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Patil RP, Kumar N, Kaur A, Munian RK, Bhattacharya B, Ganesh S, Parihar R. Retinal vascular pathology in a mouse model of Lafora progressive myoclonus epilepsy. Neurosci Res 2024; 204:58-63. [PMID: 38458494 DOI: 10.1016/j.neures.2024.02.004] [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: 08/10/2023] [Revised: 02/20/2024] [Accepted: 02/29/2024] [Indexed: 03/10/2024]
Abstract
Neurodegenerative diseases (ND) affect distinct populations of neurons and manifest various clinical and pathological symptoms. A subset of ND prognoses has been linked to vascular risk factors. Consequently, the current study investigated retinal vascular abnormalities in a murine model of Lafora neurodegenerative disease (LD), a fatal and genetic form of progressive myoclonus epilepsy that affects children. Here, arterial rigidity was evaluated by measuring pulse wave velocity and vasculature deformations in the retina. Our findings in the LD mouse model indicate altered pulse wave velocity, retinal vascular thinning, and convoluted retinal arteries.
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Affiliation(s)
- Ruchira Pranay Patil
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Nitin Kumar
- Central Experimental Animal Facility, Indian Institute of Technology, Kanpur, India
| | - Arveen Kaur
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Rajendra Kumar Munian
- Department of Mechanical Engineering, Indian Institute of Technology, Kanpur, India; Department of Mechanical Engineering, Indian Institute of Technology Ropar, India
| | - Bishakh Bhattacharya
- Department of Mechanical Engineering, Indian Institute of Technology, Kanpur, India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India; Central Experimental Animal Facility, Indian Institute of Technology, Kanpur, India; The Mehta Family Centre for Engineering in Medicine, Indian Institute of Technology Kanpur, India.
| | - Rashmi Parihar
- Central Experimental Animal Facility, Indian Institute of Technology, Kanpur, India.
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Ferrari Aggradi CR, Rimoldi M, Romagnoli G, Velardo D, Meneri M, Iacobucci D, Ripolone M, Napoli L, Ciscato P, Moggio M, Comi GP, Ronchi D, Corti S, Abati E. Lafora Disease: A Case Report and Evolving Treatment Advancements. Brain Sci 2023; 13:1679. [PMID: 38137127 PMCID: PMC10742041 DOI: 10.3390/brainsci13121679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/20/2023] [Accepted: 12/03/2023] [Indexed: 12/24/2023] Open
Abstract
Lafora disease is a rare genetic disorder characterized by a disruption in glycogen metabolism. It manifests as progressive myoclonus epilepsy and cognitive decline during adolescence. Pathognomonic is the presence of abnormal glycogen aggregates that, over time, produce large inclusions (Lafora bodies) in various tissues. This study aims to describe the clinical and histopathological aspects of a novel Lafora disease patient, and to provide an update on the therapeutical advancements for this disorder. A 20-year-old Libyan boy presented with generalized tonic-clonic seizures, sporadic muscular jerks, eyelid spasms, and mental impairment. Electroencephalography showed multiple discharges across both brain hemispheres. Brain magnetic resonance imaging was unremarkable. Muscle biopsy showed increased lipid content and a very mild increase of intermyofibrillar glycogen, without the polyglucosan accumulation typically observed in Lafora bodies. Despite undergoing three lines of antiepileptic treatment, the patient's condition showed minimal to no improvement. We identified the homozygous variant c.137G>A, p.(Cys46Tyr), in the EPM2B/NHLRC1 gene, confirming the diagnosis of Lafora disease. To our knowledge, the presence of lipid aggregates without Lafora bodies is atypical. Lafora disease should be considered during the differential diagnosis of progressive, myoclonic, and refractory epilepsies in both children and young adults, especially when accompanied by cognitive decline. Although there are no effective therapies yet, the development of promising new strategies prompts the need for an early and accurate diagnosis.
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Affiliation(s)
- Carola Rita Ferrari Aggradi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
| | - Martina Rimoldi
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
- Medical Genetics Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Gloria Romagnoli
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
| | - Daniele Velardo
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Megi Meneri
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
- Stroke Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Davide Iacobucci
- Neurology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Michela Ripolone
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Laura Napoli
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Patrizia Ciscato
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Maurizio Moggio
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Giacomo Pietro Comi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
- Neurology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Dario Ronchi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
- Neurology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy; (M.R.); (D.V.); (M.R.); (P.C.); (M.M.)
| | - Elena Abati
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy; (C.R.F.A.); (G.R.); (M.M.); (G.P.C.); (D.R.)
