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Richard MA, Lupo PJ, Ehli EA, Sahin M, Krueger DA, Wu JY, Bebin EM, Au KS, Northrup H, Farach LS. Common epilepsy variants from the general population are not associated with epilepsy among individuals with tuberous sclerosis complex. Am J Med Genet A 2024; 194:e63569. [PMID: 38366765 PMCID: PMC11060940 DOI: 10.1002/ajmg.a.63569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/26/2024] [Accepted: 02/02/2024] [Indexed: 02/18/2024]
Abstract
Common genetic variants identified in the general population have been found to increase phenotypic risks among individuals with certain genetic conditions. Up to 90% of individuals with tuberous sclerosis complex (TSC) are affected by some type of epilepsy, yet the common variants contributing to epilepsy risk in the general population have not been evaluated in the context of TSC-associated epilepsy. Such knowledge is important to help uncover the underlying pathogenesis of epilepsy in TSC which is not fully understood, and critical as uncontrolled epilepsy is a major problem in this population. To evaluate common genetic modifiers of epilepsy, our study pooled phenotypic and genotypic data from 369 individuals with TSC to evaluate known and novel epilepsy common variants. We did not find evidence of enhanced genetic penetrance for known epilepsy variants identified across the largest genome-wide association studies of epilepsy in the general population, but identified support for novel common epilepsy variants in the context of TSC. Specifically, we have identified a novel signal in SLC7A1 that may be functionally involved in pathways relevant to TSC and epilepsy. Our study highlights the need for further evaluation of genetic modifiers in TSC to aid in further understanding of epilepsy in TSC and improve outcomes.
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Affiliation(s)
- Melissa A Richard
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas, USA
| | - Philip J Lupo
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas, USA
| | - Erik A Ehli
- Avera Institute for Human Genetics, Sioux Falls, South Dakota, USA
| | - Mustafa Sahin
- Department of Neurology, Rosamund Stone Zander Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Darcy A Krueger
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Joyce Y Wu
- Epilepsy Center, Division of Pediatric Neurology, Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
- Department of Pediatrics, Division of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Elizabeth M Bebin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Kit Sing Au
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Hope Northrup
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Laura S Farach
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
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Takahashi K, Rensing NR, Eultgen EM, Wang SH, Nelvagal HR, Le SQ, Roberts MS, Doray B, Han EB, Dickson PI, Wong M, Sands MS, Cooper JD. GABAergic interneurons contribute to the fatal seizure phenotype of CLN2 disease mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.29.587276. [PMID: 38585903 PMCID: PMC10996664 DOI: 10.1101/2024.03.29.587276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
GABAergic interneuron deficits have been implicated in the epileptogenesis of multiple neurological diseases. While epileptic seizures are a key clinical hallmark of CLN2 disease, a childhood-onset neurodegenerative lysosomal storage disorder caused by a deficiency of tripeptidyl peptidase 1 (TPP1), the etiology of these seizures remains elusive. Given that Cln2 R207X/R207X mice display fatal spontaneous seizures and an early loss of several cortical interneuron populations, we hypothesized that those two events might be causally related. To address this hypothesis, we first generated an inducible transgenic mouse expressing lysosomal membrane-tethered TPP1 (TPP1LAMP1) on the Cln2 R207X/R207X genetic background to study the cell-autonomous effects of cell-type-specific TPP1 deficiency. We crossed the TPP1LAMP1 mice with Vgat-Cre mice to introduce interneuron-specific TPP1 deficiency. Vgat-Cre ; TPP1LAMP1 mice displayed storage material accumulation in several interneuron populations both in cortex and striatum, and increased susceptibility to die after PTZ-induced seizures. Secondly, to test the role of GABAergic interneuron activity in seizure progression, we selectively activated these cells in Cln2 R207X/R207X mice using Designer Receptor Exclusively Activated by Designer Drugs (DREADDs) in in Vgat-Cre : Cln2 R207X/R207X mice. EEG monitoring revealed that DREADD-mediated activation of interneurons via chronic deschloroclozapine administration accelerated the onset of spontaneous seizures and seizure-associated death in Vgat-Cre : Cln2 R207X/R207X mice, suggesting that modulating interneuron activity can exert influence over epileptiform abnormalities in CLN2 disease. Taken together, these results provide new mechanistic insights into the underlying etiology of seizures and premature death that characterize CLN2 disease.
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Ng ACH, Choudhary A, Barrett KT, Gavrilovici C, Scantlebury MH. Mechanisms of infantile epileptic spasms syndrome: What have we learned from animal models? Epilepsia 2024; 65:266-280. [PMID: 38036453 DOI: 10.1111/epi.17841] [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: 10/02/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/02/2023]
Abstract
The devastating developmental and epileptic encephalopathy of infantile epileptic spasms syndrome (IESS) has numerous causes, including, but not limited to, brain injury, metabolic, and genetic conditions. Given the stereotyped electrophysiologic, age-dependent, and clinical findings, there likely exists one or more final common pathways in the development of IESS. The identity of this final common pathway is unknown, but it may represent a novel therapeutic target for infantile spasms. Previous research on IESS has focused largely on identifying the neuroanatomic substrate using specialized neuroimaging techniques and cerebrospinal fluid analysis in human patients. Over the past three decades, several animal models of IESS were created with an aim to interrogate the underlying pathogenesis of IESS, to identify novel therapeutic targets, and to test various treatments. Each of these models have been successful at recapitulating multiple aspects of the human IESS condition. These animal models have implicated several different molecular pathways in the development of infantile spasms. In this review we outline the progress that has been made thus far using these animal models and discuss future directions to help researchers identify novel treatments for drug-resistant IESS.
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Affiliation(s)
- Andy Cheuk-Him Ng
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Anamika Choudhary
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Karlene T Barrett
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Cezar Gavrilovici
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Morris H Scantlebury
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Hollenshead PP, Jackson CN, Cross JV, Witten TE, Anwar AI, Ahmadzadeh S, Shekoohi S, Kaye AD. Treatment modalities for infantile spasms: current considerations and evolving strategies in clinical practice. Neurol Sci 2024; 45:507-514. [PMID: 37736852 DOI: 10.1007/s10072-023-07078-z] [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: 07/02/2023] [Accepted: 09/13/2023] [Indexed: 09/23/2023]
Abstract
Infantile spasms, newly classified as infantile epileptic spasm syndrome (IESS), occur in children under 2 years of age and present as an occur as brief, symmetrical, contractions of the musculature of the neck, trunk, and extremities. When infantile spasms occur with a concomitant hypsarrhythmia on electroencephalogram (EEG) and developmental regression, it is known as West Syndrome. There is no universally accepted mainstay of treatment for this condition, but some options include synthetic adrenocorticotropic hormone (ACTH), repository corticotropin injection (RCI/Acthar Gel), corticosteroids, valproic acid, vigabatrin, and surgery. Without effective treatment, infantile spasms can cause an impairment of psychomotor development and/or cognitive and behavioral functions. The first-line treatment in the USA is ACTH related to high efficacy for cessation of infantile spasms long-term and low-cost profile. Acthar Gel is a repository corticotropin intramuscular injection that became FDA-approved for the treatment of IESS in 2010. Though it is believed that ACTH, Acthar Gel, and corticosteroids all work via a negative feedback pathway to decrease corticotropin-releasing hormone (CRH) release, their safety and efficacy profiles all vary. Vigabatrin and valproic acid are both anti-seizure medications that work by increasing GABA concentrations in the CNS and decreasing excitatory activity. Acthar Gel has been shown to have superior efficacy and a diminished side effect profile when compared with other treatment modalities.
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Affiliation(s)
- Payton P Hollenshead
- School of Medicine, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
| | - Corrie N Jackson
- School of Medicine, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
| | - Jordan V Cross
- School of Medicine, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
| | - Taylor E Witten
- School of Medicine, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
| | - Ahmed I Anwar
- Department of Behavioral Neuroscience, Quinnipiac University, 275 Mount Carmel Ave, Hamden, CT, 06518, USA
| | - Shahab Ahmadzadeh
- Department of Anesthesiology, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
| | - Sahar Shekoohi
- Department of Anesthesiology, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA.
| | - Alan D Kaye
- Department of Anesthesiology, Department of Pharmacology, Toxicology, and Neurosciences, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA, 71103, USA
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Kuchenbuch M, Lo Barco T, Chemaly N, Chiron C, Nabbout R. Fifteen years of real-world data on the use of vigabatrin in individuals with infantile epileptic spasms syndrome. Epilepsia 2024; 65:430-444. [PMID: 37872396 DOI: 10.1111/epi.17808] [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: 03/17/2023] [Revised: 10/14/2023] [Accepted: 10/19/2023] [Indexed: 10/25/2023]
Abstract
OBJECTIVE This study was undertaken to evaluate our treatment algorithm for infantile epileptic spasms syndrome (IESS) used between 2000 and 2018. We initiated vigabatrin (VGB), and steroids were added if the electroclinical response (spasms and electroencephalogram [EEG]) to VGB was not obtained or incomplete. METHODS Individuals with IESS treated with VGB were recruited from our hospital clinical data warehouse based on electronic health records (EHRs) generated since 2009 and containing relevant keywords. We confirmed the diagnosis of IESS. Clinical, EEG, imaging, and biological data were extracted from the EHRs. We analyzed factors associated with short-term response, time to response, relapse, time to relapse of spasms, and the presence of spasms at last follow-up. RESULTS We collected data from 198 individuals (female: 46.5%, IESS onset: 6 [4.5-10.3] months, follow-up: 4.6 [2.5-7.6] years, median [Q1-Q3]) including 129 (65.2%) with identifiable etiology. VGB was started 17 (5-57.5) days after IESS diagnosis. A total of 113 individuals were responders (57.1% of the cohort), 64 with VGB alone and 38 with VGB further combined with steroids (56.6% and 33.6% of responders, respectively). Among responders, 33 (29%) experienced relapses of spasms, mostly those with later onset of spasms (p = .002) and those who received VGB for <24 months after spasms cessation compared to a longer duration on VGB (45% vs. 12.8%, p = .003). At follow-up, 92 individuals were seizure-free (46.5% of the whole cohort), including 26 free of therapy (13.1%). One hundred twelve individuals (56.6%) were still receiving VGB, with a duration of 3.2 (1.75-5.7) years. SIGNIFICANCE Our sequential protocol introducing VGB then adding steroids is an effective alternative to a combined VGB-steroids approach in IESS. It avoids steroid-related adverse events, as well as those from VGB-steroid combination. According to our data, a period of 7 days seems sufficient to assess VGB response and enables the addition of steroids rapidly if needed. Continuing VGB for 2 years may balance the risk of relapse and treatment-induced adverse events.
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Affiliation(s)
- Mathieu Kuchenbuch
- Department of Pediatric Neurology, Reference Center for Rare Epilepsies, Hôpital Necker-Enfants Malades, member of ERN EpiCARE, Paris, France
- Laboratory of Translational Research for Neurological Disorders, INSERM MR1163, Imagine Institute, Paris, France
- Service de Pédiatrie, Reference Center for Rare Epilepsies, member of ERN EpiCARE, Université de Lorraine, CHRU-Nancy, Nancy, France
| | - Tommaso Lo Barco
- Department of Pediatric Neurology, Reference Center for Rare Epilepsies, Hôpital Necker-Enfants Malades, member of ERN EpiCARE, Paris, France
| | - Nicole Chemaly
- Department of Pediatric Neurology, Reference Center for Rare Epilepsies, Hôpital Necker-Enfants Malades, member of ERN EpiCARE, Paris, France
- Laboratory of Translational Research for Neurological Disorders, INSERM MR1163, Imagine Institute, Paris, France
| | - Catherine Chiron
- Department of Pediatric Neurology, Reference Center for Rare Epilepsies, Hôpital Necker-Enfants Malades, member of ERN EpiCARE, Paris, France
| | - Rima Nabbout
- Department of Pediatric Neurology, Reference Center for Rare Epilepsies, Hôpital Necker-Enfants Malades, member of ERN EpiCARE, Paris, France
- Laboratory of Translational Research for Neurological Disorders, INSERM MR1163, Imagine Institute, Paris, France
- Université de Paris Cité, Paris, France
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Prezioso G, Chiarelli F, Matricardi S. Efficacy and safety of vigabatrin in patients with tuberous sclerosis complex and infantile epileptic spasm syndrome: a systematic review. Expert Rev Neurother 2023; 23:661-671. [PMID: 37243682 DOI: 10.1080/14737175.2023.2216385] [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: 02/14/2023] [Accepted: 05/17/2023] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Tuberous sclerosis complex (TSC) is a common genetic cause of epilepsy. Infantile epileptic spasm syndrome (IESS) is often the presenting neurologic feature, progressively evolving into refractory epilepsy. Vigabatrin (VGB) is often used in clinical practice as a first-line therapy in TSC with IESS. This systematic review aims to collect and analyze the efficacy data about VGB in TSC cases with IESS, in order to evaluate the strength of evidence in the literature. METHODS A systematic search of trials, observational studies, and case series involving patients with TSC and IESS treated with VGB was performed using MEDLINE, CENTRAL, and the US NIH Clinical Trials Registry. Single case studies, animal and non-English language studies were excluded. Seventeen studies were selected, of which 3 were RCTs and 14 were observational studies. RESULTS An overall response rate of 67% (231/343 responders) resulted from the analysis, with a spasm-free rate restricted to RCTs of 88% (29/33 subjects). CONCLUSIONS Although all the studies analyzed reported beneficial effects of VGB in TSC patients with IESS, with higher response rates in comparison to non-TSC subjects with IESS, a low level of evidence and high heterogeneity do not guarantee sufficient strength for therapeutic recommendations.
