1
|
Chan KL, Panatpur A, Messahel S, Dahshi H, Johnson T, Henning A, Ren J, Minassian BA. 1H and 31P magnetic resonance spectroscopy reveals potential pathogenic and biomarker metabolite alterations in Lafora disease. Brain Commun 2024; 6:fcae104. [PMID: 38585668 PMCID: PMC10998360 DOI: 10.1093/braincomms/fcae104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/19/2024] [Accepted: 03/22/2024] [Indexed: 04/09/2024] Open
Abstract
Lafora disease is a fatal teenage-onset progressive myoclonus epilepsy and neurodegenerative disease associated with polyglucosan bodies. Polyglucosans are long-branched and as a result precipitation- and aggregation-prone glycogen. In mouse models, downregulation of glycogen synthase, the enzyme that elongates glycogen branches, prevents polyglucosan formation and rescues Lafora disease. Mouse work, however, has not yet revealed the mechanisms of polyglucosan generation, and few in vivo human studies have been performed. Here, non-invasive in vivo magnetic resonance spectroscopy (1H and 31P) was applied to test scan feasibility and assess neurotransmitter balance and energy metabolism in Lafora disease towards a better understanding of pathogenesis. Macromolecule-suppressed gamma-aminobutyric acid (GABA)-edited 1H magnetic resonance spectroscopy and 31P magnetic resonance spectroscopy at 3 and 7 tesla, respectively, were performed in 4 Lafora disease patients and a total of 21 healthy controls (12 for the 1H magnetic resonance spectroscopy and 9 for the 31PMRS). Spectra were processed using in-house software and fit to extract metabolite concentrations. From the 1H spectra, we found 33% lower GABA concentrations (P = 0.013), 34% higher glutamate + glutamine concentrations (P = 0.011) and 24% lower N-acetylaspartate concentrations (P = 0.0043) in Lafora disease patients compared with controls. From the 31P spectra, we found 34% higher phosphoethanolamine concentrations (P = 0.016), 23% lower nicotinamide adenine dinucleotide concentrations (P = 0.003), 50% higher uridine diphosphate glucose concentrations (P = 0.004) and 225% higher glucose 6-phosphate concentrations in Lafora disease patients versus controls (P = 0.004). Uridine diphosphate glucose is the substrate of glycogen synthase, and glucose 6-phosphate is its extremely potent allosteric activator. The observed elevated uridine diphosphate glucose and glucose 6-phosphate levels are expected to hyperactivate glycogen synthase and may underlie the generation of polyglucosans in Lafora disease. The increased glutamate + glutamine and reduced GABA indicate altered neurotransmission and energy metabolism, which may contribute to the disease's intractable epilepsy. These results suggest a possible basis of polyglucosan formation and potential contributions to the epilepsy of Lafora disease. If confirmed in larger human and animal model studies, measurements of the dysregulated metabolites by magnetic resonance spectroscopy could be developed into non-invasive biomarkers for clinical trials.
Collapse
Affiliation(s)
- Kimberly L Chan
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Aparna Panatpur
- Department of Pediatrics, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Souad Messahel
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hamza Dahshi
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Talon Johnson
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Anke Henning
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jimin Ren
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Berge A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| |
Collapse
|
2
|
Donohue KJ, Fitzsimmons B, Bruntz RC, Markussen KH, Young LEA, Clarke HA, Coburn PT, Griffith LE, Sanders W, Klier J, Burke SN, Maurer AP, Minassian BA, Sun RC, Kordasiewisz HB, Gentry MS. Gys1 Antisense Therapy Prevents Disease-Driving Aggregates and Epileptiform Discharges in a Lafora Disease Mouse Model. Neurotherapeutics 2023; 20:1808-1819. [PMID: 37700152 PMCID: PMC10684475 DOI: 10.1007/s13311-023-01434-9] [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] [Accepted: 08/22/2023] [Indexed: 09/14/2023] Open
Abstract
Patients with Lafora disease have a mutation in EPM2A or EPM2B, resulting in dysregulation of glycogen metabolism throughout the body and aberrant glycogen molecules that aggregate into Lafora bodies. Lafora bodies are particularly damaging in the brain, where the aggregation drives seizures with increasing severity and frequency, coupled with neurodegeneration. Previous work employed mouse genetic models to reduce glycogen synthesis by approximately 50%, and this strategy significantly reduced Lafora body formation and disease phenotypes. Therefore, an antisense oligonucleotide (ASO) was developed to reduce glycogen synthesis in the brain by targeting glycogen synthase 1 (Gys1). To test the distribution and efficacy of this drug, the Gys1-ASO was administered to Epm2b-/- mice via intracerebroventricular administration at 4, 7, and 10 months. The mice were then sacrificed at 13 months and their brains analyzed for Gys1 expression, glycogen aggregation, and neuronal excitability. The mice treated with Gys1-ASO exhibited decreased Gys1 protein levels, decreased glycogen aggregation, and reduced epileptiform discharges compared to untreated Epm2b-/- mice. This work provides proof of concept that a Gys1-ASO halts disease progression of EPM2B mutations of Lafora disease.
Collapse
Affiliation(s)
- Katherine J Donohue
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Bethany Fitzsimmons
- Department of Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | - Ronald C Bruntz
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Kia H Markussen
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Lyndsay E A Young
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Harrison A Clarke
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, 32610, USA
| | - Peyton T Coburn
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Laiken E Griffith
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - William Sanders
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Jack Klier
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Sara N Burke
- Department of Neuroscience and Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL, 32610, USA
| | - Andrew P Maurer
- Department of Neuroscience and Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL, 32610, USA
| | - Berge A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Ramon C Sun
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, 32610, USA
| | - Holly B Kordasiewisz
- Department of Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | - Matthew S Gentry
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, 32610, USA.
| |
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Duran J. Role of Astrocytes in the Pathophysiology of Lafora Disease and Other Glycogen Storage Disorders. Cells 2023; 12:cells12050722. [PMID: 36899857 PMCID: PMC10000527 DOI: 10.3390/cells12050722] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/05/2023] [Accepted: 02/22/2023] [Indexed: 03/12/2023] Open
Abstract
Lafora disease is a rare disorder caused by loss of function mutations in either the EPM2A or NHLRC1 gene. The initial symptoms of this condition are most commonly epileptic seizures, but the disease progresses rapidly with dementia, neuropsychiatric symptoms, and cognitive deterioration and has a fatal outcome within 5-10 years after onset. The hallmark of the disease is the accumulation of poorly branched glycogen in the form of aggregates known as Lafora bodies in the brain and other tissues. Several reports have demonstrated that the accumulation of this abnormal glycogen underlies all the pathologic traits of the disease. For decades, Lafora bodies were thought to accumulate exclusively in neurons. However, it was recently identified that most of these glycogen aggregates are present in astrocytes. Importantly, astrocytic Lafora bodies have been shown to contribute to pathology in Lafora disease. These results identify a primary role of astrocytes in the pathophysiology of Lafora disease and have important implications for other conditions in which glycogen abnormally accumulates in astrocytes, such as Adult Polyglucosan Body disease and the buildup of Corpora amylacea in aged brains.
