears more limited.
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Affiliation(s)
- Linnaeus Bundalian
- Institute of Human Genetics, University of Leipzig Medical Center, 4103 Leipzig, Germany
| | - Yin-Yuan Su
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Siwei Chen
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Akhil Velluva
- Division of General Biochemistry, Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, Leipzig University, 04103, Leipzig, Germany
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
| | - Anna Sophia Kirstein
- Pediatric Research Center, University Hospital for Children and Adolescents, Leipzig University, 04103, Leipzig, Germany
| | - Antje Garten
- Pediatric Research Center, University Hospital for Children and Adolescents, Leipzig University, 04103, Leipzig, Germany
| | - Saskia Biskup
- CeGaT GmbH, 72076, Tuebingen, Germany
- Hertie-Institute for Clinical Brain Research, 72070, Tubingen, Germany
| | | | - Dennis Lal
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Cologne Center for Genomics, University of Cologne, 50937 Cologne, Germany
| | - Henrike O Heyne
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Hasso-Plattner-Institut for Digital Engineering, University of Potsdam, Potsdam, Germany
- Hasso Plattner Institute at Mount Sinai, Mount Sinai School of Medicine, NY, US
- Institute for Molecular Medicine Finland: FIMM, University of Helsinki, Helsinki, Finland
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, 4103 Leipzig, Germany
| | - Chen-Ching Lin
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, 4103 Leipzig, Germany
- Center for Rare Diseases, University of Leipzig Medical Center, 4103 Leipzig, Germany
| | - Diana Le Duc
- Institute of Human Genetics, University of Leipzig Medical Center, 4103 Leipzig, Germany
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
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10
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Zou S, Lan YL, Gong Y, Chen Z, Xu C. The role of ATP1A3 gene in epilepsy: We need to know more. Front Cell Neurosci 2023; 17:1143956. [PMID: 36866063 PMCID: PMC9972585 DOI: 10.3389/fncel.2023.1143956] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 01/23/2023] [Indexed: 02/16/2023] Open
Abstract
The ATP1A3 gene, which encodes the Na+/K+-ATPase α3 catalytic subunit, plays a crucial role in both physiological and pathological conditions in the brain, and mutations in this gene have been associated with a wide variety of neurological diseases by impacting the whole infant development stages. Cumulative clinical evidence suggests that some severe epileptic syndromes have been linked to mutations in ATP1A3, among which inactivating mutation of ATP1A3 has been intriguingly found to be a candidate pathogenesis for complex partial and generalized seizures, proposing ATP1A3 regulators as putative targets for the rational design of antiepileptic therapies. In this review, we introduced the physiological function of ATP1A3 and summarized the findings about ATP1A3 in epileptic conditions from both clinical and laboratory aspects at first. Then, some possible mechanisms of how ATP1A3 mutations result in epilepsy are provided. We think this review timely introduces the potential contribution of ATP1A3 mutations in both the genesis and progression of epilepsy. Taken that both the detailed mechanisms and therapeutic significance of ATP1A3 for epilepsy are not yet fully illustrated, we think that both in-depth mechanisms investigations and systematic intervention experiments targeting ATP1A3 are needed, and by doing so, perhaps a new light can be shed on treating ATP1A3-associated epilepsy.
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Affiliation(s)
- Shuang Zou
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yu-Long Lan
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China,*Correspondence: Yu-Long Lan ✉
| | - Yiwei Gong
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhong Chen
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
| | - Cenglin Xu
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, School of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China,Cenglin Xu ✉
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11
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Liu X, Sun Q, Cao Z, Liu W, Zhang H, Xue Z, Zhao J, Feng Y, Zhao F, Wang J, Wang X. Identification of RNA N6-methyladenosine regulation in epilepsy: Significance of the cell death mode, glycometabolism, and drug reactivity. Front Genet 2022; 13:1042543. [PMID: 36468034 PMCID: PMC9714553 DOI: 10.3389/fgene.2022.1042543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 11/07/2022] [Indexed: 07/28/2023] Open
Abstract
Epilepsy, a functional disease caused by abnormal discharge of neurons, has attracted the attention of neurologists due to its complex characteristics. N6-methyladenosine (m6A) is a reversible mRNA modification that plays essential role in various biological processes. Nevertheless, no previous study has systematically evaluated the role of m6A regulators in epilepsy. Here, using gene expression screening in the Gene Expression Omnibus GSE143272, we identified seven significant m6A regulator genes in epileptic and non-epileptic patients. The random forest (RF) model was applied to the screening, and seven m6A regulators (HNRNPC, WATP, RBM15, YTHDC1, YTHDC2, CBLL1, and RBMX) were selected as the candidate genes for predicting the risk of epilepsy. A nomogram model was then established based on the seven-candidate m6A regulators. Decision curve analysis preliminarily showed that patients with epilepsy could benefit from the nomogram model. The consensus clustering method was performed to divide patients with epilepsy into two m6A patterns (clusterA and clusterB) based on the selected significant m6A regulators. Principal component analysis algorithms were constructed to calculate the m6A score for each sample to quantify the m6A patterns. Patients in clusterB had higher m6A scores than those in clusterA. Furthermore, the patients in each cluster had unique immune cell components and different cell death patterns. Meanwhile, based on the M6A classification, a correlation between epilepsy and glucose metabolism was laterally verified. In conclusion, the m6A regulation pattern plays a vital role in the pathogenesis of epilepsy. The research on m6A regulatory factors will play a key role in guiding the immune-related treatment, drug selection, and identification of metabolism conditions and mechanisms of epilepsy in the future.
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Affiliation(s)
- Xuchen Liu
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qingyuan Sun
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Zexin Cao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Wenyu Liu
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Hengrui Zhang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Zhiwei Xue
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Jiangli Zhao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yifei Feng
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Feihu Zhao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Jiwei Wang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
| | - Xinyu Wang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, China
- Jinan Microecological Biomedicine Shandong Laboratory and Shandong Key Laboratory of Brain Function Remodeling, Jinan, China
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12
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Epigenetic genes and epilepsy - emerging mechanisms and clinical applications. Nat Rev Neurol 2022; 18:530-543. [PMID: 35859062 DOI: 10.1038/s41582-022-00693-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2022] [Indexed: 12/21/2022]
Abstract
An increasing number of epilepsies are being attributed to variants in genes with epigenetic functions. The products of these genes include factors that regulate the structure and function of chromatin and the placing, reading and removal of epigenetic marks, as well as other epigenetic processes. In this Review, we provide an overview of the various epigenetic processes, structuring our discussion around five function-based categories: DNA methylation, histone modifications, histone-DNA crosstalk, non-coding RNAs and chromatin remodelling. We provide background information on each category, describing the general mechanism by which each process leads to altered gene expression. We also highlight key clinical and mechanistic aspects, providing examples of genes that strongly associate with epilepsy within each class. We consider the practical applications of these findings, including tissue-based and biofluid-based diagnostics and precision medicine-based treatments. We conclude that variants in epigenetic genes are increasingly found to be causally involved in the epilepsies, with implications for disease mechanisms, treatments and diagnostics.
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13
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An Integrated Multi-Omic Network Analysis Identifies Seizure-Associated Dysregulated Pathways in the GAERS Model of Absence Epilepsy. Int J Mol Sci 2022; 23:ijms23116063. [PMID: 35682742 PMCID: PMC9181682 DOI: 10.3390/ijms23116063] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 11/17/2022] Open
Abstract
Absence epilepsy syndromes are part of the genetic generalized epilepsies, the pathogenesis of which remains poorly understood, although a polygenic architecture is presumed. Current focus on single molecule or gene identification to elucidate epileptogenic drivers is unable to fully capture the complex dysfunctional interactions occurring at a genetic/proteomic/metabolomic level. Here, we employ a multi-omic, network-based approach to characterize the molecular signature associated with absence epilepsy-like phenotype seen in a well validated rat model of genetic generalized epilepsy with absence seizures. Electroencephalographic and behavioral data was collected from Genetic Absence Epilepsy Rats from Strasbourg (GAERS, n = 6) and non-epileptic controls (NEC, n = 6), followed by proteomic and metabolomic profiling of the cortical and thalamic tissue of rats from both groups. The general framework of weighted correlation network analysis (WGCNA) was used to identify groups of highly correlated proteins and metabolites, which were then functionally annotated through joint pathway enrichment analysis. In both brain regions a large protein-metabolite module was found to be highly associated with the GAERS strain, absence seizures and associated anxiety and depressive-like phenotype. Quantitative pathway analysis indicated enrichment in oxidative pathways and a downregulation of the lysine degradation pathway in both brain regions. GSTM1 and ALDH2 were identified as central regulatory hubs of the seizure-associated module in the somatosensory cortex and thalamus, respectively. These enzymes are involved in lysine degradation and play important roles in maintaining oxidative balance. We conclude that the dysregulated pathways identified in the seizure-associated module may be involved in the aetiology and maintenance of absence seizure activity. This dysregulated activity could potentially be modulated by targeting one or both central regulatory hubs.
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14
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Ashrafuzzaman M. Artificial Intelligence, Machine Learning and Deep Learning in Ion Channel Bioinformatics. MEMBRANES 2021; 11:membranes11090672. [PMID: 34564489 PMCID: PMC8467682 DOI: 10.3390/membranes11090672] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 08/20/2021] [Accepted: 08/30/2021] [Indexed: 11/28/2022]
Abstract
Ion channels are linked to important cellular processes. For more than half a century, we have been learning various structural and functional aspects of ion channels using biological, physiological, biochemical, and biophysical principles and techniques. In recent days, bioinformaticians and biophysicists having the necessary expertise and interests in computer science techniques including versatile algorithms have started covering a multitude of physiological aspects including especially evolution, mutations, and genomics of functional channels and channel subunits. In these focused research areas, the use of artificial intelligence (AI), machine learning (ML), and deep learning (DL) algorithms and associated models have been found very popular. With the help of available articles and information, this review provide an introduction to this novel research trend. Ion channel understanding is usually made considering the structural and functional perspectives, gating mechanisms, transport properties, channel protein mutations, etc. Focused research on ion channels and related findings over many decades accumulated huge data which may be utilized in a specialized scientific manner to fast conclude pinpointed aspects of channels. AI, ML, and DL techniques and models may appear as helping tools. This review aims at explaining the ways we may use the bioinformatics techniques and thus draw a few lines across the avenue to let the ion channel features appear clearer.