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Affiliation(s)
- Giovanni Prezioso
- Pediatric Neurologist, Department of Pediatrics, G. D'Annunzio University, Chieti, Italy
| | - Francesco Chiarelli
- Department of Pediatrics, Department of Pediatrics, G. D'Annunzio University, Chieti, Italy
| | - Sara Matricardi
- Pediatric Neurologist, Department of Pediatrics, G. D'Annunzio University, Chieti, Italy
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Takahashi K, Eultgen EM, Wang SH, Rensing NR, Nelvagal HR, Dearborn JT, Danos O, Buss N, Sands MS, Wong M, Cooper JD. Gene therapy ameliorates spontaneous seizures associated with cortical neuron loss in a Cln2R207X mouse model. J Clin Invest 2023; 133:e165908. [PMID: 37104037 PMCID: PMC10266778 DOI: 10.1172/jci165908] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 04/25/2023] [Indexed: 04/28/2023] Open
Abstract
Although a disease-modifying therapy for classic late infantile neuronal ceroid lipofuscinosis (CLN2 disease) exists, poor understanding of cellular pathophysiology has hampered the development of more effective and persistent therapies. Here, we investigated the nature and progression of neurological and underlying neuropathological changes in Cln2R207X mice, which carry one of the most common pathogenic mutations in human patients but are yet to be fully characterized. Long-term electroencephalography recordings revealed progressive epileptiform abnormalities, including spontaneous seizures, providing a robust, quantifiable, and clinically relevant phenotype. These seizures were accompanied by the loss of multiple cortical neuron populations, including those stained for interneuron markers. Further histological analysis revealed early localized microglial activation months before neuron loss started in the thalamocortical system and spinal cord, which was accompanied by astrogliosis. This pathology was more pronounced and occurred in the cortex before the thalamus or spinal cord and differed markedly from the staging seen in mouse models of other forms of neuronal ceroid lipofuscinosis. Neonatal administration of adeno-associated virus serotype 9-mediated gene therapy ameliorated the seizure and gait phenotypes and prolonged the life span of Cln2R207X mice, attenuating most pathological changes. Our findings highlight the importance of clinically relevant outcome measures for judging preclinical efficacy of therapeutic interventions for CLN2 disease.
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Affiliation(s)
| | | | | | | | | | - Joshua T. Dearborn
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | | | - Mark S. Sands
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | - Jonathan D. Cooper
- Department of Pediatrics
- Department of Neurology, and
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
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Hyder Pottoo F, Salahuddin M, Khan FA, Albaqshi BT, Gomaa MS, Abdulla FS, AlHajri N, Alomary MN. Trio-Drug Combination of Sodium Valproate, Baclofen and Thymoquinone Exhibits Synergistic Anticonvulsant Effects in Rats and Neuro-Protective Effects in HEK-293 Cells. Curr Issues Mol Biol 2022; 44:4350-4366. [PMID: 36286014 PMCID: PMC9601194 DOI: 10.3390/cimb44100299] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 10/04/2023] Open
Abstract
Epilepsy is a chronic brain disorder, with anti-epileptic drugs (AEDs) providing relief from hyper-excitability of neurons, but largely failing to restrain neurodegeneration. We investigated a progressive preclinical trial in rats, whereby the test drugs; sodium valproate (SVP; 150 and 300 mg/kg), baclofen (BFN; 5 and 10 mg/kg), and thymoquinone (THQ; 40 and 80 mg/kg) were administered (i.p, once/day for 15 days) alone, and as low dose combinations, and subsequently tested for antiseizure and neuroprotective potential using electrical stimulation of neurons by Maximal electroshock (MES). The seizure stages were monitored, and hippocampal levels of m-TOR, IL-1β, IL-6 were measured. Hippocampal histopathology was also performed. Invitro and Insilco studies were run to counter-confirm the results from rodent studies. We report the synergistic effect of trio-drug combination; SVP (150 mg/kg), BFN (5 mg/kg) and THQ (40 mg/kg) against generalized seizures. The Insilco results revealed that trio-drug combination binds the Akt active site as a supramolecular complex, which could have served as a delivery system that affects the penetration and the binding to the new target. The potential energy of the ternary complex in the Akt active site after dynamics simulation was found to be -370.426 Kcal/mol, while the supramolecular ternary complex alone was -38.732 Kcal/mol, with a potential energy difference of -331.694 Kcal/mol, which favors the supramolecular ternary complex at Akt active site binding. In addition, the said combination increased cell viability by 267% and reduced morphological changes induced by Pentylenetetrazol (PTZ) in HEK-293 cells, which indicates the neuroprotective property of said combination. To conclude, we are the first to report the anti-convulsant and neuroprotective potential of the trio-drug combination.
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Affiliation(s)
- Faheem Hyder Pottoo
- Department of Pharmacology, College of Clinical Pharmacy, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Mohammed Salahuddin
- Department of Clinical Pharmacy Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Firdos Alam Khan
- Department of Stem Cell Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Batool Taleb Albaqshi
- Department of Pharmacology, College of Clinical Pharmacy, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Mohamed S. Gomaa
- Department of Pharmaceutical Chemistry, College of Clinical Pharmacy, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
| | - Fatima S. Abdulla
- College of Medicine and Health Science, Khalifa University, Abu Dhabi P.O. Box 127788, United Arab Emirates
| | - Noora AlHajri
- Department of Medicine, Sheikh Shakhbout Medical City (SSMC), Abu Dhabi P.O. Box 127788, United Arab Emirates
| | - Mohammad N. Alomary
- National Centre for Biotechnology, Kind Abdulaziz City for Science and Technology (KACST), Riyadh 11442, Saudi Arabia
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Sadowski K, Sijko K, Domańska-Pakieła D, Borkowska J, Chmielewski D, Ulatowska A, Józwiak S, Kotulska K. Antiepileptic Effect and Safety Profile of Rapamycin in Pediatric Patients With Tuberous Sclerosis Complex. Front Neurol 2022; 13:704978. [PMID: 35572924 PMCID: PMC9100395 DOI: 10.3389/fneur.2022.704978] [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: 05/04/2021] [Accepted: 02/04/2022] [Indexed: 11/25/2022] Open
Abstract
Background Epilepsy develops in 70–90% of children with Tuberous Sclerosis Complex (TSC) and is often resistant to medication. Treatment with mTOR pathway inhibitors is an important therapeutic option in drug-resistant epilepsy associated with TSC. Our study evaluated the antiepileptic effect of rapamycin in the pediatric population of patients diagnosed with TSC. Methods This single center, open-label study evaluated safety and anti-epileptic efficacy of 12 months of rapamycin treatment in 32 patients aged from 11 months to 14 years with drug-resistant TSC- associated epilepsy. Results After the first 6 months of treatment, the improvement in seizure frequency, defined as at least a 50% reduction in the number of seizures per week compared to baseline, was seen in 18 individuals (56.25%). We observed no change in 12 individuals (37.5%) and worsening, defined as increase in the number of seizures—in 2 patients (6.25%). The overall improvement defined as at least a 50% reduction in seizure frequency was found in 65.6% of all patients after 12 months with 28% of patients obtaining complete remission. Another five patients experienced at least an 80% reduction in the frequency of seizures. Concomitant treatment with vigabatrin, and to a much lesser extent topiramate and levetiracetam, was an additional favorable prognostic factor for the success of the therapy. A linear relationship between the cumulative dose of rapamycin and its therapeutic effect was observed. The safety profile of the drug was satisfactory. In none of the observed cases did the adverse events reach the level that required withdrawal of the rapamycin treatment. The reason for dropouts was insufficient drug efficacy in 3 cases. Conclusions Long-term use of rapamycin, especially in combination with vigabatrin, might be a beneficial therapeutic option in the treatment of drug-resistant epilepsy in children with TSC.
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Affiliation(s)
- Krzysztof Sadowski
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
- *Correspondence: Krzysztof Sadowski
| | - Kamil Sijko
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
- Transition Technologies, Warsaw, Poland
| | - Dorota Domańska-Pakieła
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Julita Borkowska
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Dariusz Chmielewski
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Agata Ulatowska
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Sergiusz Józwiak
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
- Department of Child Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
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Rare Neurological Diseases: an Overreview of Pathophysiology, Epidemiology, Clinical Features and Pharmacoeconomic Considerations in the Treating. SERBIAN JOURNAL OF EXPERIMENTAL AND CLINICAL RESEARCH 2021. [DOI: 10.2478/sjecr-2021-0049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Rare diseases (RD) are serious chronic diseases affecting small number of people compared to the general population. There are between 6000 and 8000 RDs, which affect about 400 million people worldwide. Drugs used for causal treatment of RDs are called orphan drugs. RDs bear great clinical and economic burden for patients, their families, healthcare systems and society overall. There are at least two reasons for the high cost of treatment of RDs. First, there is no causal therapy for majority of RDs, so exacerbations, complications, and hospitalizations in those patients are common. The second reason is high price of available orphan drugs, which are not cost-effective when traditional pharmacoeconomic evaluation is employed. The pharmacoeconomic aspect of the treatment of RDs is especially important in the field of neurology, since at least one fifth of all RDs is composed of neurological conditions. The aim of this paper was to provide a concise overview of the pathophysiological, epidemiological and clinical characteristics of some of the most important and common rare neurological diseases, with special reference to their impact on society and economy.
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Byrne S, Enright N, Delanty N. Precision therapy in the genetic epilepsies of childhood. Dev Med Child Neurol 2021; 63:1276-1282. [PMID: 34089185 DOI: 10.1111/dmcn.14929] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/16/2021] [Indexed: 12/18/2022]
Abstract
Despite recent advances in both the understanding and treatment of the epilepsies, the rate of refractory epilepsy has remained static for many years. However, given our greater understanding of the aetiology and genetic basis of many paediatric and adult epilepsies, there is now scope to expand treatment. In this review, we discuss the current and potential use of precision medicine in the genetic epilepsies of childhood. We will discuss how optimal control and a reduction in the rate of refractory seizures using targeted therapy could be developed and assessed. We propose a six-tier approach to defining precision therapeutics in epilepsy and discuss how this can be incorporated into a clinical trial design. The lower tiers (1-2) represent therapies in common usage that we know work for certain epilepsy syndromes but do not precisely target the underlying problem. They work to reduce seizures but do not directly or effectively attenuate the developmental phenotype. The higher tiers (5-6) are currently purely speculative and look to a future with highly disease-specific therapies based on correction of underlying genomic and proteomic issues. In order to achieve this, scientists will have to embark on a 'whole-omic' approach to understand the underlying pathophysiology in order to design a precision therapy. What this paper adds Epilepsy treatment is classified into six tiers depending on how precisely the mechanism of action addresses the aetiology. Tier 1 treatment is based on the historical response of certain epilepsy phenotypes to specific medication. Tier 6 concerns therapy targeting genes and networks that rescue the whole phenotype. Clinical trial infrastructure and population-based disease registries are necessary so that patients can participate in trials for novel precision therapies.