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Abraham JR, Allen FM, Barnard J, Schlatzer D, Natowicz MR. Proteomic investigations of adult polyglucosan body disease: insights into the pathobiology of a neurodegenerative disorder. Front Neurol 2023; 14:1261125. [PMID: 38033781 PMCID: PMC10683643 DOI: 10.3389/fneur.2023.1261125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 09/26/2023] [Indexed: 12/02/2023] Open
Abstract
Inadequate glycogen branching enzyme 1 (GBE1) activity results in different forms of glycogen storage disease type IV, including adult polyglucosan body disorder (APBD). APBD is clinically characterized by adult-onset development of progressive spasticity, neuropathy, and neurogenic bladder and is histologically characterized by the accumulation of structurally abnormal glycogen (polyglucosan bodies) in multiple cell types. How insufficient GBE1 activity causes the disease phenotype of APBD is poorly understood. We hypothesized that proteomic analysis of tissue from GBE1-deficient individuals would provide insights into GBE1-mediated pathobiology. In this discovery study, we utilized label-free LC-MS/MS to quantify the proteomes of lymphoblasts from 3 persons with APBD and 15 age- and gender-matched controls, with validation of the findings by targeted MS. There were 531 differentially expressed proteins out of 3,427 detected between APBD subjects vs. controls, including pronounced deficiency of GBE1. Bioinformatic analyses indicated multiple canonical pathways and protein-protein interaction networks to be statistically markedly enriched in APBD subjects, including: RNA processing/transport/translation, cell cycle control/replication, mTOR signaling, protein ubiquitination, unfolded protein and endoplasmic reticulum stress responses, glycolysis and cell death/apoptosis. Dysregulation of these processes, therefore, are primary or secondary factors in APBD pathobiology in this model system. Our findings further suggest that proteomic analysis of GBE1 mutant lymphoblasts can be leveraged as part of the screening for pharmaceutical agents for the treatment of APBD.
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Affiliation(s)
- Joseph R. Abraham
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States
| | - Frederick M. Allen
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States
| | - John Barnard
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Daniela Schlatzer
- Center for Proteomics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Marvin R. Natowicz
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States
- Pathology and Laboratory Medicine, Genomic Medicine, Neurological and Pediatrics Institutes, Cleveland Clinic, Cleveland, OH, United States
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Pondrelli F, Minardi R, Muccioli L, Zenesini C, Vignatelli L, Licchetta L, Mostacci B, Tinuper P, Vander Kooi CW, Gentry MS, Bisulli F. Prognostic value of pathogenic variants in Lafora Disease: systematic review and meta-analysis of patient-level data. Orphanet J Rare Dis 2023; 18:263. [PMID: 37658439 PMCID: PMC10474773 DOI: 10.1186/s13023-023-02880-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 08/24/2023] [Indexed: 09/03/2023] Open
Abstract
BACKGROUND Lafora disease (LD) is a fatal form of progressive myoclonic epilepsy caused by biallelic pathogenic variants in EPM2A or NHLRC1. With a few exceptions, the influence of genetic factors on disease progression has yet to be confirmed. We present a systematic review and meta-analysis of the known pathogenic variants to identify genotype-phenotype correlations. METHODS We collected all reported cases with genetically-confirmed LD containing data on disease history. Pathogenic variants were classified into missense (MS) and protein-truncating (PT). Three genotype classes were defined according to the combination of the variants: MS/MS, MS/PT, and PT/PT. Time-to-event analysis was performed to evaluate survival and loss of autonomy. RESULTS 250 cases described in 70 articles were included. The mutated gene was NHLRC1 in 56% and EPM2A in 44% of cases. 114 pathogenic variants (67 EPM2A; 47 NHLRC1) were identified. The NHLRC1 genotype PT/PT was associated with shorter survival [HR 2.88; 95% CI 1.23-6.78] and a trend of higher probability of loss of autonomy [HR 2.03, 95% CI 0.75-5.56] at the multivariable Cox regression analysis. The population carrying the homozygous p.Asp146Asn variant of NHLRC1 genotype was confirmed to have a more favourable prognosis in terms of disease duration. CONCLUSIONS This study demonstrates the existence of prognostic genetic factors in LD, namely the genotype defined according to the functional impact of the pathogenic variants. Although the reasons why NHLRC1 genotype PT/PT is associated with a poorer prognosis have yet to be fully elucidated, it may be speculated that malin plays a pivotal role in LD pathogenesis.