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Affiliation(s)
- Md Ashrafuzzaman
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
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15
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Wei Z, Liu C, Wu Z, Cao M, Qiao X, Han T, Zhang Y, Liu Y, Deng Y. The prognosis of epilepsy patients with CACNA1H missense variants: A longitudinal cohort study. Seizure 2021; 91:52-59. [PMID: 34098317 DOI: 10.1016/j.seizure.2021.05.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE CACNA1H is regarded as a gene conferring susceptibility to generalised epilepsy. However, the prognosis of epilepsy patients carrying the CACNA1H missense variants of uncertain significance (VUS) is unknown. A prospective cohort was generated to determine the deleterious effects of these variants and to check whether the presence of these variants affects the prognosis of epilepsy patients. METHOD This study was conducted at Xijing Hospital in Xian, China. All patients were followed up for at least 1 year. Previous reports were searched for previously reported variants. Ensembl database was searched for variants in the general population. Combined Annotation Dependent Depletion (CADD) was used to evaluate the deleterious effect of variants. Logistic regression and Cox regression were used for data analysis. RESULTS The study included 176 epilepsy patients with or without CACNA1H variants. In epilepsy patients with missense variants, we found 35 different variants, including 33 variants with uncertain significance and 2 likely benign variants. No significant difference was observed between the distribution of CADD scores of the variants from this cohort, of the general population, and of those found in previous reports. Among epilepsy patients with missense variants, the number of antiepileptic drugs (AEDs) administered to the patients, a first-degree family history of epilepsy, and possibly the presence of abnormalities in brain radiology findings were correlated with the poorer prognosis. Among the entire cohort, the type of epilepsy, number of AEDs administered, and presence of abnormalities in brain radiology findings were associated with the prognosis of these patients. The deleterious effect of CACNA1H missense variants or their presence was not related to the prognosis of epilepsy patients. CONCLUSION The results of our study suggest that CACNA1H variants are related to multiple epilepsy syndromes. However, there is no strong evidence of the correlation between CACNA1H missense variants and a certain type of epilepsy. In our study cohort, both the deleterious effects and the presence of CACNA1H variants were found to be unrelated to the prognosis of patients with epilepsy. These findings suggest that CACNA1H missense variants that are classified as VUS might not influence the outcome of epilepsy.
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Affiliation(s)
- Zihan Wei
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Chao Liu
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Zhenyu Wu
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Centre, School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China
| | - Mi Cao
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Xiaozhi Qiao
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Tenghui Han
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Ying Zhang
- Department of Neurology, Xian International Medical Center, People's Republic of China
| | - Yonghong Liu
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Yanchun Deng
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China.
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16
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Yang X, Ding H, Wei H, Liu J, Liao P, Zhang Y, Wang X, Chi X. Association between GABRG2 rs211037 polymorphism and idiopathic generalized epilepsies: a meta-analysis. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-021-00043-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Abstract
Background
We performed this meta-analysis to investigate the association between GABRG2 rs211037polymorphism and the risk for idiopathic generalized epilepsies (IGEs).
Methods
Medline, Embase, Cochrane Library and Chinese National Knowledge Infrastructure (CNKI) databases were searched for eligible studies (until May 5, 2020) on the association between GABRG2 rs211037 polymorphism and IGE. The odds ratios were calculated using a fixed or random model in STATA 15.0 software. Subgroup analyses for ethnicity, age, source of controls, type of seizure syndrome and therapeutic responses were conducted.
Results
We found no significant associations between GABRG2 rs211037 polymorphism and the susceptibility to IGEs. In addition, no significant association was detected between GABRG2 rs211037 polymorphism and drug resistance in IGE patients. The results did not change after stratification by Asian population, healthy controls, children, juvenile myoclonic epilepsy, and childhood absence epilepsy.
Conclusion
The current studies indicated that the GABRG2 rs211037 polymorphism was not related to susceptibility or drug resistance of IGE. Further well-designed studies are needed to verify the results.
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17
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Lan Z, Zhang W, Xu J, Lu W. GABA A receptor-mediated inhibition of Dahlgren cells electrical activity in the olive flounder, Paralichthys olivaceus. Gen Comp Endocrinol 2021; 306:113753. [PMID: 33711316 DOI: 10.1016/j.ygcen.2021.113753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 02/10/2021] [Accepted: 02/28/2021] [Indexed: 11/24/2022]
Abstract
γ-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system. We investigated its potential role as a neurotransmitter in the neuroendocrine Dahlgren cell population of the caudal neurosecretory system (CNSS) of the flounder Paralichthys olivaceus. The application of GABA in vitro resulted in a decrease in electrical activity of Dahlgren cells, followed by an increase of the number of silent cells, together with a decreased firing frequency of all three activity patterns (tonic, phasic, bursting). GABAA receptor agonist etomidate decreased Dahlgren cell firing activity, in a similar way to GABA. The response to GABA was blocked by the GABAA receptor antagonist bicuculline. GABAA receptor gamma2 subunit (Gabrg2) and chloride channel (Clcn2) mRNA expression were significantly upregulated in the CNSS after GABA superfusion. These data suggest that GABA may modulate CNSS activity in vivo mediated by GABAA receptors.
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Affiliation(s)
- Zhaohui Lan
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China
| | - Wei Zhang
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China
| | - Jinling Xu
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China
| | - Weiqun Lu
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China.
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18
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Ademuwagun IA, Rotimi SO, Syrbe S, Ajamma YU, Adebiyi E. Voltage Gated Sodium Channel Genes in Epilepsy: Mutations, Functional Studies, and Treatment Dimensions. Front Neurol 2021; 12:600050. [PMID: 33841294 PMCID: PMC8024648 DOI: 10.3389/fneur.2021.600050] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 03/01/2021] [Indexed: 12/19/2022] Open
Abstract
Genetic epilepsy occurs as a result of mutations in either a single gene or an interplay of different genes. These mutations have been detected in ion channel and non-ion channel genes. A noteworthy class of ion channel genes are the voltage gated sodium channels (VGSCs) that play key roles in the depolarization phase of action potentials in neurons. Of huge significance are SCN1A, SCN1B, SCN2A, SCN3A, and SCN8A genes that are highly expressed in the brain. Genomic studies have revealed inherited and de novo mutations in sodium channels that are linked to different forms of epilepsies. Due to the high frequency of sodium channel mutations in epilepsy, this review discusses the pathogenic mutations in the sodium channel genes that lead to epilepsy. In addition, it explores the functional studies on some known mutations and the clinical significance of VGSC mutations in the medical management of epilepsy. The understanding of these channel mutations may serve as a strong guide in making effective treatment decisions in patient management.
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Affiliation(s)
- Ibitayo Abigail Ademuwagun
- Covenant University Bioinformatics Research, Covenant University, Ota, Nigeria
- Department of Biochemistry, Covenant University, Ota, Nigeria
| | - Solomon Oladapo Rotimi
- Covenant University Bioinformatics Research, Covenant University, Ota, Nigeria
- Department of Biochemistry, Covenant University, Ota, Nigeria
| | - Steffen Syrbe
- Clinic for Pediatric and Adolescent Medicine, Heidelberg University, Heidelberg, Germany
| | | | - Ezekiel Adebiyi
- Covenant University Bioinformatics Research, Covenant University, Ota, Nigeria
- Department of Computer and Information Sciences, Covenant University, Ota, Nigeria
- Division of Applied Bioinformatics, German Cancer Research Center (DKFZ), Heidelberg, Germany
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19
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Zhang X, Li Z, Liu Y, Gai Z. Great Expectations: Induced pluripotent stem cell technologies in neurodevelopmental impairments. Int J Med Sci 2021; 18:459-473. [PMID: 33390815 PMCID: PMC7757149 DOI: 10.7150/ijms.51842] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/09/2020] [Indexed: 12/15/2022] Open
Abstract
Somatic cells such as skin fibroblasts, umbilical cord blood, peripheral blood, urinary epithelial cells, etc., are transformed into induced pluripotent stem cells (iPSCs) by reprogramming technology, a milestone in the stem-cell research field. IPSCs are similar to embryonic stem cells (ESCs), exhibiting the potential to differentiate into various somatic cells. Still, the former avoid problems of immune rejection and medical ethics in the study of ESCs and clinical trials. Neurodevelopmental disorders are chronic developmental brain dysfunctions that affect cognition, exercise, social adaptability, behavior, etc. Due to various inherited or acquired causes, they seriously affect the physical and psychological health of infants and children. These include generalized stunting / mental disability (GDD/ID), Epilepsy, autism spectrum disease (ASD), and attention deficit hyperactivity disorder (ADHD). Most neurodevelopmental disorders are challenging to cure. Establishing a neurodevelopmental disorder system model is essential for researching and treating neurodevelopmental disorders. At this stage, the scarcity of samples is a bigger problem for studying neurological diseases based on the donor, ethics, etc. Some iPSCs are reprogrammed from somatic cells that carry disease-causing mutations. They differentiate into nerve cells by induction, which has the original characteristics of diseases. Disease-specific iPSCs are used to study the mechanism and pathogenesis of neurodevelopmental disorders. The process provided samples and the impetus for developing drugs and developing treatment plans for neurodevelopmental disorders. Here, this article mainly introduced the development of iPSCs, the currently established iPSCs disease models, and artificial organoids related to neurodevelopmental impairments. This technology will promote our understanding of neurodevelopmental impairments and bring great expectations to children with neurological disorders.
