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Li K, Cao JF, Gong Y, Xiong L, Wu M, Qi Y, Ying X, Liu D, Ma X, Zhang X. Rapamycin improves the survival of epilepsy model cells by blocking phosphorylation of mTOR base on computer simulations and cellular experiments. Neurochem Int 2024; 176:105746. [PMID: 38641027 DOI: 10.1016/j.neuint.2024.105746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/08/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
PURPOSE Epilepsy is a chronic brain dysfunction characterized by recurrent epileptic seizures. Rapamycin is a naturally occurring macrolide from Streptomyces hygroscopicus, and rapamycin may provide a protective effect on the nervous system by affecting mTOR. Therefore, we investigated the pharmacologic mechanism of rapamycin treating epilepsy through bioinformatics analysis, cellular experiments and supercomputer simulation. METHODS Bioinformatics analysis was used to analyze targets of rapamycin treating epilepsy. We established epilepsy cell model by HT22 cells. RT-qPCR, WB and IF were used to verify the effects of rapamycin on mTOR at gene level and protein level. Computer simulations were used to model and evaluate the stability of rapamycin binding to mTOR protein. RESULTS Bioinformatics indicated mTOR played an essential role in signaling pathways of cell growth and cell metabolism. Cellular experiments showed that rapamycin could promote cell survival, and rapamycin did not have an effect on mRNA expression of mTOR. However, rapamycin was able to significantly inhibit the phosphorylation of mTOR at protein level. Computer simulations indicated that rapamycin was involved in the treatment of epilepsy through regulating phosphorylation of mTOR at protein level. CONCLUSION We found that rapamycin was capable of promoting the survival of epilepsy cells by inhibiting the phosphorylation of mTOR at protein level, and rapamycin did not have an effect on mRNA expression of mTOR. In addition to the traditional study that rapamycin affects mTORC1 complex by acting on FKBP12, this study found rapamycin could also directly block the phosphorylation of mTOR, therefore affecting the assembly of mTORC1 complex and mTOR signaling pathway.
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Affiliation(s)
- Kezhou Li
- College of Medicine, Southwest Jiaotong University, Chengdu, China; Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu, China
| | - Jun-Feng Cao
- Chengdu Medical College, Chengdu, China; College of Medicine, Southwest Jiaotong University, Chengdu, China
| | | | - Li Xiong
- Chengdu Medical College, Chengdu, China
| | - Mei Wu
- Chengdu Medical College, Chengdu, China
| | - Yue Qi
- Chengdu Medical College, Chengdu, China
| | | | | | - Xuntai Ma
- Chengdu Medical College, Chengdu, China; The First Affiliated Hospital of Clinical Medical College of Chengdu Medical College, Chengdu, China.
| | - Xiao Zhang
- Chengdu Medical College, Chengdu, China.
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Zhang H, Deng J, Gao Z, Wang Y, Zhao F, Zhao H, Fang F. Clinical phenotype and genotype of NPRL2-related epilepsy: Four cases reports and literature review. Seizure 2024; 116:100-106. [PMID: 37741786 DOI: 10.1016/j.seizure.2023.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 09/01/2023] [Accepted: 09/03/2023] [Indexed: 09/25/2023] Open
Abstract
BACKGROUND NPRL2-related epilepsy, caused by pathogenic germline variants of the NPRL2 gene, is a newly discovered childhood epilepsy linked to enhanced mTORC1 signalling. However, the phenotype and genotype of NPRL2 variants are still poorly understood. Here, we summarize the association between the phenotype and genotype of NPRL2-related epilepsy. METHODS A retrospective analysis was conducted for four Chinese children with epilepsy due to likely pathogenic NPRL2 variants identified through whole-exome sequencing (WES). Previous reports of patients with NPRL2-related epilepsy were reviewed systematically. RESULTS One of our patients presented focal epilepsy involving the central region, which should be distinguished from self-limited epilepsy with centrotemporal spikes (SeLECTS). The four novel likely pathogenic NPRL2 variants consisted of two nonsense variants, one frameshift variant, and one copy number variant (CNV). Bioinformatics analysis revealed the two nonsense variants to be highly conserved and cause alterations in protein structure. Including our four cases, a total of 33 patients with NPRL2-related epilepsy have been identified to date. The most common presentation is focal epilepsy (70%), including sleep-related hypermotor epilepsy (SHE), temporal lobe epilepsy (TLE), and frontal lobe epilepsy (FLE). Infantile epileptic spasms syndrome (IESS) is also a notable feature of NPRL2-related epilepsy. Malformations of cortical development (MCD, 8/20), especially focal cortical dysplasia (FCD, 6/20), are common neuroimaging abnormalities. Two-thirds of the NPRL2 variants reported are loss of function (LoF) (14/21). Among these mutations, c.100C>T (p.Arg34*) and c.314T>C (p.Leu105Pro) have been detected in two families (likely due to a founder effect). CONCLUSION NPRL2-related epilepsy shows high phenotypic and genotypic heterogeneity. Our study expands the genotype spectrum of NPRL2-related epilepsy, and the phenotype of focal epilepsy involving the central region should be clearly distinguished with SeLECTS, with reference value for clinical diagnosis.
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Affiliation(s)
- Hongwei Zhang
- Department of Neurology, Beijing Children's Hospital, National Center for Children's Health, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing 100045, China; Epilepsy Center, Children's Hospital Affiliated to Shandong University, Jinan, China; Epilepsy Center, Jinan Children's Hospital, Jinan, China
| | - Jie Deng
- Department of Neurology, Beijing Children's Hospital, National Center for Children's Health, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing 100045, China
| | - Zaifen Gao
- Epilepsy Center, Children's Hospital Affiliated to Shandong University, Jinan, China; Epilepsy Center, Jinan Children's Hospital, Jinan, China
| | - Yaping Wang
- Epilepsy Center, Children's Hospital Affiliated to Shandong University, Jinan, China; Epilepsy Center, Jinan Children's Hospital, Jinan, China
| | - Fen Zhao
- Epilepsy Center, Children's Hospital Affiliated to Shandong University, Jinan, China; Epilepsy Center, Jinan Children's Hospital, Jinan, China
| | - Hongyang Zhao
- Department of Pediatrics, Central Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Fang Fang
- Department of Neurology, Beijing Children's Hospital, National Center for Children's Health, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing 100045, China.
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Chen Y, Guan W, Wang ML, Lin XY. PI3K-AKT/mTOR Signaling in Psychiatric Disorders: A Valuable Target to Stimulate or Suppress? Int J Neuropsychopharmacol 2024; 27:pyae010. [PMID: 38365306 PMCID: PMC10888523 DOI: 10.1093/ijnp/pyae010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 02/08/2024] [Indexed: 02/18/2024] Open
Abstract
Economic development and increased stress have considerably increased the prevalence of psychiatric disorders in recent years, which rank as some of the most prevalent diseases globally. Several factors, including chronic social stress, genetic inheritance, and autogenous diseases, lead to the development and progression of psychiatric disorders. Clinical treatments for psychiatric disorders include psychotherapy, chemotherapy, and electric shock therapy. Although various achievements have been made researching psychiatric disorders, the pathogenesis of these diseases has not been fully understood yet, and serious adverse effects and resistance to antipsychotics are major obstacles to treating patients with psychiatric disorders. Recent studies have shown that the mammalian target of rapamycin (mTOR) is a central signaling hub that functions in nerve growth, synapse formation, and plasticity. The PI3K-AKT/mTOR pathway is a critical target for mediating the rapid antidepressant effects of these pharmacological agents in clinical and preclinical research. Abnormal PI3K-AKT/mTOR signaling is closely associated with the pathogenesis of several neurodevelopmental disorders. In this review, we focused on the role of mTOR signaling and the related aberrant neurogenesis in psychiatric disorders. Elucidating the neurobiology of the PI3K-AKT/mTOR signaling pathway in psychiatric disorders and its actions in response to antidepressants will help us better understand brain development and quickly identify new therapeutic targets for the treatment of these mental illnesses.
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Affiliation(s)
- Yan Chen
- Department of Neurology, Nantong Third People’s Hospital, Affiliated Nantong Hospital 3 of Nantong University, Nantong, Jiangsu, China
| | - Wei Guan
- Department of Pharmacology, Pharmacy College, Nantong University, Nantong, Jiangsu, China
| | - Mei-Lan Wang
- Department of Neurology, Nantong Third People’s Hospital, Affiliated Nantong Hospital 3 of Nantong University, Nantong, Jiangsu, China
| | - Xiao-Yun Lin
- Department of Neurology, Nantong Third People’s Hospital, Affiliated Nantong Hospital 3 of Nantong University, Nantong, Jiangsu, China
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Cui Y, Zhai Y, Yuan Y, Wang X, Xu Q, Wu X, Xu L, Ren T, Wang Q, Sun H. Inhibition of PTEN-induced kinase 1 autophosphorylation may assist in preventing epileptogenesis induced by pentylenetetrazol. Neurochem Int 2024; 172:105644. [PMID: 38029887 DOI: 10.1016/j.neuint.2023.105644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/15/2023] [Accepted: 11/21/2023] [Indexed: 12/01/2023]
Abstract
PTEN-induced kinase 1 (PINK1) autophosphorylation-triggered mitophagy is the main mitophagic pathway in the nervous system. Moreover, multiple studies have confirmed that mitophagy is closely related to the occurrence and development of epilepsy. Therefore, we speculated that the PINK1 autophosphorylation may be involved in epileptogenesis by mediating mitophagic pathway. This study aimed to explore the contribution of activated PINK1 to epileptogenesis induced by pentylenetetrazol (PTZ) in Sprague‒Dawley rats. During PTZ-induced epileptogenesis, the levels of phosphorylated PINK1 were increased, accompanied by elevated mitophagy, mitochondria oxidative stress and neuronal damage. After microRNA intervention targeting translocase outer mitochondrial membrane 7 (TOM7) or overlapping with the m-AAA protease 1 homolog (OMA1), the levels of PINK1 phosphorylation, mitophagy, mitochondrial oxidative stress, neuronal injury were observed in the rats with induced epileptogenesis. Furthermore, inhibiting of the expression of TOM7, a positive regulator of PINK1 autophosphorylation, reversed the increase in PINK1 phosphorylation and alleviated mitophagy, neuronal injury, thereby preventing epileptogenesis. In contrast, reducing the levels of OMA1, a negative regulator of PINK1 autophosphorylation, led to increased phosphorylation of PINK1, accompanied by aggravated neuronal injury and ultimately, epileptogenesis. This study confirmed the contribution of activated PINK1 to PTZ-induced epileptogenesis and suggested that the inhibition of PINK1 autophosphorylation may assist in preventing epileptogenesis.
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Affiliation(s)
- Yaru Cui
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Yujie Zhai
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Yi Yuan
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Xiaoqian Wang
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Qianqian Xu
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Xiangdong Wu
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Linlin Xu
- Department of Neurology, The Second Hospital of Shandong University, Jinan, 250033, China
| | - Tianpu Ren
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China
| | - Qiaoyun Wang
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China.
| | - Hongliu Sun
- School of Pharmaceutical Sciences, Binzhou Medical University, Yantai, 264003, China.
