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LaCoursiere CM, Ullmann JF, Koh HY, Turner L, Baker CM, Robens B, Shao W, Rotenberg A, McGraw CM, Poduri AH. Zebrafish models of candidate human epilepsy-associated genes provide evidence of hyperexcitability. iScience 2024; 27:110172. [PMID: 39021799 PMCID: PMC11253282 DOI: 10.1016/j.isci.2024.110172] [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] [Received: 02/16/2024] [Revised: 05/13/2024] [Accepted: 05/31/2024] [Indexed: 07/20/2024] Open
Abstract
Hundreds of novel candidate human epilepsy-associated genes have been identified thanks to advancements in next-generation sequencing and large genome-wide association studies, but establishing genetic etiology requires functional validation. We generated a list of >2,200 candidate epilepsy-associated genes, of which 48 were developed into stable loss-of-function (LOF) zebrafish models. Of those 48, evidence of seizure-like behavior was present in 5 (arfgef1, kcnd2, kcnv1, ubr5, and wnt8b). Further characterization provided evidence for epileptiform activity via electrophysiology in kcnd2 and wnt8b mutants. Additionally, arfgef1 and wnt8b mutants showed a decrease in the number of inhibitory interneurons in the optic tectum of larval animals. Further, RNA sequencing (RNA-seq) revealed convergent transcriptional abnormalities between mutant lines, consistent with their developmental defects and hyperexcitable phenotypes. These zebrafish models provide strongest experimental evidence supporting the role of ARFGEF1, KCND2, and WNT8B in human epilepsy and further demonstrate the utility of this model system for evaluating candidate human epilepsy genes.
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Affiliation(s)
- Christopher Mark LaCoursiere
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Jeremy F.P. Ullmann
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Hyun Yong Koh
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Departments of Neuroscience and Pediatrics, Division of Neurology and Developmental Neuroscience, BCM, Houston, TX 77030, USA
| | - Laura Turner
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Cristina M. Baker
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, 7034 Trondheim, Norway
| | - Barbara Robens
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Wanqing Shao
- Research Computing, Department of Information Technology, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Alexander Rotenberg
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Christopher M. McGraw
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Annapurna H. Poduri
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
- Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
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2
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Dhureja M, Chaturvedi P, Choudhary A, Kumar P, Munshi A. Molecular Insights of Drug Resistance in Epilepsy: Multi-omics Unveil. Mol Neurobiol 2024:10.1007/s12035-024-04220-6. [PMID: 38753128 DOI: 10.1007/s12035-024-04220-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 05/03/2024] [Indexed: 06/12/2024]
Abstract
Epilepsy is a devastating neurological disorder mainly associated with impaired synchronic discharge that leads to sensory, motor, and psychomotor impairments. Till now, about 30 anti-seizure medications (ASMs) have been approved for the management of epilepsy, yet one-third of individuals still have uncontrollable epilepsy and develop resistance. Drug resistance epilepsy (DRE) is defined as the condition where two ASMs fail to control the seizure in epileptic patients. The leading cause of the resistance was the extended use of ASMs. According to various studies, alterations in some genes and their expressions, along with specific metabolic impairments, are suggested to be associated with ASMs resistance and DRE pathophysiology. Several factors aid in the pathophysiology of DRE, such as alterations in protein-encoding genes such as neurotransmitter receptors, drug transporters, ion channels, and drug targets. Furthermore, the altered metabolite levels of metabolites implicated in neurotransmitter signaling, energetic pathways, oxidative stress, and neuroinflammatory signaling differentiate the epileptic patient from the DRE patient. Various DRE biomarkers can be identified using the "integrated omics approach," which includes the study of genomics, transcriptomics, and metabolomics. The current review has been compiled to understand the pathophysiological mechanisms of DRE by focusing on genomics, transcriptomics, and metabolomics. An effort has also been made to identify the therapeutic targets based on identifying significant markers by a multi-omics approach. This has the potential to develop novel therapeutic interventions in the future.
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Affiliation(s)
- Maanvi Dhureja
- Department of Pharmacology, Central University of Punjab, Bathinda, India
| | - Pragya Chaturvedi
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India
| | - Anita Choudhary
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India
| | - Puneet Kumar
- Department of Pharmacology, Central University of Punjab, Bathinda, India.
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicines, Central University of Punjab, Bathinda, India.
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LaCoursiere CM, Ullmann JFP, Koh HY, Turner L, Baker CM, Robens B, Shao W, Rotenberg A, McGraw CM, Poduri A. Zebrafish models of candidate human epilepsy-associated genes provide evidence of hyperexcitability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.07.579190. [PMID: 38370728 PMCID: PMC10871320 DOI: 10.1101/2024.02.07.579190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Hundreds of novel candidate human epilepsy-associated genes have been identified thanks to advancements in next-generation sequencing and large genome-wide association studies, but establishing genetic etiology requires functional validation. We generated a list of >2200 candidate epilepsy-associated genes, of which 81 were determined suitable for the generation of loss-of-function zebrafish models via CRISPR/Cas9 gene editing. Of those 81 crispants, 48 were successfully established as stable mutant lines and assessed for seizure-like swim patterns in a primary F2 screen. Evidence of seizure-like behavior was present in 5 (arfgef1, kcnd2, kcnv1, ubr5, wnt8b) of the 48 mutant lines assessed. Further characterization of those 5 lines provided evidence for epileptiform activity via electrophysiology in kcnd2 and wnt8b mutants. Additionally, arfgef1 and wnt8b mutants showed a decrease in the number of inhibitory interneurons in the optic tectum of larval animals. Furthermore, RNAseq revealed convergent transcriptional abnormalities between mutant lines, consistent with their developmental defects and hyperexcitable phenotypes. These zebrafish models provide strongest experimental evidence supporting the role of ARFGEF1, KCND2, and WNT8B in human epilepsy and further demonstrate the utility of this model system for evaluating candidate human epilepsy genes.
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Affiliation(s)
- Christopher Mark LaCoursiere
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Jeremy F P Ullmann
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Hyun Yong Koh
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Departments of Neuroscience and Pediatrics, Division of Neurology and Developmental Neuroscience, BCM, Houston, Texas, USA
| | - Laura Turner
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Cristina M Baker
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - Barbara Robens
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Wanqing Shao
- Research Computing, Department of Information Technology, Boston Children's Hospital, Boston, MA, USA
| | - Alexander Rotenberg
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Christopher M McGraw
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Annapurna Poduri
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
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Li Y, Zhang C, Peng G. Ap4s1 truncation leads to axonal defects in a zebrafish model of spastic paraplegia 52. Int J Dev Neurosci 2023; 83:753-764. [PMID: 37767851 DOI: 10.1002/jdn.10303] [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: 04/17/2023] [Revised: 08/11/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
Biallelic mutations in AP4S1, the σ4 subunit of the adaptor protein complex 4 (AP-4), lead to autosomal recessive spastic paraplegia 52 (SPG52). It is a subtype of AP-4-associated hereditary spastic paraplegia (AP-4-HSP), a complex childhood-onset neurogenetic disease characterized by progressive spastic paraplegia of the lower limbs. This disease has so far lacked effective treatment, in part due to a lack of suitable animal models. Here, we used CRISPR/Cas9 technology to generate a truncation mutation in the ap4s1 gene in zebrafish. The ap4s1 truncation led to motor impairment, delayed neurodevelopment, and distal axonal degeneration. This animal model is useful for further research into AP-4 and AP-4-HSP.