Collapse
Affiliation(s)
- Jordi Duran
- Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), 08017 Barcelona, Spain;
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| |
Collapse
|
5
|
Daglas M, Truong PH, Miles LQ, Juan SMA, Rao SS, Adlard PA. Deferiprone attenuates neuropathology and improves outcome following traumatic brain injury. Br J Pharmacol 2023; 180:214-234. [PMID: 36102035 DOI: 10.1111/bph.15950] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 08/27/2022] [Accepted: 09/08/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Traumatic brain injury (TBI) remains a leading cause of mortality and morbidity in young adults. The role of iron in potentiating neurodegeneration following TBI has gained recent interest as iron deposition has been detected in the injured brain in the weeks to months post-TBI, in both the preclinical and clinical setting. A failure in iron homeostasis can lead to oxidative stress, inflammation and excitotoxicity; and whether this is a cause or consequence of the long-term effects of TBI remains unknown. EXPERIMENTAL APPROACH We investigated the role of iron and the effect of therapeutic intervention using a brain-permeable iron chelator, deferiprone, in a controlled cortical impact mouse model of TBI. An extensive assessment of cognitive, motor and anxiety/depressive outcome measures were examined, and neuropathological and biochemical changes, over a 3-month period post-TBI. KEY RESULTS Lesion volume was significantly reduced at 3 months, which was preceded by a reduction in astrogliosis, microglia/macrophages and preservation of neurons in the injured brain at 2 weeks and/or 1 month post-TBI in mice receiving oral deferiprone. Deferiprone treatment showed significant improvements in neurological severity scores, locomotor/gait performance and cognitive function, and attenuated anxiety-like symptoms post-TBI. Deferiprone reduced iron levels, lipid peroxidation/oxidative stress and altered expression of neurotrophins in the injured brain over this period. CONCLUSION AND IMPLICATIONS Our findings support a detrimental role of iron in the injured brain and suggest that deferiprone (or similar iron chelators) may be promising therapeutic approaches to improve survival, functional outcomes and quality of life following TBI.
Collapse
Affiliation(s)
- Maria Daglas
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Phan H Truong
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Linh Q Miles
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Sydney M A Juan
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Shalini S Rao
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| | - Paul A Adlard
- Synaptic Neurobiology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia
| |
Collapse
|
6
|
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.
Collapse
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.)
| |
Collapse
|
7
|
Mollá B, Heredia M, Campos Á, Sanz P. Pharmacological Modulation of Glutamatergic and Neuroinflammatory Pathways in a Lafora Disease Mouse Model. Mol Neurobiol 2022; 59:6018-6032. [PMID: 35835895 PMCID: PMC9463199 DOI: 10.1007/s12035-022-02956-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022]
Abstract
Lafora disease (LD) is a fatal rare neurodegenerative disorder that affects young adolescents and has no treatment yet. The hallmark of LD is the presence of polyglucosan inclusions (PGs), called Lafora bodies (LBs), in the brain and peripheral tissues. LD is caused by mutations in either EPM2A or EPM2B genes, which, respectively, encode laforin, a glucan phosphatase, and malin, an E3-ubiquitin ligase, with identical clinical features. LD knockout mouse models (Epm2a - / - and Epm2b - / -) recapitulate PG body accumulation, as in the human pathology, and display alterations in glutamatergic transmission and neuroinflammatory pathways in the brain. In this work, we show the results of four pre-clinical trials based on the modulation of glutamatergic transmission (riluzole and memantine) and anti-neuroinflammatory interventions (resveratrol and minocycline) as therapeutical strategies in an Epm2b - / - mouse model. Drugs were administered in mice from 3 to 5 months of age, corresponding to early stage of the disease, and we evaluated the beneficial effect of the drugs by in vivo behavioral phenotyping and ex vivo histopathological brain analyses. The behavioral assessment was based on a battery of anxiety, cognitive, and neurodegenerative tests and the histopathological analyses included a panel of markers regarding PG accumulation, astrogliosis, and microgliosis. Overall, the outcome of ameliorating the excessive glutamatergic neurotransmission present in Epm2b - / - mice by memantine displayed therapeutic effectiveness at the behavioral levels. Modulation of neuroinflammation by resveratrol and minocycline also showed beneficial effects at the behavioral level. Therefore, our study suggests that both therapeutical strategies could be beneficial for the treatment of LD patients. A mouse model of Lafora disease (Epm2b-/-) was used to check the putative beneficial effect of different drugs aimed to ameliorate the alterations in glutamatergic transmission and/or neuroinflammation present in the model. Drugs in blue gave a more positive outcome than the rest.
Collapse
Affiliation(s)
- Belén Mollá
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Miguel Heredia
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Ángela Campos
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Valencia, Spain
| | - Pascual Sanz
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Jaime Roig 11, 46010 Valencia, Spain
| |
Collapse
|
8
|
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.
Collapse
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.
| |
Collapse
|
9
|
Gumusgoz E, Kasiri S, Guisso DR, Wu J, Dear M, Verhalen B, Minassian BA. AAV-Mediated Artificial miRNA Reduces Pathogenic Polyglucosan Bodies and Neuroinflammation in Adult Polyglucosan Body and Lafora Disease Mouse Models. Neurotherapeutics 2022; 19:982-993. [PMID: 35347645 PMCID: PMC9294094 DOI: 10.1007/s13311-022-01218-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 11/28/2022] Open
Abstract
Adult polyglucosan body disease (APBD) and Lafora disease (LD) are autosomal recessive glycogen storage neurological disorders. APBD is caused by mutations in the glycogen branching enzyme (GBE1) gene and is characterized by progressive upper and lower motor neuron dysfunction and premature death. LD is a fatal progressive myoclonus epilepsy caused by loss of function mutations in the EPM2A or EPM2B gene. These clinically distinct neurogenetic diseases share a common pathology. This consists of time-dependent formation, precipitation, and accumulation of an abnormal form of glycogen (polyglucosan) into gradually enlarging inclusions, polyglucosan bodies (PBs) in ever-increasing numbers of neurons and astrocytes. The growth and spread of PBs are followed by astrogliosis, microgliosis, and neurodegeneration. The key defect in polyglucosans is that their glucan branches are longer than those of normal glycogen, which prevents them from remaining in solution. Since the lengths of glycogen branches are determined by the enzyme glycogen synthase, we hypothesized that downregulating this enzyme could prevent or hinder the generation of the pathogenic PBs. Here, we pursued an adeno-associated virus vector (AAV) mediated RNA-interference (RNAi) strategy. This approach resulted in approximately 15% reduction of glycogen synthase mRNA and an approximately 40% reduction of PBs across the brain in the APBD and both LD mouse models. This was accompanied by improvements in early neuroinflammatory markers of disease. This work represents proof of principle toward developing a single lifetime dose therapy for two fatal neurological diseases: APBD and LD. The approach is likely applicable to other severe and common diseases of glycogen storage.
Collapse
Affiliation(s)
- Emrah Gumusgoz
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Sahba Kasiri
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Dikran R Guisso
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Jun Wu
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Matthew Dear
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Brandy Verhalen
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
- Present affiliation: Corteva Agriscience, Johnston, IA, 50131, USA
| | - Berge A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.
| |
Collapse
|
10
|
Yokoi R, Shigemoto-Kuroda T, Matsuda N, Odawara A, Suzuki I. Electrophysiological responses to seizurogenic compounds dependent on E/I balance in human iPSC-derived cortical neural networks. J Pharmacol Sci 2022; 148:267-278. [DOI: 10.1016/j.jphs.2021.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/18/2021] [Accepted: 12/27/2021] [Indexed: 10/19/2022] Open
|
11
|
Mitra S, Gumusgoz E, Minassian BA. Lafora disease: Current biology and therapeutic approaches. Rev Neurol (Paris) 2021; 178:315-325. [PMID: 34301405 DOI: 10.1016/j.neurol.2021.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/21/2021] [Accepted: 06/16/2021] [Indexed: 12/19/2022]
Abstract
The ubiquitin system impacts most cellular processes and is altered in numerous neurodegenerative diseases. However, little is known about its role in neurodegenerative diseases due to disturbances of glycogen metabolism such as Lafora disease (LD). In LD, insufficiently branched and long-chained glycogen forms and precipitates into insoluble polyglucosan bodies (Lafora bodies), which drive neuroinflammation, neurodegeneration and epilepsy. LD is caused by mutations in the gene encoding the glycogen phosphatase laforin or the gene coding for the laforin interacting partner ubiquitin E3 ligase malin. The role of the malin-laforin complex in regulating glycogen structure remains with full of gaps. In this review we bring together the disparate body of data on these two proteins and propose a mechanistic hypothesis of the disease in which malin-laforin's role to monitor and prevent over-elongation of glycogen branch chains, which drive glycogen molecules to precipitate and accumulate into Lafora bodies. We also review proposed connections between Lafora bodies and the ensuing neuroinflammation, neurodegeneration and intractable epilepsy. Finally, we review the exciting activities in developing therapies for Lafora disease based on replacing the missing genes, slowing the enzyme - glycogen synthase - that over-elongates glycogen branches, and introducing enzymes that can digest Lafora bodies. Much more work is needed to fill the gaps in glycogen metabolism in which laforin and malin operate. However, knowledge appears already adequate to advance disease course altering therapies for this catastrophic fatal disease.