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Affiliation(s)
- Xue Zhang
- Pediatric Research Institute, Qilu Children's Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan 250022, China.,Jinan Pediatric Research Institute, Jinan Children's Hospital, Ji'nan 250022, China.,Neonatal Intensive Care Unit, Children's Medical Center, The Second Hospital of Shandong University, Ji'nan 250033, China
| | - Zilong Li
- Pediatric Research Institute, Qilu Children's Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan 250022, China.,Jinan Pediatric Research Institute, Jinan Children's Hospital, Ji'nan 250022, China
| | - Yi Liu
- Pediatric Research Institute, Qilu Children's Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan 250022, China.,Jinan Pediatric Research Institute, Jinan Children's Hospital, Ji'nan 250022, China
| | - Zhongtao Gai
- Pediatric Research Institute, Qilu Children's Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan 250022, China.,Jinan Pediatric Research Institute, Jinan Children's Hospital, Ji'nan 250022, China
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20
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Chow CY, Absalom N, Biggs K, King GF, Ma L. Venom-derived modulators of epilepsy-related ion channels. Biochem Pharmacol 2020; 181:114043. [PMID: 32445870 DOI: 10.1016/j.bcp.2020.114043] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 05/18/2020] [Indexed: 12/18/2022]
Abstract
Epilepsy is characterised by spontaneous recurrent seizures that are caused by an imbalance between neuronal excitability and inhibition. Since ion channels play fundamental roles in the generation and propagation of action potentials as well as neurotransmitter release at a subset of excitatory and inhibitory synapses, their dysfunction has been linked to a wide variety of epilepsies. Indeed, these unique proteins are the major biological targets for antiepileptic drugs. Selective targeting of a specific ion channel subtype remains challenging for small molecules, due to the high level of homology among members of the same channel family. As a consequence, there is a growing trend to target ion channels with biologics. Venoms are the best known natural source of ion channel modulators, and venom peptides are increasingly recognised as potential therapeutics due to their high selectivity and potency gained through millions of years of evolutionary selection pressure. Here we describe the major ion channel families involved in the pathogenesis of various types of epilepsy, including voltage-gated Na+, K+, Ca2+ channels, Cys-loop receptors, ionotropic glutamate receptors and P2X receptors, and currently available venom-derived peptides that target these channel proteins. Although only a small number of venom peptides have successfully progressed to the clinic, there is reason to be optimistic about their development as antiepileptic drugs, notwithstanding the challenges associated with development of any class of peptide drug.
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Affiliation(s)
- Chun Yuen Chow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Nathan Absalom
- Brain and Mind Centre, School of Pharmacy, Faculty of Health and Medicine, The University of Sydney, Sydney, NSW 2050, Australia
| | - Kimberley Biggs
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Glenn F King
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - Linlin Ma
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD 4111, Australia.
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21
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Zhao L, Luo F, Wang A, Zhang J, Wang Y, Zhao L, Wang Z, Pu Q. Quick stabilization of capillary for rapid determination of potassium ions in the blood of epilepsy patients by capillary electrophoresis without sample pretreatment. Electrophoresis 2020; 41:1273-1279. [PMID: 32358896 DOI: 10.1002/elps.202000022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 04/21/2020] [Accepted: 04/23/2020] [Indexed: 11/07/2022]
Abstract
Mutations in the potassium channel genes may be linked to the development of epilepsy and affect the blood potassium levels. Therefore, accurate determination of potassium in the blood will be critical to diagnose the cause of epilepsy. CE is a competent technique for the fast detection of multiple ions, but complicated matrices of a blood sample may cause significant variation of migration times and the peak shape. In this work, a procedure for rapid stabilization of the capillary inner surface through preflushing of a blood sample was employed. The process takes only 40 min for a capillary and then it can be used for more than 2 weeks. No pretreatment of the blood sample or other surface modification of the capillary is needed for the analysis. The RSDs of the migration time and peak area were reduced to 1.5 and 5.1% from 12.6 and 14.5%, respectively. The proposed method has been successfully applied to the determination of the potassium contents in the blood sample of patients with epilepsy at different stages. The recoveries of potassium ions in these blood samples are in a range from 86.5 to 104.5%.
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Affiliation(s)
- Litao Zhao
- School of Pharmacy, Lanzhou University, Lanzhou, P. R. China
| | - Fanghong Luo
- School of Pharmacy, Lanzhou University, Lanzhou, P. R. China
| | - Anting Wang
- School of Pharmacy, Lanzhou University, Lanzhou, P. R. China
| | - Jing Zhang
- School of Pharmacy, Lanzhou University, Lanzhou, P. R. China
| | - Yuanhang Wang
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, P. R. China
| | - Liangtao Zhao
- TSing Biomedical Research Center, The Second Hospital of Lanzhou University, Lanzhou, P. R. China
| | - Zhaoyan Wang
- School of Pharmacy, Lanzhou University, Lanzhou, P. R. China
| | - Qiaosheng Pu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, P. R. China
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22
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Lev B, Allen TW. Simulating ion channel activation mechanisms using swarms of trajectories. J Comput Chem 2020; 41:387-401. [PMID: 31743478 DOI: 10.1002/jcc.26102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 12/14/2022]
Abstract
Atomic-level studies of protein activity represent a significant challenge as a result of the complexity of conformational changes occurring on wide-ranging timescales, often greatly exceeding that of even the longest simulations. A prime example is the elucidation of protein allosteric mechanisms, where localized perturbations transmit throughout a large macromolecule to generate a response signal. For example, the conversion of chemical to electrical signals during synaptic neurotransmission in the brain is achieved by specialized membrane proteins called pentameric ligand-gated ion channels. Here, the binding of a neurotransmitter results in a global conformational change to open an ion-conducting pore across the nerve cell membrane. X-ray crystallography has produced static structures of the open and closed states of the proton-gated GLIC pentameric ligand-gated ion channel protein, allowing for atomistic simulations that can uncover changes related to activation. We discuss a range of enhanced sampling approaches that could be used to explore activation mechanisms. In particular, we describe recent application of an atomistic string method, based on Roux's "swarms of trajectories" approach, to elucidate the sequence and interdependence of conformational changes during activation. We illustrate how this can be combined with transition analysis and Brownian dynamics to extract thermodynamic and kinetic information, leading to understanding of what controls ion channel function. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Bogdan Lev
- School of Science, RMIT University, Melbourne, Victoria, 3000, Australia
| | - Toby W Allen
- School of Science, RMIT University, Melbourne, Victoria, 3000, Australia
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23
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van Loo KMJ, Becker AJ. Transcriptional Regulation of Channelopathies in Genetic and Acquired Epilepsies. Front Cell Neurosci 2020; 13:587. [PMID: 31992970 PMCID: PMC6971179 DOI: 10.3389/fncel.2019.00587] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/23/2019] [Indexed: 01/03/2023] Open
Abstract
Epilepsy is a common neurological disorder characterized by recurrent uncontrolled seizures and has an idiopathic “genetic” etiology or a symptomatic “acquired” component. Genetic studies have revealed that many epilepsy susceptibility genes encode ion channels, including voltage-gated sodium, potassium and calcium channels. The high prevalence of ion channels in epilepsy pathogenesis led to the causative concept of “ion channelopathies,” which can be elicited by specific mutations in the coding or promoter regions of genes in genetic epilepsies. Intriguingly, expression changes of the same ion channel genes by augmentation of specific transcription factors (TFs) early after an insult can underlie acquired epilepsies. In this study, we review how the transcriptional regulation of ion channels in both genetic and acquired epilepsies can be controlled, and compare these epilepsy “ion channelopathies” with other neurodevelopmental disorders.
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Affiliation(s)
- Karen M J van Loo
- Department of Neuropathology, Section for Translational Epilepsy Research, University of Bonn Medical Center, Bonn, Germany
| | - Albert J Becker
- Department of Neuropathology, Section for Translational Epilepsy Research, University of Bonn Medical Center, Bonn, Germany
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24
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Liu R, Wang J, Liang S, Zhang G, Yang X. Role of NKCC1 and KCC2 in Epilepsy: From Expression to Function. Front Neurol 2020; 10:1407. [PMID: 32010056 PMCID: PMC6978738 DOI: 10.3389/fneur.2019.01407] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 12/23/2019] [Indexed: 01/21/2023] Open
Abstract
As a main inhibitory neurotransmitter in the central nervous system, γ-aminobutyric acid (GABA) activates chloride-permeable GABAa receptors (GABAa Rs) and induces chloride ion (Cl−) flow, which relies on the intracellular chloride concentration ([Cl−]i) of the postsynaptic neuron. The Na-K-2Cl cotransporter isoform 1 (NKCC1) and the K-Cl cotransporter isoform 2 (KCC2) are two main cation-chloride cotransporters (CCCs) that have been implicated in human epilepsy. NKCC1 and KCC2 reset [Cl−]i by accumulating and extruding Cl−, respectively. Previous studies have shown that the profile of NKCC1 and KCC2 in neonatal neurons may reappear in mature neurons under some pathophysiological conditions, such as epilepsy. Although increasing studies focusing on the expression of NKCC1 and KCC2 have suggested that impaired chloride plasticity may be closely related to epilepsy, additional neuroelectrophysiological research aimed at studying the functions of NKCC1 and KCC2 are needed to understand the exact mechanism by which they induce epileptogenesis. In this review, we aim to briefly summarize the current researches surrounding the expression and function of NKCC1 and KCC2 in epileptogenesis and its implications on the treatment of epilepsy. We will also explore the potential for NKCC1 and KCC2 to be therapeutic targets for the development of novel antiepileptic drugs.