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Affiliation(s)
- Yiduo Li
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, China
| | - Cuizhen Zhang
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, China
| | - Gang Peng
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, China
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5
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D'Amora M, Galgani A, Marchese M, Tantussi F, Faraguna U, De Angelis F, Giorgi FS. Zebrafish as an Innovative Tool for Epilepsy Modeling: State of the Art and Potential Future Directions. Int J Mol Sci 2023; 24:ijms24097702. [PMID: 37175408 PMCID: PMC10177843 DOI: 10.3390/ijms24097702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/20/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
This article discusses the potential of Zebrafish (ZF) (Danio Rerio), as a model for epilepsy research. Epilepsy is a neurological disorder affecting both children and adults, and many aspects of this disease are still poorly understood. In vivo and in vitro models derived from rodents are the most widely used for studying both epilepsy pathophysiology and novel drug treatments. However, researchers have recently obtained several valuable insights into these two fields of investigation by studying ZF. Despite the relatively simple brain structure of these animals, researchers can collect large amounts of data in a much shorter period and at lower costs compared to classical rodent models. This is particularly useful when a large number of candidate antiseizure drugs need to be screened, and ethical issues are minimized. In ZF, seizures have been induced through a variety of chemoconvulsants, primarily pentylenetetrazol (PTZ), kainic acid (KA), and pilocarpine. Furthermore, ZF can be easily genetically modified to test specific aspects of monogenic forms of human epilepsy, as well as to discover potential convulsive phenotypes in monogenic mutants. The article reports on the state-of-the-art and potential new fields of application of ZF research, including its potential role in revealing epileptogenic mechanisms, rather than merely assessing iatrogenic acute seizure modulation.
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Affiliation(s)
- Marta D'Amora
- Istituto Italiano di Tecnologia, 16163 Genova, Italy
- Department of Biology, University of Pisa, 56125 Pisa, Italy
| | - Alessandro Galgani
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy
| | - Maria Marchese
- Molecular Medicine and Neurobiology-ZebraLab, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy
| | | | - Ugo Faraguna
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy
- Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy
| | | | - Filippo Sean Giorgi
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy
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6
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Developing Novel Experimental Models of m-TORopathic Epilepsy and Related Neuropathologies: Translational Insights from Zebrafish. Int J Mol Sci 2023; 24:ijms24021530. [PMID: 36675042 PMCID: PMC9866103 DOI: 10.3390/ijms24021530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/15/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is an important molecular regulator of cell growth and proliferation. Brain mTOR activity plays a crucial role in synaptic plasticity, cell development, migration and proliferation, as well as memory storage, protein synthesis, autophagy, ion channel expression and axonal regeneration. Aberrant mTOR signaling causes a diverse group of neurological disorders, termed 'mTORopathies'. Typically arising from mutations within the mTOR signaling pathway, these disorders are characterized by cortical malformations and other neuromorphological abnormalities that usually co-occur with severe, often treatment-resistant, epilepsy. Here, we discuss recent advances and current challenges in developing experimental models of mTOR-dependent epilepsy and other related mTORopathies, including using zebrafish models for studying these disorders, as well as outline future directions of research in this field.
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Iffland PH, Everett ME, Cobb-Pitstick KM, Bowser LE, Barnes AE, Babus JK, Romanowski AJ, Baybis M, Elziny S, Puffenberger EG, Gonzaga-Jauregui C, Poulopoulos A, Carson VJ, Crino PB. NPRL3 loss alters neuronal morphology, mTOR localization, cortical lamination and seizure threshold. Brain 2022; 145:3872-3885. [PMID: 35136953 PMCID: PMC10200289 DOI: 10.1093/brain/awac044] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/10/2021] [Accepted: 12/10/2021] [Indexed: 08/13/2023] Open
Abstract
Mutations in nitrogen permease regulator-like 3 (NPRL3), a component of the GATOR1 complex within the mTOR pathway, are associated with epilepsy and malformations of cortical development. Little is known about the effects of NPRL3 loss on neuronal mTOR signalling and morphology, or cerebral cortical development and seizure susceptibility. We report the clinical phenotypic spectrum of a founder NPRL3 pedigree (c.349delG, p.Glu117LysFS; n = 133) among Old Order Mennonites dating to 1727. Next, as a strategy to define the role of NPRL3 in cortical development, CRISPR/Cas9 Nprl3 knockout in Neuro2a cells in vitro and in foetal mouse brain in vivo was used to assess the effects of Nprl3 knockout on mTOR activation, subcellular mTOR localization, nutrient signalling, cell morphology and aggregation, cerebral cortical cytoarchitecture and network integrity. The NPRL3 pedigree exhibited an epilepsy penetrance of 28% and heterogeneous clinical phenotypes with a range of epilepsy semiologies, i.e. focal or generalized onset, brain imaging abnormalities, i.e. polymicrogyria, focal cortical dysplasia or normal imaging, and EEG findings, e.g. focal, multi-focal or generalized spikes, focal or generalized slowing. Whole exome analysis comparing a seizure-free group (n = 37) to those with epilepsy (n = 24) to search for gene modifiers for epilepsy did not identify a unique genetic modifier that explained the variability in seizure penetrance in this cohort. Nprl3 knockout in vitro caused mTOR pathway hyperactivation, cell soma enlargement and the formation of cellular aggregates seen in time-lapse videos that were prevented with the mTOR inhibitors rapamycin or torin1. In Nprl3 knockout cells, mTOR remained localized on the lysosome in a constitutively active conformation, as evidenced by phosphorylation of ribosomal S6 and 4E-BP1 proteins, even under nutrient starvation (amino acid-free) conditions, demonstrating that Nprl3 loss decouples mTOR activation from neuronal metabolic state. To model human malformations of cortical development associated with NPRL3 variants, we created a focal Nprl3 knockout in foetal mouse cortex by in utero electroporation and found altered cortical lamination and white matter heterotopic neurons, effects which were prevented with rapamycin treatment. EEG recordings showed network hyperexcitability and reduced seizure threshold to pentylenetetrazol treatment. NPRL3 variants are linked to a highly variable clinical phenotype which we propose results from mTOR-dependent effects on cell structure, cortical development and network organization.
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Affiliation(s)
- Philip H Iffland
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | | | | | | | - Allan E Barnes
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | - Janice K Babus
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | - Andrea J Romanowski
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | - Marianna Baybis
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | - Soad Elziny
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | | | | | - Alexandros Poulopoulos
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
| | | | - Peter B Crino
- University of Maryland School of Medicine Departments of Neurology and Pharmacology, Baltimore, MD 21201, USA
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8
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Chen X, Liu F, Chen K, Wang Y, Yin A, Kang X, Yang S, Zhao H, Dong S, Li Y, Chen J, Wu Y. TFG mutation induces haploinsufficiency and drives axonal Charcot-Marie-Tooth disease by causing neurite degeneration. CNS Neurosci Ther 2022; 28:2076-2089. [PMID: 35986567 PMCID: PMC9627391 DOI: 10.1111/cns.13943] [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] [Received: 12/16/2021] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 02/06/2023] Open
Abstract
AIMS TFG-related axonal Charcot-Marie-Tooth (CMT) disease is a late-onset, autosomal dominant, hereditary motor, and sensory neuropathy characterized by slowly progressive weakness and atrophy of the distal muscles. The objective of this study was to determine the common pathogenic mechanism of TFG-related CMT type 2 (CMT2) caused by different mutations and establish a direct association between TFG haploinsufficiency and neurodegeneration. METHODS Three individuals carrying the TFG p.G269V mutation but with varying disease durations were studied. The effect of the p.G269V mutation was confirmed by analyzing protein samples extracted from the blood of two individuals. The functional consequences of both CMT2 mutant gene products were evaluated in vitro. The effect of TFG deficiency in the nervous system was examined using zebrafish models and cultured mouse neurons. RESULTS Overexpression of p.G269V TFG failed to enhance soluble TFG levels by generating insoluble TFG aggregates. TFG deficiency disrupted neurite outgrowth and induced neuronal apoptosis both in vivo and in vitro and further impaired locomotor capacity in zebrafish, which was consistent with the phenotype in patients. Wnt signaling was activated as a protective factor in response to TFG deficiency. CONCLUSION CMT2-related TFG mutation induces TFG haploinsufficiency within cells and drives disease by causing progressive neurite degeneration.