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Affiliation(s)
- Federica Pondrelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Raffaella Minardi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
| | - Lorenzo Muccioli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
| | - Corrado Zenesini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
| | - Luca Vignatelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
| | - Laura Licchetta
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
| | - Barbara Mostacci
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
| | - Paolo Tinuper
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Craig W Vander Kooi
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, USA
| | - Matthew S Gentry
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, USA
| | - Francesca Bisulli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the European Reference Network for Rare and Complex Epilepsies (EpiCARE), Bologna, Italy
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Burgos DF, Sciaccaluga M, Worby CA, Zafra-Puerta L, Iglesias-Cabeza N, Sánchez-Martín G, Prontera P, Costa C, Serratosa JM, Sánchez MP. Epm2a R240X knock-in mice present earlier cognitive decline and more epileptic activity than Epm2a -/- mice. Neurobiol Dis 2023; 181:106119. [PMID: 37059210 DOI: 10.1016/j.nbd.2023.106119] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 04/02/2023] [Accepted: 04/05/2023] [Indexed: 04/16/2023] Open
Abstract
Lafora disease is a rare recessive form of progressive myoclonic epilepsy, usually diagnosed during adolescence. Patients present with myoclonus, neurological deterioration, and generalized tonic-clonic, myoclonic, or absence seizures. Symptoms worsen until death, usually within the first ten years of clinical onset. The primary histopathological hallmark is the formation of aberrant polyglucosan aggregates called Lafora bodies in the brain and other tissues. Lafora disease is caused by mutations in either the EPM2A gene, encoding laforin, or the EPM2B gene, coding for malin. The most frequent EPM2A mutation is R241X, which is also the most prevalent in Spain. The Epm2a-/- and Epm2b-/- mouse models of Lafora disease show neuropathological and behavioral abnormalities similar to those seen in patients, although with a milder phenotype. To obtain a more accurate animal model, we generated the Epm2aR240X knock-in mouse line with the R240X mutation in the Epm2a gene, using genetic engineering based on CRISPR-Cas9 technology. Epm2aR240X mice exhibit most of the alterations reported in patients, including the presence of LBs, neurodegeneration, neuroinflammation, interictal spikes, neuronal hyperexcitability, and cognitive decline, despite the absence of motor impairments. The Epm2aR240X knock-in mouse displays some symptoms that are more severe that those observed in the Epm2a-/- knock-out, including earlier and more pronounced memory loss, increased levels of neuroinflammation, more interictal spikes and increased neuronal hyperexcitability, symptoms that more precisely resemble those observed in patients. This new mouse model can therefore be specifically used to evaluate how new therapies affects these features with greater precision.
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Affiliation(s)
- Daniel F Burgos
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain; Program in Neuroscience, Autonoma de Madrid University-Cajal Institute, Madrid 28029, Spain
| | - Miriam Sciaccaluga
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia 06132, Italy; Fondazione Malattie Rare Mauro Baschirotto BIRD Onlus, Longare (VI), Italy
| | - Carolyn A Worby
- University of California at San Diego, 9500 Gilman Drive, La Jolla CA92093-0721, USA
| | - Luis Zafra-Puerta
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain; Program in Neuroscience, Autonoma de Madrid University-Cajal Institute, Madrid 28029, Spain; Fondazione Malattie Rare Mauro Baschirotto BIRD Onlus, Longare (VI), Italy
| | - Nerea Iglesias-Cabeza
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Gema Sánchez-Martín
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Paolo Prontera
- Medical Genetics Unit, S. Maria della Misericordia Hospital, Perugia 06132, Italy
| | - Cinzia Costa
- Section of Neurology, S. Maria della Misericordia Hospital, Department of Medicine and Surgery, University of Perugia, Perugia 06132, Italy
| | - José M Serratosa
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Marina P Sánchez
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain.