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Affiliation(s)
- Ru Liu
- Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Epilepsy, Center for Brain Disorders Research, Capital Medical University, Beijing, China.,Center of Epilepsy, Beijing Institute of Brain Disorders, Beijing, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Junling Wang
- Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Epilepsy, Center for Brain Disorders Research, Capital Medical University, Beijing, China.,Center of Epilepsy, Beijing Institute of Brain Disorders, Beijing, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Shuli Liang
- Department of Functional Neurosurgery, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Guojun Zhang
- Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Xiaofeng Yang
- Neuroelectrophysiological Laboratory, Xuanwu Hospital, Capital Medical University, Beijing, China.,Center of Epilepsy, Center for Brain Disorders Research, Capital Medical University, Beijing, China.,Center of Epilepsy, Beijing Institute of Brain Disorders, Beijing, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
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25
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Khalyfa A, Sanz-Rubio D. Genetics and Extracellular Vesicles of Pediatrics Sleep Disordered Breathing and Epilepsy. Int J Mol Sci 2019; 20:ijms20215483. [PMID: 31689970 PMCID: PMC6862182 DOI: 10.3390/ijms20215483] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/14/2019] [Accepted: 10/28/2019] [Indexed: 12/27/2022] Open
Abstract
Sleep remains one of the least understood phenomena in biology, and sleep disturbances are one of the most common behavioral problems in childhood. The etiology of sleep disorders is complex and involves both genetic and environmental factors. Epilepsy is the most popular childhood neurological condition and is characterized by an enduring predisposition to generate epileptic seizures, and the neurobiological, cognitive, psychological, and social consequences of this condition. Sleep and epilepsy are interrelated, and the importance of sleep in epilepsy is less known. The state of sleep also influences whether a seizure will occur at a given time, and this differs considerably for various epilepsy syndromes. The development of epilepsy has been associated with single or multiple gene variants. The genetics of epilepsy is complex and disorders exhibit significant genetic heterogeneity and variability in the expressivity of seizures. Phenobarbital (PhB) is the most widely used antiepileptic drug. With its principal mechanism of action to prolong the opening time of the γ-aminobutyric acid (GABA)-A receptor-associated chloride channel, it enhances chloride anion influx into neurons, with subsequent hyperpolarization, thereby reducing excitability. Enzymes that metabolize pharmaceuticals including PhB are well known for having genetic polymorphisms that contribute to adverse drug–drug interactions. PhB metabolism is highly dependent upon the cytochrome P450 (CYP450) and genetic polymorphisms can lead to variability in active drug levels. The highly polymorphic CYP2C19 isozymes are responsible for metabolizing a large portion of routinely prescribed drugs and variants contribute significantly to adverse drug reactions and therapeutic failures. A limited number of CYP2C19 single nucleotide polymorphisms (SNPs) are involved in drug metabolism. Extracellular vesicles (EVs) are circular membrane fragments released from the endosomal compartment as exosomes are shed from the surfaces of the membranes of most cell types. Increasing evidence indicated that EVs play a pivotal role in cell-to-cell communication. Theses EVs may play an important role between sleep, epilepsy, and treatments. The discovery of exosomes provides potential strategies for the diagnosis and treatment of many diseases including neurocognitive deficit. The aim of this study is to better understand and provide further knowledge about the metabolism and interactions between phenobarbital and CYP2C19 polymorphisms in children with epilepsy, interplay between sleep, and EVs. Understanding this interplay between epilepsy and sleep is helpful in the optimal treatment of all patients with epileptic seizures. The use of genetics and extracellular vesicles as precision medicine for the diagnosis and treatment of children with sleep disorder will improve the prognosis and the quality of life in patients with epilepsy.
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Affiliation(s)
- Abdelnaby Khalyfa
- Department of Pediatrics, Section of Sleep Medicine, The University of Chicago, Chicago, IL 60637, USA.
- Department of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA.
| | - David Sanz-Rubio
- Department of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA.
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26
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Gan J, Cai Q, Galer P, Ma D, Chen X, Huang J, Bao S, Luo R. Mapping the knowledge structure and trends of epilepsy genetics over the past decade: A co-word analysis based on medical subject headings terms. Medicine (Baltimore) 2019; 98:e16782. [PMID: 31393404 PMCID: PMC6709143 DOI: 10.1097/md.0000000000016782] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Over the past 10 years, epilepsy genetics has made dramatic progress. This study aimed to analyze the knowledge structure and the advancement of epilepsy genetics over the past decade based on co-word analysis of medical subject headings (MeSH) terms. METHODS Scientific publications focusing on epilepsy genetics from the PubMed database (January 2009-December 2018) were retrieved. Bibliometric information was analyzed quantitatively using Bibliographic Item Co-Occurrence Matrix Builder (BICOMB) software. A knowledge social network analysis and publication trend based on the high-frequency MeSH terms was built using VOSviewer. RESULTS According to the search strategy, a total of 5185 papers were included. Among all the extracted MeSH terms, 86 high-frequency MeSH terms were identified. Hot spots were clustered into 5 categories including: "ion channel diseases," "beyond ion channel diseases," "experimental research & epigenetics," "single nucleotide polymorphism & pharmacogenetics," and "genetic techniques". "Epilepsy," "mutation," and "seizures," were located at the center of the knowledge network. "Ion channel diseases" are typically in the most prominent position of epilepsy genetics research. "Beyond ion channel diseases" and "genetic techniques," however, have gradually grown into research cores and trends, such as "intellectual disability," "infantile spasms," "phenotype," "exome," " deoxyribonucleic acid (DNA) copy number variations," and "application of next-generation sequencing." While ion channel genes such as "SCN1A," "KCNQ2," "SCN2A," "SCN8A" accounted for nearly half of epilepsy genes in MeSH terms, a number of additional beyond ion channel genes like "CDKL5," "STXBP1," "PCDH19," "PRRT2," "LGI1," "ALDH7A1," "MECP2," "EPM2A," "ARX," "SLC2A1," and more were becoming increasingly popular. In contrast, gene therapies, treatment outcome, and genotype-phenotype correlations were still in their early stages of research. CONCLUSION This co-word analysis provides an overview of epilepsy genetics research over the past decade. The 5 research categories display publication hot spots and trends in epilepsy genetics research which could consequently supply some direction for geneticists and epileptologists when launching new projects.
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Affiliation(s)
- Jing Gan
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University) Ministry of Education, China
| | - Qianyun Cai
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University) Ministry of Education, China
| | - Peter Galer
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, PA
| | - Dan Ma
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
| | - Xiaolu Chen
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
| | - Jichong Huang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University) Ministry of Education, China
| | - Shan Bao
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University) Ministry of Education, China
| | - Rong Luo
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu
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27
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Flood E, Boiteux C, Lev B, Vorobyov I, Allen TW. Atomistic Simulations of Membrane Ion Channel Conduction, Gating, and Modulation. Chem Rev 2019; 119:7737-7832. [DOI: 10.1021/acs.chemrev.8b00630] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Emelie Flood
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Céline Boiteux
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Bogdan Lev
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Igor Vorobyov
- Department of Physiology & Membrane Biology/Department of Pharmacology, University of California, Davis, 95616, United States
| | - Toby W. Allen
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
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28
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Functional Nutrients for Epilepsy. Nutrients 2019; 11:nu11061309. [PMID: 31185666 PMCID: PMC6628163 DOI: 10.3390/nu11061309] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/05/2019] [Accepted: 06/06/2019] [Indexed: 12/11/2022] Open
Abstract
Epilepsy is a common neurological disorder of which seizures are a core symptom. Approximately one third of epileptic patients are resistant to antiepileptic drugs and therefore require alternative therapeutic options. Dietary and nutritional supplements can in some cases replace drugs, but with the exception of ketogenic diets, there are no officially recommended dietary considerations for patients with epilepsy. In this review we summarize a selection of nutritional suggestions that have proved beneficial in treating different types of epilepsy. We describe the types of seizures and epilepsy and follow this with an introduction to basic molecular mechanisms. We then examine several functional nutrients for which there is clinical evidence of therapeutic efficacy in reducing seizures or epilepsy-associated sudden death. We also discuss experimental results that demonstrate possible molecular mechanisms elicited by the administration of various nutrients. The availability of multiple dietary and nutritional candidates that show favorable outcomes in animals implies that assessing the clinical potential of these substances will improve translational medicine, ultimately benefitting epilepsy patients.
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29
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Thijs RD, Surges R, O'Brien TJ, Sander JW. Epilepsy in adults. Lancet 2019; 393:689-701. [PMID: 30686584 DOI: 10.1016/s0140-6736(18)32596-0] [Citation(s) in RCA: 902] [Impact Index Per Article: 180.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/08/2018] [Accepted: 10/11/2018] [Indexed: 12/11/2022]
Abstract
Epilepsy is one of the most common serious brain conditions, affecting over 70 million people worldwide. Its incidence has a bimodal distribution with the highest risk in infants and older age groups. Progress in genomic technology is exposing the complex genetic architecture of the common types of epilepsy, and is driving a paradigm shift. Epilepsy is a symptom complex with multiple risk factors and a strong genetic predisposition rather than a condition with a single expression and cause. These advances have resulted in the new classification of epileptic seizures and epilepsies. A detailed clinical history and a reliable eyewitness account of a seizure are the cornerstones of the diagnosis. Ancillary investigations can help to determine cause and prognosis. Advances in brain imaging are helping to identify the structural and functional causes and consequences of the epilepsies. Comorbidities are increasingly recognised as important aetiological and prognostic markers. Antiseizure medication might suppress seizures in up to two-thirds of all individuals but do not alter long-term prognosis. Epilepsy surgery is the most effective way to achieve long-term seizure freedom in selected individuals with drug-resistant focal epilepsy, but it is probably not used enough. With improved understanding of the gradual development of epilepsy, epigenetic determinants, and pharmacogenomics comes the hope for better, disease-modifying, or even curative, pharmacological and non-pharmacological treatment strategies. Other developments are clinical implementation of seizure detection devices and new neuromodulation techniques, including responsive neural stimulation.
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Affiliation(s)
- Roland D Thijs
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands; Department of Neurology, Leiden University Medical Centre, Leiden, Netherlands; NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London, UK
| | - Rainer Surges
- Section of Epileptology, Department of Neurology, University Hospital RWTH Aachen, Germany
| | - Terence J O'Brien
- Melbourne Brain Centre, Departments of Medicine and Neurology, Royal Melbourne Hospital, University of Melbourne, VIC, Australia; Departments of Neuroscience and Neurology, Central Clinical School, Monash University, The Alfred Hospital, Melbourne, VIC, Australia
| | - Josemir W Sander
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands; NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London, UK; Chalfont Centre for Epilepsy, Chalfont St Peter, UK.