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Affiliation(s)
- Xihui Chen
- Department of Biochemistry and Molecular Biology, School of Basic MedicineAir Force Medical UniversityXi'anChina,Shaanxi Provincial Key Laboratory of Clinic GeneticsAir Force Medical UniversityXi'anChina
| | - Fangfang Liu
- Department of Neurobiology, School of Basic MedicineAir Force Medical UniversityXi'anChina
| | - Kun Chen
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Centre, School of Basic MedicineAir Force Medical UniversityXi'anChina
| | - Yufeng Wang
- Department of Biochemistry and Molecular Biology, School of Basic MedicineAir Force Medical UniversityXi'anChina,Shaanxi Provincial Key Laboratory of Clinic GeneticsAir Force Medical UniversityXi'anChina,Medical GeneticsYan'an UniversityYan'anChina
| | - Anan Yin
- Department of Neurosurgery, Department of Plastic surgery, Xijing Institute of Clinical Neuroscience, Xijing HospitalAir Force Medical UniversityXi'anChina
| | - Xiaowei Kang
- Department of radiologyXi'an people's hospital (Xi'an fourth hospital)Xi'anChina
| | - Shanming Yang
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Centre, School of Basic MedicineAir Force Medical UniversityXi'anChina
| | - Hanwen Zhao
- Student BrigadeAir Force Medical UniversityXi'anChina
| | - Songqi Dong
- Student BrigadeAir Force Medical UniversityXi'anChina
| | - Yunqing Li
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Centre, School of Basic MedicineAir Force Medical UniversityXi'anChina
| | - Jing Chen
- Department of Anatomy, Histology and Embryology and K.K. Leung Brain Research Centre, School of Basic MedicineAir Force Medical UniversityXi'anChina
| | - Yuanming Wu
- Department of Biochemistry and Molecular Biology, School of Basic MedicineAir Force Medical UniversityXi'anChina,Shaanxi Provincial Key Laboratory of Clinic GeneticsAir Force Medical UniversityXi'anChina
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9
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Ochenkowska K, Herold A, Samarut É. Zebrafish Is a Powerful Tool for Precision Medicine Approaches to Neurological Disorders. Front Mol Neurosci 2022; 15:944693. [PMID: 35875659 PMCID: PMC9298522 DOI: 10.3389/fnmol.2022.944693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 06/17/2022] [Indexed: 12/17/2022] Open
Abstract
Personalized medicine is currently one of the most promising tools which give hope to patients with no suitable or no available treatment. Patient-specific approaches are particularly needed for common diseases with a broad phenotypic spectrum as well as for rare and yet-undiagnosed disorders. In both cases, there is a need to understand the underlying mechanisms and how to counteract them. Even though, during recent years, we have been observing the blossom of novel therapeutic techniques, there is still a gap to fill between bench and bedside in a patient-specific fashion. In particular, the complexity of genotype-to-phenotype correlations in the context of neurological disorders has dampened the development of successful disease-modifying therapeutics. Animal modeling of human diseases is instrumental in the development of therapies. Currently, zebrafish has emerged as a powerful and convenient model organism for modeling and investigating various neurological disorders. This model has been broadly described as a valuable tool for understanding developmental processes and disease mechanisms, behavioral studies, toxicity, and drug screening. The translatability of findings obtained from zebrafish studies and the broad prospect of human disease modeling paves the way for developing tailored therapeutic strategies. In this review, we will discuss the predictive power of zebrafish in the discovery of novel, precise therapeutic approaches in neurosciences. We will shed light on the advantages and abilities of this in vivo model to develop tailored medicinal strategies. We will also investigate the newest accomplishments and current challenges in the field and future perspectives.
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Affiliation(s)
- Katarzyna Ochenkowska
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.,Department of Neuroscience, Université de Montréal, Montreal, QC, Canada
| | - Aveeva Herold
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.,Department of Neuroscience, Université de Montréal, Montreal, QC, Canada
| | - Éric Samarut
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.,Department of Neuroscience, Université de Montréal, Montreal, QC, Canada.,Modelis Inc., Montreal, QC, Canada
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10
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Dougnon G, Matsui H. Modelling Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) Using Mice and Zebrafish. Int J Mol Sci 2022; 23:ijms23147550. [PMID: 35886894 PMCID: PMC9319972 DOI: 10.3390/ijms23147550] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 02/06/2023] Open
Abstract
Autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD) are two debilitating neurodevelopmental disorders. The former is associated with social impairments whereas the latter is associated with inattentiveness, hyperactivity, and impulsivity. There is recent evidence that both disorders are somehow related and that genes may play a large role in these disorders. Despite mounting human and animal research, the neurological pathways underlying ASD and ADHD are still not well understood. Scientists investigate neurodevelopmental disorders by using animal models that have high similarities in genetics and behaviours with humans. Mice have been utilized in neuroscience research as an excellent animal model for a long time; however, the zebrafish has attracted much attention recently, with an increasingly large number of studies using this model. In this review, we first discuss ASD and ADHD aetiology from a general point of view to their characteristics and treatments. We also compare mice and zebrafish for their similarities and discuss their advantages and limitations in neuroscience. Finally, we summarize the most recent and existing research on zebrafish and mouse models of ASD and ADHD. We believe that this review will serve as a unique document providing interesting information to date about these models, thus facilitating research on ASD and ADHD.
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11
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Specchio N, Pietrafusa N, Perucca E, Cross JH. New paradigms for the treatment of pediatric monogenic epilepsies: Progressing toward precision medicine. Epilepsy Behav 2022; 131:107961. [PMID: 33867301 DOI: 10.1016/j.yebeh.2021.107961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 03/24/2021] [Indexed: 12/25/2022]
Abstract
Despite the availability of 28 antiseizure medications (ASMs), one-third of people with epilepsy fail to achieve sustained freedom from seizures. Clinical outcome is even poorer for children with developmental and epileptic encephalopathies (DEEs), many of which are due to single-gene mutations. Discovery of causative genes, however, has paved the way to understanding the molecular mechanism underlying these epilepsies, and to the rational application, or development, of precision treatments aimed at correcting the specific functional defects or their consequences. This article provides an overview of current progress toward precision medicine (PM) in the management of monogenic pediatric epilepsies, by focusing on four different scenarios, namely (a) rational selection of ASMs targeting specifically the underlying pathogenetic mechanisms; (b) development of targeted therapies based on novel molecules; (c) use of dietary treatments or food constituents aimed at correcting specific metabolic defects; and (d) repurposing of medications originally approved for other indications. This article is part of the Special Issue "Severe Infantile Epilepsies".
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Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome, Italy.
| | - Nicola Pietrafusa
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS, Full Member of European Reference Network EpiCARE, Rome, Italy
| | - Emilio Perucca
- Department of Internal Medicine and Therapeutics, University of Pavia, Pavia, Italy
| | - J Helen Cross
- UCL NIHR BRC Great Ormond Street Institute of Child Health and Great Ormond Street Hospital for Children, London, UK
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12
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Dentel B, Angeles-Perez L, Ren C, Jakkamsetti V, Holley AJ, Caballero D, Oh E, Gibson J, Pascual JM, Huber KM, Tu BP, Tsai PT. Increased glycine contributes to synaptic dysfunction and early mortality in Nprl2 seizure model. iScience 2022; 25:104334. [PMID: 35602938 PMCID: PMC9118754 DOI: 10.1016/j.isci.2022.104334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 09/16/2021] [Accepted: 04/26/2022] [Indexed: 10/25/2022] Open
Abstract
Targeted therapies for epilepsies associated with the mTORC1 signaling negative regulator GATOR1 are lacking. NPRL2 is a subunit of the GATOR1 complex and mutations in GATOR1 subunits, including NPRL2, are associated with epilepsy. To delineate the mechanisms underlying NPRL2-related epilepsies, we created a mouse (Mus musculus) model with neocortical loss of Nprl2. Mutant mice have increased mTORC1 signaling and exhibit spontaneous seizures. They also display abnormal synaptic function characterized by increased evoked and spontaneous EPSC and decreased evoked and spontaneous IPSC frequencies, respectively. Proteomic and metabolomics studies of Nprl2 mutants revealed alterations in known epilepsy-implicated proteins and metabolic pathways, including increases in the neurotransmitter, glycine. Furthermore, glycine actions on the NMDA receptor contribute to the electrophysiological and survival phenotypes of these mice. Taken together, in this neuronal Nprl2 model, we delineate underlying molecular, metabolic, and electrophysiological mechanisms contributing to mTORC1-related epilepsy, providing potential therapeutic targets for epilepsy.