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Affiliation(s)
- Susan Byrne
- FutureNeuro SFI Research Centre and Department of Paediatrics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Paediatric Neurology, CHI at Crumlin, Dublin, Ireland
| | - Noelle Enright
- FutureNeuro SFI Research Centre and Department of Paediatrics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Paediatric Neurology, Great Ormond Street Hospital, London, UK
| | - Norman Delanty
- FutureNeuro SFI Research Centre and Department of Paediatrics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Neurology, Beaumont Hospital, Dublin, Ireland
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13
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Synaptic Alterations in a Transgenic Model of Tuberous Sclerosis Complex: Relevance to Autism Spectrum Disorders. Int J Mol Sci 2021; 22:ijms221810058. [PMID: 34576223 PMCID: PMC8466868 DOI: 10.3390/ijms221810058] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/08/2021] [Accepted: 09/14/2021] [Indexed: 01/02/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is a rare, multi-system genetic disease with serious neurological and mental symptoms, including autism. Mutations in the TSC1/TSC2 genes lead to the overactivation of mTOR signalling, which is also linked to nonsyndromic autism. Our aim was to analyse synaptic pathology in a transgenic model of TSC: two-month-old male B6;129S4-Tsc2tm1Djk/J mice with Tsc2 haploinsufficiency. Significant brain-region-dependent alterations in the expression of several synaptic proteins were identified. The most prominent changes were observed in the immunoreactivity of presynaptic VAMP1/2 (ca. 50% increase) and phospho-synapsin-1 (Ser62/67) (ca. 80% increase). Transmission electron microscopy demonstrated serious ultrastructural abnormalities in synapses such as a blurred structure of synaptic density and a significantly increased number of synaptic vesicles. The impairment of synaptic mitochondrial ultrastructure was represented by excessive elongation, swelling, and blurred crista contours. Polyribosomes in the cytoplasm and swollen Golgi apparatus suggest possible impairment of protein metabolism. Moreover, the delamination of myelin and the presence of vacuolar structures in the cell nucleus were observed. We also report that Tsc2+/- mice displayed increased brain weights and sizes. The behavioural analysis demonstrated the impairment of memory function, as established in the novel object recognition test. To summarise, our data indicate serious synaptic impairment in the brains of male Tsc2+/- mice.
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14
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Nabbout R, Kuchenbuch M, Chiron C, Curatolo P. Pharmacotherapy for Seizures in Tuberous Sclerosis Complex. CNS Drugs 2021; 35:965-983. [PMID: 34417984 DOI: 10.1007/s40263-021-00835-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/05/2021] [Indexed: 01/18/2023]
Abstract
Epilepsy is one of the main symptoms affecting the lives of individuals with tuberous sclerosis complex (TSC), causing a high rate of morbidity. Individuals with TSC can present with various types of seizures, epilepsies, and epilepsy syndromes that can coexist or appear in relation to age. Focal epilepsy is the most frequent epilepsy type with two developmental and epileptic encephalopathies: infantile spasms syndrome and Lennox-Gastaut syndrome. Active screening and early management of epilepsy is recommended in individuals with TSC to limit its consequences and its impact on quality of life, cognitive outcome and the economic burden of the disease. The progress in the knowledge of the mechanisms underlying epilepsy in TSC has paved the way for new concepts in the management of epilepsy related to TSC. In addition, we are moving from traditional "reactive" and therapeutic choices with current antiseizure medications used after the onset of seizures, to a proactive approach, aimed at predicting and preventing epileptogenesis and the onset of epilepsy with vigabatrin, and to personalized treatments with mechanistic therapies, namely mechanistic/mammalian target of rapamycin inhibitors. Indeed, epilepsy linked to TSC is one of the only epilepsies for which a predictive and preventive approach can delay seizure onset and improve seizure response. However, the efficacy of such interventions on long-term cognitive and psychiatric outcomes is still under investigation.
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Affiliation(s)
- Rima Nabbout
- Reference Centre for Rare Epilepsies, Department of Pediatric Neurology, Necker Enfants Malades University Hospital, APHP, Université de Paris, 149 rue de Sèvres, 75015, Paris, France.
- UMR 1163, Institut National de la Santé et de la Recherche Médicale (INSERM), Imagine Institute, Université de Paris, Paris, France.
| | - Mathieu Kuchenbuch
- Reference Centre for Rare Epilepsies, Department of Pediatric Neurology, Necker Enfants Malades University Hospital, APHP, Université de Paris, 149 rue de Sèvres, 75015, Paris, France
- UMR 1163, Institut National de la Santé et de la Recherche Médicale (INSERM), Imagine Institute, Université de Paris, Paris, France
| | - Catherine Chiron
- Reference Centre for Rare Epilepsies, Department of Pediatric Neurology, Necker Enfants Malades University Hospital, APHP, Université de Paris, 149 rue de Sèvres, 75015, Paris, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR 1141, Neurospin, Gif sur Yvette, France
| | - Paolo Curatolo
- Department of System Medicine, Child Neurology and Psychiatry Unit, Tor Vergata University Hospital, Rome, Italy
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15
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Bassetti D, Luhmann HJ, Kirischuk S. Effects of Mutations in TSC Genes on Neurodevelopment and Synaptic Transmission. Int J Mol Sci 2021; 22:ijms22147273. [PMID: 34298906 PMCID: PMC8305053 DOI: 10.3390/ijms22147273] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/02/2021] [Accepted: 07/04/2021] [Indexed: 12/11/2022] Open
Abstract
Mutations in TSC1 or TSC2 genes are linked to alterations in neuronal function which ultimately lead to the development of a complex neurological phenotype. Here we review current research on the effects that reduction in TSC1 or TSC2 can produce on the developing neural network. A crucial feature of the disease pathophysiology appears to be an early deviation from typical neurodevelopment, in the form of structural abnormalities. Epileptic seizures are one of the primary early manifestation of the disease in the CNS, followed by intellectual deficits and autism spectrum disorders (ASD). Research using mouse models suggests that morphological brain alterations might arise from the interaction of different cellular types, and hyperexcitability in the early postnatal period might be transient. Moreover, the increased excitation-to-inhibition ratio might represent a transient compensatory adjustment to stabilize the developing network rather than a primary factor for the development of ASD symptoms. The inhomogeneous results suggest region-specificity as well as an evolving picture of functional alterations along development. Furthermore, ASD symptoms and epilepsy might originate from different but potentially overlapping mechanisms, which can explain recent observations obtained in patients. Potential treatment is determined not only by the type of medicament, but also by the time point of treatment.
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16
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D'Gama AM, Poduri A. Precision Therapy for Epilepsy Related to Brain Malformations. Neurotherapeutics 2021; 18:1548-1563. [PMID: 34608615 PMCID: PMC8608994 DOI: 10.1007/s13311-021-01122-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2021] [Indexed: 02/04/2023] Open
Abstract
Malformations of cortical development (MCDs) represent a range of neurodevelopmental disorders that are collectively common causes of developmental delay and epilepsy, especially refractory childhood epilepsy. Initial treatment with antiseizure medications is empiric, and consideration of surgery is the standard of care for eligible patients with medically refractory epilepsy. In the past decade, advances in next generation sequencing technologies have accelerated progress in understanding the genetic etiologies of MCDs, and precision therapies for focal MCDs are emerging. Notably, mutations that lead to abnormal activation of the mammalian target of rapamycin (mTOR) pathway, which provides critical control of cell growth and proliferation, have emerged as a common cause of malformations. These include tuberous sclerosis complex (TSC), hemimegalencephaly (HME), and some types of focal cortical dysplasia (FCD). TSC currently represents the best example for the pathway from gene discovery to relatively safe and efficacious targeted therapy for epilepsy related to MCDs. Based on extensive pre-clinical and clinical data, the mTOR inhibitor everolimus is currently approved for the treatment of focal refractory seizures in patients with TSC. Although clinical studies are just emerging for FCD and HME, we believe the next decade will bring significant advancements in precision therapies for epilepsy related to these and other MCDs.
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Affiliation(s)
- Alissa M D'Gama
- Divisions of Newborn Medicine and Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
- Departments of Neurology and Pediatrics, Harvard Medical School, Boston, MA, USA
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Annapurna Poduri
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA.
- Departments of Neurology and Pediatrics, Harvard Medical School, Boston, MA, USA.
- Broad Institute of Harvard and MIT, Cambridge, MA, USA.
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17
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Armstrong C, Marsh ED. Electrophysiological Biomarkers in Genetic Epilepsies. Neurotherapeutics 2021; 18:1458-1467. [PMID: 34642905 PMCID: PMC8609056 DOI: 10.1007/s13311-021-01132-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2021] [Indexed: 02/04/2023] Open
Abstract
Precision treatments for epilepsy targeting the underlying genetic diagnoses are becoming a reality. Historically, the goal of epilepsy treatments was to reduce seizure frequency. In the era of precision medicine, however, outcomes such as prevention of epilepsy progression or even improvements in cognitive functions are both aspirational targets for any intervention. Developing methods, both in clinical trial design and in novel endpoints, will be necessary for measuring, not only seizures, but also the other neurodevelopmental outcomes that are predicted to be targeted by precision treatments. Biomarkers that quantitatively measure disease progression or network level changes are needed to allow for unbiased measurements of the effects of any gene-level treatments. Here, we discuss some of the promising electrophysiological biomarkers that may be of use in clinical trials of precision therapies, as well as the difficulties in implementing them.
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Affiliation(s)
- Caren Armstrong
- Division of Neurology and Pediatric Epilepsy Program, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - Eric D Marsh
- Division of Neurology and Pediatric Epilepsy Program, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
- Department of Pediatrics and Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA.
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18
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UYSAL SP, ŞAHİN M. Tuberous sclerosis: a review of the past, present, and future. Turk J Med Sci 2020; 50:1665-1676. [PMID: 32222129 PMCID: PMC7672342 DOI: 10.3906/sag-2002-133] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/22/2020] [Indexed: 11/23/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant, multisystem disorder that is characterized by cellular and tissue dysplasia in several organs. With the advent of genetic and molecular techniques, mutations in the TSC1 or TSC2 genes were discovered to be responsible for mTOR overactivation, which is the underlying mechanism of pathogenesis. TSC is a highly heterogenous clinical entity with variable presentations and severity of disease. The brain, heart, skin, eyes, kidneys, and lungs are commonly involved in this syndrome, with neurologic symptoms comprising a significant source of morbidity and mortality. In 2012, the diagnostic criteria for TSC were revised by the International Tuberous Sclerosis Complex Consensus panel, and genetic testing was incorporated into the guidelines. Early detection of cardiac rhabdomyomas or TSC-associated skin lesions can suggest the diagnosis and underlie the importance of clinical vigilance. Animal studies have demonstrated the benefit of using mTOR inhibitors for various symptoms of TSC, and they have been successfully translated into clinical trials with significant improvement in symptom burden. Subependymal giant cell astrocytomas, renal angiomyolipomas, and epilepsy are the three FDA-approved indications in relation to TSC for the use of everolimus, which is a first generation mTOR inhibitor. Rapamycin has been FDA approved for lymphangioleiomyomatosis. Other TSC symptoms that could potentially benefit from this class of medication are currently under investigation. TSC constitutes a unique combination of protean physical symptoms and neurobehavioral abnormalities. TSC associated neuropsychiatric disorders (TAND), including intellectual disability, mood disorders, and autism spectrum disorder, represent significant challenges but remain underdiagnosed and undertreated. The TAND checklist is a useful tool for routine use in the clinical evaluation of TSC patients. A multidisciplinary treatment plan, based on the specific problems and needs of individuals, is the key to management of this genetic condition. Ongoing research studies have been providing promising leads for developing novel mechanistic strategies to address the pathophysiology of TSC.