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30
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Association of GABAA Receptor Gene with Epilepsy Syndromes. J Mol Neurosci 2018; 65:141-153. [PMID: 29785705 DOI: 10.1007/s12031-018-1081-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/01/2018] [Indexed: 12/19/2022]
Abstract
GABA has always been an inviting target in the etiology and treatment of epilepsy. The GABRA1, GABRG2, and GABRD genes provide instructions for making α1, ϒ2, and δ subunits of GABAA receptor protein respectively. GABAA is considered as one of the most important proteins and has found to play an important role in many neurological disorders. We explored the association of GABAA receptor gene mutation/SNPs in JME and LGS patients in Indian population. A total of 100 epilepsy syndrome patients (50 JME and 50 LGS) and 100 healthy control subjects were recruited and analyzed by AS-PCR and RFLP-PCR techniques. In our study, GABRA1 965 C > A mutation and 15 A > G polymorphism gene may play an important role in modulating the drug efficacy in LGS patients. The GABRA1 15 A > G polymorphism may also play an important role in the susceptibility of LGS and the inheritance of GG genotype of this polymorphism may provide an increased risk of development of LGS. The GABRG2 588 C > T polymorphism may decrease the duration of seizures in JME patients. The GABRD 659 G > A polymorphism may play an important role in the susceptibility of JME and LGS and this polymorphism may also increase the duration of postictal period in JME patients but may decrease the duration of seizure in LGS patients.
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31
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Shulskaya MV, Alieva AK, Vlasov IN, Zyrin VV, Fedotova EY, Abramycheva NY, Usenko TS, Yakimovsky AF, Emelyanov AK, Pchelina SN, Illarioshkin SN, Slominsky PA, Shadrina MI. Whole-Exome Sequencing in Searching for New Variants Associated With the Development of Parkinson's Disease. Front Aging Neurosci 2018; 10:136. [PMID: 29867446 PMCID: PMC5963122 DOI: 10.3389/fnagi.2018.00136] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/24/2018] [Indexed: 01/08/2023] Open
Abstract
Background: Parkinson’s disease (PD) is a complex disease with its monogenic forms accounting for less than 10% of all cases. Whole-exome sequencing (WES) technology has been used successfully to find mutations in large families. However, because of the late onset of the disease, only small families and unrelated patients are usually available. WES conducted in such cases yields in a large number of candidate variants. There are currently a number of imperfect software tools that allow the pathogenicity of variants to be evaluated. Objectives: We analyzed 48 unrelated patients with an alleged autosomal dominant familial form of PD using WES and developed a strategy for selecting potential pathogenetically significant variants using almost all available bioinformatics resources for the analysis of exonic areas. Methods: DNA sequencing of 48 patients with excluded frequent mutations was performed using an Illumina HiSeq 2500 platform. The possible pathogenetic significance of identified variants and their involvement in the pathogenesis of PD was assessed using SNP and Variation Suite (SVS), Combined Annotation Dependent Depletion (CADD) and Rare Exome Variant Ensemble Learner (REVEL) software. Functional evaluation was performed using the Pathway Studio database. Results: A significant reduction in the search range from 7082 to 25 variants in 23 genes associated with PD or neuronal function was achieved. Eight (FXN, MFN2, MYOC, NPC1, PSEN1, RET, SCN3A and SPG7) were the most significant. Conclusions: The multistep approach developed made it possible to conduct an effective search for potential pathogenetically significant variants, presumably involved in the pathogenesis of PD. The data obtained need to be further verified experimentally.
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Affiliation(s)
- Marina V Shulskaya
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Anelya Kh Alieva
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Ivan N Vlasov
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Vladimir V Zyrin
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Ekaterina Yu Fedotova
- Federal State Scientific Institution, Scientific Center of Neurology, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Natalia Yu Abramycheva
- Federal State Scientific Institution, Scientific Center of Neurology, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Tatiana S Usenko
- The Petersburg Nuclear Physics Institute of the National Research Center, Kurchatov Institute, Russian Academy of Sciences (RAS), Gatchina, Russia.,Federal State Budgetary Educational Institution of Higher Education, Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia
| | - Andrei F Yakimovsky
- Federal State Budgetary Educational Institution of Higher Education, Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia
| | - Anton K Emelyanov
- The Petersburg Nuclear Physics Institute of the National Research Center, Kurchatov Institute, Russian Academy of Sciences (RAS), Gatchina, Russia.,Federal State Budgetary Educational Institution of Higher Education, Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia
| | - Sofya N Pchelina
- The Petersburg Nuclear Physics Institute of the National Research Center, Kurchatov Institute, Russian Academy of Sciences (RAS), Gatchina, Russia.,Federal State Budgetary Educational Institution of Higher Education, Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia
| | - Sergei N Illarioshkin
- Federal State Scientific Institution, Scientific Center of Neurology, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Petr A Slominsky
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
| | - Maria I Shadrina
- Laboratory of Molecular Genetics of Hereditary Diseases, Institute of Molecular Genetics, Russian Academy of Sciences (RAS), Moscow, Russia
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32
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Oyrer J, Maljevic S, Scheffer IE, Berkovic SF, Petrou S, Reid CA. Ion Channels in Genetic Epilepsy: From Genes and Mechanisms to Disease-Targeted Therapies. Pharmacol Rev 2018; 70:142-173. [PMID: 29263209 DOI: 10.1124/pr.117.014456] [Citation(s) in RCA: 163] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 10/02/2017] [Indexed: 12/19/2022] Open
Abstract
Epilepsy is a common and serious neurologic disease with a strong genetic component. Genetic studies have identified an increasing collection of disease-causing genes. The impact of these genetic discoveries is wide reaching-from precise diagnosis and classification of syndromes to the discovery and validation of new drug targets and the development of disease-targeted therapeutic strategies. About 25% of genes identified in epilepsy encode ion channels. Much of our understanding of disease mechanisms comes from work focused on this class of protein. In this study, we review the genetic, molecular, and physiologic evidence supporting the pathogenic role of a number of different voltage- and ligand-activated ion channels in genetic epilepsy. We also review proposed disease mechanisms for each ion channel and highlight targeted therapeutic strategies.
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Affiliation(s)
- Julia Oyrer
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
| | - Snezana Maljevic
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
| | - Ingrid E Scheffer
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
| | - Samuel F Berkovic
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
| | - Christopher A Reid
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Melbourne, Australia (J.O., S.M., I.E.S., S.P., C.A.R.); Department of Medicine, Austin Health, University of Melbourne, Heidelberg West, Melbourne, Australia (I.E.S., S.F.B.); and Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia (I.E.S.)
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Ye H, Kaszuba S. Inhibitory or excitatory? Optogenetic interrogation of the functional roles of GABAergic interneurons in epileptogenesis. J Biomed Sci 2017; 24:93. [PMID: 29202749 PMCID: PMC5715558 DOI: 10.1186/s12929-017-0399-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 11/28/2017] [Indexed: 01/22/2023] Open
Abstract
Alteration in the excitatory/inhibitory neuronal balance is believed to be the underlying mechanism of epileptogenesis. Based on this theory, GABAergic interneurons are regarded as the primary inhibitory neurons, whose failure of action permits hyperactivity in the epileptic circuitry. As a consequence, optogenetic excitation of GABAergic interneurons is widely used for seizure suppression. However, recent evidence argues for the context-dependent, possibly “excitatory” roles that GABAergic cells play in epileptic circuitry. We reviewed current optogenetic approaches that target the “inhibitory” roles of GABAergic interneurons for seizure control. We also reviewed interesting evidence that supports the “excitatory” roles of GABAergic interneurons in epileptogenesis. GABAergic interneurons can provide excitatory effects to the epileptic circuits via several distinct neurological mechanisms. (1) GABAergic interneurons can excite postsynaptic neurons, due to the raised reversal potential of GABA receptors in the postsynaptic cells. (2) Continuous activity in GABAergic interneurons could lead to transient GABA depletion, which prevents their inhibitory effect on pyramidal cells. (3) GABAergic interneurons can synchronize network activity during seizure. (4) Some GABAergic interneurons inhibit other interneurons, causing disinhibition of pyramidal neurons and network hyperexcitability. The dynamic, context-dependent role that GABAergic interneurons play in seizure requires further investigation of their functions at single cell and circuitry level. New optogenetic protocols that target GABAergic inhibition should be explored for seizure suppression.
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Affiliation(s)
- Hui Ye
- Department of Biology, Loyola University Chicago, Quinlan Life Sciences Education and Research Center, 1032 W. Sheridan Rd, Chicago, IL, 60660, USA.
| | - Stephanie Kaszuba
- Department of Biology, Loyola University Chicago, Quinlan Life Sciences Education and Research Center, 1032 W. Sheridan Rd, Chicago, IL, 60660, USA
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Wu SZ, Ye H, Yang XG, Lu ZL, Qu Q, Qu J. Case-control pharmacogenetic study of HCN1/HCN2 variants and genetic generalized epilepsies. Clin Exp Pharmacol Physiol 2017; 45:226-233. [PMID: 29047147 DOI: 10.1111/1440-1681.12877] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/06/2017] [Accepted: 10/12/2017] [Indexed: 11/27/2022]
Abstract
Epilepsy is a common complex neurological disorder, and some forms are resistant to drug treatment. The HCN1/HCN2 genes encode hyperpolarization-activated cyclic nucleotide-gated channels, which play important roles in the electrophysiology of neurons. We investigated the association between HCN1/HCN2 variants and drug resistance or the risk of genetic generalized epilepsies (GGEs). We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to assess nine variants of HCN1/HCN2 in 284 healthy participants and 483 GGEs (279 drug-responsive, 204 drug-resistant). Frequencies of HCN2 rs7255568 and rs3752158 G alleles differed in GGEs and in controls (P = .039, P = .027, respectively). The frequency of HCN2 haplotype (CAC) was higher in patients than controls (P = .046). The frequency of the HCN1 rs10462087 CC+CT genotype was lower in patients with childhood absence epilepsy (CAE) than controls (P = .047). Rs7255568 was associated with the risk of CAE (P = .028) and juvenile myoclonic epilepsy (JME) (P = .02). Rs3752158 was associated with the risk of generalized tonic-clonic seizures, JME, and febrile seizures (all P < .05). The frequency of the HCN2 haplotype (CAC) was higher in patients with JME (P = .015) and in those with febrile seizures (P = .024) than in controls. No significant association was found between HCN1/HCN2 alleles, genotypes or haplotypes, and drug resistance in patients. After Bonferroni's multiple comparisons correction, only the HCN2 rs3752158 C allele and GC+CC genotype frequencies in patients with JME were higher than those in controls (19.2% vs 11.6%, odds ratio (OR) = 1.71, 95% CI = 1.18-2.32), P = .004 < 0.05/9; 36% vs 22.2%, OR = 1.62(1.18-2.23), P = .003 < 0.05/9). Our study suggests that HCN2 rs3752158 is involved in the susceptibility to JME.