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Dainelli A, Iacomino M, Rossato S, Bugin S, Traverso M, Severino M, Gustincich S, Capra V, Di Duca M, Zara F, Scala M, Striano P. Refining the electroclinical spectrum of NPRL3-related epilepsy: A novel multiplex family and literature review. Epilepsia Open 2023; 8:1314-1330. [PMID: 37491868 PMCID: PMC10690669 DOI: 10.1002/epi4.12798] [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: 02/20/2023] [Accepted: 07/17/2023] [Indexed: 07/27/2023] Open
Abstract
OBJECTIVE NPRL3-related epilepsy (NRE) is an emerging condition set within the wide GATOR-1 spectrum with a particularly heterogeneous and elusive phenotypic expression. Here, we delineated the genotype-phenotype spectrum of NRE, reporting an illustrative familial case and reviewing pertinent literature. METHODS Through exome sequencing (ES), we investigated a 12-year-old girl with recurrent focal motor seizures during sleep, suggestive of sleep-related hypermotor epilepsy (SHE), and a family history of epilepsy in siblings. Variant segregation analysis was performed by Sanger sequencing. All previously published NRE patients were thoroughly reviewed and their electroclinical features were analyzed and compared with the reported subjects. RESULTS In the proband, ES detected the novel NPRL3 frameshift variant (NM_001077350.3): c.151_152del (p.Thr51Glyfs*5). This variant is predicted to cause a loss of function and segregated in one affected brother. The review of 76 patients from 18 publications revealed the predominance of focal-onset seizures (67/74-90%), with mainly frontal and frontotemporal (32/67-47.7%), unspecified (19/67-28%), or temporal (9/67-13%) onset. Epileptic syndromes included familial focal epilepsy with variable foci (FFEVF) (29/74-39%) and SHE (11/74-14.9%). Fifteen patients out of 60 (25%) underwent epilepsy surgery, 11 of whom achieved complete seizure remission (11/15-73%). Focal cortical dysplasia (FCD) type 2A was the most frequent histopathological finding. SIGNIFICANCE We reported an illustrative NPRL3-related epilepsy (NRE) family with incomplete penetrance. This condition consists of a heterogeneous spectrum of clinical and neuroradiological features. Focal-onset motor seizures are predominant, and almost half of the cases fulfill the criteria for SHE or FFEVF. MRI-negative cases are prevalent, but the association with malformations of cortical developments (MCDs) is significant, especially FCD type 2a. The beneficial impact of epilepsy surgery in patients with MCD-related epilepsy further supports the inclusion of brain MRI in the workup of NRE patients.
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Affiliation(s)
- Alice Dainelli
- Pediatric Neurology and Muscular Diseases UnitIRCCS Istituto Giannina GasliniGenoaItaly
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child HealthUniversità Degli Studi di GenovaGenoaItaly
| | | | - Sara Rossato
- U.O.C. Pediatria, Ospedale San BortoloVicenzaItaly
| | | | - Monica Traverso
- Pediatric Neurology and Muscular Diseases UnitIRCCS Istituto Giannina GasliniGenoaItaly
| | | | | | - Valeria Capra
- UOC Genetica MedicaIRCCS Istituto Giannina GasliniGenoaItaly
| | - Marco Di Duca
- UOC Genetica MedicaIRCCS Istituto Giannina GasliniGenoaItaly
| | - Federico Zara
- UOC Genetica MedicaIRCCS Istituto Giannina GasliniGenoaItaly
| | - Marcello Scala
- Pediatric Neurology and Muscular Diseases UnitIRCCS Istituto Giannina GasliniGenoaItaly
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child HealthUniversità Degli Studi di GenovaGenoaItaly
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases UnitIRCCS Istituto Giannina GasliniGenoaItaly
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child HealthUniversità Degli Studi di GenovaGenoaItaly
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Zhao W, Xie C, Zhang X, Liu J, Liu J, Xia Z. Advances in the mTOR signaling pathway and its inhibitor rapamycin in epilepsy. Brain Behav 2023; 13:e2995. [PMID: 37221133 PMCID: PMC10275542 DOI: 10.1002/brb3.2995] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 03/15/2023] [Accepted: 03/22/2023] [Indexed: 05/25/2023] Open
Abstract
INTRODUCTION Epilepsy is one of the most common and serious brain syndromes and has adverse consequences on a patient's neurobiological, cognitive, psychological, and social wellbeing, thereby threatening their quality of life. Some patients with epilepsy experience poor treatment effects due to the unclear pathophysiological mechanisms of the syndrome. Dysregulation of the mammalian target of the rapamycin (mTOR) pathway is thought to play an important role in the onset and progression of some epilepsies. METHODS This review summarizes the role of the mTOR signaling pathway in the pathogenesis of epilepsy and the prospects for the use of mTOR inhibitors. RESULTS The mTOR pathway functions as a vital mediator in epilepsy development through diverse mechanisms, indicating that the it has great potential as an effective target for epilepsy therapy. The excessive activation of mTOR signaling pathway leads to structural changes in neurons, inhibits autophagy, exacerbates neuron damage, affects mossy fiber sprouting, enhances neuronal excitability, increases neuroinflammation, and is closely associated with tau upregulation in epilepsy. A growing number of studies have demonstrated that mTOR inhibitors exhibit significant antiepileptic effects in both clinical applications and animal models. Specifically, rapamycin, a specific inhibitor of TOR, reduces the intensity and frequency of seizures. Clinical studies in patients with tuberous sclerosis complex have shown that rapamycin has the function of reducing seizures and improving this disease. Everolimus, a chemically modified derivative of rapamycin, has been approved as an added treatment to other antiepileptic medicines. Further explorations are needed to evaluate the therapeutic efficacy and application value of mTOR inhibitors in epilepsy. CONCLUSIONS Targeting the mTOR signaling pathway provides a promising prospect for the treatment of epilepsy.
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Affiliation(s)
- Wei Zhao
- Department of GerontologyThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanChina
| | - Cong Xie
- Department of GerontologyThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanChina
| | - Xu Zhang
- Department of GerontologyThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanChina
| | - Ju Liu
- Laboratory of Microvascular MedicineMedical Research CenterShandong Provincial Qianfoshan Hospital, Shandong UniversityJinanChina
| | - Jinzhi Liu
- Department of GerontologyThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanChina
- Department of NeurologyLiaocheng People's Hospital and Liaocheng Clinical School of Shandong First Medical UniversityLiaochengChina
- Department of GerontologyCheeloo College of MedicineShandong Provincial Qianfoshan Hospital, Shandong UniversityJinanChina
- Department of Geriatric NeurologyThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanChina
| | - Zhangyong Xia
- Department of NeurologyLiaocheng People's Hospital and Liaocheng Clinical School of Shandong First Medical UniversityLiaochengChina
- Department of NeurologyCheeloo College of MedicineLiaocheng People's Hospital, Shandong UniversityJinanChina
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Lafourcade CA, Sparks FT, Bordey A, Wyneken U, Mohammadi MH. Cannabinoid regulation of neurons in the dentate gyrus during epileptogenesis: Role of CB1R-associated proteins and downstream pathways. Epilepsia 2023. [PMID: 36869624 DOI: 10.1111/epi.17569] [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: 10/11/2022] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/05/2023]
Abstract
The hippocampal formation plays a central role in the development of temporal lobe epilepsy (TLE), a disease characterized by recurrent, unprovoked epileptic discharges. TLE is a neurologic disorder characterized by acute long-lasting seizures (i.e., abnormal electrical activity in the brain) or seizures that occur in close proximity without recovery, typically after a brain injury or status epilepticus. After status epilepticus, epileptogenic hyperexcitability develops gradually over the following months to years, resulting in the emergence of chronic, recurrent seizures. Acting as a filter or gate, the hippocampal dentate gyrus (DG) normally prevents excessive excitation from propagating through the hippocampus, and is considered a critical region in the progression of epileptogenesis in pathological conditions. Importantly, lipid-derived endogenous cannabinoids (endocannabinoids), which are produced on demand as retrograde messengers, are central regulators of neuronal activity in the DG circuit. In this review, we summarize recent findings concerning the role of the DG in controlling hyperexcitability and propose how DG regulation by cannabinoids (CBs) could provide avenues for therapeutic interventions. We also highlight possible pathways and manipulations that could be relevant for the control of hyperexcitation. The use of CB compounds to treat epilepsies is controversial, as anecdotal evidence is not always validated by clinical trials. Recent publications shed light on the importance of the DG as a region regulating incoming hippocampal excitability during epileptogenesis. We review recent findings concerning the modulation of the hippocampal DG circuitry by CBs and discuss putative underlying pathways. A better understanding of the mechanisms by which CBs exert their action during seizures may be useful to improve therapies.
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Affiliation(s)
- Carlos A Lafourcade
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, China
| | - Fraser T Sparks
- Department of Neuroscience, Columbia University, New York, New York, USA.,Current: Regeneron Pharmaceuticals, Tarrytown, New York, USA
| | - Angelique Bordey
- Department of Neurosurgery, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ursula Wyneken
- Centro de Investigación e Innovación Biomédica, Laboratorio de Neurociencias, Universidad de Los Andes, Santiago, Chile.,Center of Interventional Medicine for Precision and Advanced Cellular Therapy, Santiago, Chile
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8
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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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Rubio C, López-López F, Rojas-Hernández D, Moreno W, Rodríguez-Quintero P, Rubio-Osornio M. Caloric restriction: Anti-inflammatory and antioxidant mechanisms against epileptic seizures. Epilepsy Res 2022; 186:107012. [PMID: 36027691 DOI: 10.1016/j.eplepsyres.2022.107012] [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: 09/13/2021] [Revised: 01/26/2022] [Accepted: 08/13/2022] [Indexed: 11/03/2022]
Abstract
Caloric restriction (CR) possesses different cellular mechanisms. Though there are still gaps in the literature regarding its plausible beneficial effects, the suggestion that this alternative therapy can improve the inflammatory and antioxidant response to control epileptic seizures is explored throughout this study. Epilepsy is the second most prevalent neurodegenerative disease in the world. However, the appropriate mechanisms for it to be fully controlled are still unknown. Neuroinflammation and oxidative stress promote epileptic seizures' appearance and might even aggravate them. There is growing evidence that caloric restriction has extensive anti-inflammatory and antioxidant properties. For instance, nuclear factor erythroid 2-related factor 2 (Nrf2) and all-trans retinoic acid (ATRA) have been proposed to induce antioxidant processes and ulteriorly improve the disease progression. Caloric restriction can be an option for those patients with refractory epilepsy since it allows for anti-inflammatory and antioxidant properties to evolve within the brain areas involved.
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Affiliation(s)
- Carmen Rubio
- Departamento de Neurofisiología, Instituto Nacional de Neurología y Neurocirugía, Mexico
| | - Felipe López-López
- Departamento de Neurofisiología, Instituto Nacional de Neurología y Neurocirugía, Mexico; Facultad de Medicina, Universidad Autónoma de Baja California, Campus Mexicali, Mexico
| | - Daniel Rojas-Hernández
- Departamento de Neurofisiología, Instituto Nacional de Neurología y Neurocirugía, Mexico; Universidad Autónoma Metropolitana, Unidad Xochimilco, Mexico
| | - Wilhelm Moreno
- Departamento de Neurofisiología, Instituto Nacional de Neurología y Neurocirugía, Mexico; Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico
| | - Paola Rodríguez-Quintero
- Departamento de Neurofisiología, Instituto Nacional de Neurología y Neurocirugía, Mexico; Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico
| | - Moisés Rubio-Osornio
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía, Mexico.
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10
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Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) senses nutrient levels in the cell and based on the availability, regulates cellular growth and proliferation. Its activity is tightly modulated by two GTPase units, the Rag GTPases and the Rheb GTPase. The Rag GTPases are the central hub of amino acid sensing as they summarize the amino acid signals from upstream regulators and control the subcellular localization of mTORC1. Unique from canonical signaling GTPases, the Rag GTPases are obligatory heterodimers, and the two subunits coordinate their nucleotide loading states to regulate their functional states. Robust biochemical analysis is indispensable to understanding the molecular mechanism governing the GTPase cycle. This chapter discusses protocols for purifying and biochemically characterizing the Rag GTPase heterodimer. We described two purification protocols to recombinantly produce the Rag GTPase heterodimer in large quantities. We then described assays to quantitatively measure the nucleotide binding and hydrolysis by the Rag GTPases. These assays allow for a thorough investigation of this unique heterodimeric GTPase, and they could be applicable to investigations of other noncanonical GTPases.
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Affiliation(s)
- Dylan D Doxsey
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Kuang Shen
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, United States.