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Della Vecchia S, Marchese M, Santorelli FM. Glial Contributions to Lafora Disease: A Systematic Review. Biomedicines 2022; 10:biomedicines10123103. [PMID: 36551859 PMCID: PMC9776290 DOI: 10.3390/biomedicines10123103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Lafora disease (LD) is a neurodegenerative condition characterized by the accumulation of polyglucosan bodies (PBs) throughout the brain. Alongside metabolic and molecular alterations, neuroinflammation has emerged as another key histopathological feature of LD. METHODS To investigate the role of astrocytes and microglia in LD, we performed a systematic review according to the PRISMA statement. PubMed, Scopus, and Web-of-Science database searches were performed independently by two reviewers. RESULTS Thirty-five studies analyzing the relationship of astrocytes and microglia with LD and/or the effects of anti-inflammatory treatments in LD animal models were identified and included in the review. Although LD has long been dominated by a neuronocentric view, a growing body of evidence suggests a role of glial cells in the disease, starting with the finding that these cells accumulate PBs. We discuss the potential meaning of glial PB accumulations, the likely factors activating glial cells, and the possible contribution of glial cells to LD neurodegeneration and epilepsy. CONCLUSIONS Given the evidence for the role of neuroinflammation in LD, future studies should consider glial cells as a potential therapeutic target for modifying/delaying LD progression; however, it should be kept in mind that these cells can potentially assume multiple reactive phenotypes, which could influence the therapeutic response.
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Affiliation(s)
- Stefania Della Vecchia
- Molecular Medicine and Neurogenetics, IRCCS Stella Maris Foundation, Calambrone, 56128 Pisa, Italy
- Correspondence: (S.D.V.); (F.M.S.)
| | - Maria Marchese
- Neurobiology, IRCCS Stella Maris Foundation, Calambrone, 56128 Pisa, Italy
| | - Filippo Maria Santorelli
- Molecular Medicine and Neurogenetics, IRCCS Stella Maris Foundation, Calambrone, 56128 Pisa, Italy
- Neurobiology, IRCCS Stella Maris Foundation, Calambrone, 56128 Pisa, Italy
- Correspondence: (S.D.V.); (F.M.S.)
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Sinha P, Verma B, Ganesh S. Age-Dependent Reduction in the Expression Levels of Genes Involved in Progressive Myoclonus Epilepsy Correlates with Increased Neuroinflammation and Seizure Susceptibility in Mouse Models. Mol Neurobiol 2022; 59:5532-5548. [PMID: 35732865 DOI: 10.1007/s12035-022-02928-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 06/14/2022] [Indexed: 11/28/2022]
Abstract
Brain aging is characterized by a gradual decline in cellular homeostatic processes, thereby losing the ability to respond to physiological stress. At the anatomical level, the aged brain is characterized by degenerating neurons, proteinaceous plaques and tangles, intracellular deposition of glycogen, and elevated neuroinflammation. Intriguingly, such age-associated changes are also seen in neurodegenerative disorders suggesting that an accelerated aging process could be one of the contributory factors for the disease phenotype. Amongst these, the genetic forms of progressive myoclonus epilepsy (PME), resulting from loss-of-function mutations in genes, manifest symptoms that are common to age-associated disorders, and genes mutated in PME are involved in the cellular homeostatic processes. Intriguingly, the incidence and/or onset of epileptic seizures are known to increase with age, suggesting that physiological changes in the aged brain might contribute to increased susceptibility to seizures. We, therefore, hypothesized that the expression level of genes implicated in PME might decrease with age, thereby leading to a compromised neuronal response towards physiological stress and hence neuroinflammation in the aging brain. Using mice models, we demonstrate here that the expression level of PME genes shows an inverse correlation with age, neuroinflammation, and compromised heat shock response. We further show that the pharmacological suppression of neuroinflammation ameliorates seizure susceptibility in aged animals as well as in animal models for a PME. Taken together, our results indicate a functional role for the PME genes in normal brain aging and that neuroinflammation could be a major contributory player in susceptibility to seizures.
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Affiliation(s)
- Priyanka Sinha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur, 208016, India
| | - Bhupender Verma
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur, 208016, India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Uttar Pradesh, Kanpur, 208016, India. .,Mehta Family Center for Engineering in Medicine, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
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Trehalose Treatment in Zebrafish Model of Lafora Disease. Int J Mol Sci 2022; 23:ijms23126874. [PMID: 35743315 PMCID: PMC9224929 DOI: 10.3390/ijms23126874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/15/2022] [Accepted: 06/17/2022] [Indexed: 01/18/2023] Open
Abstract
Mutations in the EPM2A gene encoding laforin cause Lafora disease (LD), a progressive myoclonic epilepsy characterized by drug-resistant seizures and progressive neurological impairment. To date, rodents are the only available models for studying LD; however, their use for drug screening is limited by regulatory restrictions and high breeding costs. To investigate the role of laforin loss of function in early neurodevelopment, and to screen for possible new compounds for treating the disorder, we developed a zebrafish model of LD. Our results showed the epm2a−/− zebrafish to be a faithful model of LD, exhibiting the main disease features, namely motor impairment and neuronal hyperexcitability with spontaneous seizures. The model also showed increased inflammatory response and apoptotic death, as well as an altered autophagy pathway that occurs early in development and likely contributes to the disease progression. Early administration of trehalose was found to be effective for rescuing motor impairment and neuronal hyperexcitability associated with seizures. Our study adds a new tool for investigating LD and might help to identify new treatment opportunities.