Collapse
Affiliation(s)
- S Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - E Gumusgoz
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - B A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
| |
Collapse
|
12
|
Mollá B, Heredia M, Sanz P. Modulators of Neuroinflammation Have a Beneficial Effect in a Lafora Disease Mouse Model. Mol Neurobiol 2021; 58:2508-2522. [PMID: 33447969 PMCID: PMC8167455 DOI: 10.1007/s12035-021-02285-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/07/2021] [Indexed: 12/22/2022]
Abstract
Lafora disease (LD; OMIM#274780) is a fatal rare neurodegenerative disorder characterized by generalized epileptic seizures and the presence of polyglucosan inclusions (PGs), called Lafora bodies (LBs), typically in the brain. LD is caused by mutations in two genes EPM2A or EPM2B, which encode respectively laforin, a glucan phosphatase, and malin, an E3-ubiquitin ligase. Much remains unknown about the molecular bases of LD and, unfortunately, appropriate treatment is still missing; therefore patients die within 10 years from the onset of the disease. Recently, we have identified neuroinflammation as one of the initial determinants in LD. In this work, we have investigated anti-inflammatory treatments as potential therapies in LD. With this aim, we have performed a preclinical study in an Epm2b-/- mouse model with propranolol, a β-adrenergic antagonist, and epigallocatechin gallate (EGCG), an antioxidant from green tea extract, both of which displaying additional anti-inflammatory properties. In vivo motor and cognitive behavioral tests and ex vivo histopathological brain analyses were used as parameters to assess the therapeutic potential of propranolol and EGCG. After 2 months of treatment, we observed an improvement not only in attention defects but also in neuronal disorganization, astrogliosis, and microgliosis present in the hippocampus of Epm2b-/- mice. In general, propranolol intervention was more effective than EGCG in preventing the appearance of astrocyte and microglia reactivity. In summary, our results confirm the potential therapeutic effectiveness of the modulators of inflammation as novel treatments in Lafora disease.
Collapse
Affiliation(s)
- Belén Mollá
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Consejo Superior de Investigaciones Científicas, Jaime Roig 11, 46010, Valencia, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010, Valencia, Spain.
| | - Miguel Heredia
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Consejo Superior de Investigaciones Científicas, Jaime Roig 11, 46010, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010, Valencia, Spain
| | - Pascual Sanz
- Laboratory of Nutrient Signaling, Institute of Biomedicine of Valencia (CSIC), Consejo Superior de Investigaciones Científicas, Jaime Roig 11, 46010, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010, Valencia, Spain
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Suzuki I. [Approach to drug efficacy and safety assessment based on functions of a human iPSC-derived neuronal network]. Nihon Yakurigaku Zasshi 2020; 155:289-294. [PMID: 32879166 DOI: 10.1254/fpj.20031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Development of an in vitro drug efficacy and safety assessment based on the function of the neural network is required in preclinical studies. A microelectrode array (MEA), which can simultaneously measure the electrical activity of a human induced pluripotent stem cell-derived neural network at multiple points, is an effective assay system. In this study, we focused on seizure liability and clarified the responsiveness to seizure-positive compounds depending on the excitatory and inhibitory balance (E/I balance) of each evaluation sample. In addition, it has been shown that multivariate analysis and AI analysis methods are effective for detecting toxicity and predicting drug mechanisms of action. The future challenge is to approach in vitro-to-in vivo extrapolation (IVIVE) for in vitro assessment. An assessment using brain organoids and low-frequency component analysis, in which enable comparison with in vivo ECoG are effective approaches to IVIVE. MEA can be applied to the central nervous system and the peripheral nervous system; therefore, MEA is also expected to become a highly useful assessment tool for peripheral neuropathy.
Collapse
Affiliation(s)
- Ikuro Suzuki
- Department of Electronics, Graduate School of Engineering, Tohoku Institute of Technology
| |
Collapse
|
15
|
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
| |
Collapse
|
16
|
Silvennoinen K, Balestrini S, Rothwell JC, Sisodiya SM. Transcranial magnetic stimulation as a tool to understand genetic conditions associated with epilepsy. Epilepsia 2020; 61:1818-1839. [PMID: 32783192 PMCID: PMC8432162 DOI: 10.1111/epi.16634] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 12/30/2022]
Abstract
Advances in genetics may enable a deeper understanding of disease mechanisms and promote a shift to more personalised medicine in the epilepsies. At present, understanding of consequences of genetic variants mainly relies on preclinical functional work; tools for acquiring similar data from the living human brain are needed. Transcranial magnetic stimulation (TMS), in particular paired-pulse TMS protocols which depend on the function of cortical GABAergic interneuron networks, has the potential to become such a tool. For this report, we identified and reviewed 23 publications on TMS studies of cortical excitability and inhibition in 15 different genes or conditions relevant to epilepsy. Reduced short-interval intracortical inhibition (SICI) and reduced cortical silent period (CSP) duration were the most commonly reported findings, suggesting abnormal GABAA - (SICI) or GABAB ergic (CSP) signalling. For several conditions, these findings are plausible based on established evidence of involvement of the GABAergic system; for some others, they may inform future research around such mechanisms. Challenges of TMS include lack of complete understanding of the neural underpinnings of the measures used: hypotheses and analyses should be based on existing clinical and preclinical data. Further pitfalls include gathering sufficient numbers of participants, and the effect of confounding factors, especially medications. TMS-EEG is a unique perturbational technique to study the intrinsic properties of the cortex with excellent temporal resolution; while it has the potential to provide further information of use in interpreting effects of genetic variants, currently the links between measures and neurophysiology are less established. Despite these challenges, TMS is a tool with potential for elucidating the system-level in vivo functional consequences of genetic variants in people carrying genetic changes of interest, providing unique insights.
Collapse
Affiliation(s)
- Katri Silvennoinen
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Chalfont St. Peter, UK
| | - Simona Balestrini
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Chalfont St. Peter, UK
| | - John C Rothwell
- Sobell Department of Motor Neuroscience and Movement Disorders, Department of UCL Queen Square, Institute of Neurology, London, UK
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Chalfont St. Peter, UK
| |
Collapse
|
17
|
Shirakawa T, Suzuki I. Approach to Neurotoxicity using Human iPSC Neurons: Consortium for Safety Assessment using Human iPS Cells. Curr Pharm Biotechnol 2020; 21:780-786. [DOI: 10.2174/1389201020666191129103730] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/27/2019] [Accepted: 11/03/2019] [Indexed: 01/05/2023]
Abstract
Neurotoxicity, as well as cardiotoxicity and hepatotoxicity, resulting from administration of
a test article is considered a major adverse effect both pre-clinically and clinically. Among the different
types of neurotoxicity occurring during the drug development process, seizure is one of the most serious
one. Seizure occurrence is usually assessed using in vivo animal models, the Functional Observational
Battery, the Irwin test or electroencephalograms. In in vitro studies, a number of assessments can
be performed using animal organs/cells. Interestingly, recent developments in stem cell biology, especially
the development of Human-Induced Pluripotent Stem (iPS) cells, are enabling the assessment of
neurotoxicity in human iPS cell-derived neurons. Further, a Multi-Electrode Array (MEA) using rodent
neurons is a useful tool for identifying seizure-inducing compounds. The Consortium for Safety Assessment
using Human iPS Cells (CSAHi; http://csahi.org/en/) was established in 2013 by the Japan
Pharmaceutical Manufacturers Association (JPMA) to verify the application of human iPS cell-derived
neuronal cells to drug safety evaluation. The Neuro Team of CSAHi has been attempting to evaluate the
seizure risk of compounds using the MEA platform. Here, we review the current status of neurotoxicity
and recent work, including problems related to the use of the MEA assay with human iPS neuronal
cell-derived neurons, and future developments.