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Affiliation(s)
- Sanem Pınar UYSAL
- Department of Neurology, Harvard Medical School, Boston Children’s Hospital, Boston MassachusettsUSA
| | - Mustafa ŞAHİN
- Department of Neurology, Harvard Medical School, Boston Children’s Hospital, Boston MassachusettsUSA
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19
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Zimmer TS, Broekaart DWM, Gruber VE, van Vliet EA, Mühlebner A, Aronica E. Tuberous Sclerosis Complex as Disease Model for Investigating mTOR-Related Gliopathy During Epileptogenesis. Front Neurol 2020; 11:1028. [PMID: 33041976 PMCID: PMC7527496 DOI: 10.3389/fneur.2020.01028] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
Tuberous sclerosis complex (TSC) represents the prototypic monogenic disorder of the mammalian target of rapamycin (mTOR) pathway dysregulation. It provides the rational mechanistic basis of a direct link between gene mutation and brain pathology (structural and functional abnormalities) associated with a complex clinical phenotype including epilepsy, autism, and intellectual disability. So far, research conducted in TSC has been largely neuron-oriented. However, the neuropathological hallmarks of TSC and other malformations of cortical development also include major morphological and functional changes in glial cells involving astrocytes, oligodendrocytes, NG2 glia, and microglia. These cells and their interglial crosstalk may offer new insights into the common neurobiological mechanisms underlying epilepsy and the complex cognitive and behavioral comorbidities that are characteristic of the spectrum of mTOR-associated neurodevelopmental disorders. This review will focus on the role of glial dysfunction, the interaction between glia related to mTOR hyperactivity, and its contribution to epileptogenesis in TSC. Moreover, we will discuss how understanding glial abnormalities in TSC might give valuable insight into the pathophysiological mechanisms that could help to develop novel therapeutic approaches for TSC or other pathologies characterized by glial dysfunction and acquired mTOR hyperactivation.
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Affiliation(s)
- Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Diede W M Broekaart
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | | | - Erwin A van Vliet
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
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20
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Kats DJ, Roche KJ, Skotko BG. Epileptic spasms in individuals with Down syndrome: A review of the current literature. Epilepsia Open 2020; 5:344-353. [PMID: 32913943 PMCID: PMC7469826 DOI: 10.1002/epi4.12412] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/27/2020] [Accepted: 06/03/2020] [Indexed: 02/06/2023] Open
Abstract
Epilepsy can occur in individuals with Down syndrome (DS), with epileptic spasms representing the most frequent seizure type in this population. Epileptic spasms can have devastating consequences on the development of individuals with the condition. This review sought to explore the lifetime prevalence and underlying mechanism of epileptic spasms in this population. We also aimed to review the response rate to various treatments, the relapse rate, and the development of subsequent epilepsy or autism in this population. A comprehensive literature search was conducted for articles discussing the lifetime prevalence, diagnosis, treatment, outcomes, or underlying etiology of epileptic spasms in animal models or individuals with DS. According to available literature, the global clinic-based lifetime prevalence of epilepsy in individuals with DS ranged from 1.6% to 23.1%, with epileptic spasms representing 6.7%-66.7% of these cases. Response rate to treatment with adrenocorticotropic hormone/corticosteroids was highest (81%) and has the most literature supporting its use, with other regimens, including vigabatrin and other antiepileptic drugs, having lower response rates. Epileptic spasms occur more frequently in children with DS than in the general population, though more studies are needed to determine the true lifetime prevalence of epileptic spasms in this population. Generally, children with DS and epileptic spasms tend to be more responsive to treatment and have better outcomes than children with epileptic spasms of unknown etiology (ie, without DS), in terms of response and relapse rates as well as the development of intractable epilepsy (eg, Lennox-Gastaut syndrome).
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Affiliation(s)
- Daniel J. Kats
- Case Western Reserve University School of MedicineClevelandOHUSA
- Down Syndrome ProgramDivision of Medical Genetics and MetabolismDepartment of PediatricsMassachusetts General HospitalBostonMAUSA
| | - Katherine J. Roche
- Department of PediatricsHarvard Medical SchoolBostonMAUSA
- Harvard‐MIT Division of Health Sciences and TechnologyCambridgeMAUSA
| | - Brian G. Skotko
- Down Syndrome ProgramDivision of Medical Genetics and MetabolismDepartment of PediatricsMassachusetts General HospitalBostonMAUSA
- Department of PediatricsHarvard Medical SchoolBostonMAUSA
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21
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Abstract
Children with infantile spasms are likely to have a poor outcome. Outcome measures for infantile spasms include primary response to treatment, relapse of spasms, neurological development, death, and progression to another type of epilepsy (Consensus Statements of the WEST Delphi Group 2004). This review is based mainly on prospective studies and emphasizes data about the current first-line drugs, adrenocorticotropic hormone, vigabatrin, and prednisolone, taking into account the proportion of patients with known and unknown etiology, which has a very strong effect on seizure outcome. In most studies, hormonal treatment (adrenocorticotropic hormone or prednisolone) is the optimal monotherapy, except for patients with tuberous sclerosis complex, in whom vigabatrin appears superior. Combination therapy (hormones plus vigabatrin) may well be more effective than either agent alone. The underlying etiology is the most important prognostic factor. In studies with a long follow-up (up to 50 years), a favorable cognitive outcome has been observed in approximately one quarter of patients and complete seizure freedom in one-third. Autism is relatively frequent, and premature mortality is high throughout life. Modifiable prognostic factors include early recognition of the spasms with prompt treatment, short duration of hypsarrhythmia, prompt treatment of relapses of spasms and multifocal epileptic discharges, and early treatment of adverse effects. It is hoped that eventually advanced genetics and molecular data will allow an understanding of the pathogenetic mechanisms of many specific etiologies to allow disease-specific treatment such as is emerging for tuberous sclerosis.
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Affiliation(s)
- Raili Riikonen
- Children's Hospital, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland.
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22
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Specchio N, Pietrafusa N, Ferretti A, De Palma L, Santarone ME, Pepi C, Trivisano M, Vigevano F, Curatolo P. Treatment of infantile spasms: why do we know so little? Expert Rev Neurother 2020; 20:551-566. [PMID: 32316776 DOI: 10.1080/14737175.2020.1759423] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Infantile spasm (IS) is an epileptic syndrome with typical onset within the first 2 years of life. This condition might be caused by several etiologies. IS is associated with pathological neuronal networks; however, definite hypotheses on neurobiological processes are awaited. AREAS COVERED Changes in NMDA and GABAB receptors and increase of Ca2+ conductance are some of the possible pathophysiological mechanisms. Animal models can help, but most have only some features of IS. Outcome is strongly affected by etiology and the timing of treatment, which relies still on ACTH, oral steroids, and vigabatrin. No significant differences in terms of efficacy have been documented, though a combination of ACTH and vigabatrin seems to be associated with better long-term outcomes. Despite the increasing knowledge about the etiology and pathophysiology of IS, in the last years, no new treatment approaches have been recognized to be able to modify the neurobiological process underlying IS. Precision medicine has far to come in IS. EXPERT OPINION Recently, no new therapeutic options for IS have emerged, probably due to the lack of reliable animal models and to the extreme variability in etiologies. Consequently, the outlook for patients and families is poor and early recognition and intervention remain research priorities.
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Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy.,Member of European Reference Network EpiCARE
| | - Nicola Pietrafusa
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy
| | - Alessandro Ferretti
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy
| | - Luca De Palma
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy
| | - Marta Elena Santarone
- Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , 00165, Rome, Italy
| | - Chiara Pepi
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy.,Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University , 00133, Rome, Italy
| | - Marina Trivisano
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , Rome, 00165, Italy
| | - Federico Vigevano
- Member of European Reference Network EpiCARE.,Department of Neuroscience, Bambino Gesù Children's Hospital, IRCCS , 00165, Rome, Italy
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University , 00133, Rome, Italy
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23
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Rensing N, Johnson KJ, Foutz TJ, Friedman JL, Galindo R, Wong M. Early developmental electroencephalography abnormalities, neonatal seizures, and induced spasms in a mouse model of tuberous sclerosis complex. Epilepsia 2020; 61:879-891. [PMID: 32274803 DOI: 10.1111/epi.16495] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/10/2020] [Accepted: 03/11/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Tuberous sclerosis complex (TSC) is one of the most common genetic causes of epilepsy. Seizures in TSC typically first present in infancy or early childhood, including focal seizures and infantile spasms. Infantile spasms in TSC are particularly characteristic in its strong responsiveness to vigabatrin. Although a number of mouse models of epilepsy in TSC have been described, there are very limited electroencephalographic (EEG) or seizure data during the preweanling neonatal and infantile-equivalent mouse periods. Tsc1GFAP CKO mice are a well-characterized mouse model of epilepsy in TSC, but whether these mice have seizures during early development has not been documented. The objective of this study was to determine whether preweanling Tsc1GFAP CKO mice have developmental EEG abnormalities or seizures, including spasms. METHODS Longitudinal video-EEG and electromyographic recordings were performed serially on Tsc1GFAP CKO and control mice from postnatal days 9-21 and analyzed for EEG background abnormalities, sleep-wake vigilance states, and spontaneous seizures. Spasms were also induced with varying doses of N-methyl-D-aspartate (NMDA). RESULTS The interictal EEG of Tsc1GFAP CKO mice had excessive discontinuity and slowing, suggesting a delayed developmental progression compared with control mice. Tsc1GFAP CKO mice also had increased vigilance state transitions and fragmentation. Tsc1GFAP CKO mice had spontaneous focal seizures in the early neonatal period and a reduced threshold for NMDA-induced spasms, but no spontaneous spasms were observed. SIGNIFICANCE Neonatal Tsc1GFAP CKO mice recapitulate early developmental aspects of EEG abnormalities, focal seizures, and an increased propensity for spasms. This mouse model may be useful for early mechanistic and therapeutic studies of epileptogenesis in TSC.
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Affiliation(s)
- Nicholas Rensing
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
| | - Kevin J Johnson
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
| | - Thomas J Foutz
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
| | - Joseph L Friedman
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
| | - Rafael Galindo
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
| | - Michael Wong
- Department of Neurology and Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri
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24
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Klein P, Friedman A, Hameed MQ, Kaminski RM, Bar-Klein G, Klitgaard H, Koepp M, Jozwiak S, Prince DA, Rotenberg A, Twyman R, Vezzani A, Wong M, Löscher W. Repurposed molecules for antiepileptogenesis: Missing an opportunity to prevent epilepsy? Epilepsia 2020; 61:359-386. [PMID: 32196665 PMCID: PMC8317585 DOI: 10.1111/epi.16450] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/26/2020] [Accepted: 01/27/2020] [Indexed: 12/11/2022]
Abstract
Prevention of epilepsy is a great unmet need. Acute central nervous system (CNS) insults such as traumatic brain injury (TBI), cerebrovascular accidents (CVA), and CNS infections account for 15%-20% of all epilepsy. Following TBI and CVA, there is a latency of days to years before epilepsy develops. This allows treatment to prevent or modify postinjury epilepsy. No such treatment exists. In animal models of acquired epilepsy, a number of medications in clinical use for diverse indications have been shown to have antiepileptogenic or disease-modifying effects, including medications with excellent side effect profiles. These include atorvastatin, ceftriaxone, losartan, isoflurane, N-acetylcysteine, and the antiseizure medications levetiracetam, brivaracetam, topiramate, gabapentin, pregabalin, vigabatrin, and eslicarbazepine acetate. In addition, there are preclinical antiepileptogenic data for anakinra, rapamycin, fingolimod, and erythropoietin, although these medications have potential for more serious side effects. However, except for vigabatrin, there have been almost no translation studies to prevent or modify epilepsy using these potentially "repurposable" medications. We may be missing an opportunity to develop preventive treatment for epilepsy by not evaluating these medications clinically. One reason for the lack of translation studies is that the preclinical data for most of these medications are disparate in terms of types of injury, models within different injury type, dosing, injury-treatment initiation latencies, treatment duration, and epilepsy outcome evaluation mode and duration. This makes it difficult to compare the relative strength of antiepileptogenic evidence across the molecules, and difficult to determine which drug(s) would be the best to evaluate clinically. Furthermore, most preclinical antiepileptogenic studies lack information needed for translation, such as dose-blood level relationship, brain target engagement, and dose-response, and many use treatment parameters that cannot be applied clinically, for example, treatment initiation before or at the time of injury and dosing higher than tolerated human equivalent dosing. Here, we review animal and human antiepileptogenic evidence for these medications. We highlight the gaps in our knowledge for each molecule that need to be filled in order to consider clinical translation, and we suggest a platform of preclinical antiepileptogenesis evaluation of potentially repurposable molecules or their combinations going forward.