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11
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Blaine AT, Miao Y, Yuan J, Palant S, Liu RJ, Zhang ZY, van Rijn RM. Exploration of beta-arrestin isoform signaling pathways in delta opioid receptor agonist-induced convulsions. Front Pharmacol 2022; 13:914651. [PMID: 36059958 PMCID: PMC9428791 DOI: 10.3389/fphar.2022.914651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/13/2022] [Indexed: 11/17/2022] Open
Abstract
The δ-opioid receptor (δOR) has been considered as a therapeutic target in multiple neurological and neuropsychiatric disorders particularly as δOR agonists are deemed safer alternatives relative to the more abuse-liable µ-opioid receptor drugs. Clinical development of δOR agonists, however, has been challenging in part due to the seizure-inducing effects of certain δOR agonists. Especially agonists that resemble the δOR-selective agonist SNC80 have well-established convulsive activity. Close inspection suggests that many of those seizurogenic δOR agonists efficaciously recruit β-arrestin, yet surprisingly, SNC80 displays enhanced seizure activity in β-arrestin 1 knockout mice. This finding led us to hypothesize that perhaps β-arrestin 1 is protective against, whereas β-arrestin 2 is detrimental for δOR-agonist-induced seizures. To investigate our hypothesis, we characterized three different δOR agonists (SNC80, ADL5859, ARM390) in cellular assays and in vivo in wild-type and β-arrestin 1 and β-arrestin 2 knockout mice for seizure activity. We also investigated downstream kinases associated with β-arrestin-dependent signal transduction. We discovered that δOR agonist-induced seizure activity strongly and positively correlates with β-arrestin 2 efficacy for the agonist, but that indirect inhibition of ERK activation using the MEK inhibitor SL327 did not inhibit seizure potency and duration. Inhibition of the PI3K/AKT/mTOR signaling with honokiol but not PQR530, attenuated SNC80 seizure duration in β-arrestin 1 knockout, but honokiol did not reduce SNC80-induced seizures in wild-type mice. Ultimately, our results indicate that β-arrestin 2 is correlated with δOR agonist-induced seizure intensity, but that global β-arrestin 1 knockout mice are a poor model system to investigate their mechanism of action.
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Affiliation(s)
- Arryn T. Blaine
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, IN, United States
| | - Yiming Miao
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Jinling Yuan
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Sophia Palant
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Rebecca J. Liu
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Drug Discovery, West Lafayette, IN, United States
- Purdue University Cancer Center, West Lafayette, IN, United States
| | - Richard. M. van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Drug Discovery, West Lafayette, IN, United States
- Purdue University Cancer Center, West Lafayette, IN, United States
- Purdue Institute for Integrative Neuroscience, West Lafayette, IN, United States
- *Correspondence: Richard. M. van Rijn,
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Zoungrana LI, Krause-Hauch M, Wang H, Fatmi MK, Bates L, Li Z, Kulkarni P, Ren D, Li J. The Interaction of mTOR and Nrf2 in Neurogenesis and Its Implication in Neurodegenerative Diseases. Cells 2022; 11:cells11132048. [PMID: 35805130 PMCID: PMC9265429 DOI: 10.3390/cells11132048] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/23/2022] [Accepted: 06/26/2022] [Indexed: 12/24/2022] Open
Abstract
Neurogenesis occurs in the brain during embryonic development and throughout adulthood. Neurogenesis occurs in the hippocampus and under normal conditions and persists in two regions of the brain—the subgranular zone (SGZ) in the dentate gyrus of the hippocampus and the subventricular zone (SVZ) of the lateral ventricles. As the critical role in neurogenesis, the neural stem cells have the capacity to differentiate into various cells and to self-renew. This process is controlled through different methods. The mammalian target of rapamycin (mTOR) controls cellular growth, cell proliferation, apoptosis, and autophagy. The transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) is a major regulator of metabolism, protein quality control, and antioxidative defense, and is linked to neurogenesis. However, dysregulation in neurogenesis, mTOR, and Nrf2 activity have all been associated with neurodegenerative diseases such as Alzheimer’s, Huntington’s, and Parkinson’s. Understanding the role of these complexes in both neurogenesis and neurodegenerative disease could be necessary to develop future therapies. Here, we review both mTOR and Nrf2 complexes, their crosstalk and role in neurogenesis, and their implication in neurodegenerative diseases.
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Affiliation(s)
- Linda Ines Zoungrana
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Meredith Krause-Hauch
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Hao Wang
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Mohammad Kasim Fatmi
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Lauryn Bates
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Zehui Li
- Department of Medical Engineering, College of Engineering and Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (Z.L.); (P.K.)
| | - Parth Kulkarni
- Department of Medical Engineering, College of Engineering and Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (Z.L.); (P.K.)
| | - Di Ren
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
| | - Ji Li
- Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (L.I.Z.); (M.K.-H.); (H.W.); (M.K.F.); (L.B.); (D.R.)
- Correspondence: ; Tel.: +1-813-974-4917
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Daněk J, Danačíková Š, Kala D, Svoboda J, Kapoor S, Pošusta A, Folbergrová J, Tauchmannová K, Mráček T, Otáhal J. Sulforaphane Ameliorates Metabolic Changes Associated With Status Epilepticus in Immature Rats. Front Cell Neurosci 2022; 16:855161. [PMID: 35370554 PMCID: PMC8965559 DOI: 10.3389/fncel.2022.855161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/16/2022] [Indexed: 11/24/2022] Open
Abstract
Status epilepticus (SE) is a common paediatric emergency with the highest incidence in the neonatal period and is a well-known epileptogenic insult. As previously established in various experimental and human studies, SE induces long-term alterations to brain metabolism, alterations that directly contribute to the development of epilepsy. To influence these changes, organic isothiocyanate compound sulforaphane (SFN) has been used in the present study for its known effect of enhancing antioxidative, cytoprotective, and metabolic cellular properties via the Nrf2 pathway. We have explored the effect of SFN in a model of acquired epilepsy induced by Li-Cl pilocarpine in immature rats (12 days old). Energy metabolites PCr, ATP, glucose, glycogen, and lactate were determined by enzymatic fluorimetric methods during the acute phase of SE. Protein expression was evaluated by Western blot (WB) analysis. Neuronal death was scored on the FluoroJadeB stained brain sections harvested 24 h after SE. To assess the effect of SFN on glucose metabolism we have performed a series of 18F-DG μCT/PET recordings 1 h, 1 day, and 3 weeks after the induction of SE. Responses of cerebral blood flow (CBF) to electrical stimulation and their influence by SFN were evaluated by laser Doppler flowmetry (LDF). We have demonstrated that the Nrf2 pathway is upregulated in the CNS of immature rats after SFN treatment. In the animals that had undergone SE, SFN was responsible for lowering glucose uptake in most regions 1 h after the induction of SE. Moreover, SFN partially reversed hypometabolism observed after 24 h and achieved full reversal at approximately 3 weeks after SE. Since no difference in cell death was observed in SFN treated group, these changes cannot be attributed to differences in neurodegeneration. SFN per se did not affect the glucose uptake at any given time point suggesting that SFN improves endogenous CNS ability to adapt to the epileptogenic insult. Furthermore, we had discovered that SFN improves blood flow and accelerates CBF response to electrical stimulation. Our findings suggest that SFN improves metabolic changes induced by SE which have been identified during epileptogenesis in various animal models of acquired epilepsy.
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Affiliation(s)
- Jan Daněk
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Šárka Danačíková
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - David Kala
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jan Svoboda
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
- Department of Pathophysiology, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Sonam Kapoor
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Antonín Pošusta
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | | | | | - Tomáš Mráček
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jakub Otáhal
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
- Department of Pathophysiology, Second Faculty of Medicine, Charles University, Prague, Czechia
- *Correspondence: Jakub Otáhal,
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Zhang J, Shen Y, Yang Z, Yang F, Li Y, Yu B, Chen W, Gan J. A splicing variation in NPRL2 causing familial focal epilepsy with variable foci: additional cases and literature review. J Hum Genet 2022; 67:79-85. [PMID: 34376795 PMCID: PMC8786660 DOI: 10.1038/s10038-021-00969-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 01/31/2023]
Abstract
NPRL2 (nitrogen permease regulator like 2) is a component of the GATOR1(GAP activity towards rags complex 1) proteins, which is an inhibitor of the amino acid-sensing branch of the mTORC1 pathway. GATOR1 complex variations were reported to correlate with familial focal epilepsy with variable foci (FFEVF). However, FFEVF caused by NPRL2 variants has not been widely explored. Here, we describe a variant, 339+2T>C, in NPRL2 identified by trio whole-exome sequencing (WES) in a family. This splicing variant that occurred at the 5' end of exon 3 was confirmed by minigene assays, which affected alternative splicing and led to exon 3 skipping in NPRL2. Our cases presented multiple seizure types (febrile seizures, infantile spasms, focal seizures, or focal to generalized tonic-clonic seizures). Electroencephalogram (EEG) showed frequent discharges in the left frontal and central regions. A favorable prognosis was achieved in response to vitamin B6 and topiramate when the patient was seven months old. Our study expands the phenotype and genotype spectrum of FFEVF and provides solid diagnostic evidence for FFEVF.
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Affiliation(s)
- Jia Zhang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of the Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | - Yajun Shen
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of the Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | | | | | - Yang Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of the Ministry of Education, Sichuan University, Chengdu, Sichuan, China
| | - Bo Yu
- Department of Pediatrics, The City Central Hospital of Wanyuan, Wanyuan, Sichuan, China
| | - Wanlin Chen
- Department of Pediatrics, The City Central Hospital of Wanyuan, Wanyuan, Sichuan, China
| | - Jing Gan
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.
- Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of the Ministry of Education, Sichuan University, Chengdu, Sichuan, China.
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15
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Ko A, Sim NS, Choi HS, Yang D, Kim SH, Lee JS, Kim DS, Lee JH, Kim HD, Kang HC. Efficacy of the Ketogenic Diet for Pediatric Epilepsy According to the Presence of Detectable Somatic mTOR Pathway Mutations in the Brain. J Clin Neurol 2022; 18:71-78. [PMID: 35021279 PMCID: PMC8762511 DOI: 10.3988/jcn.2022.18.1.71] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 11/23/2022] Open
Abstract
Background and Purpose A multifactorial antiepileptic mechanism underlies the ketogenic diet (KD), and one of the proposed mechanisms of action is that the KD inhibits the mammalian target of rapamycin (mTOR) pathway. To test this clinically, this study aimed to determine the efficacy of the KD in patients with pathologically confirmed focal cortical dysplasia (FCD) due to genetically identifiable mTOR pathway dysregulation. Methods A cohort of patients with pathologically confirmed FCD after epilepsy surgery and who were screened for the presence of germline and somatic mutations related to the mTOR pathway in peripheral blood and resected brain tissue was constructed prospectively. A retrospective review of the efficacy of the prior KD in these patients was performed. Results Twenty-five patients with pathologically confirmed FCD and who were screened for the presence of detectable somatic mTOR pathway mutations had received a sufficient KD. Twelve of these patients (48.0%) had germline or somatic detectable mTOR pathway mutations. A response was defined as a ≥50% reduction in seizure frequency. The efficacy of the KD after 3 months of dietary therapy was superior in patients with detectable mTOR pathway mutations than in patients without detectable mTOR pathway mutations, although the difference was not statistically significant (responder rates of 58.3% vs. 38.5%, p=0.434). Conclusions A greater proportion of patients with mTOR pathway responded to the KD, but there was no statistically significant difference in efficacy of the KD between patients with and without detectable mTOR pathway mutations. Further study is warranted due to the smallness of the sample and the limited number of mTOR pathway genes tested in this study.
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Affiliation(s)
- Ara Ko
- Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Korea
| | - Nam Suk Sim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Han Som Choi
- Department of Pediatrics, Ewha Womans University Seoul Hospital, Ewha Womans University School of Medicine, Seoul, Korea.,Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Donghwa Yang
- Department of Pediatrics, National Health Insurance Service Ilsan Hospital, Goyang, Korea
| | - Se Hee Kim
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Soo Lee
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Dong Seok Kim
- Department of Neurosurgery, Pediatric Neurosurgery, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Jeong Ho Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Heung Dong Kim
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
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16
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Boada CM, Grossman SN, Grzeskowiak CL, Dumanis S, French JA. Proceedings of the 2020 Epilepsy Foundation Pipeline Conference: Emerging Drugs and Devices. Epilepsy Behav 2021; 125:108364. [PMID: 34731723 DOI: 10.1016/j.yebeh.2021.108364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 09/25/2021] [Indexed: 11/17/2022]
Abstract
From August 27-28, 2020 the Epilepsy Foundation hosted the Pipeline Conference, exploring emerging issues related to antiepileptic drug and device development. The conference featured epilepsy therapeutic companies and academic laboratories developing drugs for focal epilepsies, innovations for rare and ultra-rare diseases, and devices both in clinical trials and approved for use. In this paper, we outline the virtual presentations by the authors, including novel data from their development pipeline.