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Xingxua T, Xinjuan L, Yuncan C, Dongyan W. Compound heterozygosity for novel variations of the NHLRC1 Gene in a family with Lafora Disease. Clin Neurol Neurosurg 2022; 218:107255. [DOI: 10.1016/j.clineuro.2022.107255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/11/2022] [Accepted: 04/15/2022] [Indexed: 11/28/2022]
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10
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Sheshadri D, Onkar A, Ganesh S. Alterations in brain glycogen levels influence life-history traits and reduce the lifespan in female Drosophila melanogaster. Biol Open 2021; 10:273730. [PMID: 34817590 PMCID: PMC8689487 DOI: 10.1242/bio.059055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/15/2021] [Indexed: 11/20/2022] Open
Abstract
Sexual dimorphism in lifespan, wherein females outlive males, is evident across all animal taxa. The longevity difference between sexes is controlled by multiple physiological processes with complex relationships to one another. In recent years, glycogen, the storage form of glucose, has been shown to cause rapid aging upon forced synthesis in healthy neurons. Glycogen in the form of corpora amylacea in the aging brain is also widely reported. While these studies did suggest a novel role for glycogen in aging, most of them have focused on pooled samples, and have not looked at sex-specific effects, if any. Given the widespread occurrence of sex-biased expression of genes and the underlying physiology, it is important to look at the sex-specific effects of metabolic processes. In the present study, using transgenic fly lines for the human glycogen synthase, we investigated the sex-specific effects of glycogen on stress resistance, fitness, and survival. We demonstrate that Drosophila melanogaster females with altered levels of glycogen in the brain display a shortened lifespan, increased resistance to starvation, and higher oxidative stress than male flies. The present study thus provides a novel insight into the sex-specific effect of glycogen in survival and aging and how differences in metabolic processes could contribute to sex-specific traits.
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Affiliation(s)
- Deepashree Sheshadri
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Akanksha Onkar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
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Pondrelli F, Muccioli L, Licchetta L, Mostacci B, Zenesini C, Tinuper P, Vignatelli L, Bisulli F. Natural history of Lafora disease: a prognostic systematic review and individual participant data meta-analysis. Orphanet J Rare Dis 2021; 16:362. [PMID: 34399803 PMCID: PMC8365996 DOI: 10.1186/s13023-021-01989-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 07/29/2021] [Indexed: 12/29/2022] Open
Abstract
Background Lafora disease (LD) is a rare fatal autosomal recessive form of progressive myoclonus epilepsy. It affects previously healthy children or adolescents, causing pharmacoresistant epilepsy, myoclonus and severe psychomotor deterioration. This work aims to describe the clinical course of LD and identify predictors of outcome by means of a prognostic systematic review with individual participant data meta-analysis. Methods A search was conducted on MEDLINE and Embase with no restrictions on publication date. Only studies reporting genetically confirmed LD cases were included. Kaplan–Meier estimate was used to assess probability of death and loss of autonomy. Univariable and multivariable Cox regression models with mixed effects (clustered survival data) were performed to evaluate prognostic factors. Results Seventy-three papers describing 298 genetically confirmed LD cases were selected. Mean age at disease onset was 13.4 years (SD 3.7), with 9.1% aged ≥ 18 years. Overall survival rates in 272 cases were 93% [95% CI 89–96] at 5 years, 62% [95% CI 54–69] at 10 years and 57% [95% CI 49–65] at 15 years. Median survival time was 11 years. The probability of loss of autonomy in 110 cases was 45% [95% CI 36–55] at 5 years, 75% [95% CI 66–84] at 10 years, and 83% [95% CI 74–90] at 15 years. Median loss of autonomy time was 6 years. Asian origin and age at onset < 18 years emerged as negative prognostic factors, while type of mutated gene and symptoms at onset were not related to survival or disability. Conclusions This study documented that half of patients survived at least 11 years. The notion of actual survival rate and prognostic factors is crucial to design studies on the effectiveness of upcoming new disease-modifying therapies.