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Affiliation(s)
- Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, Maryland
| | - Alon Friedman
- Departments of Physiology and Cell Biology, and Brain and Cognitive Science, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Departments of Medical Neuroscience and Brain Repair Center, Dalhousie University, Halifax, Canada
| | - Mustafa Q. Hameed
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Rafal M. Kaminski
- Neurosymptomatic Domains Section, Roche Pharma Research & Early Development, Roche Innovation Center, Basel, Switzerland
| | - Guy Bar-Klein
- McKusick-Nathans Institute of Genetic Medicine, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Henrik Klitgaard
- Neurosciences Therapeutic Area, UCB Pharma, Braine-l’Alleud, Belgium
| | - Mathias Koepp
- Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, London, UK
| | - Sergiusz Jozwiak
- Department of Pediatric Neurology, Warsaw Medical University, Warsaw, Poland
| | - David A. Prince
- Neurology and the Neurological Sciences, Stanford University School of Medicine, Stanford, California
| | - Alexander Rotenberg
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Annamaria Vezzani
- Department of Neuroscience, Mario Negri Institute for Pharmacological Research, Scientific Institute for Research and Health Care, Milan, Italy
| | - Michael Wong
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
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Świąder MJ, Świąder K, Zakrocka I, Krzyżanowski M, Wróbel A, Łuszczki JJ, Czuczwar SJ. Long-term vigabatrin treatment modifies pentylenetetrazole-induced seizures in mice: focused on GABA brain concentration. Pharmacol Rep 2020; 72:322-330. [PMID: 32048251 DOI: 10.1007/s43440-019-00037-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/24/2019] [Accepted: 10/11/2019] [Indexed: 01/08/2023]
Abstract
BACKGROUND The goal of our study was to examine the long-term effect of vigabatrin (VGB), a γ-aminobutyric acid aminotransferase (GABA-AT) inhibitor on clonazepam (CLO), ethosuximide (ETX) and valproate (VPA) anticonvulsive activity against pentylenetetrazole (PTZ)-induced seizures in mice. METHODS VGB was administered for 3 and 7 days. Convulsions were evoked by PTZ at its CD97 (99 mg/kg). The influence of CLO, ETX and VPA alone or in combination with VGB on motor performance and long-term memory was analyzed. γ-aminobutyric acid (GABA) concentration in mice brain and plasma as well as glutamate decarboxylase (GAD) activity was measured. RESULTS After 3 days of treatment, VGB in doses up to 500 mg/kg increased PTZ-induced seizure threshold, whereas after 7 days VGB (at the dose of 125 mg/kg) inhibited clonic seizures in experimental mice. 7 days of VGB administration did not change the protective effect of CLO, ETX and VPA against PTZ-induced seizures. 7 days of VGB treatment at a subthreshold dose of 75 mg/kg decreased TD50 of ETX and CLO in the chimney test, but did not affect TD50 value for VPA. 7 days of VGB administration in combination with AEDs did not affect long-term memory in mice. VGB after 3 days or 7 days of administration increased brain GABA concentration. GAD activity was decreased after 3 and 7 days of VGB administration. CONCLUSIONS The presented results confirm anticonvulsive activity of VGB through GABA metabolism alteration and suggest care when combining VGB with ETX or CLO in the therapy.
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Affiliation(s)
- Mariusz J Świąder
- Department of Experimental and Clinical Pharmacology, Collegium Pathologicum, Medical University of Lublin, ul. Jaczewskiego 8b, 20-090, Lublin, Poland.
| | - Katarzyna Świąder
- Department of Applied Pharmacy, Medical University of Lublin, ul. Chodźki 1, 20-093, Lublin, Poland
| | - Izabela Zakrocka
- Department of Nephrology, Medical University of Lublin, ul. Jaczewskiego 8, 20-090, Lublin, Poland
| | - Maciej Krzyżanowski
- Department of Pathophysiology, Medical University of Lublin, ul. Jaczewskiego 8b, 20-090, Lublin, Poland
| | - Andrzej Wróbel
- 2nd Department of Gynecology, Medical University of Lublin, ul. Jaczewskiego 8, 20-090, Lublin, Poland
| | - Jarogniew J Łuszczki
- Department of Pathophysiology, Medical University of Lublin, ul. Jaczewskiego 8b, 20-090, Lublin, Poland
| | - Stanisław J Czuczwar
- Department of Pathophysiology, Medical University of Lublin, ul. Jaczewskiego 8b, 20-090, Lublin, Poland
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Khan AU, Akram M, Daniyal M, Akhter N, Riaz M, Akhtar N, Shariati MA, Anjum F, Khan SG, Parveen A, Ahmad S. Awareness and current knowledge of epilepsy. Metab Brain Dis 2020; 35:45-63. [PMID: 31605258 DOI: 10.1007/s11011-019-00494-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 09/12/2019] [Indexed: 12/29/2022]
Abstract
Epilepsy is a severe neural disorder that affects approximately fifty million individuals globally. Despite the fact that for most of the people with epilepsy, convulsions are better controlled by current accessible antiepileptic medicines, yet there are more than 30% of individuals affected with medically intractable epilepsy and around 30-40% of all patients with epilepsy affected by many adverse reactions and convulsion resistance to the present antiepileptic drugs. Consequently, various scientists attempt to develop new strategies to treat epilepsy, for instance, to find out novel antiepileptic ingredients from traditional medicines. This work aims to present a complete summary of natural medicines prescribed as antiepileptic agents all over the world by ethnic groups and different tribes. We undertook an extensive bibliographic analysis by searching peer reviewed papers and classical textbooks and further consulting well accepted worldwide scientific databases. We carried out PubMed, EMbase and CENTRAL searches by means of terms such as "antiepileptic" and "anti-convulsant" activity of plants. Medicinal plants have been prescribed to treat epilepsy and have been recognized as antiepileptic medicines. In this review, a variety of herbs have been reviewed for thorough studies such as Cuminum cyminum, Butea monosperma, Solanum americanum, Anacyclus pyrethrum, Leonotis leonurus, Elaeocarpus ganitrus and Angelica archangelica. This paper shows that it was high time experimental studies are increased to obtain novel potential active principles from medicinal plants. Plant extracts and their chemical constituents should be further evaluated to clarify their mechanisms of action. This paper provides a solid base upon which to further investigate the clinical efficacy of medicinal plants that are both currently prescribed by physicians as traditional antiepileptic agents, but also could be effective as an antiepileptic drug with further research and study.
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Affiliation(s)
- Asmat Ullah Khan
- Department of Eastern Medicine, The University of Poonch, Rawalakot, Azad Jammu and Kashmir, Pakistan
| | - Muhammad Akram
- Department of Eastern Medicine, Government College University, Faisalabad, Pakistan
| | - Muhammad Daniyal
- TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Materia Medica Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, China
| | - Naheed Akhter
- College of Allied Health Professional, Government College University, Faisalabad, Pakistan
| | - Muhammad Riaz
- Department of Allied Health Sciences, Sargodha Medical College, University of Sargodha, Sargodha, Pakistan
| | - Naheed Akhtar
- Department of Pharmacy, The University of Poonch, Rawalakot, Azad Jammu and Kashmir, Pakistan
| | - Mohammad Ali Shariati
- Kazakh Research Institute of Processing and Food industry (Semey branch), Semey, Kazakhstan
| | - Fozia Anjum
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - Samreen Gul Khan
- Department of Chemistry, Government College University, Faisalabad, Pakistan
| | - Abida Parveen
- Department of Botany, Government College University, Faisalabad, Pakistan
| | - Saeed Ahmad
- University College of Agriculture, University of Sargodha, Sargodha, Pakistan.
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Shen J, Wang C, Ying J, Xu T, McAlinden A, O’Keefe RJ. Inhibition of 4-aminobutyrate aminotransferase protects against injury-induced osteoarthritis in mice. JCI Insight 2019; 4:128568. [PMID: 31534049 PMCID: PMC6795381 DOI: 10.1172/jci.insight.128568] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 08/08/2019] [Indexed: 11/17/2022] Open
Abstract
Recently we demonstrated that ablation of the DNA methyltransferase enzyme, Dnmt3b, resulted in catabolism and progression of osteoarthritis (OA) in murine articular cartilage through a mechanism involving increased mitochondrial respiration. In this study, we identify 4-aminobutyrate aminotransferase (Abat) as a downstream target of Dnmt3b. Abat is an enzyme that metabolizes γ-aminobutyric acid to succinate, a key intermediate in the tricarboxylic acid cycle. We show that Dnmt3b binds to the Abat promoter, increases methylation of a conserved CpG sequence just upstream of the transcriptional start site, and inhibits Abat expression. Dnmt3b deletion in articular chondrocytes results in reduced methylation of the CpG sequence in the Abat promoter, which subsequently increases expression of Abat. Increased Abat expression in chondrocytes leads to enhanced mitochondrial respiration and elevated expression of catabolic genes. Overexpression of Abat in murine knee joints via lentiviral injection results in accelerated cartilage degradation following surgical induction of OA. In contrast, lentiviral-based knockdown of Abat attenuates the expression of IL-1β-induced catabolic genes in primary murine articular chondrocytes in vitro and also protects against murine articular cartilage degradation in vivo. Strikingly, treatment with the FDA-approved small-molecule Abat inhibitor, vigabatrin, significantly prevents the development of injury-induced OA in mice. In summary, these studies establish Abat as an important new target for therapies to prevent OA.
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MESH Headings
- 4-Aminobutyrate Transaminase/antagonists & inhibitors
- 4-Aminobutyrate Transaminase/genetics
- 4-Aminobutyrate Transaminase/metabolism
- Animals
- Cartilage, Articular/cytology
- Cartilage, Articular/drug effects
- Cartilage, Articular/injuries
- Cartilage, Articular/pathology
- Cells, Cultured
- Chondrocytes/cytology
- Chondrocytes/drug effects
- Chondrocytes/immunology
- Chondrocytes/pathology
- CpG Islands/genetics
- DNA (Cytosine-5-)-Methyltransferases/metabolism
- DNA Methylation/genetics
- Disease Models, Animal
- Gene Knockdown Techniques
- Humans
- Interleukin-1beta/immunology
- Interleukin-1beta/metabolism
- Male
- Mice
- Mitochondria/metabolism
- Osteoarthritis, Knee/drug therapy
- Osteoarthritis, Knee/etiology
- Osteoarthritis, Knee/pathology
- Oxidative Phosphorylation/drug effects
- Primary Cell Culture
- Promoter Regions, Genetic/genetics
- Transcription Initiation Site
- Transcription, Genetic
- Vigabatrin/pharmacology
- Vigabatrin/therapeutic use
- DNA Methyltransferase 3B
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Affiliation(s)
- Jie Shen
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Cuicui Wang
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jun Ying
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang Chinese Medical University, Hangzhou, China
| | - Taotao Xu
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Institute of Orthopaedics and Traumatology, the First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
- Zhejiang Chinese Medical University, Hangzhou, China
| | - Audrey McAlinden
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Cell Biology and Physiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Regis J. O’Keefe
- Department of Orthopaedic Surgery, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
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Jiang X, Lupien-Meilleur A, Tazerart S, Lachance M, Samarova E, Araya R, Lacaille JC, Rossignol E. Remodeled cortical inhibition prevents motor seizures in generalized epilepsy. Ann Neurol 2019; 84:436-451. [PMID: 30048010 DOI: 10.1002/ana.25301] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/12/2018] [Accepted: 07/21/2018] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Deletions of CACNA1A, encoding the α1 subunit of CaV 2.1 channels, cause epilepsy with ataxia in humans. Whereas the deletion of Cacna1a in γ-aminobutyric acidergic (GABAergic) interneurons (INs) derived from the medial ganglionic eminence (MGE) impairs cortical inhibition and causes generalized seizures in Nkx2.1Cre ;Cacna1ac/c mice, the targeted deletion of Cacna1a in somatostatin-expressing INs (SOM-INs), a subset of MGE-derived INs, does not result in seizures, indicating a crucial role of parvalbumin-expressing (PV) INs. Here we identify the cellular and network consequences of Cacna1a deletion specifically in PV-INs. METHODS We generated PVCre ;Cacna1ac/c mutant mice carrying a conditional Cacna1a deletion in PV neurons and evaluated the cortical cellular and network outcomes of this mutation by combining immunohistochemical assays, in vitro electrophysiology, 2-photon imaging, and in vivo video-electroencephalographic recordings. RESULTS PVCre ;Cacna1ac/c mice display reduced cortical perisomatic inhibition and frequent absences but only rare motor seizures. Compared to Nkx2.1Cre ;Cacna1ac/c mice, PVCre ;Cacna1ac/c mice have a net increase in cortical inhibition, with a gain of dendritic inhibition through sprouting of SOM-IN axons, largely preventing motor seizures. This beneficial compensatory remodeling of cortical GABAergic innervation is mTORC1-dependent and its inhibition with rapamycin leads to a striking increase in motor seizures. Furthermore, we show that a direct chemogenic activation of cortical SOM-INs prevents motor seizures in a model of kainate-induced seizures. INTERPRETATION Our findings provide novel evidence suggesting that the remodeling of cortical inhibition, with an mTOR-dependent gain of dendritic inhibition, determines the seizure phenotype in generalized epilepsy and that mTOR inhibition can be detrimental in epilepsies not primarily due to mTOR hyperactivation. Ann Neurol 2018;84:436-451.