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Affiliation(s)
- Brianne Dentel
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | | | - Chongyu Ren
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Vikram Jakkamsetti
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Andrew J. Holley
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Daniel Caballero
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Emily Oh
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Jay Gibson
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Juan M. Pascual
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Kimberly M. Huber
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Benjamin P. Tu
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX 75235, USA
| | - Peter T. Tsai
- Department of Neurology, UT Southwestern Medical Center, Dallas, TX 75235, USA
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75235, USA
- Departments of Pediatrics and Psychiatry, UT Southwestern Medical Center, Dallas, TX 75235, USA
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13
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Loissell-Baltazar YA, Dokudovskaya S. SEA and GATOR 10 Years Later. Cells 2021; 10:cells10102689. [PMID: 34685669 PMCID: PMC8534245 DOI: 10.3390/cells10102689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/30/2021] [Accepted: 10/03/2021] [Indexed: 12/17/2022] Open
Abstract
The SEA complex was described for the first time in yeast Saccharomyces cerevisiae ten years ago, and its human homologue GATOR complex two years later. During the past decade, many advances on the SEA/GATOR biology in different organisms have been made that allowed its role as an essential upstream regulator of the mTORC1 pathway to be defined. In this review, we describe these advances in relation to the identification of multiple functions of the SEA/GATOR complex in nutrient response and beyond and highlight the consequence of GATOR mutations in cancer and neurodegenerative diseases.
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14
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Wang T, Zhou M, Zhang Q, Zhang C, Peng G. ubtor Mutation Causes Motor Hyperactivity by Activating mTOR Signaling in Zebrafish. Neurosci Bull 2021; 37:1658-1670. [PMID: 34309811 PMCID: PMC8643380 DOI: 10.1007/s12264-021-00755-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/08/2021] [Indexed: 01/20/2023] Open
Abstract
Mechanistic target of rapamycin (mTOR) signaling governs important physiological and pathological processes key to cellular life. Loss of mTOR negative regulators and subsequent over-activation of mTOR signaling are major causes underlying epileptic encephalopathy. Our previous studies showed that UBTOR/KIAA1024/MINAR1 acts as a negative regulator of mTOR signaling, but whether UBTOR plays a role in neurological diseases remains largely unknown. We therefore examined a zebrafish model and found that ubtor disruption caused increased spontaneous embryonic movement and neuronal activity in spinal interneurons, as well as the expected hyperactivation of mTOR signaling in early zebrafish embryos. In addition, mutant ubtor larvae showed increased sensitivity to the convulsant pentylenetetrazol, and both the motor activity and the neuronal activity were up-regulated. These phenotypic abnormalities in zebrafish embryos and larvae were rescued by treatment with the mTORC1 inhibitor rapamycin. Taken together, our findings show that ubtor regulates motor hyperactivity and epilepsy-like behaviors by elevating neuronal activity and activating mTOR signaling.
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Affiliation(s)
- Tiantian Wang
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Mingshan Zhou
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Quan Zhang
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Cuizhen Zhang
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Gang Peng
- State Key Laboratory of Medical Neurobiology, Ministry of Education Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, 200032, China.
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15
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Garbinato C, Lima-Rezende CA, Schneider SE, Pedroso J, Dos Santos AE, Petry F, Aguiar GPS, Müller LG, Lanza M, Piato A, Vladimir Oliveira J, Siebel AM. Investigation on the Anticonvulsant Potential of Luteolin and Micronized Luteolin in Adult Zebrafish (Danio rerio). Neurochem Res 2021; 46:3025-3034. [PMID: 34309774 DOI: 10.1007/s11064-021-03409-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/09/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022]
Abstract
Epilepsy affects around 50 million people worldwide, and an important number of patients (30%) fail to respond to any available antiepileptic drug. Previous studies have shown that luteolin presents a promising potential as an anticonvulsant. On the other hand, different studies showed that luteolin does not promote anticonvulsant effects. Therefore, there is a lack of consensus about the use of luteolin for seizure control. Luteolin low bioavailability could be a limiting factor to obtain better results. Attractively, micronization technology has been applied to improve flavonoids bioavailability. Thus, the present study aimed to investigate the effects of luteolin on its raw form and micronized luteolin in a PTZ-induced seizure model in adult zebrafish (Danio rerio). Our results demonstrate that luteolin and micronized luteolin did not block PTZ-induced seizures in adult zebrafish. Also, luteolin and micronized luteolin did not provoke behavioral changes. Finally, our results show that 24 h after seizure occurrence, no changes were detected for p70S6Kb, interleukin 1β, and caspase-3 transcript levels. Altogether, we failed to observe an anticonvulsant potential of luteolin in adult zebrafish, even in its micronized form. However, we recommend new studies to investigate luteolin benefits in epilepsy.
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Affiliation(s)
- Cristiane Garbinato
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Cássia Alves Lima-Rezende
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil.,División Ornitología, Museo Argentino de Ciencias Naturales, Buenos Aires, Argentina
| | - Sabrina Ester Schneider
- Curso de Ciências Biológicas, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Jefferson Pedroso
- Curso de Ciências Biológicas, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Aline E Dos Santos
- Departamento de Engenharia Química e de Alimentos, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Fernanda Petry
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Gean Pablo S Aguiar
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Liz Girardi Müller
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil
| | - Marcelo Lanza
- Departamento de Engenharia Química e de Alimentos, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Angelo Piato
- Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - J Vladimir Oliveira
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil.,Departamento de Engenharia Química e de Alimentos, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Anna Maria Siebel
- Programa de Pós-Graduação em Ciências Ambientais, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil. .,Curso de Ciências Biológicas, Universidade Comunitária da Região de Chapecó, Chapecó, SC, Brazil.
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16
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Shcheglovitov A, Peterson RT. Screening Platforms for Genetic Epilepsies-Zebrafish, iPSC-Derived Neurons, and Organoids. Neurotherapeutics 2021; 18:1478-1489. [PMID: 34595731 PMCID: PMC8608971 DOI: 10.1007/s13311-021-01115-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2021] [Indexed: 02/04/2023] Open
Abstract
Recent advances in molecular and cellular engineering, such as human cell reprogramming, genome editing, and patient-specific organoids, have provided unprecedented opportunities for investigating human disorders in both animals and human-based models at an improved pace and precision. This progress will inevitably lead to the development of innovative drug-screening platforms and new patient-specific therapeutics. In this review, we discuss recent advances that have been made using zebrafish and human-induced pluripotent stem cell (iPSC)-derived neurons and organoids for modeling genetic epilepsies. We also provide our prospective on how these models can potentially be combined to build new screening platforms for antiseizure and antiepileptogenic drug discovery that harness the robustness and tractability of zebrafish models as well as the patient-specific genetics and biology of iPSC-derived neurons and organoids.