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Affiliation(s)
- Christina M Boada
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA.
| | - Scott N Grossman
- Department of Neurology, New York University Langone Health, New York, NY, USA
| | | | | | - Jacqueline A French
- Department of Neurology, New York University Langone Health, New York, NY, USA
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An insight into crosstalk among multiple signaling pathways contributing to epileptogenesis. Eur J Pharmacol 2021; 910:174469. [PMID: 34478688 DOI: 10.1016/j.ejphar.2021.174469] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/16/2021] [Accepted: 08/30/2021] [Indexed: 01/04/2023]
Abstract
Despite the years of research, epilepsy remains uncontrolled in one-third of afflicted individuals and poses a health and economic burden on society. Currently available anti-epileptic drugs mainly target the excitatory-inhibitory imbalance despite targeting the underlying pathophysiology of the disease. Recent research focuses on understanding the pathophysiologic mechanisms that lead to seizure generation and on possible new treatment avenues for preventing epilepsy after a brain injury. Various signaling pathways, including the mechanistic target of rapamycin (mTOR) pathway, mitogen-activated protein kinase (MAP-ERK) pathway, JAK-STAT pathway, wnt/β-catenin signaling, cAMP pathway, and jun kinase pathway, have been suggested to play an essential role in this regard. Recent work suggests that the mTOR pathway intervenes epileptogenesis and proposes that mTOR inhibitors may have antiepileptogenic properties for epilepsy. In the same way, several animal studies have indicated the involvement of the Wnt signaling pathway in neurogenesis and neuronal death induced by seizures in different phases (acute and chronic) of seizure development. Various studies have also documented the activation of JAK-STAT signaling in epilepsy and cAMP involvement in epileptogenesis through CREB (cAMP response element-binding protein). Although studies are there, the mechanism for how components of these pathways mediate epileptogenesis requires further investigation. This review summarises the current role of various signaling pathways involved in epileptogenesis and the crosstalk among them. Furthermore, we will also discuss the mechanical base for the interaction between these pathways and how these interactions could be a new emerging promising target for future epilepsy therapies.
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18
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Zhang M, Li B, Liu Y, Tang R, Lang Y, Huang Q, He J. Different Modes of Low-Frequency Focused Ultrasound-Mediated Attenuation of Epilepsy Based on the Topological Theory. MICROMACHINES 2021; 12:mi12081001. [PMID: 34442623 PMCID: PMC8399944 DOI: 10.3390/mi12081001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/19/2021] [Accepted: 08/19/2021] [Indexed: 01/17/2023]
Abstract
Epilepsy is common brain dysfunction, where abnormal synchronized activities can be observed across multiple brain regions. Low-frequency focused pulsed ultrasound has been proven to modulate the epileptic brain network. In this study, we used two modes of low-intensity focused ultrasound (pulsed-wave and continuous-wave) to sonicate the brains of KA-induced epileptic rats, analyzed the EEG functional brain connections to explore their respective effect on the epileptic brain network, and discuss the mechanism of ultrasound neuromodulation. By comparing the brain network characteristics before and after sonication, we found that two modes of ultrasound both significantly affected the functional brain network, especially in the low-frequency band below 12 Hz. After two modes of sonication, the power spectral density of the EEG signals and the connection strength of the brain network were significantly reduced, but there was no significant difference between the two modes. Our results indicated that the ultrasound neuromodulation could effectively regulate the epileptic brain connections. The ultrasound-mediated attenuation of epilepsy was independent of modes of ultrasound.
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Affiliation(s)
- Minjian Zhang
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China; (M.Z.); (B.L.); (Y.L.); (Q.H.)
| | - Bo Li
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China; (M.Z.); (B.L.); (Y.L.); (Q.H.)
| | - Yafei Liu
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China; (M.Z.); (B.L.); (Y.L.); (Q.H.)
| | - Rongyu Tang
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing 100081, China; (R.T.); (Y.L.)
| | - Yiran Lang
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing 100081, China; (R.T.); (Y.L.)
| | - Qiang Huang
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China; (M.Z.); (B.L.); (Y.L.); (Q.H.)
| | - Jiping He
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China; (M.Z.); (B.L.); (Y.L.); (Q.H.)
- Correspondence: ; Tel.: +86-010-68917396
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A Warburg-like metabolic program coordinates Wnt, AMPK, and mTOR signaling pathways in epileptogenesis. PLoS One 2021; 16:e0252282. [PMID: 34358226 PMCID: PMC8345866 DOI: 10.1371/journal.pone.0252282] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 05/12/2021] [Indexed: 02/06/2023] Open
Abstract
Epilepsy is a complex neurological condition characterized by repeated spontaneous seizures and can be induced by initiating seizures known as status epilepticus (SE). Elaborating the critical molecular mechanisms following SE are central to understanding the establishment of chronic seizures. Here, we identify a transient program of molecular and metabolic signaling in the early epileptogenic period, centered on day five following SE in the pre-clinical kainate or pilocarpine models of temporal lobe epilepsy. Our work now elaborates a new molecular mechanism centered around Wnt signaling and a growing network comprised of metabolic reprogramming and mTOR activation. Biochemical, metabolomic, confocal microscopy and mouse genetics experiments all demonstrate coordinated activation of Wnt signaling, predominantly in neurons, and the ensuing induction of an overall aerobic glycolysis (Warburg-like phenomenon) and an altered TCA cycle in early epileptogenesis. A centerpiece of the mechanism is the regulation of pyruvate dehydrogenase (PDH) through its kinase and Wnt target genes PDK4. Intriguingly, PDH is a central gene in certain genetic epilepsies, underscoring the relevance of our elaborated mechanisms. While sharing some features with cancers, the Warburg-like metabolism in early epileptogenesis is uniquely split between neurons and astrocytes to achieve an overall novel metabolic reprogramming. This split Warburg metabolic reprogramming triggers an inhibition of AMPK and subsequent activation of mTOR, which is a signature event of epileptogenesis. Interrogation of the mechanism with the metabolic inhibitor 2-deoxyglucose surprisingly demonstrated that Wnt signaling and the resulting metabolic reprogramming lies upstream of mTOR activation in epileptogenesis. To augment the pre-clinical pilocarpine and kainate models, aspects of the proposed mechanisms were also investigated and correlated in a genetic model of constitutive Wnt signaling (deletion of the transcriptional repressor and Wnt pathway inhibitor HBP1). The results from the HBP1-/- mice provide a genetic evidence that Wnt signaling may set the threshold of acquired seizure susceptibility with a similar molecular framework. Using biochemistry and genetics, this paper outlines a new molecular framework of early epileptogenesis and advances a potential molecular platform for refining therapeutic strategies in attenuating recurrent seizures.
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Abstract
The presence of unprovoked, recurrent seizures, particularly when drug resistant and associated with cognitive and behavioral deficits, warrants investigation for an underlying genetic cause. This article provides an overview of the major classes of genes associated with epilepsy phenotypes divided into functional categories along with the recommended work-up and therapeutic considerations. Gene discovery in epilepsy supports counseling and anticipatory guidance but also opens the door for precision medicine guiding therapy with a focus on those with disease-modifying effects.
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Affiliation(s)
- Luis A Martinez
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund Drive, Houston, TX 77030, USA
| | - Yi-Chen Lai
- Department of Pediatrics, Section of Pediatric Critical Care Medicine, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund Drive, Houston, TX 77030, USA
| | - J Lloyd Holder
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund Drive, Houston, TX 77030, USA
| | - Anne E Anderson
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, 1250 Moursund Drive, Houston, TX 77030, USA.
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21
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Rapamycin alleviates memory deficit against pentylenetetrazole-induced neural toxicity in Wistar male rats. Mol Biol Rep 2021; 48:5083-5091. [PMID: 34165769 DOI: 10.1007/s11033-021-06504-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/17/2021] [Indexed: 10/21/2022]
Abstract
Numerous studies have reported that epilepsy causes memory deficits. The present study was aimed at studying the effect of rapamycin against the memory deficiency of the pentylenetetrazole (PTZ)-kindled animal model of epilepsy. In the present experiment, we randomly chose thirty male rats from the species of Wistar and categorized them in groups of control and experiment (6 for each group). The groups of experiment received the injection of rapamycin (0.5, 1 and 2 mg/kg) intraperitoneally (i.p.) and the group of control received normal saline (0.9%) treatment. Through the PTZ's sub-threshold dose (35 mg kg-1, i.p.), all groups were kindled 12 times. Passive avoidance test (PAT) was used for gauging the memory function and the seizure behaviors after the kindling procedure. The rodents were sacrificed at the end of the trial and their brains were scooped for measuring the expression of Gabra1 and Pras40 genes. Statistical analysis unveiled that rapamycin delayed the kindling development and the onset of seizures which are tonic-clonic. Moreover, the administration of rapamycin significantly prevented memory dysfunction in epileptic rats. Finally, it was shown that rapamycin resulted in an increase in the expression levels of Gabra1 and Pras40 genes at the brain tissues. The current research design indicated that rapamycin has beneficial effects for the prevention of memory impairment against PTZ-kindling epilepsy in rats. Such promising outcomes could be attributed to its impact on the Gabra1 and Pras40 genes.
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22
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Huang XY, Hu QP, Shi HY, Zheng YY, Hu RR, Guo Q. Everolimus inhibits PI3K/Akt/mTOR and NF-kB/IL-6 signaling and protects seizure-induced brain injury in rats. J Chem Neuroanat 2021; 114:101960. [PMID: 33915267 DOI: 10.1016/j.jchemneu.2021.101960] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/09/2021] [Accepted: 04/13/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Epilepsy is a common chronic neurological disease caused by the over-synchronization of neurons leading to brain dysfunction. Recurrent seizures can lead to cognitive and behavioral deficits, and irreversible brain damage. While the PI3K/Akt/mTOR pathway regulates various physiological processes of neurons and glia, it may also lead to abnormal neuronal signal transduction under pathological conditions, including that of epilepsy. Everolimus (Eve), an mTOR inhibitor, may modulate neuronal excitability and therefore exert protection against epilepsy. Therefore, this study aimed to investigate the neuroprotective effect of Everolimus on seizure-induced brain injury and its regulation of the PI3K/Akt/mTOR and NF-kB/IL-6 signaling pathway. Kainic acid (KA) 15 mg/kg was used to induce seizures and Everolimus (1, 2, 5 mg/kg) was administered as a pretreatment. Hippocampal tissue was extracted 24 h post-seizure. RESULTS The protein and mRNA expression levels of PI3K、p-AKt、p-mTOR、NF-kB and IL-6 as well as neuronal apoptosis and microglia activation, significantly increased after KA-induced seizures, however, these effects were inhibited by Everolimus treatment. Furthermore, pretreatment with Everolimus decreased seizure scores and increased seizure latency. CONCLUSIONS Everolimus can decrease the PI3K/Akt/mTOR and NF-kB/IL-6 signaling pathway, reduce neuronal apoptosis and microglia activation, and attenuate seizure susceptibility and intensity, thus having a protective effect on seizure-induced brain damage.
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Affiliation(s)
- Xiang-Yi Huang
- Department of Function Examination, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China.
| | - Qing-Peng Hu
- Department of Pediatrics, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China.
| | - Hong-Yun Shi
- Department of Pediatrics, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China
| | - Ya-Yu Zheng
- Department of Pediatrics, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China
| | - Rong-Rong Hu
- Department of Pediatrics, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China
| | - Qian Guo
- Department of Pediatrics, The Second Hospital, University of South China, Hengyang, Hunan, 421001, China
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Hodges SL, Womble PD, Kwok EM, Darner AM, Senger SS, Binder MS, Faust AM, Condon SM, Nolan SO, Quintero SI, Lugo JN. Rapamycin, but not minocycline, significantly alters ultrasonic vocalization behavior in C57BL/6J pups in a flurothyl seizure model. Behav Brain Res 2021; 410:113317. [PMID: 33910029 DOI: 10.1016/j.bbr.2021.113317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/24/2021] [Accepted: 04/21/2021] [Indexed: 12/11/2022]
Abstract
Epilepsy is one of the most common neurological disorders, with individuals having an increased susceptibility of seizures in the first few years of life, making children at risk of developing a multitude of cognitive and behavioral comorbidities throughout development. The present study examined the role of PI3K/Akt/mTOR pathway activity and neuroinflammatory signaling in the development of autistic-like behavior following seizures in the neonatal period. Male and female C57BL/6J mice were administered 3 flurothyl seizures on postnatal (PD) 10, followed by administration of minocycline, the mTOR inhibitor rapamycin, or a combined treatment of both therapeutics. On PD12, isolation-induced ultrasonic vocalizations (USVs) of mice were examined to determine the impact of seizures and treatment on communicative behaviors, a component of the autistic-like phenotype. Seizures on PD10 increased the quantity of USVs in female mice and reduced the amount of complex call types emitted in males compared to controls. Inhibition of mTOR with rapamycin significantly reduced the quantity and duration of USVs in both sexes. Changes in USVs were associated with increases in mTOR and astrocyte levels in male mice, however, three PD10 seizures did not result in enhanced proinflammatory cytokine expression in either sex. Beyond inhibition of mTOR activity by rapamycin, both therapeutics did not demonstrate beneficial effects. These findings emphasize the importance of differences that may exist across preclinical seizure models, as three flurothyl seizures did not induce as drastic of changes in mTOR activity or inflammation as observed in other rodent models.