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Affiliation(s)
- Shu-Zhi Wu
- Department of Neurology, The Third Clinical Institute Affiliated to Wenzhou Medical University & Wenzhou People's Hospital, Wenzhou, China
| | - Hua Ye
- Department of Neurology, The Third Clinical Institute Affiliated to Wenzhou Medical University & Wenzhou People's Hospital, Wenzhou, China
| | - Xiao-Guo Yang
- Department of Neurology, The Third Clinical Institute Affiliated to Wenzhou Medical University & Wenzhou People's Hospital, Wenzhou, China
| | - Zhi-Li Lu
- Department of Pathology, Hunan Cancer Hospital, Central South University, Changsha, China
| | - Qiang Qu
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China
| | - Jian Qu
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
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Masnada S, Hedrich UBS, Gardella E, Schubert J, Kaiwar C, Klee EW, Lanpher BC, Gavrilova RH, Synofzik M, Bast T, Gorman K, King MD, Allen NM, Conroy J, Ben Zeev B, Tzadok M, Korff C, Dubois F, Ramsey K, Narayanan V, Serratosa JM, Giraldez BG, Helbig I, Marsh E, O'Brien M, Bergqvist CA, Binelli A, Porter B, Zaeyen E, Horovitz DD, Wolff M, Marjanovic D, Caglayan HS, Arslan M, Pena SDJ, Sisodiya SM, Balestrini S, Syrbe S, Veggiotti P, Lemke JR, Møller RS, Lerche H, Rubboli G. Clinical spectrum and genotype-phenotype associations of KCNA2-related encephalopathies. Brain 2017; 140:2337-2354. [PMID: 29050392 DOI: 10.1093/brain/awx184] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 06/06/2017] [Indexed: 11/14/2022] Open
Abstract
Recently, de novo mutations in the gene KCNA2, causing either a dominant-negative loss-of-function or a gain-of-function of the voltage-gated K+ channel Kv1.2, were described to cause a new molecular entity within the epileptic encephalopathies. Here, we report a cohort of 23 patients (eight previously described) with epileptic encephalopathy carrying either novel or known KCNA2 mutations, with the aim to detail the clinical phenotype associated with each of them, to characterize the functional effects of the newly identified mutations, and to assess genotype-phenotype associations. We identified five novel and confirmed six known mutations, three of which recurred in three, five and seven patients, respectively. Ten mutations were missense and one was a truncation mutation; de novo occurrence could be shown in 20 patients. Functional studies using a Xenopus oocyte two-microelectrode voltage clamp system revealed mutations with only loss-of-function effects (mostly dominant-negative current amplitude reduction) in eight patients or only gain-of-function effects (hyperpolarizing shift of voltage-dependent activation, increased amplitude) in nine patients. In six patients, the gain-of-function was diminished by an additional loss-of-function (gain-and loss-of-function) due to a hyperpolarizing shift of voltage-dependent activation combined with either decreased amplitudes or an additional hyperpolarizing shift of the inactivation curve. These electrophysiological findings correlated with distinct phenotypic features. The main differences were (i) predominant focal (loss-of-function) versus generalized (gain-of-function) seizures and corresponding epileptic discharges with prominent sleep activation in most cases with loss-of-function mutations; (ii) more severe epilepsy, developmental problems and ataxia, and atrophy of the cerebellum or even the whole brain in about half of the patients with gain-of-function mutations; and (iii) most severe early-onset phenotypes, occasionally with neonatal onset epilepsy and developmental impairment, as well as generalized and focal seizures and EEG abnormalities for patients with gain- and loss-of-function mutations. Our study thus indicates well represented genotype-phenotype associations between three subgroups of patients with KCNA2 encephalopathy according to the electrophysiological features of the mutations.
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Affiliation(s)
- Silvia Masnada
- Brain and Behaviour Department, University of Pavia, Italy.,Department of Child Neurology and Psychiatry, IRCCS C. Mondino National Neurological Institute, Pavia, Italy.,Danish Epilepsy Centre, Dianalund, Denmark
| | - Ulrike B S Hedrich
- Department of Neurology and Epileptology, Hertie Institute of Clinical Brain Research, University of Tübingen, Germany
| | - Elena Gardella
- Clinical Neurophysiology, Danish Epilepsy Centre, Dianalund, Denmark.,Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Julian Schubert
- Department of Neurology and Epileptology, Hertie Institute of Clinical Brain Research, University of Tübingen, Germany
| | - Charu Kaiwar
- Center for Individualized Medicine, Mayo Clinic, Scottsdale AZ, USA
| | - Eric W Klee
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | | | - Ralitza H Gavrilova
- Departments of Clinical Genomics and Neurology Mayo Clinic, Rochester, MN, USA
| | - Matthis Synofzik
- Department of Neurodegeneration, Hertie Institute for Clinical Brain Research (HIH), University of Tübingen, Tübingen, Germany.,German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | | | - Kathleen Gorman
- Department of Neurology and Clinical Neurophysiology, Children's University Hospital, Temple Street, Dublin, Ireland.,Academic Centre on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland
| | - Mary D King
- Department of Neurology and Clinical Neurophysiology, Children's University Hospital, Temple Street, Dublin, Ireland.,Academic Centre on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland
| | - Nicholas M Allen
- Department of Neurology and Clinical Neurophysiology, Children's University Hospital, Temple Street, Dublin, Ireland.,Academic Centre on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland
| | - Judith Conroy
- Academic Centre on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland
| | - Bruria Ben Zeev
- Sackler school of medicine Tel Aviv University, Tel Aviv, Israel
| | - Michal Tzadok
- Pediatric Neurology Unit, Sheba Medical Center, Israel
| | - Christian Korff
- Pediatric Neurology University Hospitals, Geneva, Switzerland
| | | | - Keri Ramsey
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ, USA.,Neurogenomics Division, Translational Genomics Research Institute, Phoenix, AZ, USA
| | - Vinodh Narayanan
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ, USA.,Neurogenomics Division, Translational Genomics Research Institute, Phoenix, AZ, USA
| | - Jose M Serratosa
- Neurology Laboratory and Epilepsy Unit, Department of Neurology, IIS- Fundación Jiménez Díaz, UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Beatriz G Giraldez
- Neurology Laboratory and Epilepsy Unit, Department of Neurology, IIS- Fundación Jiménez Díaz, UAM, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Ingo Helbig
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, USA.,Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel Germany
| | - Eric Marsh
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Margaret O'Brien
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, USA
| | | | - Adrian Binelli
- Department of Pediatric Neurology, Elizalde Children's Hospital, Buenos Aires, Argentina.,Sociedad Argentina de Neurología Infantil (SANI) / Argentinian Child Neurology Society
| | - Brenda Porter
- Department of Neurology and Neurological Sciences, Stanford University, Palo Alto California, USA
| | - Eduardo Zaeyen
- Neuropediatrics Committee of State of Rio De Janeiro, Rio De Janeiro, Brazil
| | - Dafne D Horovitz
- Medical Genetics Department, National Institute for Women, Children and Adolescents Health Fernandes Figueira - Fiocruz, Rio de Janeiro, Brazil
| | - Markus Wolff
- Department of Pediatric Neurology and Developmental Medecine, University Children's Hospital, Tübingen, Germany
| | | | - Hande S Caglayan
- Department of Molecular Biology and Genetics, Bogazici University, Istanbul, Turkey
| | - Mutluay Arslan
- Department of Pediatric Neurology, Gulhane Military Medical School, Ankara, Turkey
| | - Sergio D J Pena
- GENE - Núcleo de Genética Médica, Belo Horizonte, MG, Brazil
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology and Epilepsy Society, UK
| | - Simona Balestrini
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology and Epilepsy Society, UK
| | - Steffen Syrbe
- Department of General Paediatrics, Division of Child Neurology and Inherited Metabolic Diseases, Centre for Paediatrics and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany.,Department of Women and Child Health, Hospital for Children and Adolescents, University of Leipzig Hospitals and Clinics, Leipzig, Germany
| | - Pierangelo Veggiotti
- Brain and Behaviour Department, University of Pavia, Italy.,Department of Child Neurology and Psychiatry, IRCCS C. Mondino National Neurological Institute, Pavia, Italy
| | | | - Rikke S Møller
- Danish Epilepsy Centre, Dianalund, Denmark.,Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute of Clinical Brain Research, University of Tübingen, Germany
| | - Guido Rubboli
- Danish Epilepsy Centre, Dianalund, Denmark.,University of Copenhagen, Copenhagen, Denmark
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Maljevic S, Reid CA, Petrou S. Models for discovery of targeted therapy in genetic epileptic encephalopathies. J Neurochem 2017; 143:30-48. [PMID: 28742937 DOI: 10.1111/jnc.14134] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 12/20/2022]
Abstract
Epileptic encephalopathies are severe disorders emerging in the first days to years of life that commonly include refractory seizures, various types of movement disorders, and different levels of developmental delay. In recent years, many de novo occurring variants have been identified in individuals with these devastating disorders. To unravel disease mechanisms, the functional impact of detected variants associated with epileptic encephalopathies is investigated in a range of cellular and animal models. This review addresses efforts to advance and use such models to identify specific molecular and cellular targets for the development of novel therapies. We focus on ion channels as the best-studied group of epilepsy genes. Given the clinical and genetic heterogeneity of epileptic encephalopathy disorders, experimental models that can reflect this complexity are critical for the development of disease mechanisms-based targeted therapy. The convergence of technological advances in gene sequencing, stem cell biology, genome editing, and high throughput functional screening together with massive unmet clinical needs provides unprecedented opportunities and imperatives for precision medicine in epileptic encephalopathies.