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17
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Praticò AD, Falsaperla R, Polizzi A, Ruggieri M. Monogenic Epilepsies: Channelopathies, Synaptopathies, mTorpathies, and Otheropathies. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractEpilepsy has been historically defined as the recurrence of two or more seizures, together with typical electroencephalogram (EEG) changes, and significant comorbidities, including cardiac and autonomic changes, injuries, intellectual disability, permanent brain damage, and higher mortality risk. Epilepsy may be the consequence of several causes, including genetic anomalies, structural brain malformations, hypoxic–ischemic encephalopathy, brain tumors, drugs, and all contributing factors to the imbalance between excitatory and inhibitory neurons and modulatory interneurons which in turn provoke abnormal, simultaneous electric discharge(s) involving part, or all the brain. In the pregenetic, pregenomic era, in most cases, the exact cause of such neuronal/interneuronal disequilibrium remained unknown and the term “idiopathic epilepsy” was used to define all the epilepsies without cause. At the same time, some specific epileptic syndromes were indicated by the eponym of the first physician who originally described the condition (e.g., the West syndrome, Dravet syndrome, Ohtahara syndrome, and Lennox–Gastaut syndrome) or by some characteristic clinical features (e.g., nocturnal frontal lobe epilepsy, absence epilepsy, and epilepsy and mental retardation limited to females). In many of these occurrences, the distinct epileptic syndrome was defined mainly by its most relevant clinical feature (e.g., seizure semiology), associated comorbidities, and EEGs patterns. Since the identification of the first epilepsy-associated gene (i.e., CHRNA4 gene: cholinergic receptor neuronal nicotinic α polypeptide 4), one of the genes responsible for autosomal dominant nocturnal frontal lobe epilepsy (currently known as sleep-related hypermotor epilepsy) in 1995, the field of epilepsy and the history of epilepsy gene discoveries have gone through at least three different stages as follows: (1) an early stage of relentless gene discovery in monogenic familial epilepsy syndromes; (2) a relatively quiescent and disappointing period characterized by largely negative genome-wide association candidate gene studies; and (3) a genome-wide era in which large-scale molecular genetic studies have led to the identification of several novel epilepsy genes, especially in sporadic forms of epilepsy. As of 2021, more than 150 epilepsy-associated genes or loci are listed in the Online Mendelian Inheritance in Man database.
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Affiliation(s)
- Andrea D. Praticò
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | - Agata Polizzi
- Chair of Pediatrics, Department of Educational Sciences, University of Catania, Catania, Italy
| | - Martino Ruggieri
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
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18
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Nguyen LH, Bordey A. Convergent and Divergent Mechanisms of Epileptogenesis in mTORopathies. Front Neuroanat 2021; 15:664695. [PMID: 33897381 PMCID: PMC8064518 DOI: 10.3389/fnana.2021.664695] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 03/17/2021] [Indexed: 12/30/2022] Open
Abstract
Hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1) due to mutations in genes along the PI3K-mTOR pathway and the GATOR1 complex causes a spectrum of neurodevelopmental disorders (termed mTORopathies) associated with malformation of cortical development and intractable epilepsy. Despite these gene variants’ converging impact on mTORC1 activity, emerging findings suggest that these variants contribute to epilepsy through both mTORC1-dependent and -independent mechanisms. Here, we review the literature on in utero electroporation-based animal models of mTORopathies, which recapitulate the brain mosaic pattern of mTORC1 hyperactivity, and compare the effects of distinct PI3K-mTOR pathway and GATOR1 complex gene variants on cortical development and epilepsy. We report the outcomes on cortical pyramidal neuronal placement, morphology, and electrophysiological phenotypes, and discuss some of the converging and diverging mechanisms responsible for these alterations and their contribution to epileptogenesis. We also discuss potential therapeutic strategies for epilepsy, beyond mTORC1 inhibition with rapamycin or everolimus, that could offer personalized medicine based on the gene variant.
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Affiliation(s)
- Lena H Nguyen
- Department of Neurosurgery, Yale School of Medicine, Yale University, New Haven, CT, United States.,Department of Cellular & Molecular Physiology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Angélique Bordey
- Department of Neurosurgery, Yale School of Medicine, Yale University, New Haven, CT, United States.,Department of Cellular & Molecular Physiology, Yale School of Medicine, Yale University, New Haven, CT, United States
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19
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Hu S, Yang T, Wang Y. Widespread labeling and genomic editing of the fetal central nervous system by in utero CRISPR AAV9-PHP.eB administration. Development 2021; 148:dev.195586. [PMID: 33334860 PMCID: PMC7847274 DOI: 10.1242/dev.195586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Accepted: 12/07/2020] [Indexed: 01/20/2023]
Abstract
Efficient genetic manipulation in the developing central nervous system is crucial for investigating mechanisms of neurodevelopmental disorders and the development of promising therapeutics. Common approaches including transgenic mice and in utero electroporation, although powerful in many aspects, have their own limitations. In this study, we delivered vectors based on the AAV9.PHP.eB pseudo-type to the fetal mouse brain, and achieved widespread and extensive transduction of neural cells. When AAV9.PHP.eB-coding gRNA targeting PogZ or Depdc5 was delivered to Cas9 transgenic mice, widespread gene knockout was also achieved at the whole brain level. Our studies provide a useful platform for studying brain development and devising genetic intervention for severe developmental diseases. Summary:In utero CRISPR AAV9-PHP.eB provides a powerful platform to efficiently manipulate gene expression in the developing CNS to investigate mechanisms of neurodevelopmental disorders.
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Affiliation(s)
- Shuntong Hu
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha 410013, China.,Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tao Yang
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yu Wang
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
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20
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Impact of predictive, preventive and precision medicine strategies in epilepsy. Nat Rev Neurol 2020; 16:674-688. [PMID: 33077944 DOI: 10.1038/s41582-020-0409-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2020] [Indexed: 12/15/2022]
Abstract
Over the last decade, advances in genetics, neuroimaging and EEG have enabled the aetiology of epilepsy to be identified earlier in the disease course than ever before. At the same time, progress in the study of experimental models of epilepsy has provided a better understanding of the mechanisms underlying the condition and has enabled the identification of therapies that target specific aetiologies. We are now witnessing the impact of these advances in our daily clinical practice. Thus, now is the time for a paradigm shift in epilepsy treatment from a reactive attitude, treating patients after the onset of epilepsy and the initiation of seizures, to a proactive attitude that is more broadly integrated into a 'P4 medicine' approach. This P4 approach, which is personalized, predictive, preventive and participatory, puts patients at the centre of their own care and, ultimately, aims to prevent the onset of epilepsy. This aim will be achieved by adapting epilepsy treatments not only to a given syndrome but also to a given patient and moving from the usual anti-seizure treatments to personalized treatments designed to target specific aetiologies. In this Review, we present the current state of this ongoing revolution, emphasizing the impact on clinical practice.
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21
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de Abreu MS, Genario R, Giacomini AC, Demin KA, Lakstygal AM, Amstislavskaya TG, Fontana BD, Parker MO, Kalueff AV. Zebrafish as a Model of Neurodevelopmental Disorders. Neuroscience 2020; 445:3-11. [DOI: 10.1016/j.neuroscience.2019.08.034] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 07/21/2019] [Accepted: 08/20/2019] [Indexed: 12/14/2022]
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22
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Gawel K, Langlois M, Martins T, van der Ent W, Tiraboschi E, Jacmin M, Crawford AD, Esguerra CV. Seizing the moment: Zebrafish epilepsy models. Neurosci Biobehav Rev 2020; 116:1-20. [PMID: 32544542 DOI: 10.1016/j.neubiorev.2020.06.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/20/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
Zebrafish are now widely accepted as a valuable animal model for a number of different central nervous system (CNS) diseases. They are suitable both for elucidating the origin of these disorders and the sequence of events culminating in their onset, and for use as a high-throughput in vivo drug screening platform. The availability of powerful and effective techniques for genome manipulation allows the rapid modelling of different genetic epilepsies and of conditions with seizures as a core symptom. With this review, we seek to summarize the current knowledge about existing epilepsy/seizures models in zebrafish (both pharmacological and genetic) and compare them with equivalent rodent and human studies. New findings obtained from the zebrafish models are highlighted. We believe that this comprehensive review will highlight the value of zebrafish as a model for investigating different aspects of epilepsy and will help researchers to use these models to their full extent.
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Affiliation(s)
- Kinga Gawel
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | | | - Teresa Martins
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Wietske van der Ent
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Ettore Tiraboschi
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Neurophysics Group, Center for Mind/Brain Sciences, University of Trento, Piazza Manifattura 1, Building 14, 38068, Rovereto, TN, Italy
| | - Maxime Jacmin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Alexander D Crawford
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg; Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | - Camila V Esguerra
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway.