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Affiliation(s)
- Samantha L Hodges
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA.
| | - Paige D Womble
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Eliesse M Kwok
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Alyssa M Darner
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Savannah S Senger
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Matthew S Binder
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Amanda M Faust
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Siena M Condon
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Suzanne O Nolan
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Saul I Quintero
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA
| | - Joaquin N Lugo
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA; Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA; Department of Biology, Baylor University, Waco, TX, 76798, USA
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24
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El-Sayed SS, El-Yamany MF, Salem HA, El-Sahar AE. New insights into the effects of vinpocetine against neurobehavioral comorbidities in a rat model of temporal lobe epilepsy via the downregulation of the hippocampal PI3K/mTOR signalling pathway. J Pharm Pharmacol 2021; 73:626-640. [PMID: 33772295 DOI: 10.1093/jpp/rgab011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 01/15/2021] [Indexed: 12/17/2022]
Abstract
OBJECTIVES As one of the most frequent worldwide neurological disorders, epilepsy is an alteration of the central nervous system (CNS) characterized by abnormal increases in neuronal electrical activity. The mammalian target of rapamycin (mTOR) signalling pathway has been investigated as an interesting objective in epilepsy research. Vinpocetine (VNP), a synthesized derivative of the apovincamine alkaloid, has been used in different cerebrovascular disorders. This study aimed to examine the modulatory effects of VNP on neurobehavioral comorbidities via the mTOR signalling pathway in a lithium-pilocarpine (Li-Pil) rat model of seizures. METHODS In male Wistar rats, seizures were induced with a single administration of pilocarpine (60 mg/kg; i.p.) 20 hours after the delivery of a single dose of lithium (3 mEq/kg; i.p.). VNP (10 mg/kg; i.p.) was administered daily for 14 consecutive days before Li-Pil administration. KEY FINDINGS VNP had a protective effect against Li-Pil-induced seizures. VNP improved both the locomotor and cognitive abilities, moreover, VNP exerted a neuroprotective action, as verified histologically and by its inhibitory effects on hippocampal glutamate excitotoxicity, mTOR pathway, and inflammatory and apoptotic parameters. CONCLUSIONS VNP is a valuable candidate for epilepsy therapy via its modulation of the mechanisms underlying epileptogenesis with emphasis on its modulatory effect on mTOR signalling pathway.
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Affiliation(s)
- Sarah S El-Sayed
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El Aini St, Cairo, Egypt
| | - Mohammed F El-Yamany
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El Aini St, Cairo, Egypt
| | - Hesham A Salem
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El Aini St, Cairo, Egypt
| | - Ayman E El-Sahar
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Kasr El Aini St, Cairo, Egypt
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25
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Goldstein HE, Hauptman JS. The Putative Role of mTOR Inhibitors in Non-tuberous Sclerosis Complex-Related Epilepsy. Front Neurol 2021; 12:639319. [PMID: 33643212 PMCID: PMC7907183 DOI: 10.3389/fneur.2021.639319] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 01/25/2021] [Indexed: 11/13/2022] Open
Abstract
Epilepsy affects ~5 out of every 10,000 children per year. Up to one-third of these children have medically refractory epilepsy, with limited to no options for improved seizure control. mTOR, a ubiquitous 289 kDa serine/threonine kinase in the phosphatidylinositol 3-kinase (PI3K)-related kinases (PIKK) family, is dysregulated in a number of human diseases, including tuberous sclerosis complex (TSC) and epilepsy. In cell models of epilepsy and TSC, rapamycin, an mTOR inhibitor, has been shown to decrease seizure frequency and duration, and positively affect cell growth and morphology. Rapamycin has also been shown to prevent or improve epilepsy and prolong survival in animal models of TSC. To date, clinical studies looking at the effects of mTOR inhibitors on the reduction of seizures have mainly focused on patients with TSC. Everolimus (Novartis Pharmaceuticals), a chemically modified rapamycin derivative, has been shown to reduce seizure frequency with reasonable safety and tolerability. Mutations in mTOR or the mTOR pathway have been found in hemimegalencephaly (HME) and focal cortical dysplasias (FCDs), both of which are highly correlated with medically refractory epilepsy. Given the evidence to date, a logical next step is to investigate the role of mTOR inhibitors in the treatment of children with medically refractory non-TSC epilepsy, particularly those children who have also failed resective surgery.
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Affiliation(s)
- Hannah E Goldstein
- Department of Neurological Surgery, University of Washington, Seattle, WA, United States.,Department of Neurosurgery, Seattle Children's Hospital, Seattle, WA, United States
| | - Jason S Hauptman
- Department of Neurological Surgery, University of Washington, Seattle, WA, United States.,Department of Neurosurgery, Seattle Children's Hospital, Seattle, WA, United States
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26
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Singh S, Singh TG, Rehni AK. An Insight into Molecular Mechanisms and Novel Therapeutic Approaches in Epileptogenesis. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2021; 19:750-779. [PMID: 32914725 DOI: 10.2174/1871527319666200910153827] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/22/2022]
Abstract
Epilepsy is the second most common neurological disease with abnormal neural activity involving the activation of various intracellular signalling transduction mechanisms. The molecular and system biology mechanisms responsible for epileptogenesis are not well defined or understood. Neuroinflammation, neurodegeneration and Epigenetic modification elicit epileptogenesis. The excessive neuronal activities in the brain are associated with neurochemical changes underlying the deleterious consequences of excitotoxicity. The prolonged repetitive excessive neuronal activities extended to brain tissue injury by the activation of microglia regulating abnormal neuroglia remodelling and monocyte infiltration in response to brain lesions inducing axonal sprouting contributing to neurodegeneration. The alteration of various downstream transduction pathways resulted in intracellular stress responses associating endoplasmic reticulum, mitochondrial and lysosomal dysfunction, activation of nucleases, proteases mediated neuronal death. The recently novel pharmacological agents modulate various receptors like mTOR, COX-2, TRK, JAK-STAT, epigenetic modulators and neurosteroids are used for attenuation of epileptogenesis. Whereas the various molecular changes like the mutation of the cell surface, nuclear receptor and ion channels focusing on repetitive episodic seizures have been explored by preclinical and clinical studies. Despite effective pharmacotherapy for epilepsy, the inadequate understanding of precise mechanisms, drug resistance and therapeutic failure are the current fundamental problems in epilepsy. Therefore, the novel pharmacological approaches evaluated for efficacy on experimental models of epilepsy need to be identified and validated. In addition, we need to understand the downstream signalling pathways of new targets for the treatment of epilepsy. This review emphasizes on the current state of novel molecular targets as therapeutic approaches and future directions for the management of epileptogenesis. Novel pharmacological approaches and clinical exploration are essential to make new frontiers in curing epilepsy.
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Affiliation(s)
- Shareen Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | | | - Ashish Kumar Rehni
- Cerebral Vascular Disease Research Laboratories, Department of Neurology and Neuroscience Program, University of Miami School of Medicine, Miami, Florida 33101, United States
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Micronized Resveratrol Shows Anticonvulsant Properties in Pentylenetetrazole-Induced Seizure Model in Adult Zebrafish. Neurochem Res 2020; 46:241-251. [PMID: 33108629 DOI: 10.1007/s11064-020-03158-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/16/2020] [Accepted: 10/21/2020] [Indexed: 01/27/2023]
Abstract
Epilepsy affects 50 million people around the world, and the patients experience cognitive, psychological and social consequences. Despite the considerable quantity of antiepileptic drugs available, 30% of patients still suffer in seizure. Therefore, the advance in therapeutic alternatives is mandatory. Resveratrol has been attracting the attention of many researchers because of its pharmacological potential. However, despite its neuroprotective and anti-epileptic effects, clinical resveratrol use is impaired by its low bioavailability. Here, we applied the supercritical fluid micronization technology (SEDS) to overcome this deficit, and investigated the anticonvulsant potential of micronized resveratrol in a PTZ-induced seizure model in adult zebrafish (Danio rerio). SEDS permits obtaining significantly reduced particle size with a fine size distribution in comparison with the starting material. It can improve the pharmacotherapeutic efficacy. Our data showed that micronized resveratrol decreased the occurrence of the tonic-clonic seizure stage and slowed the development of the seizures in a similar manner of diazepam. Non-processed resveratrol was not able to protect the animals. Furthermore, diazepam decreased the locomotion and exploratory behavior. Differently from diazepam, the micronized resveratrol did not induce behavioral adverse events. In addition, our data showed that the PTZ-induced seizures increased the c-fos transcript levels following the neural excitability. However, the increase in c-fos levels was prevented by micronized resveratrol. In conclusion, our results demonstrate that the micronized resveratrol shows anticonvulsant effect, like the classical antiepileptic drug diazepam in a PTZ-induced seizure model. Excitingly, different from diazepam, micronized resveratrol did not provoke behavioral adverse events.
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Microglial mTOR is Neuronal Protective and Antiepileptogenic in the Pilocarpine Model of Temporal Lobe Epilepsy. J Neurosci 2020; 40:7593-7608. [PMID: 32868461 DOI: 10.1523/jneurosci.2754-19.2020] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 08/05/2020] [Accepted: 08/24/2020] [Indexed: 01/01/2023] Open
Abstract
Excessive activation of mammalian target of rapamycin (mTOR) signaling is epileptogenic in genetic epilepsy. However, the exact role of microglial mTOR in acquired epilepsy remains to be clarified. In the present study, we found that mTOR is strongly activated in microglia following excitatory injury elicited by status epilepticus. To determine the role of microglial mTOR signaling in excitatory injury and epileptogenesis, we generated mice with restrictive deletion of mTOR in microglia. Both male and female mice were used in the present study. We found that mTOR-deficient microglia lost their typical proliferative and inflammatory responses to excitatory injury, whereas the proliferation of astrocytes was preserved. In addition, mTOR-deficient microglia did not effectively engulf injured/dying neurons. More importantly, microglial mTOR-deficient mice displayed increased neuronal loss and developed more severe spontaneous seizures. These findings suggest that microglial mTOR plays a protective role in mitigating neuronal loss and attenuating epileptogenesis in the excitatory injury model of epilepsy.SIGNIFICANCE STATEMENT The mammalian target of rapamycin (mTOR) pathway is strongly implicated in epilepsy. However, the effect of mTOR inhibitors in preclinical models of acquired epilepsy is inconsistent. The broad presence of mTOR signaling in various brain cells could prevent mTOR inhibitors from achieving a net therapeutic effect. This conundrum has spurred further investigation of the cell type-specific effects of mTOR signaling in the CNS. We found that activation of microglial mTOR is antiepileptogenic. Thus, microglial mTOR activation represents a novel antiepileptogenic route that appears to parallel the proepileptogenic route of neuronal mTOR activation. This may explain why the net effect of mTOR inhibitors is paradoxical in the acquired models of epilepsy. Our findings could better guide the use of mTOR inhibitors in preventing acquired epilepsy.