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Affiliation(s)
- Federica Pondrelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Lorenzo Muccioli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Laura Licchetta
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy
| | - Barbara Mostacci
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy
| | - Corrado Zenesini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy
| | - Paolo Tinuper
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy.,IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy
| | - Luca Vignatelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy
| | - Francesca Bisulli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy. .,IRCCS Istituto delle Scienze Neurologiche di Bologna, Full Member of the ERN EpiCARE, Bologna, Italy.
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12
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Vrachnis N, Papoulidis I, Vrachnis D, Siomou E, Antonakopoulos N, Oikonomou S, Zygouris D, Loukas N, Iliodromiti Z, Pavlidou E, Thomaidis L, Manolakos E. Partial deletion of chromosome 6p causing developmental delay and mild dysmorphisms in a child: molecular and developmental investigation and literature search. Mol Cytogenet 2021; 14:39. [PMID: 34303382 PMCID: PMC8310580 DOI: 10.1186/s13039-021-00557-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 07/06/2021] [Indexed: 11/28/2022] Open
Abstract
Background The interstitial 6p22.3 deletions concern rare chromosomal events affecting numerous aspects of both physical and mental development. The syndrome is characterized by partial deletion of chromosome 6, which may arise in a number of ways. Case presentation We report a 2.8-year old boy presenting with developmental delay and mild dysmorphisms. High-resolution oligonucleotide microarray analysis revealed with high precision a 2.5 Mb interstitial 6p deletion in the 6p22.3 region which encompasses 13 genes. Conclusions Identification and in-depth analysis of cases presenting with mild features of the syndrome will sharpen our understanding of the genetic spectrum of the 6p22.3 deletion.
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Affiliation(s)
- Nikolaos Vrachnis
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens, Medical School, Attikon Hospital, Athens, GR, Greece. .,Research Centre in Obstetrics and Gynecology, HSOGE, Athens, Greece. .,Vascular Biology, Molecular and Clinical Sciences Research Institute, St George's University of London, London, UK.
| | - Ioannis Papoulidis
- Access To Genome P.C., Clinical Laboratory Genetics, Athens-Thessaloniki, Greece
| | - Dionysios Vrachnis
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Medical School, Alexandra Hospital, Athens, Greece
| | - Elisavet Siomou
- Access To Genome P.C., Clinical Laboratory Genetics, Athens-Thessaloniki, Greece
| | - Nikolaos Antonakopoulos
- Third Department of Obstetrics and Gynecology, National and Kapodistrian University of Athens, Medical School, Attikon Hospital, Athens, GR, Greece.,Research Centre in Obstetrics and Gynecology, HSOGE, Athens, Greece
| | - Stavroula Oikonomou
- Second Department of Pediatrics, Aglaia Kyriakou Hospital, Medical School, National & Kapodistrian University of Athens, Athens, Greece
| | | | - Nikolaos Loukas
- Department of Gynecology, General Hospital of Athens "G. Gennimatas", Athens, Greece
| | - Zoi Iliodromiti
- Neonatal Department, National and Kapodistrian University of Athens Medical School, Aretaieio Hospital, Athens, Greece
| | - Efterpi Pavlidou
- Department of Pediatrics, School of Medicine, Aristotle University of Thessaloniki, University General Hospital AHEPA, Thessaloniki, Greece
| | - Loretta Thomaidis
- Second Department of Pediatrics, Aglaia Kyriakou Hospital, Medical School, National & Kapodistrian University of Athens, Athens, Greece
| | - Emmanouil Manolakos
- Access To Genome P.C., Clinical Laboratory Genetics, Athens-Thessaloniki, Greece
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13
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Mari L, Comero G, Mueller E, Kuehnlein P, Kehl A. NHLRC1 homozygous dodecamer expansion in a Newfoundland dog with Lafora disease. J Small Anim Pract 2021; 62:1030-1032. [PMID: 34263924 DOI: 10.1111/jsap.13396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/09/2021] [Accepted: 06/10/2021] [Indexed: 10/20/2022]
Abstract
Lafora disease is a genetic disease caused, in humans, by mutations in EPM2A and NHLRC1 genes, resulting in accumulation of polyglucosan bodies within neurons. Affected subjects present progressive neurological signs characterised primarily by myoclonic epilepsy. In dogs, Lafora disease has been described mainly in miniature wire-haired Dachshunds, where a dodecamer expansion in NHLRC1 gene has been identified. The same mutation has then been detected in the Basset Hound, Beagle, Chihuahua and Pembroke Welsh Corgi breeds. This is the first case of a Newfoundland dog with myoclonic epilepsy diagnosed with Lafora disease based on confirmed dodecamer expansion in the NHLRC1 gene. Lafora disease is being progressively recognised in different unrelated breeds suggesting a wider distribution in the canine population than previously thought.