Collapse
Affiliation(s)
- Takafumi Shirakawa
- Consortium for Safety Assessment using Human iPS Cells (CSAHi), Neuro Team, Japan
| | - Ikuro Suzuki
- Consortium for Safety Assessment using Human iPS Cells (CSAHi), Neuro Team, Japan
| |
Collapse
|
18
|
Tang B, Frasinyuk MS, Chikwana VM, Mahalingan KK, Morgan CA, Segvich DM, Bondarenko SP, Mrug GP, Wyrebek P, Watt DS, DePaoli-Roach AA, Roach PJ, Hurley TD. Discovery and Development of Small-Molecule Inhibitors of Glycogen Synthase. J Med Chem 2020; 63:3538-3551. [PMID: 32134266 DOI: 10.1021/acs.jmedchem.9b01851] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The overaccumulation of glycogen appears as a hallmark in various glycogen storage diseases (GSDs), including Pompe, Cori, Andersen, and Lafora disease. Accumulating evidence suggests that suppression of glycogen accumulation represents a potential therapeutic approach for treating these GSDs. Using a fluorescence polarization assay designed to screen for inhibitors of the key glycogen synthetic enzyme, glycogen synthase (GS), we identified a substituted imidazole, (rac)-2-methoxy-4-(1-(2-(1-methylpyrrolidin-2-yl)ethyl)-4-phenyl-1H-imidazol-5-yl)phenol (H23), as a first-in-class inhibitor for yeast GS 2 (yGsy2p). Data from X-ray crystallography at 2.85 Å, as well as kinetic data, revealed that H23 bound within the uridine diphosphate glucose binding pocket of yGsy2p. The high conservation of residues between human and yeast GS in direct contact with H23 informed the development of around 500 H23 analogs. These analogs produced a structure-activity relationship profile that led to the identification of a substituted pyrazole, 4-(4-(4-hydroxyphenyl)-3-(trifluoromethyl)-1H-pyrazol-5-yl)pyrogallol, with a 300-fold improved potency against human GS. These substituted pyrazoles possess a promising scaffold for drug development efforts targeting GS activity in GSDs associated with excess glycogen accumulation.
Collapse
Affiliation(s)
- Buyun Tang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Mykhaylo S Frasinyuk
- V. P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, NAS of Ukraine, Kyiv 02094, Ukraine.,National University of Food Technologies, Kyiv 01601, Ukraine
| | - Vimbai M Chikwana
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Krishna K Mahalingan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Cynthia A Morgan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Dyann M Segvich
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | | | - Galyna P Mrug
- V. P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, NAS of Ukraine, Kyiv 02094, Ukraine.,National University of Food Technologies, Kyiv 01601, Ukraine
| | - Przemyslaw Wyrebek
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington 40506, Kentucky, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington 40536, Kentucky, United States
| | - David S Watt
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington 40506, Kentucky, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington 40536, Kentucky, United States.,Lucille Parker Markey Cancer Center, University of Kentucky, Lexington 40536, Kentucky, United States
| | - Anna A DePaoli-Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Peter J Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| | - Thomas D Hurley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis 46202, Indiana, United States
| |
Collapse
|
19
|
mTOR-Related Cell-Clearing Systems in Epileptic Seizures, an Update. Int J Mol Sci 2020; 21:ijms21051642. [PMID: 32121250 PMCID: PMC7084443 DOI: 10.3390/ijms21051642] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 02/06/2023] Open
Abstract
Recent evidence suggests that autophagy impairment is implicated in the epileptogenic mechanisms downstream of mTOR hyperactivation. This holds true for a variety of genetic and acquired epileptic syndromes besides malformations of cortical development which are classically known as mTORopathies. Autophagy suppression is sufficient to induce epilepsy in experimental models, while rescuing autophagy prevents epileptogenesis, improves behavioral alterations, and provides neuroprotection in seizure-induced neuronal damage. The implication of autophagy in epileptogenesis and maturation phenomena related to seizure activity is supported by evidence indicating that autophagy is involved in the molecular mechanisms which are implicated in epilepsy. In general, mTOR-dependent autophagy regulates the proliferation and migration of inter-/neuronal cortical progenitors, synapse development, vesicular release, synaptic plasticity, and importantly, synaptic clustering of GABAA receptors and subsequent excitatory/inhibitory balance in the brain. Similar to autophagy, the ubiquitin–proteasome system is regulated downstream of mTOR, and it is implicated in epileptogenesis. Thus, mTOR-dependent cell-clearing systems are now taking center stage in the field of epilepsy. In the present review, we discuss such evidence in a variety of seizure-related disorders and models. This is expected to provide a deeper insight into the molecular mechanisms underlying seizure activity.
Collapse
|
20
|
Adriaens ME, Lodder EM, Moreno‐Moral A, Šilhavý J, Heinig M, Glinge C, Belterman C, Wolswinkel R, Petretto E, Pravenec M, Remme CA, Bezzina CR. Systems Genetics Approaches in Rat Identify Novel Genes and Gene Networks Associated With Cardiac Conduction. J Am Heart Assoc 2019; 7:e009243. [PMID: 30608189 PMCID: PMC6404199 DOI: 10.1161/jaha.118.009243] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Background Electrocardiographic (ECG) parameters are regarded as intermediate phenotypes of cardiac arrhythmias. Insight into the genetic underpinnings of these parameters is expected to contribute to the understanding of cardiac arrhythmia mechanisms. Here we used HXB/BXH recombinant inbred rat strains to uncover genetic loci and candidate genes modulating ECG parameters. Methods and Results RR interval, PR interval, QRS duration, and QTc interval were measured from ECGs obtained in 6 male rats from each of the 29 available HXB/BXH recombinant inbred strains. Genes at loci displaying significant quantitative trait loci (QTL) effects were prioritized by assessing the presence of protein‐altering variants, and by assessment of cis expression QTL (eQTL) effects and correlation of transcript abundance to the respective trait in the heart. Cardiac RNA‐seq data were additionally used to generate gene co‐expression networks. QTL analysis of ECG parameters identified 2 QTL for PR interval, respectively, on chromosomes 10 and 17. At the chromosome 10 QTL, cis‐eQTL effects were identified for Acbd4, Cd300lg, Fam171a2, and Arhgap27; the transcript abundance in the heart of these 4 genes was correlated with PR interval. At the chromosome 17 QTL, a cis‐eQTL was uncovered for Nhlrc1 candidate gene; the transcript abundance of this gene was also correlated with PR interval. Co‐expression analysis furthermore identified 50 gene networks, 6 of which were correlated with PR interval or QRS duration, both parameters of cardiac conduction. Conclusions These newly identified genetic loci and gene networks associated with the ECG parameters of cardiac conduction provide a starting point for future studies with the potential of identifying novel mechanisms underlying cardiac electrical function.