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29
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Pavone P, Polizzi A, Marino SD, Corsello G, Falsaperla R, Marino S, Ruggieri M. West syndrome: a comprehensive review. Neurol Sci 2020; 41:3547-3562. [PMID: 32827285 PMCID: PMC7655587 DOI: 10.1007/s10072-020-04600-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 07/14/2020] [Indexed: 12/20/2022]
Abstract
Since its first clinical description (on his son) by William James West (1793–1848) in 1841, and the definition of the classical triad of (1) infantile spasms; (2) hypsarrhythmia, and (3) developmental arrest or regression as “West syndrome”, new and relevant advances have been recorded in this uncommon disorder. New approaches include terminology of clinical spasms (e.g., infantile (IS) vs. epileptic spasms (ES)), variety of clinical and electroencephalographic (EEG) features (e.g., typical ictal phenomena without EEG abnormalities), burden of developmental delay, spectrum of associated genetic abnormalities, pathogenesis, treatment options, and related outcome and prognosis. Aside the classical manifestations, IS or ES may present with atypical electroclinical phenotypes (e.g., subtle spasms; modified hypsarrhythmia) and may have their onset outside infancy. An increasing number of genes, proteins, and signaling pathways play crucial roles in the pathogenesis. This condition is currently regarded as a spectrum of disorders: the so-called infantile spasm syndrome (ISs), in association with other causal factors, including structural, infectious, metabolic, syndromic, and immunologic events, all acting on a genetic predisposing background. Hormonal therapy and ketogenic diet are widely used also in combination with (classical and recent) pharmacological drugs. Biologically targeted and gene therapies are increasingly studied. The present narrative review searched in seven electronic databases (primary MeSH terms/keywords included West syndrome, infantile spasms and infantile spasms syndrome and were coupled to 25 secondary clinical, EEG, therapeutic, outcomes, and associated conditions terms) including MEDLINE, Embase, Cochrane Central, Web of Sciences, Pubmed, Scopus, and OMIM to highlight the past knowledge and more recent advances.
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Affiliation(s)
- Piero Pavone
- Unit of Clinical Pediatrics, AOU "Policlinico", PO "G. Rodolico", University of Catania, Catania, Italy
| | - Agata Polizzi
- Chair of Pediatrics, Department of Educational Sciences, University of Catania, Catania, Italy
| | - Simona Domenica Marino
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", University of Catania, Catania, Italy
| | - Giovanni Corsello
- Unit of Pediatrics and Neonatal Intensive Therapy, Department of Promotion of Maternal and Infantile and Internal Medicine Health, and Specialist Excellence "G. D'Alessandro", University of Palermo, Palermo, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Neonatal Intensive Therapy, Department of Promotion of Maternal and Infantile and Internal Medicine Health, and Specialist Excellence "G. D'Alessandro", University of Palermo, Palermo, Italy
| | - Silvia Marino
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", 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, AOU "Policlinico", PO "G. Rodolico", Via S. Sofia, 87, 95128, Catania, Italy.
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30
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Youn SE, Park S, Kim SH, Lee JS, Kim HD, Kang HC. Long-term outcomes of ketogenic diet in patients with tuberous sclerosis complex-derived epilepsy. Epilepsy Res 2020; 164:106348. [PMID: 32413817 DOI: 10.1016/j.eplepsyres.2020.106348] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 04/10/2020] [Accepted: 04/25/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVE For epilepsy with tuberous sclerosis complex (TSC), ketogenic diet (KD) therapy has been consistently reported to be more beneficial than the average KD therapy response. Herein, we aimed to investigate the long-term outcomes of a KD on patients with TSC and intractable epilepsy. METHODS This study included 31 patients with intractable epilepsy and TSC who were treated with the KD, and an intention-to-treat analysis was performed. RESULTS Overall, 21 of the 31 patients (67.7%) had >50% reduction in seizures at 3 months after initiating the KD. Thirteen of the 31 patients (41.9%) were seizure-free for at least 3 months, but 10 of these 13 patients (76.9%) experienced seizure recurrence during the 24-month follow-up period. Finally, at 24 months of the KD observational period, there was >50% response in 10 of the 31 patients (32.3%), including seizure-free patients (6 of 31 patients, 19.4%). Most of the patients (12 of 13, 92.3%) who experienced seizure freedom had >50% reduction in seizures within 1 month after initiating the KD, and this result was the only factor associated with seizure freedom in the current study. CONCLUSION The KD appeared to be an effective therapeutic modality for intractable pediatric epilepsy in TSC, but it did not exhibit guaranteed efficacy over a long-term period.
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Affiliation(s)
- Song Ee Youn
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea; Department of Pediatrics, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, South Korea
| | - Soyoung Park
- Department of Pediatrics, Soonchunhyang University Bucheon Hospital, Bucheon, South Korea
| | - Se Hee Kim
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea; Division of Pediatric Neurology, Epilepsy Research Institute, Severance Patients' Hospital, Seoul, South Korea
| | - Joon Soo Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea; Division of Pediatric Neurology, Epilepsy Research Institute, Severance Patients' Hospital, Seoul, South Korea
| | - Heung Dong Kim
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea; Division of Pediatric Neurology, Epilepsy Research Institute, Severance Patients' Hospital, Seoul, South Korea.
| | - Hoon-Chul Kang
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea; Division of Pediatric Neurology, Epilepsy Research Institute, Severance Patients' Hospital, Seoul, South Korea.
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31
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Kumari K, Sharma MC, Kakkar A, Malgulwar PB, Pathak P, Suri V, Sarkar C, Chandra SP, Faruq M. mTOR pathway activation in focal cortical dysplasia. Ann Diagn Pathol 2020; 46:151523. [PMID: 32325422 DOI: 10.1016/j.anndiagpath.2020.151523] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 02/21/2020] [Accepted: 03/24/2020] [Indexed: 01/05/2023]
Abstract
BACKGROUND Focal cortical dysplasia (FCD) is a localized cortical malformation and considerable morphological overlap exists between FCD IIB and neurological lesions associated with Tuberous sclerosis complex (TSC). Abnormal mTOR pathway secondary to somatic mTOR mutation and TSC gene mutation linked to PI3K/AKT/mTOR pathway have supported the hypothesis of common pathogenesis involved. Role of converging pathway, viz. Wnt/β-Catenin and mTOR is unknown in FCD. We aimed to analyse FCD IIB for TSC1/TSC2 mutations, immunoreactivity of hamartin, tuberin, mTOR and Wnt signalling cascades, and stem cell markers. MATERIALS AND METHODS Sixteen FCD IIB cases were retrieved along with 16 FCD IIA cases for comparison. Immunohistochemistry was performed for tuberin, hamartin, mTOR pathway markers, markers of stem cell phenotype, and Wnt pathway markers. Mutation analysis for TSC1 and TSC2 was performed by sequencing in 9 FCD cases. RESULTS All FCD cases showed preserved hamartin and tuberin immunoreactivity. Aberrant immunoreactivity of phospho-P70S6 kinase, S6 ribosomal, phospho-S6 ribosomal and Stat3 was noted in FCD IIB, with variable phospho-4E-BP1 (45%) and absent phospho-Stat3 expression. Immunoreactivity for phospho-P70S6 kinase (100%), S6 ribosomal protein (100%) and Stat3 (100%) was noted in FCD IIA, but not for phospho-S6 ribosomal, phospho-4E-BP1 and phospho-Stat3. c-Myc immunoreactivity was noted in all FCD cases. Nestin (81%) and Sox 2 (88%) stained balloon cells in FCD IIB (44%), while in FCD IIA cases were negative. All FCD cases were immunopositive for Wnt, but were negative for β-Catenin and cyclin-D1. TSC mutations were detected in two cases of FCD IIB. CONCLUSION Abnormal mTOR pathway activation exists in FCD IIB and IIA, however, shows differential immunoreactivity profile, indicating varying degrees of dysregulation. Labelling of neuronal stem cell markers in balloon cells suggests they are phenotypically immature. TSC1/2 mutation play role in the pathogenesis of FCD. Deep targeted sequencing is preferred diagnostic technique since conventional sanger sequencing often fails to detect low-allele frequency variants involved in mTOR/TSC pathway genes, commonly found in FCD.
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Affiliation(s)
- Kalpana Kumari
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Mehar C Sharma
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
| | - Aanchal Kakkar
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Prit B Malgulwar
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Pankaj Pathak
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Vaishali Suri
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Chitra Sarkar
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Sarat P Chandra
- Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India
| | - Mohammed Faruq
- Institute of Genomics and Integrative Biology - Council of Scientific and Industrial Research, New Delhi, India
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32
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Hodges SL, Lugo JN. Therapeutic role of targeting mTOR signaling and neuroinflammation in epilepsy. Epilepsy Res 2020; 161:106282. [DOI: 10.1016/j.eplepsyres.2020.106282] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/03/2020] [Accepted: 01/29/2020] [Indexed: 02/08/2023]
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Gericke B, Brandt C, Theilmann W, Welzel L, Schidlitzki A, Twele F, Kaczmarek E, Anjum M, Hillmann P, Löscher W. Selective inhibition of mTORC1/2 or PI3K/mTORC1/2 signaling does not prevent or modify epilepsy in the intrahippocampal kainate mouse model. Neuropharmacology 2019; 162:107817. [PMID: 31654704 DOI: 10.1016/j.neuropharm.2019.107817] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/26/2019] [Accepted: 10/18/2019] [Indexed: 12/23/2022]
Abstract
Dysregulation of the PI3K/Akt/mTOR pathway has been implicated in several brain disorders, including epilepsy. Rapamycin and similar compounds inhibit mTOR. complex 1 and have been reported to decrease seizures, delay seizure development, or prevent epileptogenesis in different animal models of genetic or acquired epilepsies. However, data for acquired epilepsy are inconsistent, which, at least in part, may be due to the poor brain penetration and long brain persistence of rapamycin and the fact that it blocks only one of the two cellular mTOR complexes. Here we examined the antiepileptogenic or disease-modifying effects of two novel, brain-permeable and well tolerated 1,3,5-triazine derivatives, the ATP-competitive mTORC1/2 inhibitor PQR620 and the dual pan-PI3K/mTORC1/2 inhibitor PQR530 in the intrahippocampal kainate mouse model, in which spontaneous seizures develop after status epilepticus (SE). Following kainate injection, the two compounds were administered over 2 weeks at doses previously been shown to block mTORC1/2 or PI3K/mTORC1/2 in the mouse brain. When spontaneous seizures were recorded by continuous (24/7) video-EEG recording starting 6 weeks after termination of treatment, no effects on incidence or frequency of seizures were observed. Drug treatment suppressed the epilepsy-induced activation of the PI3K/Akt/mTOR pathway in the hippocampus, but granule cell dispersion in the dentate gyrus was not prevented. When epilepsy-associated behavioral alterations were determined 12-14 weeks after kainate, mice pretreated with PQR620 or PQR530 exhibited reduced anxiety-related behavior in the light-dark box, indicating a disease-modifying effect. Overall, the data indicate that mTORC1/C2 or PI3K/mTORC1/C2 inhibition may not be an antiepileptogenic strategy for SE-induced epilepsy.