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Affiliation(s)
- Snezana Maljevic
- The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
| | - Christopher A Reid
- The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, Melbourne, Australia.,University of Melbourne, Melbourne, Australia
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37
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Lev B, Murail S, Poitevin F, Cromer BA, Baaden M, Delarue M, Allen TW. String method solution of the gating pathways for a pentameric ligand-gated ion channel. Proc Natl Acad Sci U S A 2017; 114:E4158-E4167. [PMID: 28487483 PMCID: PMC5448215 DOI: 10.1073/pnas.1617567114] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Pentameric ligand-gated ion channels control synaptic neurotransmission by converting chemical signals into electrical signals. Agonist binding leads to rapid signal transduction via an allosteric mechanism, where global protein conformational changes open a pore across the nerve cell membrane. We use all-atom molecular dynamics with a swarm-based string method to solve for the minimum free-energy gating pathways of the proton-activated bacterial GLIC channel. We describe stable wetted/open and dewetted/closed states, and uncover conformational changes in the agonist-binding extracellular domain, ion-conducting transmembrane domain, and gating interface that control communication between these domains. Transition analysis is used to compute free-energy surfaces that suggest allosteric pathways; stabilization with pH; and intermediates, including states that facilitate channel closing in the presence of an agonist. We describe a switching mechanism that senses proton binding by marked reorganization of subunit interface, altering the packing of β-sheets to induce changes that lead to asynchronous pore-lining M2 helix movements. These results provide molecular details of GLIC gating and insight into the allosteric mechanisms for the superfamily of pentameric ligand-gated channels.
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Affiliation(s)
- Bogdan Lev
- School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - Samuel Murail
- Laboratoire de Biochimie Théorique, CNRS, UPR9080, Université Paris Diderot, Sorbonne Paris Cité, F-75005 Paris, France
| | - Frédéric Poitevin
- Department of Structural Biology, Stanford University, Stanford, CA 94305
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA 94025
| | - Brett A Cromer
- School of Science, RMIT University, Melbourne, VIC 3001, Australia
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia
| | - Marc Baaden
- Laboratoire de Biochimie Théorique, CNRS, UPR9080, Université Paris Diderot, Sorbonne Paris Cité, F-75005 Paris, France
| | - Marc Delarue
- Department of Structural Biology and Chemistry, Institut Pasteur and UMR 3528 du CNRS, F-75015 Paris, France
| | - Toby W Allen
- School of Science, RMIT University, Melbourne, VIC 3001, Australia;
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Tomlinson SE, Howells J, Burke D. In vivo assessment of neurological channelopathies: Application of peripheral nerve excitability studies. Neuropharmacology 2017; 132:98-107. [PMID: 28476643 DOI: 10.1016/j.neuropharm.2017.04.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 04/19/2017] [Accepted: 04/29/2017] [Indexed: 12/14/2022]
Abstract
With the rapid evolution of understanding of neurological channelopathies comes a need for sensitive tools to evaluate patients in clinical practice. Neurological channelopathies with a single-gene basis can manifest as seizures, headache, ataxia, vertigo, confusion, weakness and neuropathic pain and it is likely that other genetic factors contribute to the phenotype of many of these disorders. Ion channel dysfunction can result in abnormal cell membrane excitability but utilisation of advanced neurophysiology techniques has lagged behind developments in clinical, genetic and imaging evaluation of channelopathies. However, momentum in the application of in vivo axonal excitability testing sees these tests emerging as valuable tools, with the capacity to provide sensitive and specific insights into the mechanism of disease. While single-channel function cannot be directly measured in vivo, evaluation of subjects with single-gene channelopathies has provided insights into the effects of mutation-related alterations of membrane excitability, as well as compensatory adaptive changes. By showing how ion channel dysfunction can affect axonal excitability in vivo, studies of the excitability of peripheral nerve axons complement in vitro analysis of single channel activity. The interpretation of results is enhanced by mathematical modelling of axonal function and insights provided by in vitro work. This article is part of the Special Issue entitled 'Channelopathies.'
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Affiliation(s)
- Susan E Tomlinson
- Sydney Medical School, University of Sydney, Sydney, Australia; Department of Neurology, St Vincent's Hospital, Sydney, Australia.
| | - James Howells
- Brain and Mind Centre, University of Sydney, Sydney, Australia
| | - David Burke
- Sydney Medical School, University of Sydney, Sydney, Australia; Department of Neurology, Royal Prince Alfred Hospital, Sydney, Australia
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Zhang D, Liu X, Deng X. Genetic basis of pediatric epilepsy syndromes. Exp Ther Med 2017; 13:2129-2133. [PMID: 28565819 PMCID: PMC5443213 DOI: 10.3892/etm.2017.4267] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 03/21/2017] [Indexed: 01/26/2023] Open
Abstract
Childhood epilepsy affects ~0.5-1% in the general population worldwide. Early-onset epileptic encephalopathies are considered to be severe neurological disorders, which lead to impaired motor, cognitive, and sensory development due to recurrence of seizures. Many of the observed epilepsy phenotypes are associated with specific chromosomal imbalances and thus display gene dosage effects, and also specific mutations of a variety of genes ranging from ion channels to transcription factors. High throughput sequencing technologies and whole exome sequencing have led to the recognition of several new candidate genes with a possible role in the pathogenesis of epileptic encephalopathies. The mutations causing channelopathies can be either a gain or a loss of ion channel function and contribute to the pathogenesis of epilepsy syndrome. Nearly 300 mutations of SCN1A gene coding for the Nav1.1 channel protein have been identified that contribute to the pathology of epilepsy. Besides Na, potassium and calcium channels are also implicated in epileptic encephalopathies. Therapeutic management of epileptic encephalopathies has been challenging as the majority of the medications are not efficient and often have many undesirable side effects. A better understanding of the molecular nature of epilepsy in an individual is important to design a personalized medication, considering the number of possible genetic mutations that can contribute to epileptic encephalopathies.
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Affiliation(s)
- Dongli Zhang
- Department of Neurology, Xuzhou Children's Hospital, Xuzhou, Jiangsu 221002, P.R. China
| | - Xiaoming Liu
- Department of Neurology, Xuzhou Children's Hospital, Xuzhou, Jiangsu 221002, P.R. China
| | - Xingqiang Deng
- Department of Neurology, Xuzhou Children's Hospital, Xuzhou, Jiangsu 221002, P.R. China
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40
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Fukata Y, Yokoi N, Miyazaki Y, Fukata M. The LGI1–ADAM22 protein complex in synaptic transmission and synaptic disorders. Neurosci Res 2017; 116:39-45. [DOI: 10.1016/j.neures.2016.09.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 09/18/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022]
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Abstract
Accumulating evidence suggest that TRPC channels play critical roles in various aspects of epileptogenesis. TRPC1/4 channels are major contributors to nonsynaptically derived epileptiform burst firing in the CA1 and the lateral septum. TRPC7 channels play a critical role in synaptically derived epileptiform burst firing. The reduction of spontaneous epileptiform bursting in the CA3 is correlated to a reduction in pilocarpine-induced SE in vivo in TRPC7 knockout mice. TRPC channels are also significant contributors to SE-induced neuronal cell death. Although the pilocarpine-induced SE itself is not significantly reduced, the SE-induced neuronal cell death is significantly reduced in the CA1 and the lateral septum, indicating that TRPC1/4 channels directly contribute to SE-induced neuronal cell death. Genetic ablation of TRPC5 also reduces SE-induced neuronal cell death in the CA1 and CA3 areas of the hippocampus.
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42
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GABA Australis, some reflections on the history of GABA receptor research in Australia. Pharmacol Res 2016; 116:32-38. [PMID: 28017666 DOI: 10.1016/j.phrs.2016.12.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 12/10/2016] [Accepted: 12/21/2016] [Indexed: 12/12/2022]
Abstract
Research on GABA receptors has a long history in Australia dating from 1958 with David Curtis and his colleagues in Canberra. This review traces many of the advances made in Australia guided by highly cited publications and some obscure ones. It covers the discovery of key chemicals with which to investigate GABA receptor function including bicuculline, muscimol, phaclofen, THIP and (+)-CAMP. Also described are findings relevant to the involvement of mutant GABA receptors in inherited epilepsy. The modulation of GABA receptors by a bewildering range of chemicals, especially by flavonoids and terpenoids, is discussed.
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43
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In Silico Prediction of Gamma-Aminobutyric Acid Type-A Receptors Using Novel Machine-Learning-Based SVM and GBDT Approaches. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2375268. [PMID: 27579307 PMCID: PMC4992803 DOI: 10.1155/2016/2375268] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 06/08/2016] [Accepted: 06/19/2016] [Indexed: 11/17/2022]
Abstract
Gamma-aminobutyric acid type-A receptors (GABAARs) belong to multisubunit membrane spanning ligand-gated ion channels (LGICs) which act as the principal mediators of rapid inhibitory synaptic transmission in the human brain. Therefore, the category prediction of GABAARs just from the protein amino acid sequence would be very helpful for the recognition and research of novel receptors. Based on the proteins' physicochemical properties, amino acids composition and position, a GABAAR classifier was first constructed using a 188-dimensional (188D) algorithm at 90% cd-hit identity and compared with pseudo-amino acid composition (PseAAC) and ProtrWeb web-based algorithms for human GABAAR proteins. Then, four classifiers including gradient boosting decision tree (GBDT), random forest (RF), a library for support vector machine (libSVM), and k-nearest neighbor (k-NN) were compared on the dataset at cd-hit 40% low identity. This work obtained the highest correctly classified rate at 96.8% and the highest specificity at 99.29%. But the values of sensitivity, accuracy, and Matthew's correlation coefficient were a little lower than those of PseAAC and ProtrWeb; GBDT and libSVM can make a little better performance than RF and k-NN at the second dataset. In conclusion, a GABAAR classifier was successfully constructed using only the protein sequence information.
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Dos Passos GR, Fernández AC, Vasques AM, Martins WA, Palmini A. Mother and daughter with adolescent-onset severe frontal lobe dysfunction and epilepsy. Dement Neuropsychol 2016; 10:238-243. [PMID: 29213461 PMCID: PMC5642421 DOI: 10.1590/s1980-5764-2016dn1003011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Familial cases of early-onset prominent frontal lobe dysfunction associated with
epilepsy have not been reported to date. We report a mother and her only daughter
with incapacitating behavioral manifestations of frontal lobe dysfunction and
epilepsy of variable severity. The possibility of a hitherto undescribed genetic
condition is discussed.