Collapse
Affiliation(s)
- Michiel E. Adriaens
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
- Maastricht Centre for Systems BiologyMaastricht UniversityMaastrichtThe Netherlands
| | - Elisabeth M. Lodder
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| | | | - Jan Šilhavý
- Institute of PhysiologyAcademy of Sciences of the Czech RepublicPragueCzech Republic
| | - Matthias Heinig
- Institute of Computational BiologyHelmholtz Zentrum MünchenMünchenGermany
| | - Charlotte Glinge
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| | - Charly Belterman
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| | - Rianne Wolswinkel
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| | - Enrico Petretto
- The MRC London Institute of Medical SciencesImperial College LondonLondonUnited Kingdom
- Duke‐NUS Medical SchoolSingapore
| | - Michal Pravenec
- Institute of PhysiologyAcademy of Sciences of the Czech RepublicPragueCzech Republic
| | - Carol Ann Remme
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| | - Connie R. Bezzina
- Department of Experimental CardiologyHeart CentreAcademic Medical Center AmsterdamAmsterdamThe Netherlands
| |
Collapse
|
21
|
The best evidence for progressive myoclonic epilepsy: A pathway to precision therapy. Seizure 2019; 71:247-257. [PMID: 31476531 DOI: 10.1016/j.seizure.2019.08.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/21/2019] [Accepted: 08/23/2019] [Indexed: 12/13/2022] Open
Abstract
Progressive Myoclonus Epilepsies (PMEs) are a group of uncommon clinically and genetically heterogeneous disorders characterised by myoclonus, generalized epilepsy, and neurological deterioration, including dementia and ataxia. PMEs may have infancy, childhood, juvenile or adult onset, but usually present in late childhood or adolescence, at variance from epileptic encephalopathies, which start with polymorphic seizures in early infancy. Neurophysiologic recordings are suited to describe faithfully the time course of the shock-like muscle contractions which characterize myoclonus. A combination of positive and negative myoclonus is typical of PMEs. The gene defects for most PMEs (Unverricht-Lundborg disease, Lafora disease, several forms of neuronal ceroid lipofuscinoses, myoclonus epilepsy with ragged-red fibers [MERRF], and type 1 and 2 sialidoses) have been identified. PMEs are uncommon disorders, difficult to diagnose in the absence of extensive experience. Thus, aetiology is undetermined in many patients, despite the advance in molecular medicine. Treatment of PMEs remains essentially symptomaticof seizures and myoclonus, together with palliative, supportive, and rehabilitative measures. The response to therapy may initially be relatively favourable, afterwards however, seizures may become more frequent, and progressive neurologic decline occurs. The prognosis of a PME depends on the specific disease. The history of PMEs revealed that the international collaboration and sharing experience is the right way to proceed. This emerging picture and biological insights will allow us to find ways to provide the patients with meaningful treatment.
Collapse
|
22
|
Muñoz-Ballester C, Santana N, Perez-Jimenez E, Viana R, Artigas F, Sanz P. In vivo glutamate clearance defects in a mouse model of Lafora disease. Exp Neurol 2019; 320:112959. [PMID: 31108086 DOI: 10.1016/j.expneurol.2019.112959] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/13/2019] [Accepted: 05/16/2019] [Indexed: 12/29/2022]
Abstract
Lafora disease (LD) is a fatal rare neurodegenerative disorder characterized by epilepsy, neurodegeneration and insoluble polyglucosan accumulation in brain and other peripheral tissues. Although in the last two decades we have increased our knowledge on the molecular basis underlying the pathophysiology of LD, only a small part of the research in LD has paid attention to the mechanisms triggering one of the most lethal features of the disease: epilepsy. Recent studies in our laboratory suggested that a dysfunction in the activity of the mouse astrocytic glutamate transporter 1 (GLT-1) could contribute to epilepsy in LD. In this work, we present new in vivo evidence of a GLT-1 dysfunction, contributing to increased levels of extracellular glutamate in the hippocampus of a mouse model of Lafora disease (Epm2b-/-, lacking the E3-ubiquitin ligase malin). According to our results, Epm2b-/- mice showed an increased neuronal activity, as assessed by c-fos expression, in the hippocampus, an area directly correlated to epileptogenesis. This brain area presented lesser ability to remove synaptic glutamate after local GLT-1 blockade with dihydrokainate (DHK), in comparison to Epm2b+/+ animals, suggesting that these animals have a compromised glutamate clearance when a challenging condition was presented. These results correlate with a hippocampal upregulation of the minor isoform of the Glt-1 gene, named Glt-1b, which has been associated with compensatory mechanisms activated in response to neuronal stress. In conclusion, the hippocampus of Epm2b-/- mice presents an in vivo impairment in glutamate uptake which could contribute to epileptogenesis.
Collapse
Affiliation(s)
- C Muñoz-Ballester
- IBV-CSIC. Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - N Santana
- Department of Neurochemistry and Neuropharmacology, Institut d'Investigacions Biomédiques de Barcelona, CSIC, Barcelona, Spain
| | - E Perez-Jimenez
- IBV-CSIC. Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - R Viana
- IBV-CSIC. Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - F Artigas
- Department of Neurochemistry and Neuropharmacology, Institut d'Investigacions Biomédiques de Barcelona, CSIC, Barcelona, Spain; Instituto de Investigaciones Biomédicas August Pi i Sunyer (IDIBAPS), Barcelona, Spain; CIBERSAM, Centro Investigación Biomédica en Red de Salud Mental, Barcelona, Spain
| | - P Sanz
- IBV-CSIC. Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain; CIBERER. Centro de Investigación Biomédica en Red de Enfermedades Raras, group U742, Valencia, Spain.
| |
Collapse
|
23
|
Desdentado L, Espert R, Sanz P, Tirapu-Ustarroz J. [Lafora disease: a review of the literature]. Rev Neurol 2019; 68:66-74. [PMID: 30638256 PMCID: PMC6531605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
INTRODUCTION Lafora disease is autosomal recessive progressive myoclonus epilepsy with late childhood-to teenage-onset caused by loss-of-function mutations in either EPM2A or EPM2B genes encoding laforin or malin, respectively. DEVELOPMENT The main symptoms of Lafora disease, which worsen progressively, are: myoclonus, occipital seizures, generalized tonic-clonic seizures, cognitive decline, neuropsychiatric syptoms and ataxia with a fatal outcome. Pathologically, Lafora disease is characterized by the presence of polyglucosans deposits (named Lafora bodies), in the brain, liver, muscle and sweat glands. Diagnosis of Lafora disease is made through clinical, electrophysiological, histological and genetic findings. Currently, there is no treatment to cure or prevent the development of the disease. Traditionally, antiepileptic drugs are used for the management of myoclonus and seizures. However, patients become drug-resistant after the initial stage. CONCLUSIONS Lafora disease is a rare pathology that has serious consequences for patients and their caregivers despite its low prevalence. Therefore, continuing research in order to clarify the underlying mechanisms and hopefully developing new palliative and curative treatments for the disease is necessary.
Collapse
Affiliation(s)
- L Desdentado
- Hospital Clinico Universitario de Valencia, 46010 Valencia, Espana
| | - R Espert
- Hospital Clinico Universitario de Valencia, 46010 Valencia, Espana
- Universidad de Valencia, 46071 Valencia, Espana
| | - P Sanz
- Instituto de Biomedicina de Valencia, 46010 Valencia, Venezuela
| | | |
Collapse
|
24
|
Abstract
Lafora's disease is a neurodegenerative disorder caused by recessive loss-of-function mutations in the EPM2A (laforin glycogen phosphatase) or EPM2B (malin E3 ubiquitin ligase) genes. Neuropathology is characterized by malformed precipitated glycogen aggregates termed Lafora bodies. Asymptomatic until adolescence, patients undergo first insidious then rapid progressive myoclonus epilepsy toward a vegetative state and death within a decade. Laforin and malin interact to regulate glycogen phosphorylation and chain length pattern, the latter critical to glycogen's solubility. Significant gaps remain in precise mechanistic understanding. However, demonstration that partial reduction in brain glycogen synthesis near-completely prevents the disease in its genetic animal models opens a direct present path to therapy.