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Affiliation(s)
- Birthe Gericke
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Claudia Brandt
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Wiebke Theilmann
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Lisa Welzel
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Alina Schidlitzki
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Friederike Twele
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Edith Kaczmarek
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Muneeb Anjum
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | | | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
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Chen SG, Tsai CH, Lin CJ, Lee CC, Yu HY, Hsieh TH, Liu HL. Transcranial focused ultrasound pulsation suppresses pentylenetetrazol induced epilepsy in vivo. Brain Stimul 2019; 13:35-46. [PMID: 31575487 DOI: 10.1016/j.brs.2019.09.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 09/04/2019] [Accepted: 09/23/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Epilepsy is a neurological disorder characterized by abnormal neuron discharge, and one-third of epilepsy patients suffer from drug-resistant epilepsy (DRE). The current management for DRE includes epileptogenic lesion resection, disconnection, and neuromodulation. Neuromodulation is achieved through invasive electrical stimulus including deep brain stimulation, vagus nerve stimulation, or responsive neurostimulation (RNS). As an alternative therapy, transcranial focused ultrasound (FUS) can transcranially and non-invasively modulate neuron activity. OBJECTIVE This study seeks to verify the use of FUS pulsations to suppress spikes in an acute epileptic small-animal model, and to investigate possible biological mechanisms by which FUS pulsations interfere with epileptic neuronal activity. METHODS The study used a total of 76 Sprague-Dawley rats. For the epilepsy model, rats were administered pentylenetetrazol (PTZ) to induce acute epileptic-like abnormal neuron discharges, followed by FUS exposure. Various ultrasound parameters were set to test the epilepsy-suppressing effect, while concurrently monitoring and analyzing electroencephalogram (EEG) signals. Animal behavior was monitored and histological examinations were conducted to evaluate the hazard posed by ultrasound exposure and the expression of neuronal activity markers. Western blotting was used to evaluate the correlation between FUS-induced epileptic suppression and the PI3K-mTOR signaling pathway. RESULTS We observed that FUS pulsations effectively suppressed epileptic activity and observed EEG spectrum oscillations; the spike-suppressing effect depended on the selection of ultrasound parameters and highly correlated with FUS exposure level. Expression level changes of c-Fos and GAD65 were confirmed in the cortex and hippocampus, indicating that FUS pulsations deactivated excitatory cells and activated GABAergic terminals. No tissue damage, inflammatory response, or behavioral abnormalities were observed in rats treated with FUS under these exposure parameters. We also found that the FUS pulsations down-regulated the S6 phosphorylation and decreased pAKT expression. CONCLUSION Our results suggest that pulsed FUS exposure effectively suppresses epileptic spikes in an acute epilepsy animal model, and finds that ultrasound pulsation interferes with neuronal activity and affects the PTZ-induced PI3K-Akt-mTOR pathway, which might help explain the mechanism underlying ultrasound-related epileptic spike control.
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Affiliation(s)
- Sin-Guang Chen
- Department of Electrical Engineering, Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan; Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region
| | - Chih-Hung Tsai
- Department of Electrical Engineering, Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Chia-Jung Lin
- Department of Electrical Engineering, Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Cheng-Chia Lee
- Department of Neurosurgery, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine and Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Hsiang-Yu Yu
- School of Medicine and Brain Research Center, National Yang-Ming University, Taipei, Taiwan; Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Tsung-Hsun Hsieh
- School of Physical Therapy and Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan; Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan.
| | - Hao-Li Liu
- Department of Electrical Engineering, Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan; Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
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Coding and non-coding transcriptome of mesial temporal lobe epilepsy: Critical role of small non-coding RNAs. Neurobiol Dis 2019; 134:104612. [PMID: 31533065 DOI: 10.1016/j.nbd.2019.104612] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/21/2019] [Accepted: 09/06/2019] [Indexed: 02/06/2023] Open
Abstract
Our understanding of mesial temporal lobe epilepsy (MTLE), one of the most common form of drug-resistant epilepsy in humans, is derived mainly from clinical, imaging, and physiological data from humans and animal models. High-throughput gene expression studies of human MTLE have the potential to uncover molecular changes underlying disease pathogenesis along with novel therapeutic targets. Using RNA- and small RNA-sequencing in parrallel, we explored differentially expressed genes in the hippocampus and cortex of MTLE patients who had undergone surgical resection and non-epileptic controls. We identified differentially expressed genes in the hippocampus of MTLE patients and differentially expressed small RNAs across both the cortex and hippocampus. We found significant enrichment for astrocytic and microglial genes among up-regulated genes, and down regulation of neuron specific genes in the hippocampus of MTLE patients. The transcriptome profile of the small RNAs reflected disease state more robustly than mRNAs, even across brain regions which show very little pathology. While mRNAs segregated predominately by brain region for MTLE and controls, small RNAs segregated by disease state. In particular, our data suggest that specific miRNAs (e.g., let-7b-3p and let-7c-3p) may be key regulators of multiple pathways related to MTLE pathology. Further, we report a strong association of other small RNA species with MTLE pathology. As such we have uncovered novel elements that may contribute to the establishment and progression of MTLE pathogenesis and that could be leveraged as therapeutic targets.
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36
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Tahmasebi S, Khoutorsky A, Mathews MB, Sonenberg N. Translation deregulation in human disease. Nat Rev Mol Cell Biol 2019; 19:791-807. [PMID: 30038383 DOI: 10.1038/s41580-018-0034-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Advances in sequencing and high-throughput techniques have provided an unprecedented opportunity to interrogate human diseases on a genome-wide scale. The list of disease-causing mutations is expanding rapidly, and mutations affecting mRNA translation are no exception. Translation (protein synthesis) is one of the most complex processes in the cell. The orchestrated action of ribosomes, tRNAs and numerous translation factors decodes the information contained in mRNA into a polypeptide chain. The intricate nature of this process renders it susceptible to deregulation at multiple levels. In this Review, we summarize current evidence of translation deregulation in human diseases other than cancer. We discuss translation-related diseases on the basis of the molecular aberration that underpins their pathogenesis (including tRNA dysfunction, ribosomopathies, deregulation of the integrated stress response and deregulation of the mTOR pathway) and describe how deregulation of translation generates the phenotypic variability observed in these disorders.
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Affiliation(s)
- Soroush Tahmasebi
- Goodman Cancer Research Center, McGill University, Montreal, Quebec, Canada. .,Department of Biochemistry, McGill University, Montreal, Quebec, Canada. .,Department of Pharmacology, University of Illinois at Chicago, Chicago, IL, USA.
| | - Arkady Khoutorsky
- Department of Anesthesia and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Canada
| | - Michael B Mathews
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Nahum Sonenberg
- Goodman Cancer Research Center, McGill University, Montreal, Quebec, Canada. .,Department of Biochemistry, McGill University, Montreal, Quebec, Canada.
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[Chinese expert consensus on surgical treatment of tuberous sclerosis complex-related epilepsy]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2019; 21:735-742. [PMID: 31416495 PMCID: PMC7389894 DOI: 10.7499/j.issn.1008-8830.2019.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/02/2019] [Indexed: 06/10/2023]
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38
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Soares JI, Da Costa C, Ferreira MH, Andrade PA, Maia GH, Lukoyanov NV. Partial depletion of septohippocampal cholinergic cells reduces seizure susceptibility, but does not mitigate hippocampal neurodegeneration in the kainate model of epilepsy. Brain Res 2019; 1717:235-246. [DOI: 10.1016/j.brainres.2019.04.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/22/2019] [Accepted: 04/23/2019] [Indexed: 02/06/2023]
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39
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Wang Y, Chen Z. An update for epilepsy research and antiepileptic drug development: Toward precise circuit therapy. Pharmacol Ther 2019; 201:77-93. [PMID: 31128154 DOI: 10.1016/j.pharmthera.2019.05.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 12/14/2022]
Abstract
Epilepsy involves neuronal dysfunction at molecular, cellular, and circuit levels. The understanding of the mechanism of the epilepsies has advanced greatly in the last three decades, especially in terms of their cellular and molecular basis. However, despite the availability of ~30 anti-epileptic drugs (AEDs) with diverse molecular targets, there are still many challenges (e.g. drug resistance, side effects) in pharmacological treatment of epilepsies today. Because molecular mechanisms are integrated at the level of neuronal circuits, we suggest a shift in epilepsy treatment and research strategies from the "molecular" level to the "circuit" level. Recent technological advances have facilitated circuit mechanistic discovery at each level and have paved the way for many opportunities of novel therapeutic strategies and AED development toward precise circuit therapy.
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Affiliation(s)
- Yi Wang
- Institute of Pharmacology and Toxicology, Department of Pharmacology, NHC and CAMS Key Laboratory of Medical Neurobiology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhong Chen
- Institute of Pharmacology and Toxicology, Department of Pharmacology, NHC and CAMS Key Laboratory of Medical Neurobiology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China; Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
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40
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Glia activation of eukaryotic translation initiation factor 4e-binding protein 1 in temporal lobe epilepsy. Neuroreport 2019; 30:222-226. [PMID: 30672889 DOI: 10.1097/wnr.0000000000001188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study was aimed to investigate whether 4e-binding protein 1 is activated during temporal lobe epileptogenesis. We used the hippocampus of patients with refractory temporal lobe epilepsy (TLE), diagnosed with hippocampal sclerosis (HS) or non-HS, to examine the distribution of phospho-4e-binding protein 1 (p4EBP1) by immunohistochemical staining (n=3-5). We also examined p4EBP1 in the kainic acid (KA)-induced mouse model of TLE before and after anticonvulsant treatment (n=3 per group). The results showed that the hippocampus of both patients with HS and KA mouse model displayed significantly upregulated p4EBP1 immunoreactivity in glial fibrillary acidic protein-positive astrocytes in hippocampus. Quantitative results showed that there is a 5.9-fold upregulation in the number of p4EBP1+glia-like cells in TLE group than control group (P<0.05). However, treatment with lamotrigine failed to suppress spontaneous seizures and did not affect the astrocytic distribution of p4EBP1 (P=0.73). Taken together, we investigated the spatiotemporal expression of p4EBP1 in the sclerotic hippocampus of both patients and a KA-induced mouse model and found glia activation of 4e-binding protein 1 in TLE. Our findings suggest that the upregulation of p4EBP1 in astrocytes may play a critical role in the pathogenesis of TLE.
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41
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Engel T, Gómez-Sintes R, Alves M, Jimenez-Mateos EM, Fernández-Nogales M, Sanz-Rodriguez A, Morgan J, Beamer E, Rodríguez-Matellán A, Dunleavy M, Sano T, Avila J, Medina M, Hernandez F, Lucas JJ, Henshall DC. Bi-directional genetic modulation of GSK-3β exacerbates hippocampal neuropathology in experimental status epilepticus. Cell Death Dis 2018; 9:969. [PMID: 30237424 PMCID: PMC6147910 DOI: 10.1038/s41419-018-0963-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/20/2018] [Accepted: 07/25/2018] [Indexed: 12/31/2022]
Abstract
Glycogen synthase kinase-3 (GSK-3) is ubiquitously expressed throughout the brain and involved in vital molecular pathways such as cell survival and synaptic reorganization and has emerged as a potential drug target for brain diseases. A causal role for GSK-3, in particular the brain-enriched GSK-3β isoform, has been demonstrated in neurodegenerative diseases such as Alzheimer’s and Huntington’s, and in psychiatric diseases. Recent studies have also linked GSK-3 dysregulation to neuropathological outcomes in epilepsy. To date, however, there has been no genetic evidence for the involvement of GSK-3 in seizure-induced pathology. Status epilepticus (prolonged, damaging seizure) was induced via a microinjection of kainic acid into the amygdala of mice. Studies were conducted using two transgenic mouse lines: a neuron-specific GSK-3β overexpression and a neuron-specific dominant-negative GSK-3β (GSK-3β-DN) expression in order to determine the effects of increased or decreased GSK-3β activity, respectively, on seizures and attendant pathological changes in the hippocampus. GSK-3 inhibitors were also employed to support the genetic approach. Status epilepticus resulted in a spatiotemporal regulation of GSK-3 expression and activity in the hippocampus, with decreased GSK-3 activity evident in non-damaged hippocampal areas. Consistent with this, overexpression of GSK-3β exacerbated status epilepticus-induced neurodegeneration in mice. Surprisingly, decreasing GSK-3 activity, either via overexpression of GSK-3β-DN or through the use of specific GSK-3 inhibitors, also exacerbated hippocampal damage and increased seizure severity during status epilepticus. In conclusion, our results demonstrate that the brain has limited tolerance for modulation of GSK-3 activity in the setting of epileptic brain injury. These findings caution against targeting GSK-3 as a treatment strategy for epilepsy or other neurologic disorders where neuronal hyperexcitability is an underlying pathomechanism.