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Affiliation(s)
| | - Alonso Cuadrado Fernández
- Neurology Service, São Lucas Hospital, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre RS, Brazil
| | - Adriana Machado Vasques
- Institute of Geriatrics and Gerontology, Pontifical Catholic University of Rio Grande do Sul, RS, Porto Alegre, Brazil
| | - William Alves Martins
- Neurology Service, São Lucas Hospital, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre RS, Brazil.,Institute of Geriatrics and Gerontology, Pontifical Catholic University of Rio Grande do Sul, RS, Porto Alegre, Brazil
| | - André Palmini
- Neurology Service, São Lucas Hospital, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre RS, Brazil.,Porto Alegre Epilepsy Surgery Program, Neurology Service, São Lucas Hospital, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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45
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Dixit AB, Banerjee J, Ansari A, Tripathi M, Chandra SP. Mutations in GABRG2 receptor gene are not a major factor in the pathogenesis of mesial temporal lobe epilepsy in Indian population. Ann Indian Acad Neurol 2016; 19:236-41. [PMID: 27293336 PMCID: PMC4888688 DOI: 10.4103/0972-2327.182304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AIM This study is focused on GABRG2 gene sequence variations in patients with mesial temporal lobe epilepsy (mTLE). The GABAAreceptor is a heteropentameric receptor and alpha-1 beta-2 gamma-2 subunits combination is most abundant and present in almost all regions of the brain. The gamma-2 subunit (GABRG2) gene mutations have been reported in different epilepsy pathologies. In the present study we have looked for GABRG2 gene sequence variations in patients with mTLE. MATERIALS AND METHODS Twenty patients (12 females and eight males, age 4.6-38 years) with MTLE were recruited for this investigation. Patients were recommended for epilepsy surgery after all clinical investigations as per the epilepsy protocol. Ethnically matched glioma or meningioma patients were considered as nonepileptic controls. During temporal lobectomy of amygdalohippocampectomy, hippocampal brain tissue samples were resected guided by intraoperative electrocorticography (ECoG) activity. All 11 exons of GABRG2 gene with their flanking intronic regions were amplified by polymerase chain reaction (PCR) and screened by DNA sequencing analysis for sequence variations. STATISTICAL ANALYSIS USED Comparison of allele frequencies between patient and control groups was determined using a c(2) test. RESULTS AND CONCLUSIONS Total five DNA sequence variations were identified, three in exonic regions (c.643A > G, rs211035), (c.T > A, rs424740), and (c.C > T, rs418210) and two in intronic regions (c.751 + 41A > G, rs211034) and (c.751 + 52G > A, rs 34281163). Allele frequencies of variants identified in this study did not differ between patients and normal controls. Thus, we conclude that GABRG2 gene may not be playing significant role in the development of epilepsy or as a susceptibility gene in patients with MTLE in Indian population.
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Affiliation(s)
- Aparna Banerjee Dixit
- Center for Excellence in Epilepsy, A joint National Brain Research Centre-All Institute of Medical Sciences Collaboration, National Brain Research Centre, Manesar, Haryana, India
| | - Jyotirmoy Banerjee
- Center for Excellence in Epilepsy, A joint National Brain Research Centre-All Institute of Medical Sciences Collaboration, National Brain Research Centre, Manesar, Haryana, India
| | - Abuzar Ansari
- Department of Neurosurgery, All Institute of Medical Sciences, New Delhi, India
| | - Manjari Tripathi
- Department of Neurology, All Institute of Medical Sciences, New Delhi, India
| | - Sarat P Chandra
- Department of Neurosurgery, All Institute of Medical Sciences, New Delhi, India
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Schutte SS, Schutte RJ, Barragan EV, O'Dowd DK. Model systems for studying cellular mechanisms of SCN1A-related epilepsy. J Neurophysiol 2016; 115:1755-66. [PMID: 26843603 DOI: 10.1152/jn.00824.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 01/22/2016] [Indexed: 11/22/2022] Open
Abstract
Mutations in SCN1A, the gene encoding voltage-gated sodium channel NaV1.1, cause a spectrum of epilepsy disorders that range from genetic epilepsy with febrile seizures plus to catastrophic disorders such as Dravet syndrome. To date, more than 1,250 mutations in SCN1A have been linked to epilepsy. Distinct effects of individual SCN1A mutations on neuronal function are likely to contribute to variation in disease severity and response to treatment in patients. Several model systems have been used to explore seizure genesis in SCN1A epilepsies. In this article we review what has been learned about cellular mechanisms and potential new therapies from these model systems, with a particular emphasis on the novel model system of knock in Drosophila and a look toward the future with expanded use of patient-specific induced pluripotent stem cell-derived neurons.
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Affiliation(s)
- Soleil S Schutte
- Department of Developmental and Cell Biology and Department of Anatomy and Neurobiology, University of California, Irvine, California
| | - Ryan J Schutte
- Department of Developmental and Cell Biology and Department of Anatomy and Neurobiology, University of California, Irvine, California
| | - Eden V Barragan
- Department of Developmental and Cell Biology and Department of Anatomy and Neurobiology, University of California, Irvine, California
| | - Diane K O'Dowd
- Department of Developmental and Cell Biology and Department of Anatomy and Neurobiology, University of California, Irvine, California
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Zang Z, Li S, Zhang W, Chen X, Zheng D, Shu H, Guo W, Zhao B, Shen K, Wei Y, Zheng X, Liu S, Yang H. Expression Patterns of TRPC1 in Cortical Lesions from Patients with Focal Cortical Dysplasia. J Mol Neurosci 2015; 57:265-72. [PMID: 26280213 DOI: 10.1007/s12031-015-0615-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 06/30/2015] [Indexed: 02/05/2023]
Abstract
Focal cortical dysplasia (FCD) is known as a common cause of chronic refractory epilepsy, but the underlying mechanisms of the factors that lead to FCD-related epilepsy are unclear. Previous studies have shown that canonical transient receptor potential channels (TRPCs) might be involved in the process of epileptogenesis. Canonical transient receptor potential channel 1 (TRPC1), which is ubiquitously expressed in the brain, has been shown to be involved in epileptiform bust firing in knockout mice. In this study, we examined the expression of TRPC1 in FCD type Ia (FCDIa), FCD type IIa (FCDIIa), and FCD type IIb (FCDIIb) surgical specimens from patients and age-matched autopsy control samples. Real-time quantitative PCR and western blotting indicated that TRPC1 mRNA and protein levels were increased in FCDIa, FCDIIa, and FCDIIb samples compared to control samples. Immunohistochemistry results revealed that TRPC1 was mainly distributed in microcolumns, dysmorphic neurons, and balloon cells. Further double immunofluorescent staining showed that TRPC1 was co-localized with glutamatergic and GABAergic markers. Taken together, our results demonstrate that the overexpression and specific cellular location of TRPC1 might be related to the epileptogenesis of FCD.
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Affiliation(s)
- Zhenle Zang
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Song Li
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Wei Zhang
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Xin Chen
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Dahai Zheng
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Haifeng Shu
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.,Department of Neurosurgery, Chengdu Military General Hospital of PLA, Chengdu, Sichuan, 610083, China
| | - Wei Guo
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Bangyun Zhao
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Kaifeng Shen
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - YuJia Wei
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Xin Zheng
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China
| | - Shiyong Liu
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
| | - Hui Yang
- Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
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Qu J, Yang ZQ, Zhang Y, Mao CX, Wang ZB, Mao XY, Zhou BT, Yin JY, He H, Long HY, Gong JE, Xiao B, Zhou HH, Liu ZQ. Common variants of ATP1A3 but not ATP1A2 are associated with Chinese genetic generalized epilepsies. J Neurol Sci 2015; 354:56-62. [DOI: 10.1016/j.jns.2015.04.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 04/01/2015] [Accepted: 04/27/2015] [Indexed: 12/26/2022]
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49
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Impaired action potential initiation in GABAergic interneurons causes hyperexcitable networks in an epileptic mouse model carrying a human Na(V)1.1 mutation. J Neurosci 2015; 34:14874-89. [PMID: 25378155 DOI: 10.1523/jneurosci.0721-14.2014] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Mutations in SCN1A and other ion channel genes can cause different epileptic phenotypes, but the precise mechanisms underlying the development of hyperexcitable networks are largely unknown. Here, we present a multisystem analysis of an SCN1A mouse model carrying the NaV1.1-R1648H mutation, which causes febrile seizures and epilepsy in humans. We found a ubiquitous hypoexcitability of interneurons in thalamus, cortex, and hippocampus, without detectable changes in excitatory neurons. Interestingly, somatic Na(+) channels in interneurons and persistent Na(+) currents were not significantly changed. Instead, the key mechanism of interneuron dysfunction was a deficit of action potential initiation at the axon initial segment that was identified by analyzing action potential firing. This deficit increased with the duration of firing periods, suggesting that increased slow inactivation, as recorded for recombinant mutated channels, could play an important role. The deficit in interneuron firing caused reduced action potential-driven inhibition of excitatory neurons as revealed by less frequent spontaneous but not miniature IPSCs. Multiple approaches indicated increased spontaneous thalamocortical and hippocampal network activity in mutant mice, as follows: (1) more synchronous and higher-frequency firing was recorded in primary neuronal cultures plated on multielectrode arrays; (2) thalamocortical slices examined by field potential recordings revealed spontaneous activities and pathological high-frequency oscillations; and (3) multineuron Ca(2+) imaging in hippocampal slices showed increased spontaneous neuronal activity. Thus, an interneuron-specific generalized defect in action potential initiation causes multisystem disinhibition and network hyperexcitability, which can well explain the occurrence of seizures in the studied mouse model and in patients carrying this mutation.
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50
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Association of GABRA6 1519 T>C (rs3219151) and Synapsin II (rs37733634) gene polymorphisms with the development of idiopathic generalized epilepsy. Epilepsy Res 2014; 108:1267-73. [DOI: 10.1016/j.eplepsyres.2014.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 06/18/2014] [Accepted: 07/09/2014] [Indexed: 11/22/2022]
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