Collapse
Affiliation(s)
- Brandy Verhalen
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Susan Arnold
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Berge A. Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| |
Collapse
|
25
|
Kim JH, Kim HJ, Yu DH, Kweon HS, Huh YH, Kim HR. Changes in numbers and size of synaptic vesicles of cortical neurons induced by exposure to 835 MHz radiofrequency-electromagnetic field. PLoS One 2017; 12:e0186416. [PMID: 29045446 PMCID: PMC5646811 DOI: 10.1371/journal.pone.0186416] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 09/29/2017] [Indexed: 12/17/2022] Open
Abstract
We studied the effects of radiofrequency electromagnetic fields (RF-EMFs) exposure on neuronal functions of mice. Particularly, we focused on RF-EMF effects on synaptic vesicles (SVs), which store neurotransmitters at axon terminals or synaptic boutons. C57 BL/6 mice were exposed to 835 MHz RF-EMF (4.0 W/kg SAR, for 5 h daily) and alterations in SVs at presynaptic terminals in the cerebral cortex were determined. Ultrastructure of randomly selected cortical neurons was observed using typical electron microscopy and bio-high voltage electron microscopy (Bio-HVEM) methods, which enable the estimation of the numbers and size of SVs. The density of the SVs (number /10 μm2 or 40 μm3) was significantly decreased in the presynaptic boutons of cortical neurons after RF-EMF exposure. Furthermore, qPCR and immunoblotting analyses revealed that the expression of synapsins I/II (Syns I/II) genes and proteins were significantly decreased in the cortical neurons of RF-EMF exposed mice. The present study suggested that alteration of SVs and Syn levels may result in alterations of neurotransmitters in the cerebral cortex following RF-EMF exposure.
Collapse
Affiliation(s)
- Ju Hwan Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan, Chungnam, South Korea
| | - Hyo-Jeong Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan, Chungnam, South Korea
- Center for Electron Microscopy Research, Korea Basic Science Institute, Ochang, Chungbuk, South Korea
| | - Da-Hyeon Yu
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan, Chungnam, South Korea
| | - Hee-Seok Kweon
- Center for Electron Microscopy Research, Korea Basic Science Institute, Ochang, Chungbuk, South Korea
| | - Yang Hoon Huh
- Center for Electron Microscopy Research, Korea Basic Science Institute, Ochang, Chungbuk, South Korea
- * E-mail: (HRK); (YHH)
| | - Hak Rim Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan, Chungnam, South Korea
- * E-mail: (HRK); (YHH)
| |
Collapse
|
26
|
Kim JH, Yu DH, Kim HR. Activation of autophagy at cerebral cortex and apoptosis at brainstem are differential responses to 835 MHz RF-EMF exposure. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2017; 21:179-188. [PMID: 28280411 PMCID: PMC5343051 DOI: 10.4196/kjpp.2017.21.2.179] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 12/09/2016] [Accepted: 12/18/2016] [Indexed: 12/19/2022]
Abstract
With the explosive increase in exposure to radiofrequency electromagnetic fields (RF-EMF) emitted by mobile phones, public concerns have grown over the last few decades with regard to the potential effects of EMF exposure on the nervous system in the brain. Many researchers have suggested that RF-EMFs can effect diverse neuronal alterations in the brain, thereby affecting neuronal functions as well as behavior. Previously, we showed that long-term exposure to 835 MHz RF-EMF induces autophagy in the mice brain. In this study, we explore whether short-term exposure to RF-EMF leads to the autophagy pathway in the cerebral cortex and brainstem at 835 MHz with a specific absorption rate (SAR) of 4.0 W/kg for 4 weeks. Increased levels of autophagy genes and proteins such as LC3B-II and Beclin1 were demonstrated and the accumulation of autophagosomes and autolysosomes was observed in cortical neurons whereas apoptosis pathways were up-regulated in the brainstem but not in the cortex following 4 weeks of RF exposure. Taken together, the present study indicates that monthly exposure to RF-EMF induces autophagy in the cerebral cortex and suggests that autophagic degradation in cortical neurons against a stress of 835 MHz RF during 4 weeks could correspond to adaptation to the RF stress environment. However, activation of apoptosis rather than autophagy in the brainstem is suggesting the differential responses to the RF-EMF stresses in the brain system.
Collapse
Affiliation(s)
- Ju Hwan Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 31116, Korea
| | - Da-Hyeon Yu
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 31116, Korea
| | - Hak Rim Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan 31116, Korea
| |
Collapse
|
27
|
Nasri A, Mansour M, Kacem A, Derbali H, Yahya M, Riahi A, Bedoui I, Messelmani M, Zaouali J, Fekih-Mrissa N, Bouzayène A, Mrissa R. Trouble obsessionnel compulsif pédiatrique : forme inaugurale inhabituelle de la maladie de Lafora. Encephale 2017; 43:90-94. [DOI: 10.1016/j.encep.2016.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 08/31/2015] [Indexed: 11/17/2022]
|
28
|
Kim JH, Yu DH, Huh YH, Lee EH, Kim HG, Kim HR. Long-term exposure to 835 MHz RF-EMF induces hyperactivity, autophagy and demyelination in the cortical neurons of mice. Sci Rep 2017; 7:41129. [PMID: 28106136 PMCID: PMC5247706 DOI: 10.1038/srep41129] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 12/15/2016] [Indexed: 12/19/2022] Open
Abstract
Radiofrequency electromagnetic field (RF-EMF) is used globally in conjunction with mobile communications. There are public concerns of the perceived deleterious biological consequences of RF-EMF exposure. This study assessed neuronal effects of RF-EMF on the cerebral cortex of the mouse brain as a proxy for cranial exposure during mobile phone use. C57BL/6 mice were exposed to 835 MHz RF-EMF at a specific absorption rate (SAR) of 4.0 W/kg for 5 hours/day during 12 weeks. The aim was to examine activation of autophagy pathway in the cerebral cortex, a brain region that is located relatively externally. Induction of autophagy genes and production of proteins including LC3B-II and Beclin1 were increased and accumulation of autolysosome was observed in neuronal cell bodies. However, proapoptotic factor Bax was down-regulted in the cerebral cortex. Importantly, we found that RF-EMF exposure led to myelin sheath damage and mice displayed hyperactivity-like behaviour. The data suggest that autophagy may act as a protective pathway for the neuronal cell bodies in the cerebral cortex during radiofrequency exposure. The observations that neuronal cell bodies remained structurally stable but demyelination was induced in cortical neurons following prolonged RF-EMF suggests a potential cause of neurological or neurobehavioural disorders.
Collapse
Affiliation(s)
- Ju Hwan Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| | - Da-Hyeon Yu
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| | - Yang Hoon Huh
- Center for Electron Microscopy Research, Korea Basic Science Institute, Ochang, Chung-Buk, Republic of Korea
| | - Eun Ho Lee
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| | - Hyung-Gun Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| | - Hak Rim Kim
- Department of Pharmacology, College of Medicine, Dankook University, Cheonan-si, Chungnam, Republic of Korea
| |
Collapse
|
29
|
Goldsmith D, Minassian BA. Efficacy and tolerability of perampanel in ten patients with Lafora disease. Epilepsy Behav 2016; 62:132-5. [PMID: 27459034 PMCID: PMC5691360 DOI: 10.1016/j.yebeh.2016.06.041] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/28/2016] [Accepted: 06/29/2016] [Indexed: 01/12/2023]
Abstract
Lafora disease (LD) is a fatal intractable adolescence-onset progressive myoclonus epilepsy. Recently, two single-case studies reported drastic reductions in seizures and myoclonus with the AMPA antagonist perampanel and improved activities of daily living. We proceeded to study the effect of perampanel on 10 patients with genetically confirmed LD with disease duration ranging from 2 to 27years. Open-label perampanel was added to ongoing medications to a mean dose of 6.7mg/day. Seizures, myoclonus, functional disability, and cognition scores were measured for the third and ninth months following initiation and compared with those of the month prior to the start of therapy. Three patients withdrew because of inefficacy or side effects. Four had significant reduction in seizures of greater than 74% from baseline. Seven had major improvement in myoclonus with group-adjusted sum score of myoclonus intensity reduced from 7.01 at baseline to 5.67 and 5.18 at 3 and 9months, respectively. There was no significant improvement in disability and cognition. While not universal, perampanel adjunctive therapy appears to confer particular benefit not commonly seen with other antiepileptic drugs on seizures and myoclonus in LD. Improvement in the extremely disabling myoclonus of LD is a major benefit in this devastating disease.