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Affiliation(s)
- Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland.
| | - Raquel Gómez-Sintes
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CIB-CSIC, C/Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Mariana Alves
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Eva M Jimenez-Mateos
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Marta Fernández-Nogales
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Amaya Sanz-Rodriguez
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - James Morgan
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Edward Beamer
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Alberto Rodríguez-Matellán
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Mark Dunleavy
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Takanori Sano
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Jesus Avila
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Miguel Medina
- CIEN Foundation-Queen Sofia Foundation Alzheimer Center and CIBERNED, Instituto de Salud Carlos III Madrid, Madrid, Spain
| | - Felix Hernandez
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - José J Lucas
- Department of Molecular Neuropathology, Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas (CSIC)/Universidad Autónoma de Madrid (UAM) and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - David C Henshall
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2, Ireland.,FutureNeuro Research Centre, Dublin 2, Ireland
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Ragulator and SLC38A9 activate the Rag GTPases through noncanonical GEF mechanisms. Proc Natl Acad Sci U S A 2018; 115:9545-9550. [PMID: 30181260 DOI: 10.1073/pnas.1811727115] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) growth pathway detects nutrients through a variety of sensors and regulators that converge on the Rag GTPases, which form heterodimers consisting of RagA or RagB tightly bound to RagC or RagD and control the subcellular localization of mTORC1. The Rag heterodimer uses a unique "locking" mechanism to stabilize its active (GTPRagA-RagCGDP) or inactive (GDPRagA-RagCGTP) nucleotide states. The Ragulator complex tethers the Rag heterodimer to the lysosomal surface, and the SLC38A9 transmembrane protein is a lysosomal arginine sensor that upon activation stimulates mTORC1 activity through the Rag GTPases. How Ragulator and SLC38A9 control the nucleotide loading state of the Rag GTPases remains incompletely understood. Here we find that Ragulator and SLC38A9 are each unique guanine exchange factors (GEFs) that collectively push the Rag GTPases toward the active state. Ragulator triggers GTP release from RagC, thus resolving the locked inactivated state of the Rag GTPases. Upon arginine binding, SLC38A9 converts RagA from the GDP- to the GTP-loaded state, and therefore activates the Rag GTPase heterodimer. Altogether, Ragulator and SLC38A9 act on the Rag GTPases to activate the mTORC1 pathway in response to nutrient sufficiency.
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43
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Curatolo P, Moavero R, van Scheppingen J, Aronica E. mTOR dysregulation and tuberous sclerosis-related epilepsy. Expert Rev Neurother 2018; 18:185-201. [DOI: 10.1080/14737175.2018.1428562] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
| | - Romina Moavero
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
- Child Neurology Unit, Neuroscience and Neurorehabilitation Department, “Bambino Gesù” Children’s Hospital, IRCCS, Rome, Italy
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), The Netherlands
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Abstract
Childhood epileptic encephalopathies are age-dependent disorders of the brain whose hallmarks include loss of neurologic function over time, abnormal electroencephalographic findings, and seizures. Ictal and interictal electrographic activity are conjointly thought to be at the root of the often devastating neuropsychological deterioration, which is specific to the maturing brain. The goals of treatment are not only to control seizures, but also to prevent or reverse neurologic loss of function. In general, time is of the essence in diagnosis, and experienced specialists should promptly design a treatment plan. Hormonal and immune therapies are at the forefront of treatment in many cases, with traditional antiepileptic drugs and surgery (when an identifiable lesion is present) playing a limited role. However, gold standard evidence for treatment of epileptic encephalopathies remains limited. Ongoing clinical and basic research may lead to better understanding of these catastrophic conditions and to better and more effective therapies.
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Affiliation(s)
- Hiroki Nariai
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Susan Duberstein
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, USA,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA
| | - Shlomo Shinnar
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, USA,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA,Department of Epidemiology and Population Health, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, NY, USA
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45
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Jeong A, Wong M. Targeting the Mammalian Target of Rapamycin for Epileptic Encephalopathies and Malformations of Cortical Development. J Child Neurol 2018; 33:55-63. [PMID: 29246093 PMCID: PMC5739082 DOI: 10.1177/0883073817696814] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Malformations of cortical development represent a common cause of epileptic encephalopathies and drug-resistant epilepsy in children. As current treatments are often ineffective, new therapeutic targets are needed for epileptic encephalopathies associated with cortical malformations. The mechanistic/mammalian target of rapamycin (mTOR) pathway constitutes a signaling pathway that drives cellular and molecular mechanisms of epileptogenesis in a variety of focal cortical malformations. mTOR inhibitors prevent epilepsy and associated pathogenic mechanisms of epileptogenesis in mouse models of tuberous sclerosis complex and are currently in clinical trials for drug-resistant seizures in these patients. A recent explosion of genetic studies has linked mutations in various genes regulating the mTOR pathway to other cortical malformations, such as focal cortical dysplasia and hemimegalencephaly. Thus, mTOR inhibitors represent promising candidates as novel antiseizure and antiepileptogenic therapies for epilepsy associated with a spectrum of cortical malformations.
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Affiliation(s)
- Anna Jeong
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, USA
| | - Michael Wong
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, USA
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Shen K, Choe A, Sabatini DM. Intersubunit Crosstalk in the Rag GTPase Heterodimer Enables mTORC1 to Respond Rapidly to Amino Acid Availability. Mol Cell 2017; 68:552-565.e8. [PMID: 29056322 PMCID: PMC5674802 DOI: 10.1016/j.molcel.2017.09.026] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/14/2017] [Accepted: 09/19/2017] [Indexed: 01/03/2023]
Abstract
mTOR complex I (mTORC1) is a central growth regulator that senses amino acids through a pathway that converges on the Rag GTPases, an obligate heterodimer of two related GTPases. Despite their central role in amino acid sensing, it is unknown why the Rag GTPases are heterodimeric and whether their subunits communicate with each other. Here, we find that the binding of guanosine triphosphate (GTP) to one subunit inhibits the binding and induces the hydrolysis of GTP by the other. This intersubunit communication pushes the Rag GTPases into either of two stable configurations, which represent active "on" or "off" states that interconvert via transient intermediates. Subunit coupling confers on the mTORC1 pathway its capacity to respond rapidly to the amino acid level. Thus, the dynamic response of mTORC1 requires intersubunit communication by the Rag GTPases, providing a rationale for why they exist as a dimer and revealing a distinct mode of control for a GTP-binding protein.
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Affiliation(s)
- Kuang Shen
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 9 Cambridge Center, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Abigail Choe
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - David M Sabatini
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 9 Cambridge Center, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 7 Cambridge Center, Cambridge, MA 02142, USA.
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Zou J, Zhang B, Gutmann DH, Wong M. Postnatal reduction of tuberous sclerosis complex 1 expression in astrocytes and neurons causes seizures in an age-dependent manner. Epilepsia 2017; 58:2053-2063. [PMID: 29023667 DOI: 10.1111/epi.13923] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2017] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Epilepsy is one of the most prominent symptoms of tuberous sclerosis complex (TSC), a genetic disorder, and may be related to developmental defects resulting from impaired TSC1 or TSC2 gene function in astrocytes and neurons. Inactivation of the Tsc1 gene driven by a glial-fibrillary acidic protein (GFAP) promoter during embryonic brain development leads to widespread pathologic effects on astrocytes and neurons, culminating in severe, progressive epilepsy in mice (Tsc1GFAP-Cre mice). However, the developmental timing and cellular specificity relevant to epileptogenesis in this model has not been well defined. The present study evaluates the effect of postnatal Tsc1 gene inactivation on pathologic features of astrocytes and neurons and development of epilepsy. METHODS An inducible Tsc1 knock-out mouse was created utilizing a tamoxifen-driven GFAP-CreER line (Tsc1GFAP-CreER mice) with TSC1 reduction induced postnatally at 2 and 6 weeks of age, and compared to conventional Tsc1GFAP-Cre mice with prenatal TSC1 reduction. Western blotting, immunohistochemistry, histology, and video-electroencephalography (EEG) assessed mechanistic target of rapamycin (mTOR) pathway activation, astrogliosis, neuronal organization, and spontaneous seizures, respectively. RESULTS Tsc1 gene inactivation at 2 weeks of age was sufficient to cause astrogliosis and mild epilepsy in Tsc1GFAP-CreER mice, but the phenotype was much less severe than that observed with prenatal Tsc1 gene inactivation in Tsc1GFAP-Cre mice. Both astrocytes and neurons were affected by prenatal and postnatal Tsc1 gene activation to a degree similar to the severity of epilepsy, suggesting that both cellular types may contribute to epileptogenesis. SIGNIFICANCE These findings support a model in which the developmental timing of TSC1 loss dictates the severity of neuronal and glial abnormalities and resulting epilepsy.
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Affiliation(s)
- Jia Zou
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, U.S.A
| | - Bo Zhang
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, U.S.A
| | - David H Gutmann
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, U.S.A
| | - Michael Wong
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, U.S.A
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48
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Kambli L, Bhatt LK, Oza M, Prabhavalkar K. Novel therapeutic targets for epilepsy intervention. Seizure 2017; 51:27-34. [DOI: 10.1016/j.seizure.2017.07.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 07/23/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
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mTOR inhibitor reverses autistic-like social deficit behaviours in adult rats with both Tsc2 haploinsufficiency and developmental status epilepticus. Eur Arch Psychiatry Clin Neurosci 2017; 267:455-463. [PMID: 27263037 DOI: 10.1007/s00406-016-0703-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 05/23/2016] [Indexed: 12/25/2022]
Abstract
Epilepsy is a major risk factor for autism spectrum disorder (ASD) and complicates clinical manifestations and management of ASD significantly. Tuberous sclerosis complex (TSC), caused by TSC1 or TSC2 mutations, is one of the medical conditions most commonly associated with ASD and has become an important model to examine molecular pathways associated with ASD. Previous research showed reversal of autism-like social deficits in Tsc1 +/- and Tsc2 +/- mouse models by mammalian target of rapamycin (mTOR) inhibitors. However, at least 70 % of individuals with TSC also have epilepsy, known to complicate the severity and treatment responsiveness of the behavioural phenotype. No previous study has examined the impact of seizures on neurocognitive reversal by mTOR inhibitors. Adult Tsc2 +/- (Eker)-rats express social deficits similar to Tsc2 +/- mice, with additive social deficits from developmental status epilepticus (DSE). DSE was induced by intraperitoneal injection with kainic acid at post-natal days P7 and P14 (n = 12). The experimental group that modelled TSC pathology carried the Tsc2 +/- (Eker)-mutation and was challenged with DSE. The wild-type controls had not received DSE (n = 10). Four-month-old animals were analysed for social behaviour (T1), then treated three times during 1 week with 1 mg/kg everolimus and finally retested in the post-treatment behavioural analysis (T2). In the experimental group, both social interaction and social cognition were impaired at T1. After treatment at T2, behaviour in the experimental group was indistinguishable from controls. The mTOR inhibitor, everolimus, reversed social deficit behaviours in the Tsc2 haploinsufficiency plus DSE animal model to control levels.
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Łukawski K, Andres-Mach M, Czuczwar M, Łuszczki JJ, Kruszyński K, Czuczwar SJ. Mechanisms of epileptogenesis and preclinical approach to antiepileptogenic therapies. Pharmacol Rep 2017; 70:284-293. [PMID: 29477036 DOI: 10.1016/j.pharep.2017.07.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/17/2017] [Accepted: 07/12/2017] [Indexed: 12/30/2022]
Abstract
The prevalence of epilepsy is estimated 5-10 per 1000 population and around 70% of patients with epilepsy can be sufficiently controlled by antiepileptic drugs (AEDs). Epileptogenesis is the process responsible for converting normal into an epileptic brain and mechanisms responsible include among others: inflammation, neurodegeneration, neurogenesis, neural reorganization and plasticity. Some AEDs may be antiepileptiogenic (diazepam, eslicarbazepine) but the correlation between neuroprotection and inhibition of epileptogenesis is not evident. Antiepileptogenic activity has been postulated for mTOR ligands, resveratrol and losartan. So far, clinical evidence gives some hope for levetiracetam as an AED inhibiting epileptogenesis in neurosurgical patients. Biomarkers for epileptogenesis are needed for the proper selection of patients for evaluation of potential antiepileptogenic compounds.
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Affiliation(s)
- Krzysztof Łukawski
- Department of Physiopathology, Institute of Rural Health, Lublin, Poland; Department of Pathophysiology, Medical University of Lublin, Lublin, Poland
| | - Marta Andres-Mach
- Isobolographic Analysis Laboratory, Institute of Rural Health, Lublin, Poland
| | - Mirosław Czuczwar
- 2nd Department of Anesthesiology and Intensive Care, Medical University of Lublin, Lublin, Poland
| | - Jarogniew J Łuszczki
- Department of Pathophysiology, Medical University of Lublin, Lublin, Poland; Isobolographic Analysis Laboratory, Institute of Rural Health, Lublin, Poland
| | | | - Stanisław J Czuczwar
- Department of Physiopathology, Institute of Rural Health, Lublin, Poland; Department of Pathophysiology, Medical University of Lublin, Lublin, Poland.
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