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Affiliation(s)
- Xiao Jiang
- Sainte-Justine University Hospital Research Center.,Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
| | | | - Sabrina Tazerart
- Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
| | | | - Elena Samarova
- Sainte-Justine University Hospital Research Center.,Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
| | - Roberto Araya
- Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
| | - Jean-Claude Lacaille
- Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
| | - Elsa Rossignol
- Sainte-Justine University Hospital Research Center.,Department of Neurosciences and the Central Nervous System Research Group, University of Montreal, Montreal, Quebec, Canada
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Lechuga L, Franz DN. Everolimus as adjunctive therapy for tuberous sclerosis complex-associated partial-onset seizures. Expert Rev Neurother 2019; 19:913-925. [PMID: 31335226 DOI: 10.1080/14737175.2019.1635457] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Introduction: Tuberous sclerosis complex (TSC) is a rare genetic disorder resulting in benign tumors in various organs. It is caused by mutations in TSC1 or TSC2 genes causing hyperactivation of the mammalian target of rapamycin (mTOR) pathway. The majority of patients with TSC develop epilepsy, and approximately two-thirds become refractory to antiepileptic drugs (AEDs). Recently, the mTOR inhibitor everolimus was approved as adjunctive therapy for TSC-associated partial seizures. Areas covered: This article covers different characteristics of everolimus, including major clinical trials leading to its approval in TSC-associated partial seizures, safety concerns, drug pharmacokinetics/pharmacodynamics, and an overview of potential competitors and other agents used to treat TSC-associated seizures. Expert opinion: Unlike many other therapies for treating TSC-associated seizures, everolimus addresses the underlying pathophysiology of TSC, and since it has also been shown to improve other TSC manifestations such as subependymal giant cell astrocytomas and renal angiomyolipomas, everolimus provides a potential multisystemic therapy for TSC. An important avenue for future research is exploring the possible use of everolimus as a preventative treatment for seizures as there is the potential to prevent negative developmental outcomes associated with TSC.
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Affiliation(s)
- Lorena Lechuga
- Department of Neurology, Cincinnati Children's Hospital Medical Center , Cincinnati , OH , USA
| | - David Neal Franz
- Pediatrics and Neurology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of medicine , Cincinnati , OH , USA
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30
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Koene LMC, van Grondelle SE, Proietti Onori M, Wallaard I, Kooijman NHRM, van Oort A, Schreiber J, Elgersma Y. Effects of antiepileptic drugs in a new TSC/mTOR-dependent epilepsy mouse model. Ann Clin Transl Neurol 2019; 6:1273-1291. [PMID: 31353861 PMCID: PMC6649373 DOI: 10.1002/acn3.50829] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE An epilepsy mouse model for Tuberous Sclerosis Complex (TSC) was developed and validated to investigate the mechanisms underlying epileptogenesis. Furthermore, the possible antiepileptogenic properties of commonly used antiepileptic drugs (AEDs) and new compounds were assessed. METHODS Tsc1 deletion was induced in CAMK2A-expressing neurons of adult mice. The antiepileptogenic properties of commonly used AEDs and inhibitors of the mTOR pathways were assessed by EEG recordings and by molecular read outs. RESULTS Mice developed epilepsy in a narrow time window (10 ± 2 days) upon Tsc1 gene deletion. Seizure frequency but not duration increased over time. Seizures were lethal within 18 days, were unpredictable, and did not correlate to seizure onset, length or frequency, reminiscent of sudden unexpected death in epilepsy (SUDEP). Tsc1 gene deletion resulted in a strong activation of the mTORC1 pathway, and both epileptogenesis and lethality could be entirely prevented by RHEB1 gene deletion or rapamycin treatment. However, other inhibitors of the mTOR pathway such as AZD8055 and PF4708671 were ineffective. Except for ketogenic diet, none of commonly used AEDs showed an effect on mTORC1 activity. Vigabatrin and ketogenic diet treatment were able to significantly delay seizure onset. In contrast, survival was shortened by lamotrigine. INTERPRETATION This novel Tsc1 mouse model is highly suitable to assess the efficacy of antiepileptic and -epileptogenic drugs to treat mTORC1-dependent epilepsy. Additionally, it allows us to study the mechanisms underlying mTORC1-mediated epileptogenesis and SUDEP. We found that early treatment with vigabatrin was not able to prevent epilepsy, but significantly delayed seizure onset.
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Affiliation(s)
- Linda M. C. Koene
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Saskia E. van Grondelle
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Martina Proietti Onori
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Ilse Wallaard
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Nathalie H. R. M. Kooijman
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Annabel van Oort
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Jadwiga Schreiber
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
| | - Ype Elgersma
- Department of Neuroscience and ENCORE Expertise Center for Neurodevelopmental DisordersErasmus MC University Medical CenterRotterdam3015 CNThe Netherlands
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31
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Yoon DH, Moon JU, Lee JY, Lee IG. Reconsideration of Vigabatrin Effect in Infantile Spasms Treatment. ANNALS OF CHILD NEUROLOGY 2019. [DOI: 10.26815/acn.2019.00094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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32
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Salussolia CL, Klonowska K, Kwiatkowski DJ, Sahin M. Genetic Etiologies, Diagnosis, and Treatment of Tuberous Sclerosis Complex. Annu Rev Genomics Hum Genet 2019; 20:217-240. [PMID: 31018109 DOI: 10.1146/annurev-genom-083118-015354] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that affects multiple organ systems due to an inactivating variant in either TSC1 or TSC2, resulting in the hyperactivation of the mechanistic target of rapamycin (mTOR) pathway. Dysregulated mTOR signaling results in increased cell growth and proliferation. Clinically, TSC patients exhibit great phenotypic variability, but the neurologic and neuropsychiatric manifestations of the disease have the greatest morbidity and mortality. TSC-associated epilepsy occurs in nearly all patients and is often difficult to treat because it is refractory to multiple antiseizure medications. The advent of mTOR inhibitors offers great promise in the treatment of TSC-associated epilepsy and other neurodevelopmental manifestations of the disease; however, the optimal timing of therapeutic intervention is not yet fully understood.
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Affiliation(s)
- Catherine L Salussolia
- F.M. Kirby Neurobiology Center, Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA;
| | - Katarzyna Klonowska
- Division of Pulmonary and Critical Care Medicine and Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - David J Kwiatkowski
- Division of Pulmonary and Critical Care Medicine and Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Mustafa Sahin
- F.M. Kirby Neurobiology Center, Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA;
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Verrotti A, Iapadre G, Di Donato G, Di Francesco L, Zagaroli L, Matricardi S, Belcastro V, Iezzi ML. Pharmacokinetic considerations for anti-epileptic drugs in children. Expert Opin Drug Metab Toxicol 2019; 15:199-211. [PMID: 30689454 DOI: 10.1080/17425255.2019.1575361] [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] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Epilepsy is a chronic and debilitating neurological disease, with a peak of incidence in the first years of life. Today, the vast armamentarium of antiepileptic drugs (AEDs) available make even more challenging to select the most appropriate AED and establish the most effective dosing regimen. In fact, AEDs pharmacokinetics is under the influence of important age-related factors which cannot be ignored. Areas covered: Physiological changes occurring during development age (different body composition, immature metabolic patterns, reduced renal activity) can significantly modify the pharmacokinetic profile of AEDs (adsorption, volume of distribution, half-life, clearance), leading to an altered treatment response. We reviewed the main pharmacokinetic characteristics of AEDs used in children, focusing on age-related factors which are of relevance when treating this patient population. Expert opinion: To deal with this pharmacokinetic variability, physicians have at their disposal two tools: 1) therapeutic drug concentration monitoring, which may help to set the optimal therapeutic regimen for each patient and to monitor eventual fluctuation, and 2) the use of extended-release drug formulations, when available. In the next future, the development of 'ad-hoc' electronic dashboard systems will represent relevant decision-support tools making the AED therapy even more individualized and precise, especially in children.
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Affiliation(s)
- Alberto Verrotti
- a Department of Pediatrics , University of L'Aquila , L'Aquila , Italy
| | - Giulia Iapadre
- a Department of Pediatrics , University of L'Aquila , L'Aquila , Italy
| | - Giulia Di Donato
- a Department of Pediatrics , University of L'Aquila , L'Aquila , Italy
| | | | - Luca Zagaroli
- a Department of Pediatrics , University of L'Aquila , L'Aquila , Italy
| | - Sara Matricardi
- b Child Neurology and Psychiatry Unit , Children's Hospital G. Salesi , Ancona , Italy
| | | | - Maria Laura Iezzi
- a Department of Pediatrics , University of L'Aquila , L'Aquila , Italy
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Fangjing decoction relieves febrile seizures-induced hippocampal neuron apoptosis in rats via regulating the Akt/mTOR pathway. Biosci Rep 2018; 38:BSR20181206. [PMID: 30287501 PMCID: PMC6209604 DOI: 10.1042/bsr20181206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 08/30/2018] [Accepted: 09/13/2018] [Indexed: 12/28/2022] Open
Abstract
Background: Fangjing decoction is a Traditional Chinese Medicine that exhibits anticonvulsive effects in treating febrile seizures (FS). Its action mechanism and the regulation on Akt/mammalian target of rapamycin (mTOR) pathway were revealed in the present study. Methods: FS model was established in Sprague–Dawley rats with or without Fangjing decoction treatment. On day 5, following initiation of drug treatment, seizures were monitored. Hippocampal neuron apoptosis was assessed using terminal dUTP nick end-labeling method. The levels of Bax, protein kinase B (Akt), phospho-Akt (p-Akt), mTOR, and p-mTOR proteins were analyzed using Western blotting. The content of hippocampal γ-aminobutyric acid (GABA) was measured by using ELISA assay. Results: Compared with the control group (n=8), Fangjing decoction effectively shortened escape latency and duration of FS and decreased the frequency of FS in rats (n=8). Concomitantly, the apoptosis of hippocampal neurons, as well as Bax protein levels were also decreased in FS rats which were treated with Fangjing decoction. In addition, the Akt/mTOR signaling was found to be activated in rat hippocampus following FS, as evidenced by increased p-Akt and p-mTOR, while Fangjing decoction could inhibit the activation of Akt/mTOR signaling. Furthermore, the low GABA content in rat hippocampus following FS was significantly elevated by Fangjing decoction treatment. More importantly, SC79, a specific activator for Akt, apparently attenuated the protective effects of Fangjing decoction on FS rats. Conclusion: These results suggest that Fangjing decoction protects the hippocampal neurons from apoptosis by inactivating Akt/mTOR pathway, which may contribute to mitigating FS-induced brain injury.
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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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Common basis for orofacial clefting and cortical interneuronopathy. Transl Psychiatry 2018; 8:8. [PMID: 29317601 PMCID: PMC5802454 DOI: 10.1038/s41398-017-0057-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/11/2017] [Accepted: 10/15/2017] [Indexed: 12/31/2022] Open
Abstract
Orofacial clefts (OFCs) of the lip and/or palate are among the most common human birth defects. Current treatment strategies focus on functional and cosmetic repair but even when this care is available, individuals born with OFCs are at high risk for persistent neurobehavioral problems. In addition to learning disabilities and reduced academic achievement, recent evidence associates OFCs with elevated risk for a constellation of psychiatric outcomes including anxiety disorders, autism spectrum disorder, and schizophrenia. The relationship between these outcomes and OFCs is poorly understood and controversial. Recent neuroimaging studies in humans and mice demonstrate subtle morphological brain abnormalities that co-occur with OFCs but specific molecular and cellular mechanisms have not been investigated. Here, we provide the first evidence directly linking OFC pathogenesis to abnormal development of GABAergic cortical interneurons (cINs). Lineage tracing revealed that the structures that form the upper lip and palate develop in molecular synchrony and spatiotemporal proximity to cINs, suggesting these populations may have shared sensitivity to genetic and/or teratogenic insult. Examination of cIN development in a mouse model of nonsyndromic OFCs revealed significant disruptions in cIN proliferation and migration, culminating in misspecification of the somatostatin-expressing subgroup. These findings reveal a unified developmental basis for orofacial clefting and disrupted cIN development, and may explain the significant overlap in neurobehavioral and psychiatric outcomes associated with OFCs and cIN dysfunction. This emerging mechanistic understanding for increased prevalence of adverse neurobehavioral outcomes in OFC patients is the entry-point for developing evidence-based therapies to improve patient outcomes.