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Affiliation(s)
- L Mari
- Neurology and Neurosurgery Department, Istituto Veterinario di Novara, Granozzo con Monticello, 28060, Italy
| | - G Comero
- Neurology and Neurosurgery Department, Istituto Veterinario di Novara, Granozzo con Monticello, 28060, Italy
| | - E Mueller
- Laboklin GmbH&Co. KG, Bad Kissingen, 97688, Germany
| | - P Kuehnlein
- Laboklin GmbH&Co. KG, Bad Kissingen, 97688, Germany
| | - A Kehl
- Laboklin GmbH&Co. KG, Bad Kissingen, 97688, Germany
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14
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Obara K, Abe E, Toyoshima I. Frontal Hypoperfusion and the Effectiveness of Perampanel in Long-Lived Patient with Lafora Disease. Case Rep Neurol 2021; 13:211-217. [PMID: 33976658 PMCID: PMC8077499 DOI: 10.1159/000514243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/29/2020] [Indexed: 11/19/2022] Open
Abstract
We report a long-lived patient with Lafora disease (LD). A 34-year-old woman experienced onset of seizures at the age of 11 years. She was bedridden in her early twenties due to frequent generalized tonic-clonic seizures, myoclonus, and progressive mental deterioration. Her seizures occurred all the time despite administration of multiple anticonvulsants at high doses. At the age of 31, she started perampanel, which resulted in reduction of anticonvulsants after her visible myoclonus and convulsions disappeared. Brain magnetic resonance imaging showed marked cerebral and cerebellar atrophy, and single-photon emission computed tomography using N-isopropyl-p-[123I] iodoamphetamine (IMP-SPECT) revealed significant hypoperfusion of the frontal lobe and cerebellum. We identified a W219R homozygous mutation in exon 1 of the NHLRC1 gene. Because perampanel may not only control seizures but also prevent mental deterioration in LD, we propose that perampanel should be administered from the early stage of LD.
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Affiliation(s)
- Koji Obara
- Department of Neurology, Akita National Hospital, National Hospital Organization, Yurihonjo, Japan
| | - Erika Abe
- Department of Neurology, Akita National Hospital, National Hospital Organization, Yurihonjo, Japan
| | - Itaru Toyoshima
- Department of Neurology, Akita National Hospital, National Hospital Organization, Yurihonjo, Japan
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15
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Sinha P, Verma B, Ganesh S. Trehalose Ameliorates Seizure Susceptibility in Lafora Disease Mouse Models by Suppressing Neuroinflammation and Endoplasmic Reticulum Stress. Mol Neurobiol 2021; 58:1088-1101. [PMID: 33094475 DOI: 10.1007/s12035-020-02170-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 10/14/2020] [Indexed: 12/20/2022]
Abstract
Lafora disease (LD) is one of the progressive and fatal forms of a neurodegenerative disorder and is characterized by teenage-onset myoclonic seizures. Neuropathological changes in LD include the formation of abnormal glycogen as Lafora bodies, gliosis, and neuroinflammation. LD is caused by defects in the gene coding for phosphatase (laforin) or ubiquitin ligase (malin). Mouse models of LD, developed by targeted disruption of these two genes, develop most symptoms of LD and show increased susceptibility to induced seizures. Studies on mouse models also suggest that defective autophagy might contribute to LD etiology. In an attempt to understand the specific role of autophagy in LD pathogenesis, in this study, we fed LD animals with trehalose, an inducer of autophagy, for 3 months and looked at its effect on the neuropathology and seizure susceptibility. We demonstrate here that trehalose ameliorates gliosis, neuroinflammation, and endoplasmic reticulum stress and reduces susceptibility to induced seizures in LD animals. However, trehalose did not affect the formation of Lafora bodies, suggesting the epileptic phenotype in LD could be either secondary to or independent of Lafora bodies. Taken together, our results suggest that autophagy inducers can be considered as potential therapeutic molecules for Lafora disease.
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Affiliation(s)
- Priyanka Sinha
- Department of Biological Sciences & Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Bhupender Verma
- Department of Biological Sciences & Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Subramaniam Ganesh
- Department of Biological Sciences & Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
- The Mehta Family Centre for Engineering in Medicine, Indian Institute of Technology Kanpur, Kanpur, India.