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23
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Wasilewska I, Gupta RK, Wojtaś B, Palchevska O, Kuźnicki J. stim2b Knockout Induces Hyperactivity and Susceptibility to Seizures in Zebrafish Larvae. Cells 2020; 9:cells9051285. [PMID: 32455839 PMCID: PMC7291033 DOI: 10.3390/cells9051285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/13/2022] Open
Abstract
In neurons, stromal interaction molecule (STIM) proteins regulate store-operated Ca2+ entry (SOCE) and are involved in calcium signaling pathways. However, STIM activity in neurological diseases is unclear and should be clarified by studies that are performed in vivo rather than in cultured cells in vitro. The present study investigated the role of neuronal Stim2b protein in zebrafish. We generated stim2b knockout zebrafish, which were fertile and had a regular lifespan. Using various behavioral tests, we found that stim2b−/− zebrafish larvae were hyperactive compared with wild-type fish. The mutants exhibited increases in mobility and thigmotaxis and disruptions of phototaxis. They were also more sensitive to pentylenetetrazol and glutamate treatments. Using lightsheet microscopy, a higher average oscillation frequency and higher average amplitude of neuronal Ca2+ oscillations were observed in stim2b−/− larvae. RNA sequencing detected upregulation of the annexin 3a and gpr39 genes and downregulation of the rrm2, neuroguidin, and homer2 genes. The latter gene encodes a protein that is involved in several processes that are involved in Ca2+ homeostasis in neurons, including metabotropic glutamate receptors. We propose that Stim2b deficiency in neurons dysregulates SOCE and triggers changes in gene expression, thereby causing abnormal behavior, such as hyperactivity and susceptibility to seizures.
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Affiliation(s)
- Iga Wasilewska
- International Institute of Molecular and Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland; (I.W.); (R.K.G.); (O.P.)
| | - Rishikesh Kumar Gupta
- International Institute of Molecular and Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland; (I.W.); (R.K.G.); (O.P.)
| | - Bartosz Wojtaś
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, 02-093 Warsaw, Poland;
| | - Oksana Palchevska
- International Institute of Molecular and Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland; (I.W.); (R.K.G.); (O.P.)
| | - Jacek Kuźnicki
- International Institute of Molecular and Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland; (I.W.); (R.K.G.); (O.P.)
- Correspondence:
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24
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Bourefis AR, Campanari ML, Buee-Scherrer V, Kabashi E. Functional characterization of a FUS mutant zebrafish line as a novel genetic model for ALS. Neurobiol Dis 2020; 142:104935. [PMID: 32380281 DOI: 10.1016/j.nbd.2020.104935] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/22/2020] [Accepted: 04/29/2020] [Indexed: 12/12/2022] Open
Abstract
Mutations in Fused in sarcoma (FUS), an RNA-binding protein, are known to cause Amyotrophic Lateral Sclerosis (ALS). However, molecular mechanisms due to loss of FUS function remain unclear and controversial. Here, we report the characterization and phenotypic analysis of a deletion mutant of the unique FUS orthologue in zebrafish where Fus protein levels are depleted. The homozygous mutants displayed a reduced lifespan as well as impaired motor abilities associated with specific cellular deficits, including decreased motor neurons length and neuromuscular junctions (NMJ) fragmentation. Furthermore, we demonstrate that these cellular impairments are linked to the misregulation of mRNA expression of acetylcholine receptor (AChR) subunits and histone deacetylase 4, markers of denervation and reinnervation processes observed in ALS patients. In addition, fus loss of function alters tau transcripts favoring the expression of small tau isoforms. Overall, this new animal model extends our knowledge on FUS and supports the relevance of FUS loss of function in ALS physiopathology.
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Affiliation(s)
- Annis-Rayan Bourefis
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France; Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, INSERM Unité 1127, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche 7225 Institut du Cerveau et de la Moelle Épinière (ICM), 75013 Paris, France
| | - Maria-Letizia Campanari
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France; Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, INSERM Unité 1127, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche 7225 Institut du Cerveau et de la Moelle Épinière (ICM), 75013 Paris, France
| | | | - Edor Kabashi
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France; Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, INSERM Unité 1127, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche 7225 Institut du Cerveau et de la Moelle Épinière (ICM), 75013 Paris, France.
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25
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Ubiquitylation of the ER-Shaping Protein Lunapark via the CRL3KLHL12 Ubiquitin Ligase Complex. Cell Rep 2020; 31:107664. [DOI: 10.1016/j.celrep.2020.107664] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 01/16/2020] [Accepted: 04/28/2020] [Indexed: 11/19/2022] Open
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26
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Auvin S, Avbersek A, Bast T, Chiron C, Guerrini R, Kaminski RM, Lagae L, Muglia P, Cross JH. Drug Development for Rare Paediatric Epilepsies: Current State and Future Directions. Drugs 2020; 79:1917-1935. [PMID: 31734883 DOI: 10.1007/s40265-019-01223-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Rare diseases provide a challenge in the evaluation of new therapies. However, orphan drug development is of increasing interest because of the legislation enabling facilitated support by regulatory agencies through scientific advice, and the protection of the molecules with orphan designation. In the landscape of the rare epilepsies, very few syndromes, namely Dravet syndrome, Lennox-Gastaut syndrome and West syndrome, have been subject to orphan drug development. Despite orphan designations for rare epilepsies having dramatically increased in the past 10 years, the number of approved drugs remains limited and restricted to a handful of epilepsy syndromes. In this paper, we describe the current state of orphan drug development for rare epilepsies. We identified a large number of compounds currently under investigation, but mostly in the same rare epilepsy syndromes as in the past. A rationale for further development in rare epilepsies could be based on the match between the drug mechanisms of action and the knowledge of the causative gene mutation or by evidence from animal models. In case of the absence of strong pathophysiological hypotheses, exploratory/basket clinical studies could be helpful to identify a subpopulation that may benefit from the new drug. We provide some suggestions for future improvements in orphan drug development such as promoting paediatric drug investigations, better evaluation of the incidence and the prevalence, together with the natural history data, and the development of new primary outcomes.
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Affiliation(s)
- Stéphane Auvin
- PROTECT, INSERM U1141, Université de Paris, Paris, France. .,Service de Neurologie Pédiatrique, AP-HP, Hôpital Universitaire Robert-Debré, 48, Boulevard Sérurier, 75935, Paris Cedex 19, France.