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Davis PE, Filip-Dhima R, Sideridis G, Peters JM, Au KS, Northrup H, Bebin EM, Wu JY, Krueger D, Sahin M. Presentation and Diagnosis of Tuberous Sclerosis Complex in Infants. Pediatrics 2017; 140:peds.2016-4040. [PMID: 29101226 PMCID: PMC5703775 DOI: 10.1542/peds.2016-4040] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/25/2017] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES Tuberous sclerosis complex (TSC) is a neurocutaneous genetic disorder with a high prevalence of epilepsy and neurodevelopmental disorders. TSC can be challenging to diagnose in infants because they often do not show many clinical signs early in life. In this study, we describe the timing and pattern of presenting and diagnostic features in a prospective longitudinal study of infants with TSC. METHODS Two multicenter, prospective studies enrolled 130 infants with definite TSC by clinical or genetic criteria and followed them longitudinally up to 36 months of age. Periodic study visits included medical and seizure histories, physical and neurologic examinations, and developmental assessments. Ages at which major and minor features of TSC and seizures were first identified were analyzed. RESULTS The most common initial presenting features of TSC were cardiac rhabdomyomas (59%) and hypomelanotic macules or other skin findings (39%), and 85% of infants presented with either or both. Ultimately, the most prevalent diagnostic TSC features were hypomelanotic macules (94%), tubers or other cortical dysplasias (94%), subependymal nodules (90%), and cardiac rhabdomyomas (82%). Thirty-five percent of infants presented prenatally, 41% presented at birth or within the first month of life, and 74% met criteria for TSC diagnosis at or within 30 days of presentation. Seizure onset occurred before or at initial presentation in only 15% of infants, but 73% developed epilepsy within the first year of life. CONCLUSIONS Infants with TSC can often be identified early, before the onset of neurologic sequelae, enabling earlier diagnosis, surveillance, and possibly disease-modifying treatment.
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Affiliation(s)
| | - Rajna Filip-Dhima
- F.M. Kirby Neurobiology Center, Boston Children’s Hospital, Harvard Medical School, Harvard University, Boston, Massachusetts
| | | | - Jurriaan M. Peters
- Division of Epilepsy and Clinical Neurophysiology,,Departments of Neurology and
| | - Kit Sing Au
- Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - E. Martina Bebin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Joyce Y. Wu
- Division of Pediatric Neurology, University of California at Los Angeles Mattel Children’s Hospital, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California; and
| | - Darcy Krueger
- Department of Neurology and Rehabilitation Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Mustafa Sahin
- Departments of Neurology and .,F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Harvard University, Boston, Massachusetts
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mTOR-Dependent Cell Proliferation in the Brain. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7082696. [PMID: 29259984 PMCID: PMC5702949 DOI: 10.1155/2017/7082696] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 10/22/2017] [Indexed: 02/08/2023]
Abstract
The mammalian Target of Rapamycin (mTOR) is a molecular complex equipped with kinase activity which controls cell viability being key in the PI3K/PTEN/Akt pathway. mTOR acts by integrating a number of environmental stimuli to regulate cell growth, proliferation, autophagy, and protein synthesis. These effects are based on the modulation of different metabolic pathways. Upregulation of mTOR associates with various pathological conditions, such as obesity, neurodegeneration, and brain tumors. This is the case of high-grade gliomas with a high propensity to proliferation and tissue invasion. Glioblastoma Multiforme (GBM) is a WHO grade IV malignant, aggressive, and lethal glioma. To date, a few treatments are available although the outcome of GBM patients remains poor. Experimental and pathological findings suggest that mTOR upregulation plays a major role in determining an aggressive phenotype, thus determining relapse and chemoresistance. Among several activities, mTOR-induced autophagy suppression is key in GBM malignancy. In this article, we discuss recent evidence about mTOR signaling and its role in normal brain development and pathological conditions, with a special emphasis on its role in GBM.
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Tuchman R. What is the Relationship Between Autism Spectrum Disorders and Epilepsy? Semin Pediatr Neurol 2017; 24:292-300. [PMID: 29249509 DOI: 10.1016/j.spen.2017.10.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The association of epilepsy and autism spectrum disorders (ASD) is best understood by examining the relationship between social cognition, nonsocial cognition, and epilepsy. The relationship between ASD and epilepsy is bidirectional and is strongly linked to intellectual disability (ID). The risk of developing ASD in children with epilepsy is highest in children with early onset seizures, with a high prevalence in children with infantile spasms. The risk of developing epilepsy in children first diagnosed with ASD is highest in those with ID. The prevalence of seizures in ASD increases with age. When epilepsy and ASD coexist, they share common pathophysiological mechanisms. In epilepsy with and without ID, social-cognitive deficits are an important determinant of neurodevelopmental outcomes. Early recognition of social deficits is an important aspect of the comprehensive management of children with epilepsy. Treating the seizures in individuals with epilepsy and ASD is crucial but interventions that address social-cognitive deficits are necessary to maximize neurodevelopmental outcomes.
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Affiliation(s)
- Roberto Tuchman
- From the Department of Neurology, Nicklaus Children's Hospital Miami Children's Health System, Miami, FL.
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40
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Gipson TT, Johnston MV. New insights into the pathogenesis and prevention of tuberous sclerosis-associated neuropsychiatric disorders (TAND). F1000Res 2017; 6. [PMID: 28663780 PMCID: PMC5473405 DOI: 10.12688/f1000research.11110.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/07/2017] [Indexed: 01/13/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is a multi-system disorder resulting from mutations in either the TSC1 or TSC2 genes leading to hyperactivation of mechanistic target of rapamycin (mTOR) signaling. TSC is commonly associated with autism (61%), intellectual disability (45%), and behavioral, psychiatric, intellectual, academic, neuropsychological, and psychosocial difficulties that are collectively referred to as TSC-associated neuropsychiatric disorders (TAND). More than 90% of children with TSC have epilepsy, including infantile spasms, and early onset of seizures, especially infantile spasms, is associated with greater impairment in intellectual development compared with individuals with TSC without seizures. Development of the mTOR inhibitors everolimus and sirolimus has led to considerable progress in the treatment of renal angiomyolipomata, pulmonary lymphangioleiomyomatosis, and subependymal giant cell astrocytomas in the brain. However, similar therapeutic progress is needed in the treatment of TAND.
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Affiliation(s)
- Tanjala T Gipson
- Boling Center for Developmental Disabilities, LeBonheur Children's Hospital, University of Tennessee Health Sciences Center, Memphis, TN, USA
| | - Michael V Johnston
- Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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41
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Stafstrom CE, Staedtke V, Comi AM. Epilepsy Mechanisms in Neurocutaneous Disorders: Tuberous Sclerosis Complex, Neurofibromatosis Type 1, and Sturge-Weber Syndrome. Front Neurol 2017; 8:87. [PMID: 28367137 PMCID: PMC5355446 DOI: 10.3389/fneur.2017.00087] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/24/2017] [Indexed: 01/27/2023] Open
Abstract
Neurocutaneous disorders are multisystem diseases affecting skin, brain, and other organs. Epilepsy is very common in the neurocutaneous disorders, affecting up to 90% of patients with tuberous sclerosis complex (TSC) and Sturge–Weber syndrome (SWS), for example. The mechanisms underlying the increased predisposition to brain hyperexcitability differ between disorders, yet some molecular pathways overlap. For instance, the mechanistic target of rapamycin (mTOR) signaling cascade plays a central role in seizures and epileptogenesis in numerous acquired and genetic disorders, including several neurocutaneous disorders. Potential routes for target-specific treatments are emerging as the genetic and molecular pathways involved in neurocutaneous disorders become increasingly understood. This review explores the clinical features and mechanisms of epilepsy in three common neurocutaneous disorders—TSC, neurofibromatosis type 1, and SWS.
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Affiliation(s)
- Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Verena Staedtke
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine , Baltimore, MD , USA
| | - Anne M Comi
- Department of Neurology, Kennedy Krieger Institute, Johns Hopkins University School of Medicine , Baltimore, MD , USA
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42
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Abstract
OBJECTIVE Epilepsy is a chronic neurological disease characterised with seizures. The aetiology of the most generalised epilepsies cannot be explicitly determined and the seizures are pronounced to be genetically determined by disturbances of receptors in central nervous system. Besides, neurotransmitter distributions or other metabolic problems are supposed to involve in epileptogenesis. Lack of adequate data about pharmacological agents that have antiepileptogenic effects point to need of research on this field. Thus, in this review, inflammatory aspects of epileptogenesis has been focussed via considering several concepts like role of immune system, blood-brain barrier and antibody involvement in epileptogenesis. METHODS We conducted an evidence-based review of the literatures in order to evaluate the possible participation of inflammatory processes to epileptogenesis and also, promising agents which are effective to these processes. We searched PubMed database up to November 2015 with no date restrictions. RESULTS In the present review, 163 appropriate articles were included. Obtained data suggests that inflammatory processes participate to epileptogenesis in several ways like affecting fibroblast growth factor-2 and tropomyosin receptor kinase B signalling pathways, detrimental proinflammatory pathways [such as the interleukin-1 beta (IL-1β)-interleukin-1 receptor type 1 (IL-1R1) system], mammalian target of rapamycin pathway, microglial activities, release of glial inflammatory proteins (such as macrophage inflammatory protein, interleukin 6, C-C motif ligand 2 and IL-1β), adhesion molecules that are suggested to function in signalling pathways between neurons and microglia and also linkage between these molecules and proinflammatory cytokines. CONCLUSION The literature research indicated that inflammation is a part of epileptogenesis. For this reason, further studies are necessary for assessing agents that will be effective in clinical use for therapeutic treatment of epileptogenesis.
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43
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Vogel KR, Ainslie GR, Schmidt MA, Wisor JP, Gibson KM. mTOR Inhibition Mitigates Molecular and Biochemical Alterations of Vigabatrin-Induced Visual Field Toxicity in Mice. Pediatr Neurol 2017; 66:44-52.e1. [PMID: 27816307 PMCID: PMC5866057 DOI: 10.1016/j.pediatrneurol.2016.09.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/21/2016] [Accepted: 09/25/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND Gamma-vinyl-γ-aminobutyric acid (GABA) (vigabatrin) is an antiepileptic drug and irreversible GABA transaminase inhibitor associated with visual field impairment, which limits its clinical utility. We sought to relate altered visual evoked potentials associated with vigabatrin intake to transcriptional changes in the mechanistic target of rapamycin (mTOR) pathway and GABA receptors to expose further mechanisms of vigabatrin-induced visual field loss. METHODS Vigabatrin was administered to mice via an osmotic pump for two weeks to increase GABA levels. Visual evoked potentials were examined, eye samples were collected, and gene expression was measured by quantitative reverse transcription-polymerase chain reaction. Similarly, human retinal pigment epithelial cells (ARPE19) were exposed to vigabatrin and treated with mTOR inhibitors for mTOR pathway analysis and to assess alterations in organelle accumulation by microscopy. RESULTS Dysregulated expression of transcripts in the mTOR pathway, GABAA/B receptors, metabotropic glutamate (Glu) receptors 1/6, and GABA/glutamate transporters in the eye were found in association with visual evoked potential changes during vigabatrin administration. Rrag genes were upregulated in both mouse eye and ARPE19 cells. Immunoblot of whole eye revealed greater than three fold upregulation of a 200 kDa band when immunoblotted for ras-related guanosine triphosphate binding D. Microscopy of ARPE19 cells revealed selective reversal of vigabatrin-induced organelle accumulation by autophagy-inducing drugs, notably Torin 2. Changes in the mTOR pathway gene expression, including Rrag genes, were corrected by Torin 2 in ARPE19 cells. CONCLUSIONS Our studies, indicating GABA-associated augmentation of RRAG and mTOR signaling, support further preclinical evaluation of mTOR inhibitors as a therapeutic strategy to potentially mitigate vigabatrin-induced ocular toxicity.