Collapse
Affiliation(s)
- Danielle Goldsmith
- Chelsea's Hope: Lafora Children Research Fund, Danville, CA, USA; Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Berge A Minassian
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; The Institute of Medical Science and The Department of Paediatrics (Neurology), University of Toronto, ON, Canada.
| |
Collapse
|
30
|
Marcián V, Filip P, Bareš M, Brázdil M. Cerebellar Dysfunction and Ataxia in Patients with Epilepsy: Coincidence, Consequence, or Cause? TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2016; 6:376. [PMID: 27375960 PMCID: PMC4925921 DOI: 10.7916/d8kh0nbt] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Accepted: 05/05/2016] [Indexed: 12/15/2022]
Abstract
Basic epilepsy teachings assert that seizures arise from the cerebral cortex, glossing over infratentorial structures such as the cerebellum that are believed to modulate rather than generate seizures. Nonetheless, ataxia and other clinical findings in epileptic patients are slowly but inevitably drawing attention to this neural node. Tracing the evolution of this line of inquiry from the observed coincidence of cerebellar atrophy and cerebellar dysfunction (most apparently manifested as ataxia) in epilepsy to their close association, this review considers converging clinical, physiological, histological, and neuroimaging evidence that support incorporating the cerebellum into epilepsy pathology. We examine reports of still controversial cerebellar epilepsy, studies of cerebellar stimulation alleviating paroxysmal epileptic activity, studies and case reports of cerebellar lesions directly associated with seizures, and conditions in which ataxia is accompanied by epileptic seizures. Finally, the review substantiates the role of this complex brain structure in epilepsy whether by coincidence, as a consequence of deleterious cortical epileptic activity or antiepileptic drugs, or the very cause of the disease.
Collapse
Affiliation(s)
- Václav Marcián
- First Department of Neurology, St. Anne's University Hospital, Brno, Czech Republic; Medical Faculty of Masaryk University, Brno, Czech Republic.,First Department of Neurology, St. Anne's University Hospital, Brno, Czech Republic; Medical Faculty of Masaryk University, Brno, Czech Republic; Behavioral and Social Neuroscience Research Group, CEITEC (Central European Institute of Technology), Masaryk University, Brno, Czech Republic; Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Pavel Filip
- First Department of Neurology, St. Anne's University Hospital, Brno, Czech Republic; Medical Faculty of Masaryk University, Brno, Czech Republic
| | - Martin Bareš
- First Department of Neurology, St. Anne's University Hospital, Brno, Czech Republic; Medical Faculty of Masaryk University, Brno, Czech Republic; Behavioral and Social Neuroscience Research Group, CEITEC (Central European Institute of Technology), Masaryk University, Brno, Czech Republic; Department of Neurology, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Milan Brázdil
- First Department of Neurology, St. Anne's University Hospital, Brno, Czech Republic; Medical Faculty of Masaryk University, Brno, Czech Republic; Behavioral and Social Neuroscience Research Group, CEITEC (Central European Institute of Technology), Masaryk University, Brno, Czech Republic
| |
Collapse
|
31
|
Homeostasis of the astrocytic glutamate transporter GLT-1 is altered in mouse models of Lafora disease. Biochim Biophys Acta Mol Basis Dis 2016; 1862:1074-83. [PMID: 26976331 DOI: 10.1016/j.bbadis.2016.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 02/04/2016] [Accepted: 03/10/2016] [Indexed: 11/20/2022]
Abstract
Lafora disease (LD, OMIM 254780) is a fatal rare disorder characterized by epilepsy and neurodegeneration. Although in recent years a lot of information has been gained on the molecular basis of the neurodegeneration that accompanies LD, the molecular basis of epilepsy is poorly understood. Here, we present evidence indicating that the homeostasis of glutamate transporter GLT-1 (EAAT2) is compromised in mouse models of LD. Our results indicate that primary astrocytes from LD mice have reduced capacity of glutamate transport, probably because they present a reduction in the levels of the glutamate transporter at the plasma membrane. On the other hand, the overexpression in cellular models of laforin and malin, the two proteins related to LD, results in an accumulation of GLT-1 (EAAT2) at the plasma membrane and in a severe reduction of the ubiquitination of the transporter. All these results suggest that the laforin/malin complex slows down the endocytic recycling of the GLT-1 (EAAT2) transporter. Since, defects in the function of this transporter lead to excitotoxicity and epilepsy, we suggest that the epilepsy that accompanies LD could be due, at least in part, to deficiencies in the function of the GLT-1 (EAAT2) transporter.
Collapse
|
32
|
Abstract
Common somatic conditions are bound to occur by chance in individuals with neurological disorders as prevalent as epilepsy, but when biological links underlying the comorbidity can be uncovered, the relationship may provide clues into the origin and mechanisms of both. The expanding list of monogenic epilepsies and their associated clinical features offer a remarkable opportunity to mine the epilepsy genome for coordinate neurodevelopmental phenotypes and examine their pathogenic mechanisms. Defined single-gene-linked epilepsy syndromes identified to date include all of the most frequently cited comorbidities, such as cognitive disorders, autism, migraine, mood disorders, late-onset dementia, and even premature lethality. Gene-linked comorbidities may be aggravated by, or independent of, seizure history. Mutations in these genes establish clear biological links between abnormal neuronal synchronization and a variety of neurobehavioral disorders, and critically substantiate the definition of epilepsy as a complex spectrum disorder. Mapping the neural circuitry of epilepsy comorbidities and understanding their single-gene risk should substantially clarify this challenging aspect of clinical epilepsy management.
Collapse
Affiliation(s)
- Jeffrey L Noebels
- Developmental Neurogenetics Laboratory, Departments of Neurology, Neuroscience, and Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| |
Collapse
|
33
|
Zinzow-Kramer WM, Horton BM, McKee CD, Michaud JM, Tharp GK, Thomas JW, Tuttle EM, Yi S, Maney DL. Genes located in a chromosomal inversion are correlated with territorial song in white-throated sparrows. GENES BRAIN AND BEHAVIOR 2015; 14:641-54. [PMID: 26463687 DOI: 10.1111/gbb.12252] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/28/2015] [Accepted: 09/09/2015] [Indexed: 01/10/2023]
Abstract
The genome of the white-throated sparrow (Zonotrichia albicollis) contains an inversion polymorphism on chromosome 2 that is linked to predictable variation in a suite of phenotypic traits including plumage color, aggression and parental behavior. Differences in gene expression between the two color morphs, which represent the two common inversion genotypes (ZAL2/ZAL2 and ZAL2/ZAL2(m) ), may therefore advance our understanding of the molecular underpinnings of these phenotypes. To identify genes that are differentially expressed between the two morphs and correlated with behavior, we quantified gene expression and terrirorial aggression, including song, in a population of free-living white-throated sparrows. We analyzed gene expression in two brain regions, the medial amygdala (MeA) and hypothalamus. Both regions are part of a 'social behavior network', which is rich in steroid hormone receptors and previously linked with territorial behavior. Using weighted gene co-expression network analyses, we identified modules of genes that were correlated with both morph and singing behavior. The majority of these genes were located within the inversion, showing the profound effect of the inversion on the expression of genes captured by the rearrangement. These modules were enriched with genes related to retinoic acid signaling and basic cellular functioning. In the MeA, the most prominent pathways were those related to steroid hormone receptor activity. Within these pathways, the only gene encoding such a receptor was ESR1 (estrogen receptor 1), a gene previously shown to predict song rate in this species. The set of candidate genes we identified may mediate the effects of a chromosomal inversion on territorial behavior.