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16
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Sinha P, Verma B, Ganesh S. Dexamethasone-induced activation of heat shock response ameliorates seizure susceptibility and neuroinflammation in mouse models of Lafora disease. Exp Neurol 2021; 340:113656. [PMID: 33639210 DOI: 10.1016/j.expneurol.2021.113656] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 01/26/2021] [Accepted: 02/21/2021] [Indexed: 11/29/2022]
Abstract
Heat shock response (HSR) is a conserved cytoprotective pathway controlled by the master transcriptional regulator, the heat shock factor 1 (HSF1), that activates the expression of heat shock proteins (HSPs). HSPs, as chaperones, play essential roles in minimizing stress-induced damages and restoring proteostasis. Therefore, compromised HSR is thought to contribute to neurodegenerative disorders. Lafora disease (LD) is a fatal form of neurodegenerative disorder characterized by the accumulation of abnormal glycogen as Lafora bodies in neurons and other tissues. The symptoms of LD include progressive myoclonus epilepsy, dementia, and cognitive deficits. LD is caused by the defects in the gene coding laforin phosphatase or the malin ubiquitin ligase. Laforin and malin are known to work upstream of HSF1 and are essential for the activation of HSR. Herein, we show that mice deficient for laforin or malin show reduced levels of HSF1 and their targets in their brain tissues, suggesting compromised HSR; this could contribute to the neuropathology in LD. Intriguingly, treatment of LD animals with dexamethasone, a synthetic glucocorticoid analogue, partially restored the levels of HSF1 and its targets. Dexamethasone treatment was also able to ameliorate the neuroinflammation and susceptibility to induced seizures in the LD animals. However, dexamethasone treatment did not show a significant effect on Lafora bodies or autophagy defects. Taken together, the present study establishes a role for HSR in seizure susceptibility and neuroinflammation and dexamethasone as a potential antiepileptic agent, suitable for further studies in LD.
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Affiliation(s)
- Priyanka Sinha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Bhupender Verma
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India.
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17
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Taneja K, Ganesh S. Dendritic spine abnormalities correlate with behavioral and cognitive deficits in mouse models of Lafora disease. J Comp Neurol 2020; 529:1099-1120. [DOI: 10.1002/cne.25006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 06/20/2020] [Accepted: 08/04/2020] [Indexed: 01/03/2023]
Affiliation(s)
- Komal Taneja
- Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur Kanpur Uttar Pradesh India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur Kanpur Uttar Pradesh India
- The Mehta Family Centre for Engineering in Medicine Indian Institute of Technology Kanpur Kanpur Uttar Pradesh India
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18
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Abstract
Macroautophagy/autophagy is an intracellular degradative pathway that is often induced as a pro-survival process for cells under stress. A few recent reports establish the role of the glycogen metabolic pathway in neuronal cell survival in conditions such as oxidative stress and hypoxia, and the possible link between glycogen synthesis and autophagy induction. This commentary highlights the emerging role of GYS (glycogen synthase) in neuronal autophagy and stress response.
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Affiliation(s)
- Akanksha Onkar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur , Kanpur, India
| | - Deepashree Sheshadri
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur , Kanpur, India
| | - Subramaniam Ganesh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur , Kanpur, India
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19
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Abstract
The progressive myoclonic epilepsies (PMEs) represent a rare but devastating group of syndromes characterized by epileptic myoclonus, typically action-induced seizures, neurological regression, medically refractory epilepsy, and a variety of other signs and symptoms depending on the specific syndrome. Most of the PMEs begin in children who are developing as expected, with the onset of the disorder heralded by myoclonic and other seizure types. The conditions are considerably heterogenous, but medical intractability to epilepsy, particularly myoclonic seizures, is a core feature. With the increasing use of molecular genetic techniques, mutations and their abnormal protein products are being delineated, providing a basis for disease-based therapy. However, genetic and enzyme replacement or substrate removal are in the nascent stage, and the primary therapy is through antiepileptic drugs. Epilepsy in children with progressive myoclonic seizures is notoriously difficult to treat. The disorder is rare, so few double-blinded, placebo-controlled trials have been conducted in PME, and drugs are chosen based on small open-label trials or extrapolation of data from drug trials of other syndromes with myoclonic seizures. This review discusses the major PME syndromes and their neurogenetic basis, pathophysiological underpinning, electroencephalographic features, and currently available treatments.
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Affiliation(s)
- Gregory L Holmes
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont College of Medicine, Stafford Hall, 118C, Burlington, VT, 05405, USA.
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