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Affiliation(s)
- Kara R Vogel
- Division of Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington
| | - Garrett R Ainslie
- Division of Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington
| | - Michelle A Schmidt
- Elson S. Floyd College of Medicine, Washington State University, Spokane, Washington
| | - Jonathan P Wisor
- Elson S. Floyd College of Medicine, Washington State University, Spokane, Washington
| | - K Michael Gibson
- Division of Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington.
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Curatolo P, Bjørnvold M, Dill PE, Ferreira JC, Feucht M, Hertzberg C, Jansen A, Jóźwiak S, Kingswood JC, Kotulska K, Macaya A, Moavero R, Nabbout R, Zonnenberg BA. The Role of mTOR Inhibitors in the Treatment of Patients with Tuberous Sclerosis Complex: Evidence-based and Expert Opinions. Drugs 2016; 76:551-65. [PMID: 26927950 DOI: 10.1007/s40265-016-0552-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Tuberous sclerosis complex (TSC) is a genetic disorder arising from mutations in the TSC1 or TSC2 genes. The resulting over-activation of the mammalian target of rapamycin (mTOR) signalling pathway leaves patients with TSC susceptible to the growth of non-malignant tumours in multiple organs. Previously, surgery was the main therapeutic option for TSC. However, pharmacological therapy with mTOR inhibitors such as everolimus and sirolimus is now emerging as an alternate approach. Everolimus and sirolimus have already been shown to be effective in treating subependymal giant cell astrocytoma (SEGA) and renal angiomyolipoma (AML), and everolimus is currently being evaluated in treating TSC-related epilepsy. In November 2013 a group of European experts convened to discuss the current options and practical considerations for treating various manifestations of TSC. This article provides evidence-based recommendations for the treatment of SEGA, TSC-related epilepsy and renal AML, with a focus on where mTOR inhibitor therapy may be considered alongside other treatment options. Safety considerations regarding mTOR inhibitor therapy are also reviewed. With evidence of beneficial effects in neurological and non-neurological TSC manifestations, mTOR inhibitors may represent a systemic treatment for TSC.
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Affiliation(s)
- Paolo Curatolo
- Department of Neurosciences, Child Neurology and Psychiatry Unit, Tor Vergata University Hospital of Rome, Rome, Italy.
| | - Marit Bjørnvold
- National Center for Rare Epilepsy-related Disorders, National Center of Epilepsy, Oslo University Hospital, Oslo, Norway
| | - Patricia E Dill
- Department of Pediatric Neurology and Developmental Medicine, University Children's Hospital Basel, University of Basel, Basel, Switzerland.,INSERM Unité 1511, Paris, France
| | - José Carlos Ferreira
- Neuro Pediatra, Centro Hospitalar Lisboa Ocidental, Hospital São Francisco Xavier, Lisbon, Portugal
| | - Martha Feucht
- Department of Paediatrics, University Hospital Vienna, Vienna, Austria
| | - Christoph Hertzberg
- Diagnose und Behandlungszentrum für Kinder und Jugendliche, Vivantes Klinikum Neukölln, Berlin, Germany
| | - Anna Jansen
- Pediatric Neurology Unit-UZ Brussel, Brussels, Belgium
| | - Sergiusz Jóźwiak
- Department of Child Neurology, Medical University of Warsaw, Warsaw, Poland
| | - J Christopher Kingswood
- Sussex Renal Unit, Royal Sussex County Hospital, Brighton, UK.,The Trafford Department of Renal Medicine, Royal Sussex County Hospital, Brighton, UK
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | - Alfons Macaya
- Servei de Neurologia Pediàtrica, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - Romina Moavero
- Department of Neurosciences, Child Neurology and Psychiatry Unit, Tor Vergata University Hospital of Rome, Rome, Italy.,Pediatric Neurology Unit, Department of Neuroscience and Neurorehabilitation, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Rima Nabbout
- Department of Pediatric Neurology, Reference Centre for Rare Epilepsies and Tuberous Sclerosis Complex, Necker-Enfants Malades Hospital, University Paris Descartes, Paris, France
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Russo E, Citraro R, Constanti A, Leo A, Lüttjohann A, van Luijtelaar G, De Sarro G. Upholding WAG/Rij rats as a model of absence epileptogenesis: Hidden mechanisms and a new theory on seizure development. Neurosci Biobehav Rev 2016; 71:388-408. [DOI: 10.1016/j.neubiorev.2016.09.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 09/19/2016] [Indexed: 02/06/2023]
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Switon K, Kotulska K, Janusz-Kaminska A, Zmorzynska J, Jaworski J. Tuberous sclerosis complex: From molecular biology to novel therapeutic approaches. IUBMB Life 2016; 68:955-962. [PMID: 27797139 DOI: 10.1002/iub.1579] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 10/09/2016] [Indexed: 12/20/2022]
Abstract
Tuberous sclerosis complex (TSC) is a rare multi-system disorder, primary manifestations of which are benign tumors and lesions in various organs of the body, including the brain. TSC patients often suffer from epilepsy, mental retardation, and autism spectrum disorder (ASD). Therefore, TSC serves as a model of epilepsy, ASD, and tumorigenesis. TSC is caused by the lack of functional Tsc1-Tsc2 complex, which serves as a major cellular inhibitor of mammalian Target of Rapamycin Complex 1 (mTORC1). mTORC1 is a kinase controlling most of anabolic processes in eukaryotic cells. Consequently, mTORC1 inhibitors, such as rapamycin, serve as experimental or already approved drugs for several TSC symptoms. However, rapalogs, although quite effective, need to be administered chronically and likely for a lifetime, since therapy discontinuation results in tumor regrowth and epilepsy recurrence. Recent studies revealed that metabolism and excitability (in the case of neurons) of cells lacking Tsc1-Tsc2 complex are changed, and these features may potentially be used to treat some of TSC symptoms. In this review, we first provide basic facts about TSC and its molecular background, to next discuss the newest findings in TSC cell biology that can be used to improve existing therapies of TSC and other diseases linked to mTORC1 hyperactivation. © 2016 IUBMB Life, 68(12):955-962, 2016.
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Affiliation(s)
- Katarzyna Switon
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, Children's Memorial Health Institute, Warsaw, Poland
| | - Aleksandra Janusz-Kaminska
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Justyna Zmorzynska
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jacek Jaworski
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
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47
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Hatori T, Sugiyama Y, Yamashita S, Hirakubo Y, Nonaka K, Ichihashi K. Vigabatrin Therapy for Infantile Spasms in a Case of Cardiofaciocutaneous Syndrome with Cardiac Hypertrophy Developing during Adrenocorticotropic Hormone Treatment. J NIPPON MED SCH 2016; 83:167-71. [PMID: 27680485 DOI: 10.1272/jnms.83.167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In a patient with cardiofaciocutaneous syndrome complicated by intractable infantile spasms (West syndrome), cardiac hypertrophy developed during adrenocorticotropic hormone treatment. Various types of antiepileptic drugs, intravenous immunoglobulin, thyrotropin releasing hormone, and a ketogenic diet were ineffective in this case. However, vigabatrin both decreased clinical seizures and improved electroencephalogram findings. Although vigabatrin has not been approved for use in Japan, the results in the present case suggest that this drug should be considered as an alternative therapy for cases of infantile spasms associated with syndromes involving cardiomyopathy or its potential risk factors, such as cardiofaciocutaneous syndrome.
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Affiliation(s)
- Takayuki Hatori
- Department of Pediatrics, Jichi Medical University Saitama Medical Center
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Joshi K, Shen L, Michaeli A, Salter M, Thibault-Messier G, Hashmi S, Eubanks JH, Cortez MA, Snead OC. Infantile spasms in down syndrome: Rescue by knockdown of the GIRK2 channel. Ann Neurol 2016; 80:511-21. [PMID: 27462820 DOI: 10.1002/ana.24749] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/25/2016] [Accepted: 07/25/2016] [Indexed: 02/05/2023]
Abstract
OBJECTIVE The Ts65Dn (Ts) mouse model of Down syndrome (DS) is exquisitely sensitive to an infantile spasms phenotype induced by γ-aminobutyric acidB receptor (GABAB R) agonists. The Ts mouse contains the core genomic triplication of the DS critical region, which includes 3 copies of the Kcnj6 gene that encodes the GABAB R-coupled G protein-coupled inward rectifying potassium channel subunit 2 (GIRK2) channel. We test the hypothesis that GIRK2 is necessary for the GABAB R agonist-induced infantile spasms phenotype in Ts. METHODS We assessed the result of either genetic or pharmacological knockdown of the GIRK2 channel in Ts brain upon the GABAB R agonist-induced infantile spasms phenotype in the Ts mouse model of DS. As well, we examined GABAB R currents in hippocampal neurons prepared from GIRK2-trisomic Ts control mice and GIRK2-disomic Ts mice in which Kcnj6 had been genetically knocked down from 3 to 2 copies. RESULTS The reduction of the copy number of Kcnj6 in Ts mice rescued the GABAB R agonist-induced infantile spasms phenotype. There was an increase in GABAB R-mediated GIRK2 currents in GIRK2-trisomic Ts mouse hippocampal neurons, which were normalized in the GIRK2-disomic Ts mice. Similarly, pharmacological knockdown of the GIRK2 channel in Ts brain using the GIRK antagonist tertiapin-Q also rescued the GABAB R agonist-induced infantile spasms phenotype in Ts mutants. INTERPRETATION The GABAB R-coupled GIRK2 channel is necessary for the GABAB R agonist-induced infantile spasms phenotype in the Ts mouse and may represent a novel therapeutic target for the treatment of infantile spasms in DS. Ann Neurol 2016;80:511-521.
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Affiliation(s)
- Krutika Joshi
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada. .,Department of Pharmacology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
| | - Lily Shen
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Avner Michaeli
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Michael Salter
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute of Medical Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Sumaiya Hashmi
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada
| | - James H Eubanks
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Department of Surgery, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,University Health Network, Toronto Western Research Institute, Toronto, Ontario, Canada
| | - Miguel A Cortez
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Pediatrics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - O Carter Snead
- Neuroscience and Mental Health Program, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Pharmacology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute of Medical Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Department of Pediatrics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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Citraro R, Leo A, Constanti A, Russo E, De Sarro G. mTOR pathway inhibition as a new therapeutic strategy in epilepsy and epileptogenesis. Pharmacol Res 2016; 107:333-343. [DOI: 10.1016/j.phrs.2016.03.039] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/23/2016] [Accepted: 03/31/2016] [Indexed: 12/24/2022]
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Early onset epileptic encephalopathy or genetically determined encephalopathy with early onset epilepsy? Lessons learned from TSC. Eur J Paediatr Neurol 2016; 20:203-211. [PMID: 26758984 DOI: 10.1016/j.ejpn.2015.12.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 12/01/2015] [Accepted: 12/13/2015] [Indexed: 01/12/2023]
Abstract
BACKGROUND In tuberous sclerosis complex (TSC) a relationship has been shown between early and refractory seizures and intellectual disability. However, it is uncertain whether epilepsy in TSC is simply a marker in infants who are destined to develop an encephalopathic process or if seizures play a causal role in developing an encephalopathy. METHODS This paper summarizes the key points discussed during a European TSC workshop held in Rome, and reviews the experimental and clinical evidence in support of the two theories. RESULTS/CONCLUSION There are many factors that influence the appearance of both early seizure onset and the encephalopathy resulting in neurodevelopmental deficits. Experimental studies show that as a consequence of the TSC genes mutation, mammalian target of Rapamycin (mTOR) overactivation determines an alteration in cellular morphology with cytomegalic neurons, altered synaptogenesis and an imbalance between excitation/inhibition, thus providing a likely neuroanatomical substrate for the early appearance of refractory seizures and for the encephalopathic process. At the clinical level, early signs of altered developmental trajectories are often unrecognized before 12 months of age. Evidence from experimental research shows that encephalopathy in TSC might have a genetic cause, and mTOR activation caused by TSC gene mutation can be directly responsible for the early appearance of seizures and encephalopathy.
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