Collapse
Affiliation(s)
| | - B M Horton
- Department of Psychology, Emory University, Atlanta, GA
| | - C D McKee
- Department of Psychology, Emory University, Atlanta, GA
| | - J M Michaud
- Department of Psychology, Emory University, Atlanta, GA
| | - G K Tharp
- Yerkes Nonhuman Primate Genomics Core, Emory University, Atlanta, GA
| | - J W Thomas
- NIH Intramural Sequencing Center, National Human Genome Research Institute, NIH, Rockville, MD
| | - E M Tuttle
- Department of Biology, Indiana State University, Terre Haute, IN.,The Center for Genomic Advocacy, Indiana State University, Terre Haute, IN
| | - S Yi
- School of Biology, Georgia Institute of Technology, Atlanta, GA, USA
| | - D L Maney
- Department of Psychology, Emory University, Atlanta, GA
| |
Collapse
|
34
|
Noebels J. Pathway-driven discovery of epilepsy genes. Nat Neurosci 2015; 18:344-50. [PMID: 25710836 DOI: 10.1038/nn.3933] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/22/2014] [Indexed: 12/12/2022]
Abstract
Epilepsy genes deliver critical insights into the molecular control of brain synchronization and are revolutionizing our understanding and treatment of the disease. The epilepsy-associated genome is rapidly expanding, and two powerful complementary approaches, isolation of de novo exome variants in patients and targeted mutagenesis in model systems, account for the steep increase. In sheer number, the tally of genes linked to seizures will likely match that of cancer and exceed it in biological diversity. The proteins act within most intracellular compartments and span the molecular determinants of firing and wiring in the developing brain. Every facet of neurotransmission, from dendritic spine to exocytotic machinery, is in play, and defects of synaptic inhibition are over-represented. The contributions of somatic mutations and noncoding microRNAs are also being explored. The functional spectrum of established epilepsy genes and the arrival of rapid, precise technologies for genome editing now provide a robust scaffold to prioritize hypothesis-driven discovery and further populate this genetic proto-map. Although each gene identified offers translational potential to stratify patient care, the complexity of individual variation and covert actions of genetic modifiers may confound single-gene solutions for the clinical disorder. In vivo genetic deconstruction of epileptic networks, ex vivo validation of variant profiles in patient-derived induced pluripotent stem cells, in silico variant modeling and modifier gene discovery, now in their earliest stages, will help clarify individual patterns. Because seizures stand at the crossroads of all neuronal synchronization disorders in the developing and aging brain, the neurobiological analysis of epilepsy-associated genes provides an extraordinary gateway to new insights into higher cortical function.
Collapse
Affiliation(s)
- Jeffrey Noebels
- Developmental Neurogenetics Laboratory, Departments of Neurology, Neuroscience, and Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| |
Collapse
|
35
|
Berthier A, Payá M, García-Cabrero AM, Ballester MI, Heredia M, Serratosa JM, Sánchez MP, Sanz P. Pharmacological Interventions to Ameliorate Neuropathological Symptoms in a Mouse Model of Lafora Disease. Mol Neurobiol 2015; 53:1296-1309. [PMID: 25627694 DOI: 10.1007/s12035-015-9091-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/12/2015] [Indexed: 10/24/2022]
Abstract
Lafora disease (LD, OMIM 254780) is a rare fatal neurodegenerative disorder that usually occurs during childhood with generalized tonic-clonic seizures, myoclonus, absences, drop attacks, or visual seizures. Unfortunately, at present, available treatments are only palliatives and no curative drugs are available yet. The hallmark of the disease is the accumulation of insoluble polyglucosan inclusions, called Lafora bodies (LBs), within the neurons but also in heart, muscle, and liver cells. Mouse models lacking functional EPM2A or EPM2B genes (the two major loci related to the disease) recapitulate the Lafora disease phenotype: they accumulate polyglucosan inclusions, show signs of neurodegeneration, and have a dysregulation of protein clearance and endoplasmic reticulum stress response. In this study, we have subjected a mouse model of LD (Epm2b-/-) to different pharmacological interventions aimed to alleviate protein clearance and endoplasmic reticulum stress. We have used two chemical chaperones, trehalose and 4-phenylbutyric acid. In addition, we have used metformin, an activator of AMP-activated protein kinase (AMPK), as it has a recognized neuroprotective role in other neurodegenerative diseases. Here, we show that treatment with 4-phenylbutyric acid or metformin decreases the accumulation of Lafora bodies and polyubiquitin protein aggregates in the brain of treated animals. 4-Phenylbutyric acid and metformin also diminish neurodegeneration (measured in terms of neuronal loss and reactive gliosis) and ameliorate neuropsychological tests of Epm2b-/- mice. As these compounds have good safety records and are already approved for clinical uses on different neurological pathologies, we think that the translation of our results to the clinical practice could be straightforward.
Collapse
Affiliation(s)
- Arnaud Berthier
- Instituto de Biomedicina de Valencia (CSIC), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010, Valencia, Spain
| | - Miguel Payá
- Departamento de Farmacología, Facultad de Farmacia, Universidad de Valencia and Centro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), 46100, Valencia, Spain
| | - Ana M García-Cabrero
- Fundación Jimenez Diaz and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28040, Madrid, Spain
| | - Maria Inmaculada Ballester
- Instituto de Biomedicina de Valencia (CSIC), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010, Valencia, Spain
| | - Miguel Heredia
- Instituto de Biomedicina de Valencia (CSIC), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010, Valencia, Spain
| | - José M Serratosa
- Fundación Jimenez Diaz and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28040, Madrid, Spain
| | - Marina P Sánchez
- Fundación Jimenez Diaz and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28040, Madrid, Spain
| | - Pascual Sanz
- Instituto de Biomedicina de Valencia (CSIC), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010, Valencia, Spain.
| |
Collapse
|
36
|
Dirani M, Nasreddine W, Abdulla F, Beydoun A. Seizure control and improvement of neurological dysfunction in Lafora disease with perampanel. EPILEPSY & BEHAVIOR CASE REPORTS 2014; 2:164-6. [PMID: 25667898 PMCID: PMC4307869 DOI: 10.1016/j.ebcr.2014.09.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 09/04/2014] [Indexed: 12/31/2022]
Abstract
Lafora disease is a rare and fatal disease characterized by seizures, progressive cognitive and behavioral deterioration, as well as cerebellar dysfunction. Currently, there is no efficacious treatment that will control the seizures and improve the cognitive decline in this disease. We report a patient with Lafora disease who experienced a dramatic amelioration in her seizure frequency as well as the associated neurological and cognitive dysfunction following initiation of treatment with perampanel administered as monotherapy. Perampanel is the first potentially efficacious treatment for Lafora disease. We discuss a potential mechanism for the efficacy of perampanel in this disease.
Collapse
Affiliation(s)
- Maya Dirani
- Division of Pediatric Neurology, American University of Beirut Medical Center, Lebanon
| | - Wassim Nasreddine
- Department of Neurology, American University of Beirut Medical Center, Lebanon
| | - Fatima Abdulla
- Department of Clinical Neurosciences, Salmaniya Medical Complex, Bahrain
| | - Ahmad Beydoun
- Department of Neurology, American University of Beirut Medical Center, Lebanon
- Corresponding author at: American University of Beirut Medical Center, PO Box 11-0236, Riad El-Solh, 1107 2020 Beirut, Lebanon. Tel.: + 961 3322904; fax: + 961 1370814.
| |
Collapse
|
37
|
Giorgi FS, Biagioni F, Lenzi P, Frati A, Fornai F. The role of autophagy in epileptogenesis and in epilepsy-induced neuronal alterations. J Neural Transm (Vienna) 2014; 122:849-62. [DOI: 10.1007/s00702-014-1312-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 09/09/2014] [Indexed: 12/12/2022]
|