| | | | - Thomas Bast
- The Kork Epilepsy Center, Kehl-Kork, Germany.,Medical Faculty of the University of Freiburg, Freiburg, Germany
| | - Catherine Chiron
- PROTECT, INSERM U1141, Université de Paris, Paris, France.,Service de Neurologie Pédiatrique, AP-HP, Hôpital Necker-Enfanst Malades, Paris, France
| | - Renzo Guerrini
- Neuroscience Department, Children's Hospital Anna Meyer-University of Florence, Florence, Italy
| | - Rafal M Kaminski
- UCB Pharma, Braine-l'Alleud, Belgium.,Roche Pharma Research and Early Development (pRED), Roche Innovation Center, Basel, Switzerland
| | - Lieven Lagae
- Department Development and Regeneration, Section Paediatric Neurology, University Hospitals, University of Leuven, Leuven, Belgium
| | | | - J Helen Cross
- UCL NIHR BRC Great Ormond Street Institute of Child Health, London, UK
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27
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Yuskaitis CJ, Rossitto LA, Gurnani S, Bainbridge E, Poduri A, Sahin M. Chronic mTORC1 inhibition rescues behavioral and biochemical deficits resulting from neuronal Depdc5 loss in mice. Hum Mol Genet 2020; 28:2952-2964. [PMID: 31174205 DOI: 10.1093/hmg/ddz123] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/31/2019] [Accepted: 06/04/2019] [Indexed: 01/05/2023] Open
Abstract
DEPDC5 is now recognized as one of the genes most often implicated in familial/inherited focal epilepsy and brain malformations. Individuals with pathogenic variants in DEPDC5 are at risk for epilepsy, associated neuropsychiatric comorbidities and sudden unexplained death in epilepsy. Depdc5flox/flox-Syn1Cre (Depdc5cc+) neuronal-specific Depdc5 knockout mice exhibit seizures and neuronal mTORC1 hyperactivation. It is not known if Depdc5cc+ mice have a hyperactivity/anxiety phenotype, die early from terminal seizures or whether mTOR inhibitors rescue DEPDC5-related seizures and associated comorbidities. Herein, we report that Depdc5cc+ mice were hyperactive in open-field testing but did not display anxiety-like behaviors on the elevated-plus maze. Unlike many other mTOR-related models, Depdc5cc+ mice had minimal epileptiform activity and rare seizures prior to seizure-induced death, as confirmed by video-EEG monitoring. Treatment with the mTORC1 inhibitor rapamycin starting after 3 weeks of age significantly prolonged the survival of Depdc5cc+ mice and partially rescued the behavioral hyperactivity. Rapamycin decreased the enlarged brain size of Depdc5cc+ mice with corresponding decrease in neuronal soma size. Loss of Depdc5 led to a decrease in the other GATOR1 protein levels (NPRL2 and NPRL3). Rapamycin failed to rescue GATOR1 protein levels but rather rescued downstream mTORC1 hyperactivity as measured by phosphorylation of S6. Collectively, our data provide the first evidence of behavioral alterations in mice with Depdc5 loss and support mTOR inhibition as a rational therapeutic strategy for DEPDC5-related epilepsy in humans.
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Affiliation(s)
- Christopher J Yuskaitis
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.,Division of Epilepsy and Clinical Neurophysiology and Epilepsy Genetics Program, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Leigh-Ana Rossitto
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Sarika Gurnani
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Elizabeth Bainbridge
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Annapurna Poduri
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.,Division of Epilepsy and Clinical Neurophysiology and Epilepsy Genetics Program, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Mustafa Sahin
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
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28
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De Fusco A, Cerullo MS, Marte A, Michetti C, Romei A, Castroflorio E, Baulac S, Benfenati F. Acute knockdown of Depdc5 leads to synaptic defects in mTOR-related epileptogenesis. Neurobiol Dis 2020; 139:104822. [PMID: 32113911 DOI: 10.1016/j.nbd.2020.104822] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/02/2020] [Accepted: 02/26/2020] [Indexed: 12/17/2022] Open
Abstract
DEP-domain containing 5 (DEPDC5) is part of the GATOR1 complex that functions as key inhibitor of the mechanistic target of rapamycin complex 1 (mTORC1). Loss-of-function mutations in DEPDC5 leading to mTOR hyperactivation have been identified as the most common cause of either lesional or non-lesional focal epilepsy. However, the precise mechanisms by which DEPDC5 loss-of-function triggers neuronal and network hyperexcitability are still unclear. In this study, we investigated the cellular mechanisms of hyperexcitability by comparing the constitutive heterozygous Depdc5 knockout mouse versus different levels of acute Depdc5 deletion (≈40% and ≈80% neuronal knockdown of Depdc5 protein) by RNA interference in primary cortical cultures. While heterozygous Depdc5+/- neurons have only a subtle phenotype, acutely knocked-down neurons exhibit a strong dose-dependent phenotype characterized by mTOR hyperactivation, increased soma size, dendritic arborization, excitatory synaptic transmission and intrinsic excitability. The robust synaptic phenotype resulting from the acute knockdown Depdc5 deficiency highlights the importance of the temporal dynamics of Depdc5 knockdown in triggering the phenotypic changes, reminiscent of the somatic second-hit mechanism in patients with focal cortical dysplasia. These findings uncover a novel synaptic phenotype that is causally linked to Depdc5 knockdown, highlighting the developmental role of Depdc5. Interestingly, the synaptic defect appears to affect only excitatory synapses, while inhibitory synapses develop normally. The increased frequency and amplitude of mEPSCs, paralleled by increased density of excitatory synapses and expression of glutamate receptors, may generate an excitation/inhibition imbalance that triggers epileptogenesis.
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Affiliation(s)
- Antonio De Fusco
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy; Department of Experimental Medicine, University of Genova, Viale Benedetto XV, 3, 16132 Genova, Italy
| | - Maria Sabina Cerullo
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy; Department of Experimental Medicine, University of Genova, Viale Benedetto XV, 3, 16132 Genova, Italy
| | - Antonella Marte
- Department of Experimental Medicine, University of Genova, Viale Benedetto XV, 3, 16132 Genova, Italy; IRCSS, Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132 Genova, Italy
| | - Caterina Michetti
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy; IRCSS, Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132 Genova, Italy
| | - Alessandra Romei
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy; Department of Experimental Medicine, University of Genova, Viale Benedetto XV, 3, 16132 Genova, Italy
| | - Enrico Castroflorio
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy
| | - Stephanie Baulac
- Sorbonne Université, UPMC Univ Paris 06, UMR S 1127, INSERM, U1127, CNRS, UMR 7225, Institut du Cerveau et de la Moelle épinière (ICM), Hôpital Pitié-Salpêtrière, F-75013 Paris, France
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Largo Rosanna Benzi 10, 16132 Genova, Italy; IRCSS, Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132 Genova, Italy.
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29
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Gawel K, Turski WA, van der Ent W, Mathai BJ, Kirstein-Smardzewska KJ, Simonsen A, Esguerra CV. Phenotypic Characterization of Larval Zebrafish (Danio rerio) with Partial Knockdown of the cacna1a Gene. Mol Neurobiol 2019; 57:1904-1916. [PMID: 31875924 PMCID: PMC7118054 DOI: 10.1007/s12035-019-01860-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 12/15/2019] [Indexed: 12/18/2022]
Abstract
The CACNA1A gene encodes the pore-forming α1 subunit of voltage-gated P/Q type Ca2+ channels (Cav2.1). Mutations in this gene, among others, have been described in patients and rodents suffering from absence seizures and episodic ataxia type 2 with/without concomitant seizures. In this study, we aimed for the first time to assess phenotypic and behavioral alterations in larval zebrafish with partial cacna1aa knockdown, placing special emphasis on changes in epileptiform-like electrographic discharges in larval brains. Whole-mount in situ hybridization analysis revealed expression of cacna1aa in the optic tectum and medulla oblongata of larval zebrafish at 4 and 5 days post-fertilization. Next, microinjection of two antisense morpholino oligomers (individually or in combination) targeting all splice variants of cacna1aa into fertilized zebrafish eggs resulted in dose-dependent mortality and decreased or absent touch response. Over 90% knockdown of cacna1aa on protein level induced epileptiform-like discharges in the optic tectum of larval zebrafish brains. Incubation of morphants with antiseizure drugs (sodium valproate, ethosuximide, lamotrigine, topiramate) significantly decreased the number and, in some cases, cumulative duration of epileptiform-like discharges. In this context, sodium valproate seemed to be the least effective. Carbamazepine did not affect the number and duration of epileptiform-like discharges. Altogether, our data indicate that cacna1aa loss-of-function zebrafish may be considered a new model of absence epilepsy and may prove useful both for the investigation of Cacna1a-mediated epileptogenesis and for in vivo drug screening.
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Affiliation(s)
- Kinga Gawel
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway.,Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | - Waldemar A Turski
- Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | - Wietske van der Ent
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Benan J Mathai
- Faculty of Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, 1112 Blindern, 0317, Oslo, Norway
| | - Karolina J Kirstein-Smardzewska
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Anne Simonsen
- Faculty of Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, 1112 Blindern, 0317, Oslo, Norway
| | - Camila V Esguerra
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway. .,School of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Oslo, Sem Sælandsvei 24, 0371, Oslo, Norway.
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30
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Depienne C, Ciura S, Trouillard O, Bouteiller D, Leitão E, Nava C, Keren B, Marie Y, Guegan J, Forlani S, Brice A, Anheim M, Agid Y, Krack P, Damier P, Viallet F, Houeto JL, Durif F, Vidailhet M, Worbe Y, Roze E, Kabashi E, Hartmann A. Association of Rare Genetic Variants in Opioid Receptors with Tourette Syndrome. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2019; 9:tre-09-693. [PMID: 31824749 PMCID: PMC6878848 DOI: 10.7916/tohm.v0.693] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 10/15/2019] [Indexed: 01/07/2023]
Abstract
Background Genes involved in Tourette syndrome (TS) remain largely unknown. We aimed to identify genetic factors contributing to TS in a French cohort of 120 individuals using a combination of hypothesis-driven and exome-sequencing approaches. Methods We first sequenced exons of SLITRK1-6 and HDC in the TS cohort and subsequently sequenced the exome of 12 individuals harboring rare variants in these genes to find additional rare variants contributing to the disorder under the hypothesis of oligogenic inheritance. We further screened three candidate genes (OPRK1, PCDH10, and NTSR2) preferentially expressed in the basal ganglia, and three additional genes involved in neurotensin and opioid signaling (OPRM1, NTS, and NTSR1), and compared variant frequencies in TS patients and 788 matched control individuals. We also investigated the impact of altering the expression of Oprk1 in zebrafish. Results Thirteen ultrarare missense variants of SLITRK1-6 and HDC were identified in 12 patients. Exome sequencing in these patients revealed rare possibly deleterious variants in 3,041 genes, 54 of which were preferentially expressed in the basal ganglia. Comparison of variant frequencies altering selected candidate genes in TS and control individuals revealed an excess of potentially disrupting variants in OPRK1, encoding the opioid kappa receptor, in TS patients. Accordingly, we show that downregulation of the Oprk1 orthologue in zebrafish induces a hyperkinetic phenotype in early development. Discussion These results support a heterogeneous and complex genetic etiology of TS, possibly involving rare variants altering the opioid pathway in some individuals, which could represent a novel therapeutic target in this disorder.
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Affiliation(s)
- Christel Depienne
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, DE
| | - Sorana Ciura
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Oriane Trouillard
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Delphine Bouteiller
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Elsa Leitão
- Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, DE
| | - Caroline Nava
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,Assistance Publique Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Département de Génétique, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Boris Keren
- Assistance Publique Hôpitaux de Paris (AP-HP), Hôpital Pitié-Salpêtrière, Département de Génétique, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Yannick Marie
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Justine Guegan
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Sylvie Forlani
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Alexis Brice
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Mathieu Anheim
- Service de neurologie, CHU de Strasbourg, Hôpital de Hautepierre, Avenue Molière, 67200 Strasbourg Strasbourg, FR
| | - Yves Agid
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Paul Krack
- Service de Neurologie, CHU de Grenoble, Avenue Maquis du Grésivaudan, 38700 La Tronche, FR.,Center for Movement Disorders, Inselspital, University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland
| | - Philippe Damier
- Service de Neurologie, CHU de Nantes, 5 Allée de l'Île Gloriette, 44093 Nantes, FR
| | - François Viallet
- Service de Neurologie, CRHU d'Aix-en-Provence, Avenue des Tamaris, 13100 Aix-en-Provence, FR
| | - Jean-Luc Houeto
- Service de Neurologie, CHU de Poitiers, 2 Rue de la Milétrie, 86021 Poitiers, FR
| | - Franck Durif
- Service de Neurologie, CHU de Clermont-Ferrand, CHU de Clermont-Ferrand, Hôpital Gabriel Montpied, 58 rue Montalembert, 63003 Clermont-Ferrand, FR
| | - Marie Vidailhet
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,Assistance Publique Hôpitaux de Paris (APHP), Hôpital Pitié-Salpêtrière, Département de Neurologie, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Yulia Worbe
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,Assistance Publique Hôpitaux de Paris (APHP), Hôpital Pitié-Salpêtrière, Département de Neurologie, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,AP-HP, Centre de Référence National Maladie Rare 'Syndrome Gilles de la Tourette', Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Emmanuel Roze
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,AP-HP, Centre de Référence National Maladie Rare 'Syndrome Gilles de la Tourette', Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Edor Kabashi
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
| | - Andreas Hartmann
- INSERM, U 1127, CNRS UMR 7225, Faculté de Médecine de Sorbonne Université, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,Assistance Publique Hôpitaux de Paris (APHP), Hôpital Pitié-Salpêtrière, Département de Neurologie, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR.,AP-HP, Centre de Référence National Maladie Rare 'Syndrome Gilles de la Tourette', Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l'Hôpital, 75013 Paris, FR
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31
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Iffland PH, Carson V, Bordey A, Crino PB. GATORopathies: The role of amino acid regulatory gene mutations in epilepsy and cortical malformations. Epilepsia 2019; 60:2163-2173. [PMID: 31625153 PMCID: PMC7155771 DOI: 10.1111/epi.16370] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 12/11/2022]
Abstract
The mechanistic target of rapamycin (mTOR) pathway has been implicated in a growing number of malformations of cortical development (MCD) associated with intractable epilepsy. Mutations in single genes encoding mTOR pathway regulatory proteins have been linked to MCD such as focal cortical dysplasia (FCD) types IIa and IIb, hemimegalencephaly (HME), and megalencephaly. Recent studies have demonstrated that the GATOR1 protein complex, comprised of DEPDC5, NPRL3, and NPRL2, plays a pivotal role in regulating mTOR signaling in response to cellular amino acid levels and that mutations in DEPDC5, NPRL3, or NPRL2 are linked to FCD, HME, and seizures. Histopathological analysis of FCD and HME tissue specimens resected from individuals harboring DEPDC5, NPRL3, or NPRL2 gene mutations reveals hyperactivation of mTOR pathway signaling. Family pedigrees carrying mutations in either DEPDC5 or NPRL3 share clinical phenotypes of epilepsy and MCD, as well as intellectual and neuropsychiatric disabilities. Interestingly, some individuals with seizures associated with DEPDC5, NPRL3, or NPRL2 variants exhibit normal brain imaging suggesting either occult MCD or a role for these genes in non-lesional neocortical epilepsy. Mouse models resulting from knockdown or knockout of either Depdc5 or Nprl3 exhibit altered cortical lamination, neuronal dysmorphogenesis, and enhanced neuronal excitability as reported in models resulting from direct mTOR activation through expression of its canonical activator RHEB. The role of the GATOR1 proteins in regulating mTOR signaling suggest plausible options for mTOR inhibition in the treatment of epilepsy associated with mutations in DEPDC5, NPRL3, or NPRL2.
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Affiliation(s)
- Philip H. Iffland
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Vincent Carson
- The Clinic for Special Children, Strasburg, Pennsylvania
| | - Angelique Bordey
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut
| | - Peter B. Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, Maryland
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Khor ES, Noor SM, Wong PF. Understanding the Role of ztor in Aging-related Diseases Using the Zebrafish Model. In Vivo 2019; 33:1713-1720. [PMID: 31662495 DOI: 10.21873/invivo.11661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 08/15/2019] [Accepted: 08/16/2019] [Indexed: 12/14/2022]
Abstract
The mammalian target of rapamycin (mTOR), a 289 kDa serine/threonine protein kinase of the phosphoinositide 3-kinase (PI3K)-related family is known for its role in regulating lifespan and the aging process in humans and rodents. Aging in zebrafish very much resembles aging in humans. Aged zebrafish often manifest with spinal curvature, cataracts and cognitive frailty, akin to human age-related phenotypical effects such as osteoarthritis, dwindling vision and cognitive dysfunction. However, the role of the zebrafish orthologue of mTOR, ztor, is less defined in these areas. This review paper discusses the tale of growing old in the zebrafish, the physiological roles of ztor in normal developmental processes and its involvement in the pathogenesis of aging-related diseases such as metabolic disorders and cancers.
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Affiliation(s)
- Eng-Soon Khor
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Suzita Mohd Noor
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Pooi-Fong Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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